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HFES Tables of Contents: 000102030405060708091011121314

Proceedings of the Human Factors and Ergonomics Society 50th Annual Meeting 2006-10-16

Fullname:Proceedings of the Human Factors and Ergonomics Society 50th Annual Meeting
Location:San Francisco, California
Dates:2006-Oct-16 to 2006-Oct-20
Publisher:HFES
Standard No:ISBN: 0-945289-32-4, 978-0-945289-32-6; hcibib: HFES06
Papers:575
Pages:2716
Links:Online Proceedings | Conference Home Page | Online Order Form
  1. HFES 2006-10-16 Volume 50
    1. AEROSPACE SYSTEMS: Air Traffic Control
    2. AEROSPACE SYSTEMS: Business Case for Civil Aviation Human Factors
    3. AEROSPACE SYSTEMS: Cognitive Factors in Aviation
    4. AEROSPACE SYSTEMS: Workload & Training
    5. AEROSPACE SYSTEMS: WorkLoad & Training
    6. AEROSPACE SYSTEMS: Workload & Training
    7. AEROSPACE SYSTEMS: Perceptual Factors in Aviation
    8. AEROSPACE SYSTEMS: Human-Systems Integration Challenges for Constellation
    9. AEROSPACE SYSTEMS: Have a Safe Flight: A Practice-Oriented Session
    10. AEROSPACE SYSTEMS: Aviation at a Distance
    11. AEROSPACE SYSTEMS: Distributed Simulation of ROVs Flying in Terminal Airspace
    12. AEROSPACE SYSTEMS: Human Factors of Remotely Operated Vehicles
    13. AGING: A1 - Aging in the Real World: Practical Research Applications
    14. AGING: A2 - Aging, Cognition, and Abilities
    15. COGNITIVE ENGINEERING AND DECISION MAKING: Automation Reliability and Trust
    16. COGNITIVE ENGINEERING AND DECISION MAKING: Bridging the Gap from Analysis to Design
    17. COGNITIVE ENGINEERING AND DECISION MAKING: Situation Awareness in Complex Domains
    18. COGNITIVE ENGINEERING AND DECISION MAKING: Collaborative Decision Making in Network-Centric Military Operations
    19. COGNITIVE ENGINEERING AND DECISION MAKING: Cognition and Perception in Displays
    20. COGNITIVE ENGINEERING AND DECISION MAKING: Evaluating the Effectiveness of a Joint Cognitive System: Metrics, Techniques, and Frameworks
    21. COGNITIVE ENGINEERING AND DECISION MAKING: Detecting Signals, Events, and Abnormal Situations
    22. COGNITIVE ENGINEERING AND DECISION MAKING: Mediating Factors that Influence Cognition
    23. COGNITIVE ENGINEERING AND DECISION MAKING: Interruptions and Task Resumption
    24. COGNITIVE ENGINEERING AND DECISION MAKING: Models of Complex Domains
    25. COGNITIVE ENGINEERING AND DECISION MAKING: New Directions in the Control of Attention
    26. COGNITIVE ENGINEERING AND DECISION MAKING: Cross-Cultural Interactions: Methods and Motivations for Study
    27. COGNITIVE ENGINEERING AND DECISION MAKING: Taking Cognitive Work Analysis One Step Further
    28. COGNITIVE ENGINEERING AND DECISION MAKING: Cognition in Complex Domains
    29. COGNITIVE ENGINEERING AND DECISION MAKING: Teamwork
    30. COGNITIVE ENGINEERING AND DECISION MAKING: Functional Models of Work Domains
    31. COGNITIVE ENGINEERING AND DECISION MAKING: Choosing Levels of Automation for Better UAV Control
    32. COMMUNICATIONS: Collaboration and Technology-Mediated Communication
    33. COMMUNICATIONS: Communications Student Session
    34. COMMUNICATIONS: Communications Potpourri
    35. COMPUTER SYSTEMS: Novel Usability Methods in Theory and Practice
    36. COMPUTER SYSTEMS: Visualization and Representation on Displays
    37. COMPUTER SYSTEMS: Tactile and Haptic Interfaces
    38. COMPUTER SYSTEMS: Usability Evaluations in Military Systems
    39. COMPUTER SYSTEMS: Voice and Speech Systems: Usability and Performance
    40. COMPUTER SYSTEMS: Input Methods and Interfaces
    41. EDUCATION: Human Systems Integration (HSI) Education and Training
    42. EDUCATION: Teaching HF/E Issues to Varying Audiences
    43. EDUCATION: Accreditation/Recognition of Undergraduate HF/E Programs
    44. ENVIRONMENTAL DESIGN: Office Ergonomic Intervention Panel & 3D Body Scan Method, Measure of Exterior View Lectures
    45. ENVIRONMENTAL DESIGN: Revisiting Sitting Cross-Cultural Aspects of Seating
    46. ENVIRONMENTAL DESIGN: Diagnosing Environments: Environmental and Medical Human Factors
    47. FORENSICS PROFESSIONAL: Issues In Forensic Human Factors
    48. GENERAL SESSION: President's Forum
    49. GENERAL SESSION: Human-Robot Factors: Robots in the Workplace
    50. GENERAL SESSION: Human Factors Applications in Complex Domains
    51. GENERAL SESSION: Integrative Approaches to Understanding Complex Aspects of Human Performance
    52. GENERAL SESSION: Learning from Investigation: Reviewing the First Year of MEDCAS
    53. HEALTH CARE: Understanding and Facilitating Collaboration in Health Care
    54. HEALTH CARE: Teams, Communication, and Culture in Medical Care
    55. HEALTH CARE: Modeling and Decision Making in Health Care
    56. HEALTH CARE: Adverse Events and Reporting Systems in Health Care
    57. HEALTH CARE: Modes of Perception in Medical Tasks
    58. HEALTH CARE: Workflow, Interruptions, and Information Exchange in Health Care
    59. HEALTH CARE: Patients as Partners in Treatment
    60. HEALTH CARE: Reports from the Field: Evaluation of Medical Equipment, Materials and Methods
    61. HUMAN PERFORMANCE: Approaches in Human Performance Modeling
    62. HUMAN PERFORMANCE: Approaches in Human performance modeling
    63. HUMAN PERFORMANCE: Approaches in Human Performance Modeling
    64. HUMAN PERFORMANCE: Exploring Behavior with Human Performance Models
    65. HUMAN PERFORMANCE: Tools for the Human Performance Modeler's Toolkit
    66. HUMAN PERFORMANCE: Tool for the Human Performance Modeler' Toolkit
    67. HUMAN PERFORMANCE: Putting Human Performance Modeling to the Task
    68. INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences in Cognitive Performance
    69. INDIVIDUAL DIFFERENCES IN PERFORMANCE: Diversity of Individual Differences Factors Predicting Performance
    70. INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences Potpourri
    71. INDUSTRIAL ERGONOMICS: The Promise and Limitations of Ergonomics
    72. INDUSTRIAL ERGONOMICS: Postural Influences on Low Back Biomechanics
    73. INDUSTRIAL ERGONOMICS: Prevention of Work-Related Musculoskeletal Injuries
    74. INDUSTRIAL ERGONOMICS: The Neck and Upper Extremity
    75. INDUSTRIAL ERGONOMICS: Slips, Trips, and Falls
    76. INDUSTRIAL ERGONOMICS: Ergonomics of Computer Use
    77. INDUSTRIAL ERGONOMICS: Workplace Design Issues
    78. INDUSTRIAL ERGONOMICS: Evaluation of Industrial Tasks
    79. INDUSTRIAL ERGONOMICS: Quality and Ergonomics
    80. INDUSTRIAL ERGONOMICS: Analysis of Job Risks
    81. INTERNET: Human Factors on the Web: Past, Present, and Visions of the Future
    82. INTERNET: Human Factors on the Internet
    83. MACROERGONOMICS: Macroergonomics and Patient Safety
    84. MACROERGONOMICS: Using Technology to Enhance the Organization
    85. MACROERGONOMICS: Macroergonomics in Decision Making, Teams, and Health Care
    86. PERCEPTION AND PERFORMANCE: Spatial Displays and Spatial Cognition
    87. PERCEPTION AND PERFORMANCE: Tactile Perception and Multimodal Displays
    88. PERCEPTION AND PERFORMANCE: Auditory Perception and Displays
    89. PERCEPTION AND PERFORMANCE: Motion Processing
    90. PERCEPTION AND PERFORMANCE: Vigilance and Brain States
    91. PERCEPTION AND PERFORMANCE: Attention
    92. PERCEPTION AND PERFORMANCE: Perception and Control Tasks
    93. PERCEPTION AND PERFORMANCE: "In Touch" Vibrotactile/Haptic Symposium
    94. PERCEPTION AND PERFORMANCE: Discrimination and Perception
    95. POSTERS: POS1 - Posters
    96. POSTERS: POS2 - Posters
    97. POSTERS: POS3 - Posters
    98. POSTERS: POS4 - Posters
    99. POSTERS: POS5 - Posters
    100. PRODUCT DESIGN: Usability Research and 21st Century Design
    101. PRODUCT DESIGN: Product Potpourri
    102. PRODUCT DESIGN: Tools, Technology, and Aesthetics
    103. PRODUCT DESIGN: Product Design Miscellany
    104. SAFETY: Warnings Plus
    105. SAFETY: Safety Potpourri
    106. SPECIAL SESSION: Demonstrations
    107. SPECIAL SESSION: From Past to Present with the Presidents
    108. SPECIAL SESSION: You Have Five Minutes to Convince Me
    109. SPECIAL SESSION: Symposium on the Littoral Combat Ship
    110. STUDENT FORUM: Career Preparation Panel
    111. STUDENT FORUM: Emerging and Exciting Student Research Part I
    112. STUDENT FORUM: Emerging and Exciting Student Research Part II
    113. SURFACE TRANSPORTATION: Can you hear me now? Distraction, Workload, and Methods
    114. SURFACE TRANSPORTATION: What's Age Got to Do with It? Issues Related to Younger, Experienced, and Older Drivers
    115. SURFACE TRANSPORTATION: The Evolution and Future of the Highway Safety Field Through the Eyes of Multiple Generations of Lauer Awardees
    116. SURFACE TRANSPORTATION: More Than a Feeling: Haptic and Other Warning Systems
    117. SURFACE TRANSPORTATION: Off the Beaten Path: Alternative Topics, Methods, and Techniques
    118. SURFACE TRANSPORTATION: Driver Visual Behavior and Warning Systems
    119. SYSTEM DEVELOPMENT: The Challenge of Integrating Cognitive Requirements into Systems Development: Solutions & Lessons Learned
    120. SYSTEM DEVELOPMENT: Organizational Factors in Design: How to Support Colaborative Relationships and Information Sharing through Network Analysis and Requirements Capture
    121. SYSTEM DEVELOPMENT: Subjective Feedback, Performance Assessments, and Iterative Design-Critical Factors That Drive Design Decisions
    122. TEST AND EVALUATION: Context, Complexity, and Changing Goals: Testing and Evaluation Challenges
    123. TEST AND EVALUATION: Test and Evaluation in the Real World - I
    124. TEST AND EVALUATION: Test and Evaluation Tools and Techniques
    125. TEST AND EVALUATION: Test and Evaluation in the Real World - II
    126. TRAINING: Enhancing Cognitive Processes by Applying Cognitive Theories: Blending Training with Applied Cognitive Psychology
    127. TRAINING: Complex Training for Complex Environments: Expanding Theory to Improve Team Performance
    128. TRAINING: Developing Learner-Centered Simulations to Enhance Learning and Retention
    129. VIRTUAL ENVIRONMENTS: Use of HMDs in Virtual Environments
    130. VIRTUAL ENVIRONMENTS: Performance in Virtual Environments

HFES 2006-10-16 Volume 50

AEROSPACE SYSTEMS: Air Traffic Control

Controller Performance and Attention Allocation in Future Air Traffic Management: Effects of Pilot Intent Information BIBAFull-Text 1-5
  Ericka Rovira; Raja Parasuraman
New Air Traffic Management (ATM) concepts are being considered to cope with increased demands on the airspace. The transition to future ATM will be gradual. Initially, only some aircraft will have the equipment to fully participate in all aspects of the new system, whereas other less well-equipped aircraft will not. The present study investigated how such mixed equipage affects air traffic controller (ATCo) performance and mental workload. Sixteen ATCos performed a simulated ATC task with or without decision support and with varying proportions (low, medium, and high) of traffic mix predictability (i.e. knowledge of aircraft trajectories). Dependent variables included the accuracy and response time in detecting potential conflicts and eye movements. The findings demonstrate that: a) medium traffic mix predictability supports the earlier detection of conflicts; b) automation support improves conflict detection, but c) ATCos make the most eye movements towards unmanaged aircraft.
Using Airport Layout Information to Improve Automatic Speech Recognition for Digitizing Taxi Instructions BIBAFull-Text 6-10
  Fenne Roefs; Erik Theunissen; Richard Jinkins; Brian Moncur
During taxiing, an Electronic Flight Bag (EFB) showing airport and route-data can support pilots. In the present study, the possibility of using a Voice Recognition System (VRS) to enable pilots to enter route instructions, for usage in situations where digital data link is not available, was investigated. The potential of techniques that utilize information on airport layout to detect and correct voice recognition errors was explored. Experiment I investigated the accuracy rates that can be achieved with the basic VRS. Although high, the resulting accuracy was insufficient, for safety reasons as well as user-acceptance of the system. A configurable system that interprets user utterances based on possible taxi routes on the airport, was designed and implemented. Experiment II explored the potential improvement of the different configuration options on error detection and correction performance. With one of the configurations, an increase of 42% in overall recognition rates was achieved.
Interference Timing and Acknowledgement Response with Voice and Datalink ATC Commands BIBAFull-Text 11-15
  Matthew R. Risser; Mark W. Scerbo; Carryl L. Baldwin; Danielle S. McNamara
Datalink is a text system used to send messages between ATC and pilots. There are concerns related to changes in information processing demands and responses associated with executing speech and text ATC commands. The timing of interference and the acknowledgement response on command execution performance were examined during the processing of simulated ATC commands. Verbal and central executive (CE) interference tasks were presented before or after the acknowledgement. Participants received both speech and text commands, responded by a verbal or manual acknowledgement, and set the controls in a flight simulator. Results demonstrated an advantage for a manual acknowledgement with longer messages. CE as opposed to verbal interference prior to an acknowledgement had a greater negative effect that was exacerbated in the text condition. The findings are interpreted within the context of a working memory and multiple-resource perspective and implications are discussed with regard to communication processes in aviation.
Comparison of Pilots' and Controllers' Conflict Resolution Maneuver Preferences BIBAFull-Text 16-19
  Esa M. Rantanen; Jiazhong Yang; Shanqing Yin
The role of the air traffic controller in future air traffic management systems is that of a passive monitor, who intervenes in potential conflict situations only if pilots, aided by onboard traffic displays, fail to implement safe and timely conflict resolutions. Yet, such scenarios are entirely plausible and even likely, particularly in busy airspaces. However, it is also likely that an a controller will seek to implement a resolution that is different from what the pilots had planned, resulting in confusion, delays, and safety risks. This paper examines pilots' and controllers' maneuver preferences and potential sources for dissonance in conflict resolution situations. Data on pilots' maneuver tendencies were gathered from an extensive review of past literature; controllers' preferences were obtained from an experiment that systematically manipulated simulated ATC scenario difficulty and conflict geometries. Results indicate largely similar maneuver choices between controllers and pilots, but suggest a need for further research.

AEROSPACE SYSTEMS: Business Case for Civil Aviation Human Factors

Business Case for Civil Aviation Human Factors BIBAFull-Text 20-24
  Paul Krois; Ulf Ahlstrom; Judith Burki-Cohen; Florian Jentsch; Barbara Kanki; Beth Lyall; Carol Manning; Ray King
We examined how human factors research and engineering in addressing flight deck and air traffic control issues improves safety and provides tangible cost savings and cost avoidance for Federal Aviation Administration sponsors and industry. The agency spends a limited percentage of its annual budget on research and prioritizes these investments to ensure the best return. This research cuts across a range of human factors considerations spanning selection of applicants for air traffic controller jobs, flight simulator fidelity, generation of scenarios used in pilot training, a new evaluation tool for flight deck certification, design of flight deck operating documents, and design of an air traffic controller information display aid.

AEROSPACE SYSTEMS: Cognitive Factors in Aviation

How Do Automation False Alarms and Misses Affect Operator Compliance and Reliance BIBAFull-Text 25-29
  Stephen R. Dixon; Christopher D. Wickens; Jason S. McCarley
Participants performed a tracking task along with a system and flight parameter monitoring task while aided by diagnostic automation. The goal of the study was to examine operator compliance and reliance as affected by automation failures, and to clarify claims regarding independence of these two constructs. Background data revealed a trend towards non-independence of the compliance-reliance constructs. Thirty-two undergraduate students performed a simulation that presented the visual display and collected dependent measures. False-alarm prone automation hurt overall performance more than did miss-prone automation, while also clearly affecting both operator compliance and reliance. Miss-prone automation only appeared to affect operator reliance.
Effects of Advanced Cockpit Displays on General Aviation Pilots' Decisions to Continue Visual Flight Rules Flight into Instrument Meteorological Conditions BIBAFull-Text 30-34
  Nicholas Johnson; Douglas Wiegmann; Christopher Wickens
Thirty pilots flew a simulated VFR cross country flight into deteriorating weather with one of three levels of display support: a control display with standard instruments, a synthetic vision system (SVS) display depicting terrain and a highway in the sky (HITS), and a configuration in which the same SVS HITS display was augmented by an electronic moving map depicting weather. Results revealed that nearly all pilots in the control condition avoided penetrating the IMC clouds. Significantly, 60% of pilots across both SVS conditions penetrated the clouds and continued to their destination in zero visibility conditions. Their failure to notice the deteriorating weather outside the cockpit was documented by a dominance of head-down scanning for the pilots in these two groups who penetrated the weather. The presence of the moving map weather display did not mitigate these manifestations of attentional tunneling. Possible solutions related to display design and training are discussed.
Examining the Viability of the Neisser Search Model in the Flight Domain and the Benefits of Highlighting in Visual Search BIBAFull-Text 35-39
  Ashley Nunes; Christopher Wickens; Shanquin Yin
We conducted four experiments to examine the visual search capability of pilots and examine how search times could be reduced, invoking the framework of Neisser's serial self terminating (SST) search model. In Experiment 1 which manipulated target presence and set size, our results show increases in response time as array size increases: an effect predicted by the SST model. In Experiment 2, we manipulated the background against which the visual search had to be performed. We found that the detrimental effects of array size on visual search time are maximal when the search is performed against maps, which have large quantities of terrain information. In Experiment 3, we sought to assess the degree to which high and low-lighting could be used to reduce the search times of pilots. We observed that although both high and low lighting reduced the search times of pilots, the observed reductions were not predicted by the SST model. The advantage of highlighting elements of the target was shown in Experiment 4.
Impact of the Use of Techniques and Situation Awareness on Pilots' Procedure Compliance BIBAFull-Text 40-44
  Steven J. Landry; Julie A. Jacko
In two empirical studies using desktop flight simulators, pilots were monitored while following procedures. In both experiments, pilots demonstrated a high degree of reliance on rule-based heuristics for following procedures (techniques), rather than on the procedures themselves. This was true regardless of the resulting compliance with the procedure. Changes to the procedure and changes to the content of displayed information had no effect on the use of techniques. In addition, frequent instances of noncompliance to procedure were recorded. The most common types of noncompliance, technical failures in implementing the procedure, were found to be nearly all innocuous, while failures related to a lack of situation awareness comprised the bulk of unsafe instances of noncompliance. Also found were a number of instances of noncompliance which actually enhanced the safety of the procedure. The results have implications for the design of procedures and for automated aids for procedure following.
An Analysis of Preflight Weather Briefings BIBAFull-Text 45-49
  O. Veronika Prinzo
Weather plays a factor in general aviation (GA) accidents and mishaps. This study documented the types of weather information that GA pilots requested and received from automated flight service stations (AFSS), and how this information might influence flight planning and weather-based decisions. An analysis was performed on 306 GA pilot telephone conversations with AFSS preflight specialists. Approximately 78% of the pilots requested a preflight briefing and specialists relayed these items: Weather synopsis, sky conditions, visibility, weather at the departure, en route, and destination point. In 15.4% of the calls, pilots declined preflight weather briefings but AFSS still relayed weather synopsis and sky conditions in addition to weather conditions that might be significant during flight. Whether by requesting additional information or receiving weather information, 31 pilots decided to change their flight plans. Surprisingly, 27% of the pilots when told 'VFR Flight Not Recommended' filed a VFR flight plan anyway.

AEROSPACE SYSTEMS: Workload & Training

The Effect of Air Traffic Increase on Controller Workload BIBAFull-Text 50-54
  Sehchang Hah; Ben Willems; Randy Phillips
The Federal Aviation Administration (FAA) has been increasing the National Airspace System (NAS) capacity to accommodate the predicted rapid growth of air traffic. One method to increase the capacity is reducing air traffic controller workload so that they can handle more air traffic. It is crucial to measure the impact of the increasing future air traffic on controller workload. Our experimental data show a linear relationship between the number of aircraft in the en route center sector and controllers' perceived workload. Based on the extensive range of aircraft count from 14 to 38 in the experiment, we can predict en route center controllers working as a team of Radar and Data controllers with the automation tools available in the our experiment could handle up to about 28 aircraft. This is 33% more than the 21 aircraft that en route center controllers typically handle in a busy sector.

AEROSPACE SYSTEMS: WorkLoad & Training

Testing Boeing's Flight Deck of the Future: A Comparison Between Current and Prototype Autoflight Panels BIBAFull-Text 55-58
  L. Ricardo Prada; Randall J. Mumaw; Deborah A. Boehm-Davis; Daniel J. Boorman
Operational issues with the current generation of flight control panels in modern airliners are well documented, and include opaque operating modes, limited feedback when modifying settings, and inconsistent interactions that can result in unexpected aircraft behaviors, leading to costly training programs. Boeing engineers have proposed a redesigned panel known as the Flight Deck of the Future (FDF), in an attempt to address these issues.
   In the first experimental test of this new interface, we studied the effects of the redesign on transfer of initial training. Tasks known to present challenges in the current generation of aircraft were selected for training and testing. Airline pilots were asked to perform these tasks on both the FDF panel, and the corresponding panel on a typical large commercial aircraft. Training transfer was found to be substantially improved on the FDF system. Implications for continued design, adoption, and airline training of the new interface are discussed.

AEROSPACE SYSTEMS: Workload & Training

Instrument Pilot Skill Acquisition in the Early Phases of Flight Training Using an Advanced Cockpit Display System BIBAFull-Text 59-62
  Steve Hall; Erin Alves
The purpose of this study was to evaluate the learning curve associated with complex flight behavior (i.e. instrument approaches) for both conventional and SVS display systems. Thirty student pilots who had not yet earned their private pilot license were presented with minimal information about instrument approaches and were trained to fly a precision approach using either the SVS or conventional display. Flight performance, measured by time within the FAA ATP standard across training trials, was significantly higher in the SVS condition for the first trial and during the three performance trials. Log function learning curves show faster learning in the SVS condition than the conventional condition. Differences in learning curves have implications for the development of training curricula, certification guidelines, and training/operations costs.
Using the Distribution of Eye Fixations to Assess Pilots' Mental Workload BIBAFull-Text 63-65
  Francesco Di Nocera; Marco Camilli; Michela Terenzi
Based on previous research showing the usefulness of spatial statistics in detecting randomness in the distribution of eye fixations, this study investigated the ocular behavior of professional pilots engaged in a simulated flight. The distribution of eye fixations is here used an index of mental workload. Eye movements were recorded during the different phases (departure to landing) of a simulated flight, and were analyzed using spatial statistics algorithms. Results showed sensitivity of spatial dispersion indices to variations in mental workload: higher during departure and landing, lower during the other phases. This result provides additional evidence of the utility of fixations distribution as a real-time measure of mental workload and, consequently, as a trigger for adaptive automation.
Sleep, Sleepiness, Fatigue, and Vigilance in a Day and Night Inspection Task BIBAFull-Text 66-70
  Colin G. Drury; Brian D. Green; Jingnong Chen; Elizabeth L. Henry
An experiment was performed to test the effects of fatigue factors on performance and stress in a high fidelity simulation of a fluorescent penetrant inspection of aircraft turbine engine blades. Five factors predicted to be potentially related to inspection fatigue were tested in a mixed experimental design using 80 participants recruited from the local community. Many main effects and interactions were significant in performance analyses, although the vigilance decrement was not a strong effect in this task. Particular significant effects are shown, plus an analysis of probability of detection as a function of crack size and contrast, relating this study to the literature on non-destructive inspection reliability.

AEROSPACE SYSTEMS: Perceptual Factors in Aviation

Using Relative Position and Temporal Judgments to Assess the Effects of Texture and Field of View on Spatial Awareness for Synthetic Vision Systems Displays BIBAFull-Text 71-75
  Matthew L. Bolton; Ellen J. Bass; James R. Comstock
Synthetic Vision Systems (SVS) depict computer generated views of terrain surrounding an aircraft. In the assessment of textures and field of view (FOV) for SVS, no studies have directly measured the 3 levels of spatial awareness: identification of terrain, its relative spatial location, and its relative temporal location. This work introduced spatial awareness measures and used them to evaluate texture and FOV in SVS displays. Eighteen pilots made 4 judgments (relative angle, distance, height, and abeam time) regarding the location of terrain points displayed in 112 5-second, non-interactive simulations of a SVS heads down display. Texture produced significant main effects and trends for the magnitude of error in the relative distance, angle, and abeam time judgments. FOV was significant for the directional magnitude of error in the relative distance, angle, and height judgments. Pilots also provided subjective terrain awareness ratings that were compared with the judgment based measures. The study found that elevation fishnet, photo fishnet, and photo elevation fishnet textures best supported spatial awareness for both the judgments and the subjective awareness measures.
Ice Detection Capabilities Under Aircraft Post Deicing Conditions BIBAFull-Text 76-80
  Edmundo A. Sierra; Kimberlea Bender; Isabelle Marcil; John D'Avirro; Edward Pugacz; Frank Eyre
Human visual and tactile ice detection capabilities while inspecting deiced aircraft surfaces have not been quantified. Six male professional deicers from AeroMag 2000 Montreal participated in the experiment. We used a cold chamber to simulate one of the conditions experienced in the operational deicing environment. Ice samples were created by APS Aviation on white painted aluminum panels. Ice thicknesses ranged from 0.2 mm to 1.0 mm and were covered with aircraft deicing fluid. We used a two-alternative forced-choice procedure in which we showed a deicer a panel, then a second panel, and finally asked him to indicate on which of the two ice was present. Our data showed that, within the range of thicknesses we presented, deicers were unable to visually detect ice of any thickness on the white painted panels, but could easily detect ice using a tactile check.
Integrated Hazard Displays: Individual Differences in Visual Scanning and Pilot Performance BIBAFull-Text 81-85
  Army L. Alexander; Christopher D. Wickens
Synthetic vision systems, of which integrated hazard displays may be an integral component, are being developed to allow for safe and efficient navigation through terrain-challenging or low-visibility conditions. In this study, 24 pilots flew a series of approaches while maintaining their position within a highway in the sky and responding to periodic queries regarding traffic location as represented within the integrated hazard display. Eye-movement data were examined to determine the effects of visual scanning behaviors on pilot performance (flight control, traffic awareness, and off-normal event detection). Overall, all pilots treated the flight task of aviating as primary, giving it the attentional resources required to maintain adequate performance. While scanning patterns were relatively equivalent between the off-normal event detection groups, the detectors did not appear to be as attentionally tunneled to the compelling SVS suite as the non-detectors, given that they were able to notice and respond to the non-database tower visible only in the outside world. In fact, pilots who failed to detect the off-normal event spent less time scanning the outside world on the relevant trial, where the ground truth information was represented. The results are interpreted within a task management framework mediated by performance resource functions.
Night Vision Goggle External Lighting Effects BIBAFull-Text 86-90
  Greg Craig; Sion Jennings; Robert Erdos; Michel Brulotte; Macuda Todd; Stephan Carignan
The National Research Council of Canada, Transport Canada and the Federal Aviation Administration examined external lighting and night vision goggle interaction by quantifying the effects of incompatible lighting on visual acuity and recording pilot comments. Four observers and three sets of lights were tested using Landolt ring visual acuity charts created for distances of 15.2, 30.5 and 45.7 m. NVG compatible external lights provided consistent acuity scores in a symmetrically lit visual field. Acuity scores varied greatly with incompatible lights that caused an asymmetric viewing field. Implications for civil NVG operations are discussed.
Utilizing Ecological Perception to Support Precision Lunar Landing BIBAFull-Text 91-95
  Cristin A. Smith; M. L. Cummings; Laura M. Forest; Lauren J. Kessler
In this paper, we introduce the motivation for and design of and integrated flight instrument display component for use during vertical landing and hover operations of a future Lunar lander to support the vision to return to the Moon. A description of the human-system interface design approach to include a cognitive task analysis is outlined. The results of the analysis and the design of the resultant precision landing aid are discussed. The proposed integrated flight instrument display component, the Vertical Altitude and Velocity Indicator (VAVI), which leverages ecological perception through emergent features, is described in detail as well as the motivation and the rationale behind its design. The applicability of the precision landing aid to the aviation domain for use in V/STOL aircraft and rotorcraft is also discussed.

AEROSPACE SYSTEMS: Human-Systems Integration Challenges for Constellation

Human-Systems Integration Challenges for Constellation BIBAFull-Text 96-100
  Jeffrey W. McCandless; Mary K. Kaiser; Timothy S. Barth; Robert S. McCann; Nancy J. Currie; Barbara J. Woolford
The National Aeronautics and Space Administration (NASA) is developing plans for the successor to the Space Shuttle. The Constellation Program within NASA is responsible for developing the Crew Exploration Vehicle (CEV) and related systems to provide astronauts with access to space. The CEV will include many improvements over previous spacecraft, and numerous NASA groups are involved in designing those improvements. For example, the Space Human Factors Engineering (SHFE) project is supporting work on a range of tasks including crew training, cockpit displays, and crew anthropometry. Additional improvements will focus on launch and landing site operations. Within the CEV itself, an upgraded caution and warning system will increase the crew's abilities to diagnose and resolve malfunctions. CEV ergonomics are critical since the vehicle will support several configurations of crew and cargo to maximize its operational flexibility. Work on CEV habitability is being based on numerous factors such as a task analysis to identify critical crew activities. All of these tasks will help ensure that the next-generation spacecraft provides safe and efficient access to space.

AEROSPACE SYSTEMS: Have a Safe Flight: A Practice-Oriented Session

Aeronautical Emergency and Abnormal Checklists: Expectations and Realities BIBAFull-Text 101-105
  Barbara K. Burian
Developers of emergency, abnormal, and non-normal checklists hold a number of beliefs about how, when, and under what types of conditions flight crews will access and use these checklists. These beliefs or expectations strongly influence the decisions developers make about checklist content, design, and presentation. Interviews with pilots involved in incidents and accidents, simulator observations, and analyses of paper and electronic checklists, reveal that many of the expectations developers hold, which are implicit in checklist designs, do not match the realities of emergency and abnormal situations and flight crew checklist use. Several of these expectations are presented along with contrasting realities and some suggested design solutions.
Design Guidance for Emergency and Abnormal Checklists in Aviation BIBAFull-Text 106-110
  Barbara K. Burian
It can be extremely challenging to develop effective checklists for use by flight crews during emergency and abnormal situations. Relatively little guidance is available from the human factors community and developers generally use aircraft system requirements, historical precedent, and their own best judgment to guide their design decisions. Through work at the NASA Ames Research Center, a model of emergency and abnormal checklist design, content, and use has been developed. This comprehensive model identifies all aspects that need to be considered and brings attention to some that are often unappreciated in emergency and abnormal checklist design (e.g., human performance limitations under stress).
Evaluation of Onboard Taxi Guidance Support on Pilot Performance in Airport Surface Navigation BIBAFull-Text 111-115
  Bernd Lorenz; Marcus Biella
Advanced Surface Movement Guidance and Control Systems (A-SMGCS) comprise a range of new technologies for both the flight deck and ground air traffic control and is supposed to enable increased safety and a more efficient throughput at presently highly congested major airports. A flight deck A-SMGCS module is the onboard guidance system TARMAC-AS. This module consists of controller pilot data link communication (CPDLC) and an electronic moving map (EMM), which also serves as a cockpit display of traffic information (CDTI). TARMAC-AS is evaluated in an investigation involving 49 commercial pilots who performed a series of approach, landing and taxiing simulation trials under varied visibility, which were completed in a fixed-base cockpit simulator. Results support the notion that an EMM + CPDLC + CDTI improve the effectiveness of taxi navigation. A potential negative impact of observed increased head-down times to the compelling TARMAC display on unexpected outside scene obstacle detection was not substantiated.
Anthropometric Standards on the Flight Deck: Origins of Control-force-exertion Limits and Comparisons with Recent Surveys of Human Performance Limitations BIBAFull-Text 116-120
  Dennis B. Beringer
Sections of the Code of Federal Regulations (14 CFR 23.143 and 25.143) contain maximum limitations on the force that a pilot can be required to exert on manual controls. The origins of the data, used for testing and certification of aircraft, are unclear. Although some values were recently modified to be congruent with European standards, the continued applicability of these standards is questionable because of the lack of information regarding their origin, changing pilot demographics (a higher percentage of women pilots, an aging pilot population and suspected changes in the overall population), and changing aircraft-control environments. The criteria were compared with several later samples to determine what portion of the potential and actual pilot populations can meet the force-application requirements. Preliminary data reported for women pilots and nonpilots were compared with previously collected data on similar populations and with the standards.

AEROSPACE SYSTEMS: Aviation at a Distance

Advanced Display Concepts for Uav Sensor Operations: Landmark Cues And Picture-In-Picture BIBAFull-Text 121-125
  Gloria L. Calhoun; Mark H. Draper; Jeremy T. Nelson; Health A. Ruff
UAV video imagery quality can be compromised by narrow field-of-view, environmental conditions, bandwidth limitations, or a highly cluttered scene. Advanced display concepts (e.g., synthetic vision) can potentially ameliorate video characteristics and enhance UAV operations. This study evaluated three display concepts for improving UAV sensor operator situation awareness: virtual flags overlaid on landmarks, a synthetically-generated imagery border (picture-in-picture), and a display-fixed spatial orientation symbol. Sixteen participants searched for ground landmarks using a UAV-mounted gimbaled camera simulation. Results indicated that the display concepts show promise for improving UAV operations. In particular, virtual flags reduced landmark search times by 40-58%. Although the picture-in-picture concept did not improve performance, comments suggest an alternative instantiation of the concept will improve utility.
Comparing two Kinematics Methods for Telerobotic Control Applications BIBAFull-Text 126-130
  Keshav K. Chintamani; Aditya K. Nawab; Abhilash K. Pandya; R. Darin. Ellis; Alex Cao; Gregory Auner
Two inverse kinematics algorithms were implemented in a tele-operated robot system and evaluated with a user performance study. The kinematics algorithms were designed such that the point of resolution (POR) of the robot arm's wrist and the end-effector was controlled by joysticks, one each for rotation and translation. Operator performance was evaluated with "peg-in-the-hole" type tasks using both the wrist and end-effector POR modes. Wrist kinematics resulted in faster performance times, however, with longer average distances traveled while the opposite effect was observed with end-effector kinematics. Reversal errors were present equally in both modes, while the end-effector mode showed higher 1-axis use of the joysticks. Implications for remote robotic operation design and kinematics are discussed.
Optimizing the Presentation of Uav Images in an Attack Helicopter Cockpit BIBAFull-Text 131-135
  Chris Jansen; Sjoerd de Vries; Maaike Duistermaat
Future Unmanned Aerial Vehicles (UAV) will collaborate more directly with military manned aircraft. TNO Defence, Security and Safety investigated how to present UAV sensor images in a fighter aircraft cockpit in order to maximize target identification and flying performance. Ten military pilots performed several Close Air Support missions in a helicopter simulator using four different display configurations. The orientation of the electronic map was either North-Up or Heading-Up. The UAV sensor image was either non-aligned (unadjusted image orientation: the image is presented as seen from the UAV viewpoint), or aligned with the orientation of the electronic map (adjusted image orientation, either resulting in a North-Up orientation or a Heading-Up orientation with respect to the helicopter, depending on the orientation of the electronic map). The pilots reported that they generally preferred the aligned UAV sensor image in combination with a Heading-Up map. This preference was reflected in their performance: targets were identified twice as fast, and the waypoint trajectory was flown more efficiently.
Evaluation of an Advanced Fault Management System Display for Next Generation Crewed Space Vehicles BIBAFull-Text 136-140
  Miwa Hayashi; Valerie Huemer; Joel Lachter; Dorion Liston; Steve Elkins; Fritz Renema; Brent Beutter; Jeffrey W. McCandless; Robert S. McCann; Lilly Spirkovska
The next generation Crew Exploration Vehicle is planned to employ Integrated Systems Health Management (ISHM) technology to enhance crew safety and improve onboard operations. For example, the ISHM could assist crewmembers with real-time fault management operations by automatically identifying the root cause of complex system malfunctions. However, to implement such a system, several human-factors issues have to be addressed. For instance, human-machine functional allocations have to be made and supporting crew interfaces designed and evaluated. The paper describes a concept for crew-ISHM interactions called the Fault Management Support System (FAMSS) that addresses these human-factors issues. Simulator experiment results showed that a simulated FAMSS interface improved operators' situation awareness and fault-management performance while decreasing fault-management workload.
The Importance of Determining Individual Operator Capabilities When Applying Adaptive Aiding BIBAFull-Text 141-145
  Glenn F. Wilson; Christopher A. Russell; Iris Davis
Performance was significantly improved in an Uninhabited Air Vehicle (UAV) task when individually determined task difficulty levels were used to present psychophysiologically controlled adaptive aiding. Previous research in our laboratory demonstrated that the benefit of adaptive aiding varied according to the operator's skill level when a common task difficulty was used for all operators. In the present study the difficult task level was determined for each operator. An average task difficulty level was also used. The best performance occurred when adaptive aiding was presented based upon psychophysiological data submitted to an artificial neural network when the implementation level was individually determined for each operator. Performance improvement using the mean difficulty level was lower as were the results when the adaptive aiding was randomly presented. Individual cognitive capability must be considered to achieve optimal performance via adaptive aiding.

AEROSPACE SYSTEMS: Distributed Simulation of ROVs Flying in Terminal Airspace

Recommendations for Conducting Real-Time Human-in-the-Loop Simulations Over the Internet BIBAFull-Text 146-150
  Thomas Z. Strybel; Riva Canton; Vernol Battiste; Walter Johnson; Kim-Phuong L. Vu
Distributed simulations can improve the cognitive fidelity of simulated task environments because more operators can be added to the simulation without greatly increasing its cost. We report here on the development and execution of a distributed simulation/demonstration of ROVs flying in terminal airspace in order to investigate the feasibility of ROV flight in terminal airspace, and the feasibility of conducting simulations over the internet. The simulation involved pilots located at CSAAT, an aviation research lab at California State University Long Beach, and the Flight Deck Display Research Laboratory at NASA Ames Research Center, flying ROVs over the internet in a simulated airspace. We describe the procedures used to develop the simulation and offer recommendations for improving future simulations over the internet.
Pilot Performance Controlling Multiple Rovs in Terminal Airspace and Strategies for Managing Them BIBAFull-Text 151-155
  Kim-Phuong L. Vu; Marshall Dion; Vanessa Chambers; Thuan K. Ngo; Deborah Nelson; Jerome Kraft; Thomas Z. Strybel
This paper is based on a demonstration of a distributed simulation conducted between the Flight Deck Display Research Laboratory (FDDRL) of NASA Ames Research Center and the Center for the Study of Advanced Aeronautic Technologies (CSAAT) at California State University, Long Beach. Simulated ROVs were flown in terminal airspace for the purpose of determining the feasibility of flying ROVs through commercial traffic. Pilots, with glass cockpit experience, were required to fly one or two ROVs in simulated airspace over water reservoirs near DFW airport, with the major goal of avoiding the approach traffic while patrolling Grapevine and nearby lakes. This paper will focus on pilot performance and strategies for controlling single versus multiple ROVs. Results showed that pilots had a difficult time patrolling the lake without losing separation from the approach traffic. However, their performance did improve after practice. Cooper-Harper workload ratings showed that pilots experienced higher workload when controlling two ROVs compared to one, especially in high traffic, which matches the performance data. Strategies for control of multiple ROVs are discussed.
So you Want to Fly Remotely Operated Vehicles in Civil Approach Air Space BIBAFull-Text 156-160
  Vernol Battiste; Arik-Quang V. Dao; Thomas Z. Strybel; Marshall Dion; H. Bertolotti
A distributed simulation was conducted between the Flight Deck Display Research Laboratory (FDDRL) of NASA Ames Research Center and the Center for the Study of Advanced Aeronautic Technologies (CSAAT) at California State University, Long Beach to assess the feasibility of flying ROVs in busy terminal environments with commercial traffic. Pilots with glass cockpit experience were recruited to fly one or two ROVs in simulated airspace over water reservoirs near DFW airport, with the major goal of avoiding the approach traffic. Results showed that pilots had a difficult time patrolling the lake without losing separation from the approach traffic. However, their performance did improve with practice. The commercial pilots' performance in our study suggested that ROV operations in busy terminal airspace were feasible and that they would be comfortable operating in the airspace jointly with ROVs. Strategies for control of a single or multiple ROVs are discussed.
Evaluation of the Usefulnes and Usability of Cockpit Situation Display Perspectives for Rov Operations in Approach Civil Air Space BIBAFull-Text 161-165
  Arik-Quang V. Dao; Vernol Battiste; Stacie Granada-Vigil; Walt W. Johnson
A distributed simulation of ROV operations was conducted by NASA Ames Flight Deck Display Research Laboratory (FDDRL) and the Center for Aeronautic Technologies (CSAAT) at California State University, Long Beach. The goals of this simulation were 1) to examine ROV operators' ability to maintain standard terminal separation from other aircraft and ROVs, 2) to examine the possibility of operating ROVs in terminal airspace without major disruptions in the inbound traffic flows, and 3) to evaluate proposed ROV operator tools. The current paper focuses on this third goal. Specifically the paper describes the motivation behind the development of the manipulatable 2D/3D Cockpit Situation Display (CSD), and examines its usefulness and usability. Data from questionnaires, and from observations of how the CSD was used, suggest that both the CSD format, and the ability to manipulate the CSD viewing angle, were useful and usable. However, workload appeared to play an important role in the perceived usefulness and usability of the CSD.

AEROSPACE SYSTEMS: Human Factors of Remotely Operated Vehicles

Human Factors of Remotely Operated Vehicles BIBAFull-Text 166-169
  Nancy J. Cooke
From Hurricane Katrina to the war in Iraq and US border security, ROVs (Remotely Operated Vehicles) are taking a front seat. They can do work that is beyond human capabilities or that puts humans in harm's way. However, the fact that there are no humans in the vehicle is misinterpreted by some as no humans in the system. On the contrary, ROVs are complex systems that require much human involvement. There are many human factors issues ranging from remote control and soda straw displays to spatial disorientation and automation. Further, there are significant mishaps with a large portion attributed to human factors issues. This panel will describe the state-of-the art in human factors of ROVs through some examples of research in the area. In addition panelists will interact with the audience and address questions centering on the challenges, the constraints, and the successes of human factors considerations for ROVs.

AGING: A1 - Aging in the Real World: Practical Research Applications

Medication Adherence Strategies in Older Adults BIBAFull-Text 170-174
  Julie B. Boron; Wendy A. Rogers; Arthur D. Fisk
Medical advancements, including medications to manage disease, have contributed to increased longevity. Because medical products contribute to increased longevity, medication adherence is important for the older adult population. Proper adherence not only contributes to quality of life physically, but also to decreased health care costs. Effective support systems to facilitate maintenance of medication regimens are necessary. Knowledge of the popularity of strategies employed by older adults can inform the design of support systems. In a survey of 366 adults aged 60 to 80 we found that older adults use multiple strategies, and these strategies are most effective when in their normal routine. Thus support systems should incorporate and facilitate the use of multiple strategies. Moreover, support systems are needed for adherence to medication regimens when people are outside of their routines.
Videoconferencing Technology As Environmental Support for Older Adults BIBAFull-Text 175-179
  Tiffany S. Jastrzembski; Roy W. Roring; Neil H. Charness
Age-related declines in cognitive abilities can sometimes be remedied for working memory intensive tasks by providing what Craik (1986) termed "environmental support," for instance, using external memory cues to alleviate normal memory retrieval demands. We investigated a way-finding task that requires serial recall, a particularly challenging memory task for older adults. We compared videoconference versus voice-only guided presentation of routes to younger and older adults. Participants viewed or did not view maps containing the to-be-learned routes. Additionally, participants were allowed to take notes to simulate real-world situations more closely for half of the trials. Analyses indicate an interaction of age, notes, and map presentation at recall, suggesting environmental support from videoconferencing reduces the advantage of note taking for older adults. Videoconferencing can be a particularly effective presentation medium for older adults with respect to memory-intensive everyday tasks.
Benefits and Privacy Concerns of a Home Equipped With a Visual Sensing System: a Perspective from Older Adults BIBAFull-Text 180-184
  Kelly E. Caine; Arthur D. Fisk; Wendy A. Rogers
Monitoring technology has the potential to allow older adults to remain in their homes longer than may otherwise be possible. However, often this monitoring technology captures images which may cause privacy concerns, especially when these images are captured in a home environment. We used Likert scales within a structured interview to investigate privacy concerns in an aware or smart home environment. Specifically, we were interested in how the type of image that was captured and the level of functioning of the person being monitored affected privacy concerns in a home environment. The data suggest that both device type as well as level of functioning affect privacy concerns in a variety of situations, providing the first evidence that certain privacy concerns are not independent of situation variables.
The Effects of Age and the Design of Web-based Training on Computer Task Performance BIBAFull-Text 185-189
  Sharnnia Artis; Brian M. Kleiner
Given the use of computers in the workplace and homes and the increase in the number of older adults in the next 20 years, the use of computers by older adults is a significant issue that should be addressed (Czaja, 1996). Due to the decline in cognitive skills as individuals age, deficits in working memory can place older adults at a disadvantage when performing computer-interactive tasks (Salthouse, 1996). The objective of this study was to explore performance differences between younger adults (18-23 years old) and older adults (63-83 years old) being taught a computer task using a web-based training program. This study concluded that age-related differences were evident in training time, task completion time, and performance score. Results were discussed in terms of limitations and implications of older-adult centered training programs.

AGING: A2 - Aging, Cognition, and Abilities

Queuing Network Modeling of Age Differences in Driver Mental Workload and Performance BIBAFull-Text 190-194
  Changxu Wu; Yili Liu
Modeling and predicting age differences in driver mental workload and performance may help the invehicle system design to reduce or prevent information overloading on older drivers. However, few computational models exist that account for age differences in mental workload. We propose a new computational modeling approach to model workload and performance -- a queuing network approach based on queuing network theory of human performance (Liu, 1996, 1997) and neuroscience discoveries. This modeling approach is composed of a simulation model of a queuing network architecture and a set of mathematical equations implemented in the simulation model to quantify the age differences. The model successfully accounts for the age differences in mental workload and performance between young and older drivers in an experimental study in driving. Further usage and implementation of this model in designing adaptive in-vehicle systems to assist older drivers are discussed.
What Factors Other Than Age Predict Performance on an Information Search Task? BIBAFull-Text 195-199
  Sara J. Czaja; Joseph Sharit; Sankaran N. Nair
The number of workers aged 55+ will increase significantly in the next few decades. This paper examines factors such as cognitive abilities and prior computer experience that influence performance and job satisfaction on a simulated email-based customer service task among a sample of older adults. Fifty-two persons ranging in age from 50-80 performed the task for four days post-training. The participants also completed a cognitive battery, computer experience questionnaire, and measures of workload, intrinsic job satisfaction and intrinsic job motivation. The data indicated performance was influenced by prior computer experience, cognitive abilities and age such that those with less experience, lower abilities and who were older performed the task at lower levels. Job satisfaction was influenced by perceptions of workload, interest in computers and intrinsic job motivation. Generally people who rated workload higher and who had higher intrinsic motivation and greater interest in computers were more satisfied performing the task.
Impact of Auditory and Visual Distractors Upon Manual Assembly Task Learning Among Older Workers with Different Levels of Spatial Reasoning And Field Dependence BIBAFull-Text 200-204
  S. F. Wiker; Diana Schwerha; Majid Jaraiedi
We examined the impact of age upon learning a manual assembly task in the presence of visual and auditory distractors in males and females ranging in age between 18 and 65 years. Task learning, as measured by time to asymptote as well as error rate. Both metrics were affected by distractors when both auditory and visual distraction loads were present, and only in older subjects who possessed low spatial reasoning ability. Older subjects who possessed excellent spatial reasoning capability performed competitively with younger subjects. Recommendations for use of spatial reasoning and field dependence in future aging-related psychomotor task learning research are provided and practical use of these findings are discussed.
Aging and Visual Attention: The Effect of Perceptual Load on Dual-task Performance BIBAFull-Text 205-209
  Richard Pak; Wendy A. Rogers; Arthur D. Fisk
The ability to use information that is not directly in front of us (information located in the periphery) is important in many aspects of everyday life (e. g., using a computer, driving). It may be critical that a person be able to effectively use the information in the periphery. The current study examined how age-related changes in perceptual processing capacity and display-related variations in perceptual load affected the spatial distribution of visual attention. The results suggest that displays that make high demands on perceptual processing capacity reduce the functional field of view in older adults. Younger adults, however, were unaffected by the perceptual load manipulation. The primary practical implication is that displays that are intended to be used by older adults should not make high demands on their limited perceptual processing capacity.

COGNITIVE ENGINEERING AND DECISION MAKING: Automation Reliability and Trust

Imperfect Diagnostic Automation: An Experimental Examination of Priorities and Threshold Setting BIBAFull-Text 210-214
  Christopher D. Wickens; Stephen R. Dixon; Nicholas Johnson
Diagnostic automation, such as alarms, alerts, or automatic target recognition systems can vary in their reliability and threshold setting, the latter influencing the balance between misses and false alarms. This experiment examined the implications of both of these, when the system detected military targets in parallel with the human operator in an unmanned air vehicle simulator. Unlike previous investigations of this paradigm in a dual task setting, the automation diagnosis task was very difficult, and priority between this task and a concurrent task was explicitly varied, along with the threshold setting. The results revealed that: (a) reliability as low as 0.6 aided human performance. (b) the effects of the automation threshold shift could be partially modeled in terms of the classic reliance-compliance dimensions of automation dependence, at both task priority settings. (c) The priority effects were more pronounced with miss-prone automation. (d) directing attention to false-alarm prone automation actually degrades human-system performance.
Effect of Shared Information on Trust and Reliance in a Demand Forecasting Task BIBAFull-Text 215-219
  Ji Gao; John D. Lee
People have difficulty relying on forecasting systems appropriately, which can lead to huge business losses. Sharing information regarding the performance of forecasting systems may lead to more appropriate trust and reliance. This study considered imperfect forecasting systems and investigated how sharing such information influences people's trust and reliance. A simulated demand forecasting task required participants to provide an initial forecast, select and view a model forecast, and then determine their final forecast. Results showed that participants' reliance on a forecasting model strongly depended on their trust in the model, which was often inappropriate. With shared information, participants' reliance was more sensitive to changes of their trust in the model. However, when the shared information exposed instances of poor performance of the model, it diminished compliance with the selected model forecast, which undermined the accuracy of the final forecasts. These results suggest that sharing information may promote more appropriate reliance in situations in which people over trust automation, but not in situations in which people tend to under trust automation.
Misuse of Automated Aids in Process Control: Complacency, Automation Bias and Possible Training Interventions BIBAFull-Text 220-224
  Dietrich Manzey; J. Elin Bahner; Anke-Dorothea Hueper
One important aspect of automation misuse is reflected in an inappropriate monitoring or checking of automated functions, a phenomenon that commonly has been referred to as complacency. The present study investigates complacency effects in interaction with an automated aid in a process control simulation task, as well as its possible performance consequences, i.e. automation bias in terms of commission errors, and impairments of return-to-manual-performance in case of automation breakdown. Furthermore, the effect of a specific training intervention to reduce complacency by exposing participants intentionally to automation failures is investigated. The results provide clear evidence for complacency effects, reflected in an insufficient verification of recommendations provided by the automated aid. Yet, only very high levels of complacency were associated with commission errors, i.e. following an automated advice although it actually is wrong. Exposing operators intentionally to automation failures during training significantly reduced the complacency effect but did not prevent it completely.
Under-Reliance on the Decision Aid: A Difference in Calibration and Attribution Between Self and Aid BIBAFull-Text 225-229
  Kees van Dongen; Peter-Paul van Maanen
It is often assumed that two heads are better than one, but reliance on decision aids is often inappropriate. Decisions to rely on an aid are thought to be based on a comparison between the perceived reliability of own performance and that of the decision aid. Unfortunately, perceived reliabilities are unlikely to be perfectly calibrated. This may result in inappropriate decisions to rely on advice. In a laboratory experiment with 40 participants, we studied whether calibration improves after practice, whether calibration of own reliability differs from calibration of the aid's reliability and whether unreliability of the aid is attributed differently. Under-trust in own reliability disappears after practice but under-trust in the aid's reliability persists. Unreliability of the decision aid is less likely to be attributed to temporary, external and uncontrollable factors. This asymmetry in attribution and calibration may explain under-reliance on decision aids.
Expertise Levels of Human Versus Automated Decision Aids Influence Response Biases in a Visual Search Task BIBAFull-Text 230-234
  Poornima Madhavan; Douglas A. Wiegmann
Studies have demonstrated that humans appear to apply norms of human-human interaction to interaction with automated decision aids. We examined the differences in perceptions of automation vs. humans when the expertise and reliability of these advisers varied. Participants (n = 180) performed a luggage-screening task with the assistance of human or automated advisers that differed in pedigree (expert vs. novice) and reliability (high vs. low), but had a similar neutral beta setting of 1.0. Shifts in sensitivity, criterion settings and accuracy were assessed. Participants who were presented with a low-reliable "expert" adviser shifted their bias away from the neutral bias of the adviser and more toward optimal beta compared to participants receiving unreliable advice from a 'novice'. This effect increased across trials for participants using low-reliability automated advisers but not human advisers. The results have implications for the development of models of optimal utilization of decision aids.

COGNITIVE ENGINEERING AND DECISION MAKING: Bridging the Gap from Analysis to Design

Generating Requirements for Futuristic Hetrogenous Unmanned Systems BIBAFull-Text 235-239
  Carl E. Nehme; Stacey D. Scott; M. L. Cummings; Carina Yumi Furusho
A cognitive task analysis (CTA) is an effective analysis technique for deriving design requirements for many task domains. However, traditional CTA approaches have limited applicability to futuristic systems because CTA approaches generally require access to subject matter experts, documentation, and previous implementations from which to draw assumptions and expertise. In this paper, we introduce a hybrid CTA framework that allows the generation of information and display requirements for futuristic systems for which no current implementations exist. This analysis technique involves a four-step process including: 1) generating a scenario task overview, 2) generating an event flow diagram, 3) generating situation awareness requirements, and 4) creating decision ladders for critical decisions. We demonstrate the effectiveness of this process through a case study in which functional and interface requirements are generated for the supervisory control of multiple, heterogeneous unmanned vehicles.
Using Work-Centered Specifications to Integrate Cognitive Requirements into Software Development BIBAFull-Text 240-244
  Jeffrey Wampler; Emilie Roth; Randall Whitaker; Kendall Conrad; Mona Stilson; Gina Thomas-Meyers; Ronald Scott
As Cognitive Engineering (CE) becomes mainstream, methods are needed to better integrate the unique cognitive requirements of the target users of a Human Computer Interface (HCI) into software development requirements and testing. This paper discusses a preliminary work-centered specification describing the key cognitive HCI elements of a complex work system that enhance situation awareness (SA) and decision making. The specification provides traceability from the cognitive requirements obtained during knowledge acquisition to specific display elements in the final design. This specification approach can be applied to any CE methodology. We are applying it to a working prototype currently being integrated into an operational system. We have elicited feedback from developers of the operational system regarding the content and usefulness of the specification as it applies to their software development processes. This paper highlights critical aspects of our inaugural work-centered specification.
Numerical Models in Representation Design: Computing Seawater Properties in an Ecological Interface BIBAFull-Text 245-249
  Nathan Lau; Greg A. Jamieson
The contribution of cognitive engineering in complex systems is often limited by the availability of information to populate advanced representational forms, such as those characterized by the Ecological Interface Design framework. We suggest the application of numerical models to derive required information, supplementing the analytical methods that are commonly used in computational aiding. We demonstrate the approach by presenting a solution combining numerical and analytical methods to the problem of determining seawater properties in a nuclear power plant. The example demonstrates that numerical approaches can expand the range of possible applications of representation aiding in complex systems.
A Framework for Considering Spatial-Temporal Representation Design in Air Traffic Control BIBAFull-Text 250-254
  B. L. William Wong; Simone Rozzi; Paola Amaldi; Peter Woodward; Bob Fields
In this paper we present a framework for considering the design of information visualisations intended to support 4D or spatial-temporal reasoning in Air Traffic Control. The Spatial-Temporal Framework was developed based on a cognitive task analysis of approach controllers. This work was conducted as part of a to develop a novel 4D interface for a possible future ATC system. A 4D interface is one that incorporates the visualisation of 3D space and time. The framework allows us to identify the spatial properties of a tactical ATC situation: objects, constraints and relationships; and how they are affected by the temporal attributes of the past, present, projected and intended actions. It is envisaged that this framework can provide guidance for our consideration and analytic assessment of new visualisation designs for a 4D interface.
Work-Centered Design and Evaluation of a C2 Visualization Aid BIBAFull-Text 255-259
  Emilie Roth; Mona Stilson; Ronald Scott; Randall Whitaker; Tom Kazmierczak; Gina Thomas-Meyers; Jeffrey Wampler
Command and Control (C2) operators increasingly need to assimilate large amounts of near-real time data distributed across multiple sources to identify, interpret, and mentally fuse the information necessary to accomplish their work. We have been developing and applying work-centered design and evaluation methodologies to design advanced visualization and support tools intended to more effectively support C2 cognitive and collaborative work. The paper reports the results of a work-centered evaluation assessing the usability and usefulness of an innovative work-centered visualization aid (a graphic mission timeline display) we developed to support mission replanning during execution in a C2 airlift service. The evaluation compared performance with the work-centered visualization to performance using the existing information technology system. The work-centered visualization produced statistically significant improvement in task completion time, errors, workload and situation awareness. The results point to the value of taking a work-centered analysis and design approach.

COGNITIVE ENGINEERING AND DECISION MAKING: Situation Awareness in Complex Domains

Distributed Situation Awareness in Command and Control: A Case Study in the Energy Distribution Domain BIBAFull-Text 260-264
  Paul M. Salmon; Neville A. Stanton; Guy H. Walker; Chris Baber; Richard McMaster; Dan Jenkins; Ajay Beond; Omar Sharif; Laura Rafferty; Darshna Ladva
Distributed Situation Awareness (DSA), in terms of structure and knowledge content, distribution, sharing and usage, has important implications for command and control infrastructure design, network configuration, performance and efficiency. Despite this, theory and methods for evaluating DSA in complex sociotechnical systems are currently lacking. This article presents a novel methodology for assessing DSA, along with a case study of DSA in the energy distribution domain. The Event Analysis of Systemic Teamwork (EAST) methodology was used to analyse three scenarios undertaken on a major UK electricity distribution network. In conclusion, an analysis of propositional knowledge networks indicated that DSA effectively 'coupled' the command and control networks observed. DSA comprised 'activated' knowledge objects that were held by, and shared between, the agents involved. Further, analysis of knowledge usage indicated that each agent involved possessed disparate but complementary levels of situation awareness during task performance.
Feedforward Effects on Predictions in a Dynamic Battle Scenario BIBAFull-Text 265-269
  Cleotilde Gonzalez; Michael Martin; Jeffrey T. Hansberger
Commanders face many challenges in their efforts to control the battlefield. Friction (i.e., sources of delay) in the commander's control system, coupled with the dynamics of the battlefield, requires commanders to act before threatening battlefield events occur. Effective control of the battlefield thus requires accurate predictions. This paper describes the results of a preliminary study concerned with the effect of FeedForward (FF) on the accuracy of predictions in dynamic battle situations. FF, given in the form of expert advice prior to simulated battle, did not reliably improve predictions. Exploratory analyses, however, indicate that FF guided attention to a subset of the task variables important for accurate prediction. Furthermore, FF produced quicker and more decisive victories than practice alone. In conjunction with the positive performance trend for the FF group, these findings indicate that FF facilitates strategy development and may lead to higher levels of Dynamic Decision Making (DDM) performance over time.
Situation Awareness and Driving Performance in a Simulated Navigation Task BIBAFull-Text 270-274
  Ruiqi Ma; David B. Kaber
This study investigated the effect of varying reliability of in-vehicle navigation aids on driver situation awareness (SA) and performance. Twenty participants drove a virtual car and navigated a large virtual suburb. Participants were required to follow traffic signs and navigation directions from one of two sources: a human aid via a cell phone or an automated aid presented on a laptop display. The aids operated under three different levels of reliability (100%, 80% and 60%). A control condition was also used in which each aid presented a telemarketing survey and participants navigated using a map. Results revealed perfect navigation information to improve driving performance and SA for strategic behaviors, as compared to unreliable information and the control condition. This work demonstrates in-vehicle automation may mediate linkages of levels of SA to specific driving behaviors and associated actions. This is represented through a transactional model of driver SA.
Towards a Sensitive Measure of Situation Awareness in Adaptively Automated Systems BIBAFull-Text 275-279
  Christopher K. McClernon; David B. Kaber; Carlene M. Perry; Noa Segall
The objective of this research was to assess the effectiveness of the Situation Awareness Global Assessment Technique (SAGAT) as an indicator of automation state changes in adaptive automation (AA) of a complex, dynamic control task. An air traffic control (ATC)-related simulation was developed to present automation of four different information processing (IP) functions, including information acquisition, information analysis, decision making, and action implementation, as well as to simulate a completely manual control condition. Eight participants operated the ATC simulation under the five conditions. SAGAT data revealed only a general effect of automated versus manual control, but no significant effects of the modes of AA on SA. These results suggested that SAGAT was not a sensitive measure in the ATC-related task. Consequently, a modified SAGAT measure is proposed with relevance weighting of environmental stimuli to promote sensitivity and reliability of measurement of SA in the target domain.
Efficacy and Acceptance of Driver Support Under Possible Mismatches Between Driver's Intent and Traffic Conditions BIBAFull-Text 280-283
  T. Inagaki; M. Itoh; Y. Nagai
This paper tries to answer the following question: What type of support should be given to an automobile driver when it is determined, via some method to monitor the driver's behavior and the traffic environment, that the driver's intent may not be appropriate to a traffic condition? With a medium fidelity, moving-based driving simulator, three conditions were compared: (a) Warning type support in which an auditory warning is given to the driver to enhance his/her situation recognition, (b) action type support in which an autonomous safety control action is executed to avoid an accident, and (c) the baseline condition in which no driver support is given. Results were: (1) Either type of driver support was effective in accident prevention. (2) Acceptance of driver support functions varied context dependently. (3) Participants accepted a system-initiated automation invocation as long as no automation surprises were possible to occur.

COGNITIVE ENGINEERING AND DECISION MAKING: Collaborative Decision Making in Network-Centric Military Operations

Collaborative Decision Making in Network-Centric Military Operations BIBAFull-Text 284-288
  Robert S. Bolia; W. Todd Nelson; Scott H. Summers; Richard D. Arnold; Jennifer L. Atkinson; Robert M. Taylor; Robert Cottrell; Courtney L. Crooks
Proponents of network-centric warfare have espoused the notion that the continuing expansion of military networks will engender concomitant increases in the efficiency of collaborative military decision making. They suggest that network-centric information architectures will increase the ease with which decision quality information can be explicitly shared, and will also lead to self-synchronized action based on the shared situational model supported by the network. The paper takes a multidisciplinary look at the problem of collaborative decision making in military operations. The authors come primarily from research laboratory research and engineering backgrounds, but among them also number a professional air battle manager with significant experience in collaborative decision making in tactical and operational environments and a military psychologist required to deal with the training and selection issues posed by network-centric operations.

COGNITIVE ENGINEERING AND DECISION MAKING: Cognition and Perception in Displays

Assessment of Display Attributes for Displaying Meta-Information on Maps BIBAFull-Text 289-293
  Ann M. Bisantz; Jonathan Pfautz; Richard Stone; Emilie M. Roth; Gina Thomas-Meyers; Adam Fouse
In many domains, operators need to understand and act on large volumes of information from a variety of sources. Operators are particularly challenged by the need to reason about the qualifiers of that information. These qualifiers, or "meta-information", include characteristics such as the uncertainty associated with data, the age of the data, and the source of the data. Often, these critical data qualifiers are not presented, or are not incorporated into the primary information displays used by operators. In this research, we conducted a controlled experiment to investigate the utility of four common color display attributes (hue, saturation, brightness, and transparency) for displaying meta-information under different map background, task, and meta-information-type conditions. Results indicated that participants could rank and rate display elements which varied based on saturation, transparency and brightness similarly to expected ranks and ratings. Background effects were limited; but task type and framing effects indicated that the "natural" direction for ranking may be context-dependent.
Visualizing Uncertainty to Improve Operators' Spatial Proximity Judgments in Uncertain Surroundings BIBAFull-Text 294-298
  Andrew Brolese; Sam Huf
Graphic representations of uncertainty have been found to be a superior method of visualizing uncertainty in aviation and maritime operations. The primary aim of the present research was to examine the extent to which various uncertainty ellipse representations (50%, 75%, 95%, and 99%) affected decision making performance when participants were asked to judge the proximities of two or three targets to an own-ship position. The research comprised two separate studies, with 300 trials in each. Each trial required participants to utilize an uncertainty ellipse surrounding each of the targets in order to determine the closest target to the own-ship. Decision making performance was assessed via target decision accuracy analyses, reaction time analyses and the discrepancy between participants' associated probability estimate and the ground truth. The impact of feedback on the accuracy of participants' judgments was also examined in Study 2. The implications of the findings to naval systems, as well as directions for future research, are proposed.
Effect of Display Icon Modality on Situation Awareness BIBAFull-Text 299-303
  Laura D. Strater; Jennifer M. Riley; Laurie A. Faulkner; John R. Hyatt; Mica R. Endsley
The present study investigated the effectiveness of different icon modalities in supporting situation awareness (SA) when using a densely populated battlefield COP. The MilSTD 2525B symbology was compared to modified versions of this symbology that were either miniature or proportional, and the U.S. Army Research Lab's blobology concepts. ROTC cadets viewed a simulated military advance that displayed each of the four representation modalities with presentation order counterbalanced. At the end of each segment, cadets responded to a rapid battery of questions about their SA using the Situation Awareness Global Assessment Technique (SAGAT). Participants also evaluated the different icon modalities in terms of both user preferences and the icons' perceived utility in supporting SA. Although participants perceived the current MilSTD 2525B representations as easiest for assisting them in monitoring friendly and enemy forces, the objective SAGAT measure showed that SA performance was highest using the proportional icon modality. Results are discussed in the context of designing unit representations to effectively support SA.
Effects of Symmetry and Number of Compositional Elements on Interface and Design Aesthetics BIBAFull-Text 304-308
  Michael P. Bauerly; Yili Liu
This article describes two experiments investigating the effects of manipulating two compositional elements, symmetry and the number of compositional building blocks, on subjective appraisals of interface aesthetics. The two experiments use stimuli with identical composition but varying subject matter. The first experiment uses abstract black and white geometric images while the second uses realistic looking webpages as stimuli. Both experiments have three levels for each of the two independent variables, with the dependent measure being subjective ratings of aesthetic appeal. Results from both experiments show that the number of compositional elements influences aesthetic appeal ratings. For the abstract imagery, symmetry also plays a role such that subjects find the more symmetric images appealing. Implications of these findings on interface design and previous research are discussed.
Comparison of Audio Systems for Intelligibility in Multitalker Speech Displays BIBAFull-Text 309-313
  Mattias Kindstrom; Otto Carlander; Lars Eriksson
It can be advantageous for mobile applications of audio systems to be lightweight and small. An experiment investigated speech intelligibility for multiple talkers of a stereo presentation and two different 3D audio systems. The 3D audio systems consisted of a relatively small and lightweight Commercial-Off-The-Shelf (COTS) display and a professional hardware display considered bulky and heavy. Each of 12 participants listened to one to four call signs combined with two background voices, with the task to identify and localize the voice of each call sign. The results show that the COTS 3D audio as compared to stereo generated a larger amount of complete sets of identified call signs and a larger proportion of identified single call signs in a set. The professional display generated a larger proportion of identified single call signs in a set compared to stereo. These results suggest that 3D audio based on COTS components could be used for increasing intelligibility of radio calls in mobile applications demanding relatively small and lightweight equipment.

COGNITIVE ENGINEERING AND DECISION MAKING: Evaluating the Effectiveness of a Joint Cognitive System: Metrics, Techniques, and Frameworks

Evaluating the Effectiveness of a Joint Cognitive System: Metrics, Techniques, and Frameworks BIBAFull-Text 314-318
  Scott S. Potter; David D. Woods; Emilie M. Roth; Jennifer Fowlkes; Robert R. Hoffman
An implication of Cognitive Systems Engineering is that joint cognitive systems (JCS; also known as complex socio-technical systems) need to be evaluated for its effectiveness in performing the complex cognitive work requirements. This requires using measures that go well beyond "typical" performance metrics such as the number of subtask goals achieved per person per unit of time and the corresponding simple baseline comparisons or workload assessment metrics. This JCS perspective implies that the system must be designed and evaluated from the perspective of the shift in role of the human supervisor. This imposes new types of requirements on the human operator. Previous research in CSE and our own experience has lead us to identify a set of generic JCS support requirements that apply to cognitive work by any cognitive agent or any set of cognitive agents, including teams of people and machine agents. Metrics will have to reflect such phenomena as "teamwork" or "resilience" of a JCS. This places new burdens on evaluation techniques and frameworks, since metrics should be generated from a principled approach and based on fundamental principles of interest to the designers of the JCS. An implication of the JCS perspective is that complex and cognitive systems need to be evaluated for usability, usefulness, and understandability; each of which goes well beyond raw performance. However, conceptually-grounded evaluation frameworks, corresponding operational techniques, and corresponding measures for these are limited. Therefore, in order to advance the state of the field, we have gathered a set of researchers and practitioners to present recent evaluation work to stimulate discussion.

COGNITIVE ENGINEERING AND DECISION MAKING: Detecting Signals, Events, and Abnormal Situations

Impact of Sensor Noise Magnitude on Emergent Features of Ecological Interface Design BIBAFull-Text 319-323
  Olivier St-Cyr
This paper describes a study on the impact of sensor noise magnitude on the emergent features of an Ecological Interface Design (EID) interface using a representative thermal-hydraulic process simulation. Previous studies conducted by St-Cyr and Vicente (2004, 2005) showed no difference between EID and Single-Sensor Single-Indicator (SSSI) interfaces when the magnitude of sensor noise was globally increased to all sensors. However, to date, no study investigated the impact of gradually increasing sensor noise magnitude to selected sensors that are used to derive emergent features portrayed on EID interfaces. The current study filled part of this gap by locally increasing the magnitude of sensor noise. Results show that performance of EID group decreased, while performance of the SSSI group did not. However, the performance of EID participants was not inferior to that of SSSI participants. This is explained by the fact that participants in the EID condition had to deal with distorted emergent features.
Towards Deceptive Intention: Finding Trajectories and its Analysis BIBAFull-Text 324-328
  Jiun-Yin Jian; Toshihiko Matsuka; Jeffrey V. Nickerson
This study investigated how an individual's deceptive intention may be inferred from non-verbal behavioral representation while simultaneously concealing suspicious movement. Using a paper-and-pencil test, 33 participants were asked to deceive a hypothetical surveillance system. Results showed that deceptive intention can be inferred from trajectories drawn by participants. Patterns of trajectories were clustered. The majority of participants believed that not being suspicious is more important than being deceitful. Features exhibited in trajectories require more in-depth qualitative analyses in future studies. Computer-based experiments are also recommended.
Operating Multiple Semi-Autonomous Robots: Monitoring, Responding, Detecting BIBAFull-Text 329-333
  Roger A. Chadwick
The concept of one operator controlling multiple unmanned ground vehicle (UGV) robots is examined in a simulation of a multiple UGV search task. Semi-autonomous robotic UGVs were simulated searching for radioactive targets while operators performed various sub-tasks including monitoring status, responding to prompted target decision events, and detecting contextual errors. Participants executed a series of scenarios using 1, 2, or 4 UGVs simultaneously. The detection of contextual errors is particularly difficult when multiple vehicles are being supported. Specific interface features designed to assist with multiple vehicle operations are discussed including a quick video playback (QVP) function.
Effects of Sensitivity, Criterion Shifts, and Subjective Confidence on the Development of Automaticity in Airline Luggage Screening BIBAFull-Text 334-338
  Poornima Madhavan; Cleotilde Gonzalez
We examined the effect of cognitive factors on the development of automaticity in a complex task. Participants (n = 24) performed a luggage screening task where we manipulated stimulus mapping (consistent vs. varied), frame size (small vs. large), memory set size (1 vs. 4) and time constraint, and examined their effects on participants' sensitivities, criterion shifts and confidence. Results revealed that the highest cognitive advantage in terms of high sensitivities and minimal deviations from optimal beta was afforded by the combination of small memory sets and consistent mapping of targets, after extended practice. Varied mapping of stimuli under high memory loads exerted a negative effect on sensitivities and induced a greater shift from optimal beta. The concurrence of high memory loads with varied mapping also led to decreases in confidence that hindered automatic detection of targets. The results have implications for training individuals to develop appropriate decision-making strategies in complex vigilance tasks.
Performance Assessment of Humans in Leadframe Inspection: A Preliminary Study BIBAFull-Text 339-343
  Abhinesh Bhuvanesh; Mohammad T. Khasawneh
Defect detection and classification are important tasks for both product quality assurance and process improvement in the manufacturing industry. In leadframe manufacturing, samples of cut leadframes are taken immediately after stamping and examined by human inspectors. Early defect detection is critical for reducing waste of raw material and achieving a high quality product. In this paper, the performance of several participants was tested on the basis of inspection speed and accuracy. The tests were carried out using images of three leadframe designs with varying number/type of stamping defects. Response surface methodology was used to analyze the test results. In addition to designing better training systems, the results can be used by manufacturers to monitor their inspectors' performance. Due to the generic nature of the inspection task, the results can be further applied in other industries as well.

COGNITIVE ENGINEERING AND DECISION MAKING: Mediating Factors that Influence Cognition

An Examination of Situation Awareness and Confidence Within a Distributed Information Sharing Environment BIBAFull-Text 344-348
  Frederick M. J. Lichacz
In the present paper, the relationship between situation awareness (SA) and confidence was examined within a distributed information-sharing environment using both extant SA methodologies to study the relationship between SA and confidence and psychophysical methodologies (e.g., calibration and resolution) that examine the relationship between decision-making and confidence. The results of this study suggest that the use of calibration and resolution techniques offer a fruitful avenue for expanding our understanding of the relationship between SA and confidence and ultimately the relationship between SA and performance.
Peer-Mediated Leap to Efficiency: Cost-Benefit Analysis in the Selection of Efficient Strategies BIBAFull-Text 349-353
  Franklin P. Tamborello; S. Camille Peres; Michael D. Fleetwood
There is ample evidence that computer users often do not progress from novice to expert levels of performance, particularly when efficiency is included in the definition of performance. This paper describes a theoretical argument that one of the pieces missing in the understanding of this process is an accurate assessment of how people calculate a cost/benefit analysis (CBA) of learning and using new techniques and strategies. While there are many explanations for why people often do not use accurate methods of calculating this ratio, there is little discussion describing why some people do. We suggest that an important and predictable influence on whether an individual uses an accurate CBA is the observation of others using efficient techniques. We propose that with a more full understanding of the CBA calculation process, it will be possible to predict when users will and will not utilize a more efficient technique.
National Patterns of Teamwork During an Emergency Management Simulation BIBAFull-Text 354-357
  Ida Lindgren; Kip Smith
As a means to facilitate coordination of international relief teams during sudden onset disasters, the UN has formed a structure called the On Site Operations Coordination Center (OSOCC). The main objective of the OSOCC is to help local authorities re-establish control in the affected area. As with any command and control operation where people from different parts of the world are involved, multiculturalism can become an issue. Differences in values, norms and attitudes can create problems in communication, planning and execution of the operation. We use the C3Fire microworld and the Schwartz Value Survey as our main instruments to study cultural influences on command and control decision making in simulated OSOCC. The C3Fire microworld has been used extensively in empirical research on command and control. Results show that culturally-driven differences in planning and allocation of roles/responsibilities can pose potential barriers to efficient decision making in command and control.
Bennefits of Decision Support Tools for Users with Differing Levels of Domain Expertese BIBAFull-Text 358-362
  CarolineC. Hayes; RichardA. Anderson
When designing decision support systems (DSSs) to support complex cognitive problem solving tasks, it is important to understand what classes of users (domain novices, intermediates or experts) are likely to benefit from it, and conversely, what types of benefits can one expect a given class of users (such as domain novices or experts) will derive. Unfortunately, this is not yet well understood. In this paper we examine a specific class of DSSs which assist users by generating solution options. We compared the results of this class of DSS for four domains and found that they tend to increase novices' solution quality more than experts', and that increase may come at the cost of more total time required to produce solutions (although this is not always the case.) Additionally, in an animal nutrition domain, we found that both experts and novices (particularly experts) tended to insist on detrimentally modifying computer generated solutions even when those solutions started out with very high quality. Lastly we discuss possible explanations and implications for DSS design.

COGNITIVE ENGINEERING AND DECISION MAKING: Interruptions and Task Resumption

Spring Ahead or Fall Back Exploring the Nature of Resumption Errors BIBAFull-Text 363-367
  Melanie Diez LeGoullon
It has long been known that interruptions can be disruptive, but the details on where people resume an interrupted task have been largely overlooked by the literature. This paper describes an exploratory study to understand where people resume a task following an interruption. The findings suggest that people are significantly more likely to commit an error on the first step immediately following an interruption than on non-interrupted steps. Furthermore, people seem more likely to repeat a step than skip a step during these resumption errors. Finally, this trend toward repeating steps disappears in errors of non-interrupted steps.
Mitigating Disruptions: Can Resuming an Interrupted Task be Trained BIBAFull-Text 368-371
  David M. Cades; J. Gregory Trafton; Deborah A. Boehm-Davis
Research has shown that with practice people improve on most tasks. It has also been made clear that over time interruptions become less disruptive. It is unclear whether the reduction in interruption disruptiveness is due to a general practice effect or specific to the interruption/resumption process. In this experiment, participants performed three sessions of a task with one, two, or three of the sessions containing interruptions. We found that in addition to all participants showing primary task improvement, those with more exposure to interruptions also showed improvement in dealing with the interruptions. Specifically, participants with practice on only the primary task did not show improvement with the interruptions. These results suggest that the mitigations of the disruptions are directly related to people getting better at handling the interruptions.
Helpful or Harmful Examining the Effects of Interruptions on Task Performance BIBAFull-Text 372-375
  Raj M. Ratwani; J. Gregory Trafton; Christopher Myers
Most research on interruptions has shown that they can be disruptive by causing a longer time to complete the primary task and by causing more errors on the primary task. However, a limited amount of research has shown that interruptions can actually be beneficial to simple primary tasks, a benefit that has been explained by arousal. We sought to replicate the finding that simple tasks can benefit from interruptions and to examine the specific processes that are actually improving as a result of the interruptions. More specifically, reaction time data and eye movement data were collected to account for motor actions and perceptual processes. Results indicate that participants' immediate action following the interruption was disrupted. However, participants' other actions during the interruption trials were actually performed faster and with fewer errors as compared to the control. This speed-up is not attributed to faster motor responses, but actually to faster perceptual processing.
Supporting Interruption Management Through Informative Tactile and Peripheral Visual Cues BIBAFull-Text 376-380
  Shameem Hameed; Thomas Ferris; Swapnaa Jayaraman; Nadine Sarter
Operators in data-rich event-driven domains need to be supported in effectively allocating their limited attentional resources to cope with numerous competing task demands and frequent interruptions. One prerequisite for achieving this goal is to provide operators with information that allows them to make informed decisions about, and before, (re)orienting their attentional focus. This study examined the effectiveness of using informative peripheral visual and tactile cues for this purpose. 30 participants performed a continuous visual task. Occasionally, they were presented with a peripheral visual or tactile cue that indicated the need to perform a competing visual task. The location, frequency, and duration of the interruption cues reflected the type, importance, and likely duration, respectively, of the interrupting task. The findings from this study show that the informative cues were detected and interpreted reliably. Information about the importance (rather than duration) of the task was used by participants to decide whether to switch attention. Failure to switch attention was explained to some extent by the misinterpretation of the cues. The findings from this research can inform the design of more effective notification systems for a variety of complex event-driven domains, such as aviation, medicine, or military operations.

COGNITIVE ENGINEERING AND DECISION MAKING: Models of Complex Domains

Emergency Management Decision-Making During Severe Weather BIBAFull-Text 381-385
  Leigh A. Baumgart; Ellen J. Bass; Brenda Philips; Kevin Kloesel
The Collaborative Adaptive Sensing of the Atmosphere (CASA) project will provide its end users with new weather radar data with finer spatial and temporal resolution than existing WSR-88D data. It is not clear what impact this new information will have on emergency managers. This work introduces a descriptive decision-making model of emergency management during the four severe weather phases: Pre-Storm. Severe Weather Watch, Severe Weather Warning, and Severe Weather Event. The initial model describes EMs' use of information and their decisions made. Eleven emergency managers participated in three questionnaires and two part-task simulated weather scenarios based on archived weather data. This work then refines the Severe Weather Warning phase of the model by validating the entries and adding data concerning the role of the information and precursors to decisions made and actions taken. The scenarios also highlight problems that EMs have with interpreting velocity data and with integrating data from multiple radar sources. These results will impact CASA system visualization design and training.
A Sociotechnical Systems Analysis of the BSE Epidemic in the UK Through Case Study BIBAFull-Text 386-390
  Andrea Cassano-Piche; Kim J. Vicente; Greg A. Jamieson
In 1986, Bovine Spongiform Encephalopathy (BSE) was identified in the United Kingdom. Millions of BSE-infected cows and were slaughtered and over 150 people contracted variant-Creutzfeldt Jakob Disease (vCJD), an inevitably fatal human form of BSE. The purpose of this study was to test the ability of Rasmussen's (1997) risk management framework to explain how and why BSE (and later vCJD) entered the human and animal food supply from 1986 to 1996. This study represents the first test of the ability of Rasmussen's framework to explain how and why accidents occur in the food production domain. Using a case study methodology, this study investigates how well the evidence of the case study supports the framework's seven predictions of how and why accidents occur in complex socio-technical systems. All seven of the predictions were supported by the evidence.
Control Task Analysis for Applied Settings BIBAFull-Text 391-395
  Tab Lamoureux; Lisa Rehak; Jeff Bos; Bruce Chalmers
As part of ongoing research at DRDC Atlantic, Cognitive Work Analysis (CWA) is being used to design enhanced capabilities for naval command and control systems. Typically, the first two steps (work domain analysis (WDA) and control task analysis (CTA)) are conducted, followed by the identification of design seeds for the development of new system concepts. To date, there has been little guidance in the literature regarding how to perform both WDA and CTA, although many practitioners have performed WDA. Fewer have performed CTA, so the interested analyst has few examples to draw from, in particular for studies in industry. The work discussed in this paper involved the use of CTA to analyse scenario-based data in order to characterize expert performance in control tasks. By understanding expert performance according to a decision ladder (DL) model, it is possible to accurately support the required level of performance in complex, dynamic, open domains. This paper presents an overview of the work and includes some examples of the analyses.
Using Models to Explore Air Traffic Controller Workload BIBAFull-Text 396-400
  Lynne Martin; Thomas Kozon; Savita Verma; Sandra Lozito
When a new system, concept, or tool is proposed in the aviation domain, one concern is the impact that it will have on operator workload. As an experience, workload is difficult to measure in a way that will allow comparison of proposed systems with those already in existence. Chatterji and Sridhar (2001) suggested a method by which airspace parameters can be translated into workload ratings, using a neural network. This approach was employed, and modified to accept input from a non-real time airspace simulation model. The following sections describe the method and pilot test comparing a future airspace concept with a current day baseline in terms of workload levels. The results presented describe a preliminary analysis from using these models with the data from two non-real time model runs.
Comparison of the CF Doctrinal and Applied Operational Planning Process BIBAFull-Text 401-405
  Lora Bruyn Martin; Lisa Rehak; Tab Lamoureux; Bob Vokac; David Bryant
Several alternative models of operational planning have been proposed that adopt an intuitive or recognition-primed decision strategy, compared to one that is analytical. Although these models have been generated from anecdotal reports and observations of planning in operational settings, a systematic comparison of doctrinal and applied planning processes has never been documented. This paper describes the work done to empirically compare the planning process, as applied during a Brigade (Bde) level exercise, to the doctrinal Canadian Forces (CF) Operations Planning Process (OPP). Observers followed and documented all of the planning functions performed by the Plans Cell using the CFOPP as a reference. Results suggest that: the applied OPP, conducted at Brigade level, is a hybrid and abbreviated version of doctrinal OPP; planning is some what opportunistic and involves intuitive decision making by both the Commander and Staff; the OPP, as applied in an operational setting, is a command-driven process, and, intuitive decision making at individual (lower) function level by Staff member could lead to more efficient planning. These results have implications for doctrine, training, OPP process refinement and planning tool design.

COGNITIVE ENGINEERING AND DECISION MAKING: New Directions in the Control of Attention

The Implications of Crossmodal Links in Attention for the Design of Multimodal Interfaces: A Driving Simulation Study BIBAFull-Text 406-409
  Thomas Ferris; Robert Penfold; Shameem Hameed; Nadine Sarter
The design of multimodal interfaces rarely takes into consideration recent data suggesting the existence of considerable crossmodal spatial and temporal links in attention. This can be partly explained by the fact that crossmodal links have been studied almost exclusively in spartan laboratory settings with simple cues and tasks. As a result, it is not clear whether they scale to more complex settings. To examine this question, participants in this experiment drove a simulated military vehicle and were periodically presented with lateralized visual indications marking locations of roadside mines and safe areas of travel. Valid and invalid auditory and tactile cues preceded these indications at varying stimulus-onset asynchronies. The findings confirm that the location and timing of crossmodal cue combinations affect response time and accuracy in complex domains as well. In particular, presentation of crossmodal cues at SOAs below 500ms and tactile cuing resulted in lower accuracy and longer response times.
Neuro-Physiologically-Driven Adaptive Automation to Improve Decision Making Under Stress BIBAFull-Text 410-414
  Michael C. Dorneich; Patricia May Ververs; Stephen D. Whitlow; Santosh Mathan
The advent of netted communications and a wide array of battlefield sensors is enabling real-time information streaming and asset management. However, the burden of information management is placed solely on the receiver of the information. Honeywell Laboratories developed a Communications Scheduler (CoS), an adaptive information management system for the dismounted Soldier, driven by an assessment of the individual's current cognitive capacity to process incoming information, in order to improve decision making under high task load conditions. An evaluation was conducted to demonstrate whether cognitive capacity to perform under differing task loads could be detected using neuro-physiological sensors and then if the adaptive automation would appropriately regulate information flow. Results revealed an improvement in primary task performance, no degradation in concurrent secondary tasks, and lower subjective workload ratings while performing cognitively challenging working memory tasks with the CoS, although a slight loss in situation awareness of lower priority message was found. The appropriate allocation of cognitive resources is key to managing multiple tasks, focusing on the most important ones, and maintaining overall situation awareness.
Human Performance with Vocal Cueing of Automation State Changes in an Adaptive System BIBAFull-Text 415-419
  Heather L. Warren-Noell; David B. Kaber; Mohamed A. Sheik-Nainar
Previous research on cueing of control mode changes in adaptive systems has focused on the use of visual cues with some work on complex auditory cues. Research has not explored the use of vocal cues for automation state changes and human performance implications. This study investigated vocal cues as feedback on adaptive robotic system states for supporting operator performance when responding to control mode transitions compared with visual (icons) and auditory (earcons) feedback. Thirty-two participants performed a virtual reality simulation of a telerobot-assisted underwater mine disposal task. Modal cues were presented with task phase changes and robot control mode changes. Cue type and complexity (length of messages) were varied between and within subjects, respectively. Operator performance was evaluated in terms of time-to-task completion, workload, and situation awareness. Results demonstrated vocal cues to be superior to simple visual icons and no cueing for performance. Earcons did not produce worse performance ratings than vocal cues for complex messages. The results of this study are applicable to the design of future automated systems.
Effects of Expertise and Situation Complexity on Visual Attention and Action Planning for Air Traffic Control BIBAFull-Text 420-423
  Seok Hoon Hyun; Kyeong Tae Kim; Sun Mi Song; Jong Sung Yoon; Jae In Lee; Sun Min Cho; Young Woo Sohn
Analyses of eye tracking and think-aloud protocol data were performed to examine novice-expert differences in perceptual and cognitive aspects of air traffic controllers' situation awareness. In Experiment 1, three groups of field air traffic controllers (experts, intermediates, novices) were asked to perceive situations that were manipulated by complexity. In Experiment 2, protocol analysis of controllers' situation awareness was performed to extract cognitive strategies as a function of expertise. Then delayed-recall task and interviews on air traffic control plans for the recalled situations were also executed. Results showed that expert controllers concentrate only on several critical features and have their own strategies to reduce mental workloads.
Sentry Duty Performance Is Robust Under High Cognitive Load BIBAFull-Text 424-426
  G. E. Adam; D. Merullo
Cognitive demands are increasing in military tasks. A good deal of research has been conducted regarding vigilance performance of the dismounted Soldier. However, changing task demands and increased technological equipment are altering Soldiers' duties. It has become imperative to study performance under higher workload conditions, especially to understand Soldier responses in a multi-task situation. In this study, military volunteers responded to targets on a marksmanship simulator while also performing a secondary auditory task. Cognitive load on both tasks was varied. Sentry duty performance was more robust when the number of targets was high as compared to low. Secondary task latency, but not task completion was affected by workload on the primary task. Overall, performance was best when volunteers had the highest task demands. Explanations for these performance patterns will be explored.

COGNITIVE ENGINEERING AND DECISION MAKING: Cross-Cultural Interactions: Methods and Motivations for Study

Cross Cultural Interactions: Methods and Motivations for Study BIBAFull-Text 427-431
  Christopher A. Miller
Human factors practitioners have become increasingly aware of the need for attending to team interaction dynamics. This has produced substantial research, methodological advances and, ultimately, recommendations for team design, training, interaction support and assessment. Concurrently, awareness has grown that cross cultural differences influence the usability and safety of technologies. To date, however, human factors practitioners have rarely considered the intersection of these two topics: cross cultural interactions in team performance settings and/or the design and assessment of multi-cultural teams (and of technologies to support them). This panel will review the motivation for such research and a variety of approaches to conducting it. Central themes will be (a) definitions and dimensions of cultural differences, (b) team performance assessment methodologies appropriate and useful in cross-cultural team research, and (c) cross-cultural team design, training and aiding methodologies that are the targets of such research.

COGNITIVE ENGINEERING AND DECISION MAKING: Taking Cognitive Work Analysis One Step Further

Foundational Issues for Work Domain Analysis BIBAFull-Text 432-436
  Gavan Lintern
Lind (2003) has offered a critical analysis of Work Domain Analysis as executed in Cognitive Work Analysis. I review his critique and conclude that relatively few of his arguments have merit. Work Domain Analysis has a unique role to play within Cognitive Engineering. Although only some of the issues raised by Lind require resolution, consideration of those selected issues would be useful for the development of Cognitive Work Analysis.
Using Work Domain analysis to analyse perfusionists' conceptualisation processes during routine and failure cardio-pulmonary bypass scenarios: Preliminary outcomes using markov chain analysis BIBAFull-Text 437-441
  Anne Miller; Joe Power
Cardio-pulmonary bypass (CPB) involves the maintenance of whole body perfusion during cardiac surgery. While CPB is safe, emergencies do occur and perfusionists are expected to respond appropriately. However, perfusionists' training programs appear to be underdeveloped. In addition, there appears to be little understanding about how perfusionists conceptualise their work domain. This paper presents a work domain analysis-based (WDA) protocol for analysing perfusionists conceptualisations. A WDA of the CPB is presented. A hi-fidelity simulation environment with a video-cued recall interview data collection protocol is described and a Markov Chain analysis of verbal protocols is outlined using two participant data sets. We conclude that with further participant data analysis this novel approach offers promising insights into conceptualisation processes and exposes addition procedural, organisational and engineering issues that may need to be included in curriculum development.
Supporting the Strategies of Cardiac Nurse Coordinators Using Cognitive Work Analysis BIBAFull-Text 442-446
  Catherine M. Burns; Kathryn Momtahan; Yukari Enomoto
We conducted a cognitive work analysis to elicit the strategies of cardiac nurse coordinators (NCs). NCs field telephone calls from cardiology and cardiac surgery patients and make recommendations based on determinations of the severity of the patient's condition. We used a semi-structured interview technique to elicit various strategies. We then developed a decision making tool that deliberately supports these strategies. In this paper we discuss the elicitation of strategies and the transfer of these strategies into a design artifact.
An Examination of the Key Concepts of the Five Phases of Cognitive Work Analysis with Examples from a Familiar System BIBAFull-Text 447-451
  Neelam Naikar
Cognitive work analysis (CWA) is recognized, principally, for work domain analysis. Relatively little research has been directed at the remaining four phases of CWA and, as a result, the concepts of these phases of analysis are less well understood. This paper examines the concepts of all five phases of CWA with examples from a single 'system' - a home. A home is a highly familiar system that is characterized primarily by social or intentional constraints. The examples in this paper, therefore, complement the case study provided by Vicente (1999) of DURESS, a thermo-hydraulic microworld simulation that is defined largely by physical or causal constraints. In addition, this paper provides a starting point for examining several issues relating to the later phases of CWA, including whether or not they are useful or unique, their relationship to other approaches for work analysis, and methodological shortcomings.

COGNITIVE ENGINEERING AND DECISION MAKING: Cognition in Complex Domains

Cognitive Complexities Impacting Army Intelligence Analysis BIBAFull-Text 452-456
  Jonathan Pfautz; Ted Fichtl; Sean Guarino; Eric Carlson; Gerald Powell; Emilie Roth
The primary goal of this effort was to understand the problems faced by military intelligence analysis personnel as well as how, and to what degree, the identification of these problems could guide the development of computational support systems. To develop this understanding, we performed a literature review, knowledge elicitation interviews and a cognitive task analysis (CTA) in the domain of Army Intelligence Analysis at the Brigade Combat Team. This effort consisted of identifying: (1) the major functions or cognitive tasks entailed in Army Intelligence Analysis; and (2) the complexities in the domain that pose challenges to performance of these cognitive tasks. Identifying the cognitive tasks and the challenges faced in performing those tasks provided a basis for determining opportunities for more effective support of human information processing and decision-making. In this paper, we document selected results of this analysis effort.
Contextual Control Modes During an Airline Rescheduling Task BIBAFull-Text 457-461
  Karen Feigh; Amy Pritchett; Tina Denq; Julie Jacko
Tasks in complex, dynamic environments typically require many activities including information seeking, communicating, coordinating, judging, decision making, and implementing decisions. This paper examines how humans organize their actions, viewed as a form of control, by analyzing the selection of contextual control modes during an airline schedule adherence task. The experiment varied time limits and introduced a sudden change in the task during the last run. After each run, participants recorded their solution, NASA TLX workload ratings, and self-assessment of contextual control mode. Participants reported operating in, and transitioning between, different contextual control modes in response to time limits. Contextual control modes did not correlate with performance or TLX ratings of demand and effort but did correlate with time limit, TLX-frustration and TLX-performance ratings. The results suggest that high performance may be achieved through different contextual control modes and imply that decision aids should support multiple modes.
Assessing Safety Culture Issues Through Observations of Nuclear Power Plant Operators in Incident Management BIBAFull-Text 462-466
  Paulo V. R. Carvalho
The aim of this paper is discuss how the sociotechnical environment influences the behavior of nuclear power plant (NPP) control room operators. The interest of this research is to investigate how the operators' cognitive strategies are supported by the overall work system of the organization, such as the implementation of a safety culture enhance program. We based our research in field studies in a nuclear power plant control room. Activity analysis during the actual operator crew work was the basis of our research methodology. We use electronic media, such as audio and video recorders, and field notes in order do get empirical data. We identify problem areas in the organization work design system that brings constraints to these cognitive strategies, showing how these problems are related to the different organizational levels.
Multiple Vantage Points of the Common Operational Picture: Supporting International Teamwork BIBAFull-Text 467-471
  Michael D. McNeese; Mark S. Pfaff; Erik S. Connors; Joaquin F. Obieta; Ivanna S. Terrell; Marc A. Friedenberg
This paper summarizes multiple perspectives of the common operational picture (COP) in military and civilian crisis management domains viewed from three vantage points: historical, conceptual, and practical. The term COP extends prior research on large group displays to describe a visual representation of tactical, operational, and strategic information intended to generate situation awareness. We present four strata of interest to formulate an innovative conceptual framework of the COP based on user-team needs: structure, representation, processes, and management. This conceptual framework is applied as part of a review of recent and ongoing projects that examines current research gaps in the application of geographic information systems (GIS) to international humanitarian response.
Affective Factors: A Model of Cognition Under Emotional States BIBAFull-Text 472-476
  Moin Rahman
A range of aversive emotions, such as fear, anger and surprise, are automatically triggered when humans engage in mission critical tasks or operate in risky environments. These emotions modulate human cognition and behavior to protect and prevent from any harm being inflicted on them. Emotion accomplishes this by drawing attention to stimuli with emotional valence and by prioritizing the manner and order in which information processing occurs. It is known from research done in the neurosciences and social psychology that emotional states alter the cognitive processes non-consciously, well before the feelings of an emotion are perceived in the consciousness. Human information processing models, which inform and guide human factors research and practice, have not accounted for emotions. This paper presents a framework as to how emotions could be integrated into human information processing models. It does this by first demonstrating the primacy of emotional modulation of cognition, and its applicability to the field of human factors, particularly to the design of human-machine systems in mission critical domains.

COGNITIVE ENGINEERING AND DECISION MAKING: Teamwork

Information Distribution and Team Situational Awareness: An Experimental Study BIBAFull-Text 477-481
  Brian K. Sperling
Changes in task requirements and resulting system capabilities have led to the addition of crewmembers, information displays, and monitoring and coordination requirements in many domains. The overarching objective of this experimental study was to test whether providing task relevant information to individual team members in a time critical environment, while limiting their access to non-task relevant information, would change team interactions by improving team shared situational awareness and consequently, improve performance. The results of this experiment support this hypothesis and provide a new understanding of how the distribution of information among team members affects the development of shared expectations and information requirements, team and individual performance, and communications that has not been empirically documented elsewhere.
Enhancing Situational Awareness and Team Performance Using Network Centric Technologies BIBAFull-Text 482-486
  Elliot E. Entin; Paul Hiniker; Rebecca Grier; Tyrone Jefferson; Gary Vecchio; Jacquiline Harkins
A network-centric oriented technology that fused the User Defined Operational Picture (UDOP) and the Lightweight Collaborative Whiteboard (LCW) was compared to the baseline Global Command and Control System (GCCS). The UDOP environment allows the user to personally tailor the dynamic map and collaborate on the map via drawing, marking, and annotation that instantly appears on all other team member's maps. The GCCS map provides none of these capabilities. It was hypothesized that the UDOP environment will foster higher situational awareness and more adequate shared mental models than GCCS. Given that quality shared mental models and situational awareness have been associated with higher performance it was hypothesized that the UDOP environment would produce higher situational awareness and performance than the GCCS environment. Findings supported these hypotheses; higher situational awareness and performance were associated with the UDOP environment.
Changes in Team Composition After a Break: Building Adaptive Command-and-Control Teams BIBAFull-Text 487-491
  Jamie C. Gorman; Nancy J. Cooke; Harry K. Pedersen; Jennifer Winner; Dee Andrews; Polemnia G. Amazeen
An experiment exploring the effects of team composition on the acquisition and retention of team performance and cognitive skill is reported. Team performance was measured in the context of photographing ground targets in an unmanned aerial vehicle synthetic task environment. Team process was taken as a measure of team cognition. Experimental results include the findings that team mixing and longer retention intervals have a short lived deleterious effect on team performance immediately after the interval, while team mixing has a positive effect on team process after the interval. These findings suggest that changes in team composition and retention interval can lead to improvements in team cognition if a brief decrement in team performance post-interval can be afforded. These results are interpreted as perturbation of established coordination patterns due to team mixing leading to more flexible and adaptive teams. Implications for process-oriented research are also considered.
Team Communication With and Without Aids for Transmitting Remote Information BIBAFull-Text 492-496
  Laurel Allender; Patricia L. McDermott; Jason Luck; Alia Fisher
The introduction of unmanned vehicles (UVs) and real-time electronic information presentation to military teams is intended to keep Soldiers safe and enable more effective performance. Two game-based experiments were conducted in which teams conducted a time-limited "Black Hawk Down" rescue mission with and without UV-provided information. When UV information was available, it was relayed between team members in face-to-face communication or remotely, with or without electronic maps, and with or without video images from the UV. Three types of analyses were performed. The communication content of the verbal protocol was analyzed and the use of information display technologies and employment of strategies was tabulated. The verbal protocol analyses revealed the push/pull of team communication and common confusions. Results of the technology use and strategy assessment form the basis for recommendations for display design and recommended practice for the use of such technologies in the field.
Shared Perception of Risks in Emergency Situations between Pilots and Air Traffic Controllers BIBAFull-Text 497-500
  Su Ae Park; Young Woo Sohn; Kyeongtae Kim
Most of the aviation research on shared understanding have focused on coordination between cockpit crew. But coordination between pilots and air traffic controllers (ATCs) is critical for flight safety as well. This research determined whether pilots' perception of risk differs from ACTs' when they face the same flight situation. To assess the differences, we had pilots and ATCs evaluate the risk associated with emergency situations. Our risk rating data showed that there were differences in risk perception between pilots and ATCs. Factor analysis further suggested that pilots' risk perception was based on the immediacy of risk whereas ATCs' perception was based on the responsibility for controlling the emergency situation. This research has a practical implication for effective crew resource management (CRM) training.

COGNITIVE ENGINEERING AND DECISION MAKING: Functional Models of Work Domains

Cognitive Fieldwork in Emergency Crisis Management: Developing the I-T-P Abstraction Hierarchy BIBAFull-Text 501-505
  Arthur C. Jones; Michael D. McNeese
Through a work domain analysis, utilizing a mixed-methods approach, an understanding of the motivations and constraints of the emergency services domain was gathered. The domain analysis revealed a significant shortcoming of the currently-implemented systems when they are tasked to respond to atypical situations, such as mass-casualty incidents. The collected qualitative data was encoded into an abstraction hierarchy model which has been modified to represent the elemental components of an information system: information, technology, and people. The resulting I-T-P Abstraction Hierarchy model can be used to guide the design of information systems which have the capacity to scale between normal day-to-day operations, up to significantly more complex situations.
The Srk Inventory: A Tool for Structuring and Capturing a Worker Competencies Analysis BIBAFull-Text 506-509
  Ryan Kilgore; Olivier St-Cyr
Worker Competencies Analysis (WCA) is the fifth and final phase of the Cognitive Work Analysis (CWA) framework. Unlike the earlier four phases, there is a dearth of published work illustrating how WCA is conducted within the context of CWA. The lack of concrete examples of the application of WCA has both practical and pedagogical ramifications, making it difficult to perform and understand this phase of analysis. This paper attempts to address this gap. Following a review of the CWA framework, WCA is introduced with the Skill, Rules, and Knowledge (SRK) taxonomy. Then, a methodological tool for structuring and capturing the execution of WCA -- the SRK Inventory -- is presented. Finally, a practical application of the SRK Inventory to a TRACON microworld is discussed. This paper is intended to serve as a resource to future CWA practitioners and researchers, and to stimulate discussion of methods and tools for better supporting WCA activities.
Applied Work Domain Analysis: Translating Knowledge to Representation BIBAFull-Text 510-514
  Angela Li Sin Tan; Martin G. Helander
This paper describes a method for transforming knowledge elicited from real life applications into Rasmussen's Abstraction-Decomposition Space (ADS). The ADS is used to represent knowledge in a Work Domain Analysis (WDA), the first of five stages in a Cognitive Work Analysis. The WDA is highly conceptual and is mostly used by trained practitioners. There are many concepts and rules in the construction of the ADS. These make it difficult for practitioners to transform and map their data onto the two dimensional (2D) ADS. In Applied Work Domain Analysis (AWDA), we introduce a new dimension, cause-effect, thereby creating a 2D orthogonal space called the Motivation-Expectation Space (MES). The rules for constructing the MES are easier to apply than the ADS. After constructing the MES, practitioners can map information in MES onto the ADS.
Communication, Coordination, and Integration of Cognitive Work Analysis Outputs BIBAFull-Text 515-519
  Lisa A. Rehak; Tab M. Lamoureux; Jeff C. Bos
Cognitive Work Analysis is widely considered to offer a strong method for analysing domains that are not rigidly defined; where novel problem solving and unanticipated factors demand flexibility in operator performance. However, CWA is also thought to be unwieldy and time consuming. Recent work conducted on tight budgets has necessitated the development of methods to improve the coordination, integration and communication of work between CWA analysts. In particular, the use of Critical Decision Method for generating data, the use of exemplars for improving analysis validity and reliability, and the animation of outputs for communication purposes, have proven key in developing CWA-based design recommendations quickly and cost-effectively. This paper describes these efforts and provides some examples of the outputs.
Applied Comparison Between Hierarchical Goal Analysis and Mission, Function and Task Analysis BIBAFull-Text 520-524
  Renee Chow; Bob Kobierski; Curtis Coates; Jacquelyn Crebolder
This paper uses a case study approach to compare applications of Mission, Function and Task Analysis (MFTA) and Hierarchical Goal Analysis (HGA) to identify requirements for systems design in a military context. The two approaches were used to analyze three tactical positions in the Operations Room of a Halifax Class naval frigate. MFTA produced a four-level hierarchy; the bottom level of which specified tasks to be performed by the three naval operators. HGA produced a hierarchy that ranged from four to eight levels; every level specified goals, each assigned to an operator and each associated with a controlled variable. MFTA was found easier to apply, as job positions and time were used as frames of reference to identify tasks. HGA was found harder to apply, as goals were not defined by position, organizational structure, or time. MFTA successfully identified operator tasks, while HGA successfully identified both operator tasks and interactions that could benefit from technological support.

COGNITIVE ENGINEERING AND DECISION MAKING: Choosing Levels of Automation for Better UAV Control

Autonomy in Human-Robot Team Control BIBAFull-Text 525-529
  Jijun Wang; Michael Lewis
Human control of multiple robots has been characterized by the average demand of single robots on human attention or the distribution of demands from multiple robots. When robots are allowed to cooperate autonomously, however, demands on the operator should be reduced by the amount previously required to coordinate their actions. The present experiment compares control of small robot teams in which robots were controlled either independently or coordinated via Machinetta proxies. Coordinated robots found more victims and searched wider areas.
Flexible Authority Allocation in Unmanned Aerial Vehicles BIBAFull-Text 530-534
  Hilde T. A. van Ginkel; Michiel F. L. de Vries; Joris J. M. Koeners; Erik Theunissen
The Ground Control Station (GCS) is a critical element in the control of Unmanned Aerial Vehicles (UAVs). The information provided by the GCS influences the operator's Situational Awareness (SA). In order to explore the consequences of authority on operator SA and overall performance, this research investigated the desired authority of two operator support functions that perform conflict detection and resolution in the time-critical domain. In the experiment, the Level of Authority (LoA) of these two functions was varied. Results show that, independent of the LoA. in many cases, the operator was able to detect a possible conflict before the conflict prediction function became active. This indicated that the operator had sufficient level 3 SA (projection of current state into the future) to detect the need for a tactical action. However, results also show a significant amount of unnecessary operator interventions. Finally, the results show that in many situations the operator did not have enough level 3 SA to come up with a good solution for a possible conflict and performance would have been better without operator intervention.
Evaluation of Interface Types in an Adversarial Team Based Environment BIBAFull-Text 535-539
  Gregory J. Funke; Scott M. Galster; W. Todd Nelson; Allen W. Dukes
The present study addressed the effects of a flexible delegation-type control interface for unmanned vehicles (UVs) on performance in a team-oriented, dynamic, adversarial environment. Thirty-six people served as paid participants in this study. Teams of two participants competed against each other in a RoboFlag simulation based on 'capture-the-flag.' Participants controlled their UVs manually, through automated commands, or both (flexible control). Results of the experiment indicated that task performance and subjective workload were adversely affected in the automation-only condition, but no differences were detected between the manual and flexible conditions. Overall, results support previous research using RoboFlag. Performance in the automation condition was insufficient to meet task demands indicating the inappropriateness of UV control limited in this fashion. However, the lack of performance differences observed in this task between the flexible and manual interfaces calls into question when the flexible delegation-type interface may provide a performance benefit.
Effects of Robot Control Mode on Situation Awareness and Performance in a Navigation Task BIBAFull-Text 540-544
  Jennifer M. Riley; Laura D. Strater
Our ability to complete tasks in remote environments has improved with increased sophistication of robotic systems. The quality of remote task performance is driven by the quality of human interaction with robots which can be dependent upon the operator's ability to acquire situation awareness (SA) for task completion. There are, however, often critical limitations in development of SA, which are projected to have a magnified effect when operators must task and control multiple unmanned systems. In this study, we investigated the effects the mode of robot control on operator performance and ability to develop SA while navigating two robots through two mazes. Participants were randomly assigned to groups to control the robots in serial (one after another) or in parallel (at the same time) either manually or using two types of automation. The participants also viewed a systems interface to monitor the status of the robots. Results indicate that participants under serial control produced higher SA scores, though not significantly different from SA scores observed under parallel control modes. The best navigation performance was observed under parallel control with a high level of autonomy that followed a prescribed set of navigation rules. This control mode also resulted in the lowest workload scores. Participants were better able to correctly respond to SA queries for lower level, perceptual items in the robotics task as compared to higher level comprehension and projection items. Performance in the monitoring task was found to be significantly, positively correlated to participant SA.
Managing Multiple UAVs: Are We Asking the Right Questions BIBAFull-Text 545-549
  Scott M. Galster; Benjamin A. Knott; Rebecca D. Brown
The limiting factor in how many unmanned air vehicles (UAVs) a single operator may be able to simultaneously control successfully may be constrained by the workload experienced by that operator. Recently, the focus on the cause of the workload and performance variation primarily stemmed from the number of concurrent UAVs controlled by a single operator. The present experiment systematically investigated the number of UAVs controlled and the number of targets each UAV had to provide information on during its flight. Additionally, an automation aid was evaluated to determine if cueing facilitated performance. The results suggest that the tasks of each UAV are just as much or perhaps even more important to consider when evaluating the source of increased operator workload and performance differences. Further, the automation, as employed in this experiment was limited in providing a practical benefit to the operator.

COMMUNICATIONS: Collaboration and Technology-Mediated Communication

Advantages of Co-Location for Effective Human to Human Communication of Information Provided by an Unmanned Vehicle BIBAFull-Text 550-554
  Jason Luck; Patricia L. McDermott; Laurel Allender; Alia Fisher
Much of the research on unmanned-vehicles (UVs) focuses on technology or interface design. This study investigated how to best support effective communication between the UV operator and the Soldier in the field using UV-provided information to complete a mission. In a previous study investigating the impact of different team configurations and the utility of supporting communication technologies, our team found co-location of team members to be beneficial (McDermott et al., 2005). In this experiment we investigate what aspects of co-location are key to successful team performance: Is face-to-face communication vital compared to voice-only when team members are distributed? Is the ability of the UV operator to see what the Soldier performing the mission can see critical? We also seek additional insight to inconclusive results from the first study regarding the utility of image transmission and access to an electronic map displaying both the UV and Soldier locations.
Effects of Distributed Teamwork and Time Pressure on Collaborative Planning Quality BIBAFull-Text 555-559
  Rick van der Kleij; Peter C. Rasker; Jameela T. E. Lijkwan; Carsten K. W. de Dreu
Distributed teamwork is not without its difficulties. The detrimental aspects of geographical dispersion of team members on effective teamwork are often invoked to justify reluctance "to go virtual", despite the fact that for some tasks, and under some conditions, distributed environments may be as good as, or perhaps even better than, meeting face-to-face. To test this assertion we compared radio communication and a more sophisticated communication environment to colocated face-to-face meetings on a collaborative planning task. The planning task required 36 dyads, working under low or high time-pressure conditions, to combine information and to produce a written plan. Our results confirm the detrimental effects of time pressure on the quality of collaborative planning and support the notion that distributed teams can produce work that is as good as work produced in face-to-face meetings.
Military Situation Awareness: Facilitating Critical Event Detection in Chat BIBAFull-Text 560-564
  Jean M. Catanzaro; Matthew R. Risser; John W. Gwynne; Daniel I. Manes
Chat has become a primary means of communication for military command and control decision makers. One of the most important aspects of military chat use is the ability to detect critical events quickly and accurately, a task often complicated by the large number of chat messages received during actual operations. The primary goal of this research was to identify factors that enable chat watchstanders to more rapidly identify the critical information embedded in chat messages. These factors, which include message highlighting and chatroom layout, have the potential to enhance the effectiveness and efficiency of information processing in fast-paced, information-rich operational environments. In this study, message highlighting techniques enabled users to detect 92% of highlighted events, in comparison to 83% of events that were not highlighted. These findings indicate that highlighting chat messages confers significant performance advantages, especially in conjunction with associated factors, such as chatroom layout.
Size Matters: The role of Auditory and Visual Scale in the Identification of Unfamiliar Voices BIBAFull-Text 565-568
  Ryan Kilgore
Augmenting spatialized audio environments with visual depictions of voice locations has been shown to increase voice-identification performance. How the relative scale of mixed audio/visual interfaces affects this benefit, however, is not well understood. In this experiment, we compared the accuracy, response time, and confidence of 36 participants in a spatialized voice-identification task using three visual scale conditions viewed from a common distance: a 2-inch display, a 10-inch display, and 25.5-inch display. Each display was investigated using eight spatialized voices presented in two audio scale conditions: voices distributed across the entire interaural axis or across only the central half. Results showed significantly greater voice-identification accuracy for the larger audio scale and the two largest visual scales, and increased response time for the smallest visual scale. Confidence in task performance remained unchanged across conditions. These results indicate large-scale audio/visual interfaces may best capitalize upon the perceptual benefits of visually representing spatialized voice locations.
Effects of Background Noise on Communication in a Collaborative Team Environment BIBAFull-Text 569-573
  Adrienne J. Ephrem; Douglas S. Brungart; Julie A. Parisi
Many command and control operations involve complex collaborative tasks that cannot be successfully completed without effective team communication. However, the ability to communicate efficiently in these tasks is often compromised by environmental factors, such as the presence of ambient noise. In this study, we attempted to quantify the effect that ambient noise might have on the completion of team tasks in an airborne conference room, where there is a severe cost and weight penalty for the noise countermeasures used to achieve each additional decibel of attenuation. Rather than relying on current ambient noise standards, which are based solely on point-to-point word intelligibility, we chose to base our measurement on a collaborative team "communicability" task that required subjects to achieve a consensus on the ordering of four random faces in each of eight labeled columns. Completion time in the task was measured with and without visual line-of-sight in three levels of ambient noise (55dBA, 70dBA & 80dBA). The results show that completion time in the task increased systematically with the level of the noise, but that visual cues had no significant effect on performance. The results are discussed in terms of their impact on the interpretation of the current standard for ambient noise in communication environments, and in terms of their more general implications for the study of team communication.

COMMUNICATIONS: Communications Student Session

Dynamic Display of In-Vehicle Text Messages: The Impact of Varying Line Length and Scrolling Rate BIBAFull-Text 574-578
  Joshua D. Hoffman; John D. Lee; Daniel V. McGehee
This study examined the effect of varying dynamic display characteristics of in-vehicle text messages on visual sampling behavior. Sixteen participants navigated a simulated driving environment while reading text messages on an in-vehicle display. Each participant was exposed to four combinations of message segment length (short or long) and scrolling rate (slow or fast). Visual sampling was measured by the frequency and duration of glances to the display and the roadway, and comprehension of messages was measured by a series of post-drive questions. Results showed that varying segment length and scrolling rate affected the number of glances made to the display, but not their duration. Participants adjusted their reading rate to accommodate the rate at which messages scrolled, which protected reading comprehension but reduced the time spent viewing the roadway as the rate increased.
Leveraging Work Domain Analysis for a Wi-Fi Enabled Mobile Device BIBAFull-Text 579-583
  Carl F. Smith
The proliferation of wireless networks and wireless-enabled handheld devices has spurred the design of Wi-Fi enabled mobile devices that automatically detect and identify wireless signals. Recent designs have proposed the use of an "intelligent" interface that changes modes based on some variable specific to the user or the environment. Specifying a method of identification given the unpredictable nature of human work presents a design challenge that is not easily addressed by conventional scenario or task based methods. A Work Domain Analysis was used to inform the design constraints of a mobile device interface used to support the transition between wireless networks with different constraints, as well as unanticipated tasks.
Using Spatial Intercoms to Improve Speech Intelligibility for International Teams BIBAFull-Text 584-588
  Michela Terenzi; Nandini Iyer; Brian D. Simpson; Robert S. Bolia; Francesco Di Nocera
One of the most critical aspects of international teamwork activity is communications, most of which are in English, despite the fact that most of the team members in the world are non-native English speakers. Previous research has demonstrated that apparent spatial separation of communications can lead to substantial improvements in speech intelligibility and reductions in communications workload (Bolia & Nelson, 2003). This study investigated the benefits of sound spatialization on non-native English speakers, showing a significant improvement in recognition of the correct responses when speech was provided spatially. This result confirms and extends previous research on the usefulness of spatial audio technology in order to enhance speech intelligibility in multitalker communications environments.
Comparison of Speech Intelligibility Test Between Air Conduction and Bone Conduction Using the Callsign Acquisition Test BIBAFull-Text 589-593
  B. Osafo-Yeboah; X. Jiang; M. Gripper; L. Lyons
Communication in the battleground is very critical for the military. With U.S forces engaged in combat operations around the world in the war on terror, the need for effective and efficient communication systems has become more and more important. There are, in general, two types of communication: air conduction and bone conduction. Although air conduction is more commonly used in industry, bone conducted radio communication offers an attractive means for infantry to communicate in the battlefield because it allows radio communication to be transmitted and received without compromising the soldier's awareness of his or her surroundings. Bone conduction interfaces are also lightweight and less bulky and are therefore easy to integrate into military headgear. Based on the findings of previous study, condyle was chosen as the location for the bone vibrator placement. This research compares performance between bone conduction and air conduction using the military's Callsign Acquisition Test (CAT). Results from this study will help better design bone conduction devices for the military in the future.
Integrating Collaborative Awareness in Synchronous Distributed Groupware BIBAFull-Text 594-598
  Lim Tek Yong; Halimahtun M. Khalid; Alvin W. Yeo
This paper presents a model for integrating collaborative awareness in development of a synchronous distributed groupware, which was expected to enhance team collaboration in home modification tasks. The model, which is a synthesis of Situation Awareness and Activity theory, has three levels of collaborative awareness, comprising subject-collaborator member, object-outcome, spatial-temporal relationship, and mediation-projector components. These components were hypothesized to support remote collaborators in performing collaborative tasks effectively. We report the findings of the first-level perception that tested the importance of subject-collaborator member and object-outcome components in enhancing awareness. Our experiment revealed that both components were frequently acquired during collaboration. If only the subject-collaborator member component was available, subjects made several errors, and if only the object-outcome component was present, subjects could not achieve common ground, nor distribute the task easily, or share their customization errors. Therefore, a groupware that supported both subject-collaborator member and object-outcome component is preferred in collaborative task performance.

COMMUNICATIONS: Communications Potpourri

Personification of Voice User Interfaces: Impacts on User Performance BIBAFull-Text 599-603
  Benjamin A. Knott; Philip Kortum
This paper describes the results of an experiment in which the behaviors of callers to two different natural language prompts in a simple voice user interface were measured. Callers into a call center heard one of two natural language prompts. In one of the prompts, the interface identified itself to the caller by name ("Hi, I'm Bill") while the other prompt did not. Results show that this simple personification led to significantly better user performance in several areas. First, more callers interacted with the system if the interface identified itself by name. Second, callers provided more complete statements of what they needed to the system. Third, callers generated fewer vague statements that would have required the system to re-prompt them for more information. Finally, callers who heard the named-prompt uttered more words on average than those who heard the un-named prompt. Implications for voice user interface design are discussed.
Benefits Analysis of the National Traffic Management Log BIBAFull-Text 604-608
  Tanya Yuditsky; Bart Brickman
Traffic Management Specialists within the Air Traffic Control (ATC) system strategically manage the flow of air traffic to minimize delays and congestion due to system stressors such as heavy volume, weather, and equipment outages. ATC facilities are required to log all traffic management initiatives (TMIs), coordinate the implementation of some initiatives with the Air Traffic Control System Command Center, and communicate TMIs to Traffic Management Specialists at all affected facilities and to the controllers within their facility. The Federal Aviation Administration developed the National Traffic Management Log (NTML) to provide a single system for automated coordination, logging, and communication of TMIs. This paper describes the results of an empirical comparison of TMI processing with and without NTML in terms of time, potential for user error, and workload.
Radio Interoperability: There is More to it than Hardware BIBAFull-Text 609-613
  Ronald P. Timmons; Susan G. Hutchins
Following 9/11, many public safety officials reported communications issues between first responders, echoing concerns predating the September 11, 2001 terrorist attacks. With increased availability of grant funds for homeland security, radio interoperability has become a top priority. The rush to address emergency radio interoperability has caused agencies to select equipment without consideration given to the human aspects of communicating during a crisis and proper communication device ergonomics. This paper presents the results of a field study, providing insight into typical communications inefficiencies and opportunities to maximize limited resources via improved procedures and product design.
Communication and Coordination Problems in the Hydocarbon Processing Industry BIBAFull-Text 614-618
  Jason C. Laberge; Sinem C. Goknur
Effective communication and coordination is important in the hydrocarbon processing industry. This paper represents the first step in a larger study with the goal of improving communication and designing solutions (technology, training, work processes) to support effective coordination. We administered a survey to 11 sites to understand and characterize communication and coordination issues. Results showed that communication and coordination could be improved between planning and operations (console, field, head operators), communication between units, between maintenance (technicians, coordinators, supervisors) and operations and during shift handover. Specific constraints that hinder communication and coordination included weak leadership, poor control room design, closed communication culture, deficient work processes, and varied situation and work environment constraints. Potential solution areas include procedures, electronic logs, group displays, CRM and leadership training, and the use of video-mediated communication.
Expressing Intent A Matter of Being Clear BIBAFull-Text 619-623
  Jenny Lindoff; Jan Andersson; Per Wikberg; Mj. Joakim Marklund; Mj. Thomas Ohlsson
How should a leader express his/her wish, or intent, to avoid misinterpretation so the subordinates know what he/she wants them to do? Two experiments were conducted to investigate how intent, expressed in terms of effects or capabilities, is interpreted. A number of staffs produced products and answered questions about the interpretation of the intent. In the first experiment the results show that the staffs who receive intent expressed in terms of effects produce better products and have a better understanding of the intent than the staffs that get the intent expressed in terms of capabilities. In the second experiment the intent expressed in terms of effects was purposely written less clearly than the intent expressed in terms of capabilities. The results show no difference between the produced products and the staffs' understanding of the intent. This indicates that it is not just a matter of clarity.

COMPUTER SYSTEMS: Novel Usability Methods in Theory and Practice

Effectiveness of Various Automated Readability Measures for the Competitive Evaluation of User Documentation BIBAFull-Text 624-628
  James R. Lewis
I examined samples from a number of companies' user publications using several automated reading measures and a graphics/text ratio. The goal was to answer two questions: Were there reliable differences in writing style among the competitors? If so, were these differences related to their rank position in published surveys of user satisfaction with documentation? Of the measures included in the study, only the Cloudiness Count had any significant relationship to rank position in the surveys. A second evaluation, focused on the components of the Cloudiness Count, indicated that both of its components (passive voice and 'empty' words - a type of infrequent word) contributed equally to its effectiveness. This is consistent with psycholinguistic research that indicates that it is harder for people to extract the meaning from a passive sentence relative to its active counterpart, and that word frequency is the variable with the most influence on the speed of lexical access.
The Use of Partnered Usability Testing to Help to Identify Gaps in Online Work Flow BIBAFull-Text 629-633
  Dianne Davis; Gordon Tait; Cindy Bruce-Barrett
The Hospital for Sick Children developed a web based referral process to replace their current paper based referral system for the acceptance and management of referrals from community pediatricians and other health care professionals. Partnered usability testing, involving an external usability consultant and an internal project manager (i.e., a nurse at the hospital), familiar with the referral process as well as the prototype functionality was used to assess the prototype before completing the final development stage. The partnered usability sessions were a unique way to deal with the usability test of a very complex application that must accommodate multiple user groups as well as multiple and interlinked workflows. This approach was very successful in identifying ways in which the application did not capture some of the more fine grained details of work flow. The detection of some of the subtleties related to workflow would not have been possible without the participation of the internal project manager who was familiar with the minutia of the paper referral process in addition to the detailed functions of the prototype and its "missing" functionality. Details of the roles and steps involved in partnered usability testing are discussed as well as keys to successful implementation.
The Personas' New Clothes: Methodological and Practical Arguments Against a Popular Method BIBAFull-Text 634-636
  Christopher N. Chapman; Russell P. Milham
We examine the popular Personas method and consider claims that personas can reflect empirical data and serve as an information source for development teams. We argue that there are significant methodological and practical difficulties for personas. It is difficult to determine how many, if any, users are represented by a persona, and thus is difficult to know whether a persona is relevant for intended users. Personas cannot be adequately verified or falsified and therefore have no demonstrable validity. We believe personas are likely to lead to political conflicts and to undermine the ability for researchers to resolve questions with data. We suggest potential research to evaluate the Personas method more thoroughly. Until the methodological issues are resolved, it is best not to consider personas to be a means to communicate data.
Eye Tracking of Evaluators Viewing Usability Videos: Opacity and Experience Differences BIBAFull-Text 637-641
  Terence S. Andre; Hudson D. Graham; Jenny L. Coker; Margaret A. Schurig
Usability evaluation recording technology provides the usability practitioner with the capability to record audio, video of the user, and desktop screen activity in a "picture-in-picture" (PIP) format, allowing the evaluator to observe the interface screen and the human user simultaneously. This study is the second in a series of studies to examine how best to present usability evaluation video so that evaluators reliably find usability problems. The research objective of this study focused on the opacity of the PIP video that is often displayed along with the desktop screen capture. A total of 16 undergraduate evaluators were used, with 8 having no experience and 8 having 20 hours of experience from an advanced human-computer interaction course. In addition, 6 usability practitioners were used to compare to undergraduate experiences. Eye tracking was used to determine the attentional focus of evaluators. Results showed that opacity levels of the PIP video did not influence the number of usability problems found for all three groups. All evaluators did focus more on the higher opacity PIP video, but this did not appear to influence their evaluation.
20 Applications in 8 Weeks: Lessons from Large-Scale Checkpoint Usability Testing BIBAFull-Text 642-645
  Wendy Yee; Jessica Buttimer; Neha Pathak
In 2005, User Centric was asked by a large technology organization to test over 20 different prototype software applications in face-to-face usability testing during a single 8-week period. We share our experiences and strategies for addressing the logistical challenges so that other usability practitioners can learn about approaches that worked. Challenges included low-incidence recruitment, short window for test preparation, domain-specific applications, moderator fatigue, report creation overlapping with testing, and high-volume production of detailed reports. We provide specific recommendations for staging large-scale checkpoint usability tests and identify which approaches worked especially well in a second round of testing.
Designing Enjoyable Videogames: Do Heuristics Differentiate Bad from Good BIBAFull-Text 646-650
  Timothy V. Ballew; Keith S. Jones
How does one design a fun video game? One way to guide design is through the use of heuristics. Federoff (2002) compiled a list of design heuristics based on the gaming literature and interviews with game designers. However, these heuristics were not validated. The present study attempted to validate these heuristics by having participants play either a lowly or highly rated PC game. Participants were asked to provide a rating of overall enjoyment and then rate the applicability of each heuristic. Analysis of 133 participants' ratings of overall enjoyment indicated that non-gamers felt both games were equally enjoyable while moderate and heavy gamers found the highly rated game most enjoyable. Further analyses indicated that participants considered approximately 75% of the heuristics to be more applicable to the highly rated game than the lowly rated one. The implications for the design of new video game heuristics are discussed.

COMPUTER SYSTEMS: Visualization and Representation on Displays

Visualization of Multiple Robots During Team Activities BIBAFull-Text 651-655
  Curtis M. Humphrey; Stephen M. Gordon; Julie A. Adams
As robotic systems encompass larger numbers of individual robotic agents, interface design must provide better visual representations that account for factors affecting the human operator's situational awareness. This work investigates three robotic team visualizations via an evaluation with sixteen participants who either had used robots or had no experience with robots. The team visualizations varied in how much information was displayed: only individual robots, individual robots connected via a semitransparent team shape, or a solid team shape. The evaluation results revealed that the two visualizations utilizing a team shape were used more frequently than the visualization displaying only individual robots.
Icon Design on Small Screens: Effects of Miniaturization on Speed and Accuracy in Visual Search BIBAFull-Text 656-660
  Sabine Schroder; Martina Ziefle
The current study experimentally investigated benefits and limitations of miniaturized information design in small screen devices. Three crucial factors assumed to interact were examined: the size of icons and of displays and the density of information (set size). Using icons from real cell phones, 20 subjects were required to search for a specific icon within a set presented on a limited screen area. All three factors were systematically varied and explored by means of visual search efficiency (reaction times and error rates). Information access was found to be significantly affected by all factors. Interaction effects showed that search efficiency was considerably higher with increasing icon size and both decreasing display size and set size. Based on the results, recommendations for an optimized interface design for small screen devices are derived which are useful to meet a sensitive cut-off between all three factors under study.
Using Composite Scene Authentication (CSA) as a Graphical Alternative to Alphanumeric Password Systems BIBAFull-Text 661-664
  Korey Johnson; Steffen Werner
Current authentication strategies seek to increase security by requiring users to create more secure alphanumeric passwords, but the inverse relationship between alphanumeric password security and memorability prevents users from being able to create a password that is both secure and memorable. Graphical user authentication mechanisms have been explored as a means to maintain security while enhancing memorability of passcodes. Current approaches often use unrelated picture sets from which participants have to remember a subset, with mixed results. Proposed in this paper is an alternative approach of using a Composite Scene Authentication (CSA) mechanism to maximize memorability of graphical passcodes. In the current study, a composite image consisting of nine elements was compared to a nine character hexadecimal password. Participants were able to correctly recognize the CSA mechanism 80% of the time, but only able to recall the hexadecimal password 20% of the time.
Design of a Resource Allocation Planning System BIBAFull-Text 665-668
  Kelly O'Hargan; Stephanie Guerlain
This paper proposes a generic human-computer software user interface design, called the Resource Allocation Planning System (RAPS), designed to support a person making resource allocation decisions with or without automation support. Although there are many algorithms for automatically solving resource allocation problems, it is often the case that human judgment is also required. Also, while there are software user interfaces to support decision-making for specific resource allocation problems, most of them serve more as organizational charts than as decision-support systems, and most of them become increasingly difficult to use as the size of the resource allocation problem increases. This paper discusses the design and rationale for RAPS and gives several examples of how RAPS can be adapted to a specific resource allocation problems.
Network Intrusion Detection Cognitive Task Analysis: Textual and Visual Tool Usage and Recommendations BIBAFull-Text 669-673
  Ramona Su Thompson; Esa M. Rantanen; William Yurcik
A task analysis is conducted for the complex task of network security engineers, intrusion detection (ID) of computer networks. ID helps engineers protect network from harmful attacks and can be broken down into the following phases: pre-processing information, monitoring the network, analyzing attacks, and responding to attacks. Different cognitive loads are placed on the engineer at each phase. Engineers also need to integrate information from a variety of tools and resources, which adds additional cognitive workload. Visualization tools have been developed to alleviate these workloads but they have had limited success. To address this problem, we make two recommendations: (1) these tools should be designed for use across the phases of ID; this reduces the number of resources used therefore reducing the workload of integrating information across sources, and (2) visualization tools should allow concurrent use of textual tools and resources that provide detailed information and a powerful interface.

COMPUTER SYSTEMS: Tactile and Haptic Interfaces

Ergonomics of Tactile and Haptic Interactions BIBAFull-Text 674-675
  Jim Carter; Jan B. F. van Erp
The area of tactile and haptic interactions has produced a number of exemplar systems and an even greater number of research papers. The time has come to systematize the knowledge that has been gained in order to produce guidance. The Ergonomics of Tactile and Haptic Interactions symposium provides an analysis of some of the complexities of tactile/haptic interactions and provides a number of ergonomic insights on how they should be designed and evaluated. Papers in this symposium present a model for analyzing and designing the complexities of tactile/haptic interactions, a research-based understanding of and guidance on the many dimensions of tactile/haptic encoding, application-based guidance on designing and utilizing tactile/haptic interaction techniques, and insights on how international standards are providing a compendium of ergonomic guidance in designing and evaluating tactile/haptic interactions.
The Range of Tactile Haptic Interaction Techniques BIBAFull-Text 676-679
  Ian Andrew; David Fourney
Tactile/haptic interactions make use of a far wider set of interaction techniques than other forms of human-computer interaction including traditional direct manipulation of screen objects by pointing devices. This paper explores the relationships between interaction tasks within applications and the interaction devices used for those interactions, both current and future. The attributes of those devices, and their various combinations within a device, are also discussed. It introduces and discusses existing techniques, together with developments in research and guidance relating to various tactile/haptic interaction techniques.
Applying the Gothi Model of Tactile and Haptic Interactions BIBAFull-Text 680-684
  Keith Nesbitt; Jim Carter
This paper discusses the emerging area of tactile and haptic display and some of the breadth of applications of tactile/haptic interactions. While many research studies have provided ergonomic insights into the design of tactile/haptic interactions, the many dimensions and properties of these interactions make it especially difficult to combine the guidance from these individual studies. The GOTHI-05 workshop (Guidelines on Tactile and Haptic Interactions, October 2005) brought researchers together to develop a collection of ergonomic guidance and a framework (the GOTHI model of tactile and haptic interaction (Carter, van Erp, et. al., 2005)) for organizing this guidance. The inaugural meeting of ISO TC159/SC4/WG9 further refined this framework and adopted it as the basis for structuring its new series ISO standards on tactile and haptic interactions. The model itself will be elaborated in ISO 9241-910 Framework for Tactile and Haptic Interactions. The model has already proven useful in identifying and organizing specific guidelines in the first drafts of ISO 9241-920 Guidance on Tactile and Haptic Interaction.
   The paper discusses the various dimensions and properties of tactile/haptic interactions, identified in an expanded version of GOTHI model and identifies major considerations based on this model for use by developers (and potentially by evaluators) of interfaces that make use of tactile/haptic interactions ISO, 2006).
The Multi-Dimensional Nature of Encoding Tactile and Haptic Interactions: From Psychophysics to Design Guidelines BIBAFull-Text 685-688
  Jan B. F. van Erp
Designers are very well aware of the multi-dimensionality of visual stimuli and extensively use dimensions such as color, form and contrast to encode information. An analogous multi-dimensionality applies to haptic and tactile stimuli. Based on the fact that the human visual system only has two receptor types (cones and rods) while the sense of touch has closer to ten, one might argue that the design space is even larger for tactile and haptic interactions than for visual. The approach taken in this paper is to take the different sensory systems and their (perceptual) characteristics as a starting point. Bridging the gap between the neurophysiological and psychophysical data and the design guidelines can give this field a head start. For example, data on just noticeable differences of frequency, amplitude, force, and indentation can be an important driver in choosing the encoding dimension in the multidimensional haptic/tactile design space.
Existing and Future Guidance on Tactile and Haptic Interactions BIBAFull-Text 689-693
  David Fourney; Jim Carter
Tactile and haptic interaction is becoming increasingly important in both assistive technologies and special purpose computing environments. ISO 9241 Ergonomics of Human-System Interaction is intended to deal with all modalities of human-computer interactions. While some individual parts do include some general guidance that can apply to tactile and haptic interactions, there are no existing parts providing detailed guidance relating to the particulars of tactile and haptic interactions. This lack of standards leads to serious ergonomic difficulties for users of multiple, incompatible, or conflicting tactile/haptic devices/applications. However, considerable research exists that can be used as the basis for a set of tactile and haptic interaction guidelines.
   This paper provides an historical perspective of research and standardization efforts and moves towards providing an understanding of the goals of the emerging set of tactile and haptic interaction standards. It discusses how standards are developed and focuses on newly initiated efforts to create a set of parts within ISO 9241 to deal with tactile and haptic interactions. These parts will include Part 900 Introduction, Part 910 Framework, Part 920 Guidelines, Part 930 Multimodal combinations, Part 940 Evaluation methods, and Part 971 Interfaces to publicly available devices. The paper also explains how the reader can get involved in these standardization activities.

COMPUTER SYSTEMS: Usability Evaluations in Military Systems

Command and Control on the Move: Assessing the Impact of Input Device, Button Size, and Road Condition BIBAFull-Text 694-698
  Ryan S. Labio; Charles P. Rowan; Lawrence G. Shattuck
Digital command and control systems have contributed to the success of the U. S. military in combat in recent years. Force XXI Battle Command Brigade and Below (FBCB2) and Blue Force Tracker are examples of systems that have provided an advantage on the battlefield. However, interface design of these systems has not been optimal, especially when they are employed in high stress and mobile environments. The present study examined the effects of input device (touch screen or trackball), button size (small, medium, large), and road conditions (still, highway, off-road) on performance. The dependent variables were accuracy, reaction time, and motion sickness. The experimenters tested seven undergraduate freshmen from the U.S. Military Academy. The data show that a touch screen monitor with large button size is optimal for moving vehicles. These findings have important implications for the design of human-machine systems expected to operate on the move.
Assisting Interruption Recovery in Supervisory Control of Multiple Uavs BIBAFull-Text 699-703
  Stacey D. Scott; Stephane Mercier; M. L. Cummings; Enlie Wang
Performance degradation due to interruptions is a critical issue, particularly when people are supervising highly autonomous systems in time and safety critical environments. Previous research in the development of automated support to help supervisory control operators resume task activities after an interruption has had limited success. This paper describes two new interruption recovery approaches that attempt to mitigate the disadvantages of previous approaches. In particular, this paper describes the design and initial investigation of a prototype assistive interface developed to support interruption recovery for supervisory control of multiple unmanned aerial vehicles (UAVs). These two 'replay'-type interruption recovery approaches enable increased user-control of the event discovery process and provide event 'bookmarks' to highlight emergent system events. The findings from this initial study provide several recommendations for the future design of interruption assistance tools for human supervisory control tasks.
Usability Testing of Console Components: Trackball, Number Entry, and Gross Navigation BIBAFull-Text 704-708
  Katie Hall; Melissa Weaver; Nancy Burton
The purpose of this study was to evaluate several aspects of the Aircraft Carrier-Tactical Support Center (CV-TSC) console design. These variables were tested individually in order to isolate their effect and make recommendations for the overall console design. Six trackball devices, three number entry methods (keyboard number row, keyboard number pad, and separate number pad), and three methods of gross navigation (trackball only, touch screen, and navigation buttons) were evaluated. All tests involved simple tasks with timing and accuracy measures collected, as well as subjective feedback.
   The results of the study indicated that trackball 6 outperformed the others in most objective measures and was also the most preferred trackball. There were no conclusive performance results for the number entry test; however participants indicated a preference for a number pad, either separate or integrated with the keyboard. The touch screen method of gross navigation was the best performer, although participants preferred the trackball-only condition.
Usability in Battle Management System Human-Machine Interface Design: Assessing Compliance with Design Guide Heuristics BIBAFull-Text 709-713
  Scott H. Summers
In 2005, the United States Air Force Air Combat Command and Air Force Research Laboratory released a Battle Management and Command & Control system human-machine interface Design Guide. A study was conducted at a North American Aerospace Defense Command air defense sector to assess a new command and control system for level of compliance with this new guide. Sixty-seven qualified command and control personnel participated in the pilot study, consisting of 15 qualitative survey items. Results indicate that the use of such a qualitative measurement instrument may prove effective in determining relative levels of compliance with usability guidelines.
Supporting the Expert and Novice in a Single User Interface BIBAFull-Text 714-717
  Scott Bachmann; David E. Kancler; Christopher Curtis
The Aircraft Maintenance and Intuitive Troubleshooting (AMIT) project is sponsored by the United States Air Force Research Lab's Human Effectiveness Directorate Logistics Readiness Branch (AFRL/HEAL) to investigate how to create a software tool to improve flight line maintenance troubleshooting. The AMIT project is a three year project that can be loosely divided into three stages: 1) research - determining expertise and defining the constraints of the task; 2) design - turning the findings into a tool; and 3) test - placing the tool in a constrained field test to assess its impact on performance in a naturalistic setting. This paper focuses on the recently completed design stage, as a case study.

COMPUTER SYSTEMS: Voice and Speech Systems: Usability and Performance

The Effects of Use on Acceptance and Trust in Voice Authentication Technology BIBAFull-Text 718-722
  Carl W. Turner; Jennifer A. Safar; Karthik Ramaswamy
A study was conducted to determine the effects of repeated usage on consumers' acceptance of voice authentication technology. Nineteen participants registered a voiceprint and then authenticated using their voice before completing five typical banking tasks using a functional speech-enabled Interactive Voice Response (IVR) system. Participants answered questionnaires regarding their attitudes toward voice authentication and biometrics at three points: (1) prior to using the system, (2) after registration, and (3) following completion of all banking tasks. Participants' preferences for voice authentication over user IDs and passwords increased pre-test to post-test. Multiple regression analysis revealed that their willingness to use the speech system was predicted by their trust in the system and by the quality of the system's voice. A second multiple regression analysis showed that satisfaction with the quality of the information provided by the system predicted participants' trust in the system. This paper discusses the importance of system trust in evaluating voice authentication technology.
Web-Based Comparison of Two Styles of Auditory Presentation: All TTS Versus Rapidly Mixed TTS and Recordings BIBAFull-Text 723-727
  James R. Lewis; Patrick M. Commarford; Cheryl Kotan
A current controversy in the interactive voice response (IVR) community is whether and under which conditions designers should use recorded audio when portions of the interface must be generated by text-to-speech (TTS). The purpose of this study was to examine user preferences for a very extreme case -- a prompt that incorporates multiple units of dynamic information in a single sentence. Two groups of IBM employees listened to and compared two auditory styles of information presentation (all information given by a single TTS voice and alternating recorded audio and the TTS voice.) The groups listened to both presentation styles in counterbalanced order and then indicated their preference and degree of preference. The percentage of respondents indicating a preference for the all TTS style was significantly greater than the percentage indicating a preference for the mixture of recorded and TTS.
Investigation of Confirmation Strategies for Speech Recognition Applications BIBAFull-Text 728-732
  Cheryl Kotan; James R. Lewis
Guidelines for speech user interfaces generally promote the use of delayed confirmation in speech recognition applications that require users to provide multiple elements of information. In our initial investigation of a simple delayed confirmation method, we discovered a significant design flaw (requiring users to review a fairly large amount of correct input multiple times when asked to correct two errors). To avoid this flaw, we designed two new methods. In one (Serial Collection/Correction), users named an item that needed correction, then made that correction before naming the next item to change. In the other (Batch Collection/Correction), users named all items that needed correction first, then changed the named items in sequence. An experiment comparing the methods indicated no significant difference in user preference, but significantly fewer memory errors occurred when using the Serial Collection/Correction method. Thus, we recommend the use of the Serial Collection/Correction method. We also recommend including an option to replay the information if a user has remembered the need to change an additional item, but does not remember which item to change.
A New Approach to Evaluating the Intelligibility and Naturalness of Shadowed Speech BIBAFull-Text 733-736
  Wallace J. Sadowski
Verbal shadowing refers to a task whereby a person, while listening to a continuous message, repeats the message aloud word for word. Some research suggested that shadowed speech is distorted and unnatural, while others have reported shadowed speech as clearly intelligible and containing prosodic contour. This research used a different approach to investigate the naturalness and intelligibility of shadowed speech. Another goal of this research was to determine whether shadowed speech is sufficiently similar to read speech, regarding intelligibility and naturalness, such that it might be acceptable for training speech recognition systems. This paper focuses on the subjective evaluation of shadowed and read speech to quantifiably measure the perceived differences. The results indicated that humans can detect statistically significant differences between read and shadowed speech; however, the magnitude of the differences may not be sufficient to deter its use for training speech recognition systems.
Exploring Verbal Shadowing as an Effective Method of Enrolling in a Speech Recognition System BIBAFull-Text 737-741
  Wallace J. Sadowski
The purpose of this research was to investigate the effectiveness of using verbal shadowing as a method of enrolling in a speech recognition system. Verbal shadowing refers to a task whereby a person, while listening to a continuous message, repeats the message aloud word for word. Typically the enrollment process involves users reading an enrollment script aloud and the system processes the speech output to create a personalized acoustic model which increases recognition accuracy. Exploring the feasibility of a non-visually based enrollment technique addresses important human factors issues - accessibility by users with visual impairments or educational limitations. This study found that read enrollments reduced mean recognition errors by 24.70% and shadowed enrollments reduced recognition errors by a mean of 24.64% - a difference of only 0.06%. While this was statistically significantly different, for all practical purposes, shadowing as a method of enrollment proved to be as effective as reading.

COMPUTER SYSTEMS: Input Methods and Interfaces

Psychomotor Performance of Input Device Users and Optimized Cursor Control BIBAFull-Text 742-746
  Christine Sutter; Martina Ziefle
This study examined the fit of the stochastic optimized submovement model (= SOS model; Meyer, Abrams, Kornblum, Wright and Smith, 1988) for cursor movements of two laptop input devices. 10 experienced users of touchpad (easy sensorimotor transformation) and 10 experts for the trackpoint (difficult sensorimotor transformation) executed clicking tasks. Given a model fit, the aim of the study was to discuss the well-known performance inferiority of input devices with difficult sensorimotor transformations on the basis of the SOS model. Cursor movements of both, touchpad and trackpoint, showed a basic fit with the SOS model. With the touchpad, the cursor was easier to control, resulting in a good performance: fewer submovements were carried out from the start to the target, and cursor velocity and acceleration were comparably low. Contrary, with the trackpoint cursor control was more difficult, accompanied by more submovements and a high inaccurateness in the target area: thus, even for experts, the difficult sensorimotor transformation of the trackpoint interfered with a proper motor execution. Actual and potential applications of this research include an optimization of cursor control for input devices and guidelines for their users.
Text Entry on a Virtual Keyboard: Evaluating Shape and Experience Effects BIBAFull-Text 747-751
  Marita A. O'Brien; Wendy A. Rogers; Arthur D. Fisk
This research study examined the design of a virtual keyboard that can be used for text entry with a rotary controller, particularly for users who may differ in age and experience with a particular system. Features of a virtual keyboard that have been shown to affect the individual movement and visual search components of the text entry task were assessed for younger and older adult users. Participants entered words by finding and selecting individual letters with a rotary controller on a keyboard arranged alphabetically or following the standard QWERTY keyboard. Performance was examined across different levels of experience with the task. We found that experience independently interacted with shape, arrangement, and age group. Both age groups improved their entry time overall and at each measurement period, but older adults learned more slowly. Although performance improved for both arrangements, the Alphabetic arrangement was significantly faster. Neither shape was significantly faster, but results suggest that the more salient corner features on the Plus facilitated memorization and retention.
Brain Machine Interfaces: Technology Status, Applications and the Way to the Future BIBAFull-Text 752-756
  Jan B. F. van Erp; M. Duistermaat; I. H. C. H. M. Philippens; H. A. H. C. van Veen; P. J. Werkhoven
Brain Machine Interfaces (BMIs) enable direct communication between the brain or nervous system and a machine without involving the sensory-motor system. BMIs are an embryonic technology and remarkable accomplishments have recently been reported. BMIs have a high potential and possibly an enormous impact on society, and may evoke a revolution in the way we interact with computers.
   If we look at the Human Factors and Ergonomics community's position in the BMI field, we do not have a meaningful track record yet. However, the thesis of this paper is that we as a community are in a good position to (1) facilitate a broadening of the focus of BMIs from therapeutic applications to general use and (2) to realise a spin-in of BMI technology to domains such as Human Computer Interaction, supporting people with special needs, and training and simulation.
Testing the Usefulness of a Pan-Tilt-Zoom (PTZ) Camera in Human-Robot Interactions BIBAFull-Text 757-761
  Curtis W. Nielsen; Michael A. Goodrich
Mobile robots can be used in situations and environments that are dull, dirty, or dangerous, allowing the operator to interact with the environment from a safe and convenient distance. To improve the usefulness of these robots, pan-tilt-zoom (PTZ) cameras are often used. This paper presents a user-study comparing the usefulness of robots with stationary and PTZ cameras in a search task utilizing both a traditional interface and an augmented-virtuality 3D interface. The results from the experiments suggest that with the traditional interface the PTZ camera and stationary camera have similar performance whereas with the 3D interface the PTZ camera improves performance.
The Interdisciplinary Perspective of Humane Intelligence: A Revisitation, Twenty Years Hence BIBAFull-Text 762-766
  Michael D. McNeese
Our current research involving intelligent interfaces for crisis managers, intelligence analysts, and police operations can be traced to a seminal position first published twenty years ago entitled Humane Intelligence. This perspective captures an adaptive systems philosophy through a wholistic blending of human and artificial intelligence designed to function within information surrounds. The original paper was foundational for prescribing how human factors might influence artificial intelligence, specifically within the domain of fighter pilots performing tactical operations. This paper revisits this theoretical approach to intelligent systems by reviewing principles, attributes, and ideas using a contemporary lens of human factors and ergonomics culture. After reviewing basic-level concepts the paper presents examples of how humane intelligence has both evolved and influenced several lines of research including concept mapping ontologies, fuzzy cognitive models, affective computing, scaled world technology, and human-agent architectures.

EDUCATION: Human Systems Integration (HSI) Education and Training

Human Systems Integration (HSI) Education and Training: It's Not Just Human Factors on Steroids BIBAFull-Text 767-770
  Lawrence G. Shattuck; Michael Drillings; Jacqueline Foxx; Robert Lindberg; Nita Lewis Miller
This panel builds on the work of a Human Systems Integration (HSI) panel convened at the 49th Annual Meeting of the Human Factors and Ergonomics Society. The present panel brings together leaders of the HSI community from the U.S. Air Force, the U.S. Army, and the U.S. Navy. These experts discuss the challenges in educating and training HSI practitioners. Among the HSI education and training challenges are developing student expertise in numerous HSI stove-pipe domains while equipping students with the tools, processes, and skills requisite for reconciling conflicts among the domains.

EDUCATION: Teaching HF/E Issues to Varying Audiences

Almost 50 Years of the University of Michigan Human Factors Engineering Summer Conference BIBAFull-Text 771-773
  Richard W. Pew; Paul A. Green
In 1957 Paul Fitts and Daniel Howland offered a human factors summer course at Ohio State University. Fitts moved to Michigan in 1958, and the next year he offered essentially the same course in Ann Arbor. The course has been given every summer since then. An estimated 3500 students from a diverse set of industries and countries have completed one or two weeks of the course. The list of lecturers includes many of the leaders who have shaped the field of Human Factors Engineering (HFE), and the course has gradually morphed from focusing on operators working with traditional hardware systems first to users of interactive computer systems and now to complex systems that incorporate computers and people ubiquitously. This paper will trace this history and comment on a few of the inevitable anecdotes that go with 50 years of experience.
Challenges and Lessons Learned in Teaching a Graduate Human Factors Course on a Compressed Schedule BIBAFull-Text 774-778
  Joseph Sharit
There is a current tendency for industrial engineering departments to augment their Masters Degree programs with programs targeted for off-campus students who are employed full time. These programs are motivated primarily by the revenue that they can potentially generate for academic departments. In this paper we discuss one such program in which each course is compressed into three consecutive weekends, and discuss the challenges of teaching these students a course on human factors engineering under these curriculum design constraints. Examples of lessons learned in teaching this course are summarized and possible interventions in course design are discussed, with the understanding that teaching such a course affords the opportunity for achieving buy-in to the human factors and ergonomics discipline within these students' respective organizations.
Curriculum Innovation Using Job Design Theory BIBAFull-Text 779-783
  Katherine Sanders; Patrick V. Farrell; Sarah K. A. Pfatteicher
"Introduction to Engineering" was designed in 1994 by a cross-disciplinary group of seven engineering faculty at the University of Wisconsin-Madison. The faculty group had recently completed a nine-month team-based professional development program, where they studied, discussed, and reflected upon the learning process. The group was asked by the administration to design a course to improve the retention of freshmen engineering students, with specific emphasis on the retention of underrepresented student groups. This paper highlights the human factors and job design foundations of this course in two ways. First, in that the course itself was created using theories of work motivation taken from classic literature and applied to the "work" of learning. Second, by creating a course that ultimately would be considered service-learning, students and faculty from diverse engineering departments would need and become familiar with human factors in design.
Recommendations for Teaching Team Behavior to Human FactorsErgonomics Students BIBAFull-Text 784-788
  Nancy J. Stone; William F. Moroney; Tracey B. Wortham
Many Human Factors/Ergonomics specialists are members of work teams. To prepare students for teamwork, the students' education should include team building exercises and experiences. During both the 2004 and 2005 HFES meetings panel sessions were held on teaching team behavior to human factors/ergonomics students. The first panel identified general approaches and areas requiring study, whereas the second panel focused on how to form and develop effective teams and how to collect and use peer ratings. This document integrates the information obtained from these panels, teaching resources, and audience input. Teaching outcomes, various forms used to effectively teach with teams, and additional references are provided. These complete recommendations are posted at: http://etg.hfes.org.
Are Students Learning About Human Factors and Ergonomics in Introductory Psychology Textbooks BIBAFull-Text 789-793
  Karen R. Young; Jeffrey J. Smith; Michael S. Wogalter; Christopher B. Mayhorn; J. Graham Baucom
An ongoing issue of the membership of the Human Factors and Ergonomics Society concerns efforts to educate audiences about human factors and ergonomics (HF/E). One important group to consider is students taking a beginning or introductory psychology course. The initial course in psychology usually reviews the scope of psychology and is taken by large numbers of individuals. In the present research, introductory psychology textbooks (n=123) published between 1969 and 2006 were consulted to identify the nature and extent of the coverage of HF/E. A clear increase in coverage was evidenced beginning in 1995. Although HF/E is now being mentioned significantly more often in newer texts, it is frequently limited in both amount and scope. The potential growth of graduate HF/E programs may be affected by the extent to which potential applicants are exposed to the discipline. Implications for HF/E are discussed and opportunities for increasing student exposure are identified.

EDUCATION: Accreditation/Recognition of Undergraduate HF/E Programs

Developing Criteria for Recognizing Excellence in Undergraduate Human Factors Education BIBAFull-Text 794-798
  Lawrence G. Shattuck; Ann M. Bisantz; Richard D. Gilson; William F. Moroney; Esa Rantanen
The purpose of this panel is report on the work of the Undergraduate Program Recognition Committee and to encourage discussion among attendees on the proposed criteria developed by the committee. The paper and the panel discussion will provide an overview of the graduate program accreditation process, report on the work of the Special Task Force on Undergraduate Program, and propose criteria that can be used to recognize the various types of human factors programs that currently exist.

ENVIRONMENTAL DESIGN: Office Ergonomic Intervention Panel & 3D Body Scan Method, Measure of Exterior View Lectures

An Easy, Effective and Useful Measure of Exterior View: Toward a User-Centered Perspective for Assessing Occupancy Quality BIBAFull-Text 799-803
  Jay L. Brand
An objective measure for external view -- percent optional exterior view -- was developed in a field study of two quite different office environments within the corporate headquarters of a large, manufacturing firm in the Midwest. As predicted, this measure correlated more highly with two subjective measures of environmental quality than objective, ambient light levels (ambient, task & daylight combined -- measured photometrically in lux) or objective daylight levels; also as expected, neither percent exterior view nor daylight levels predicted job performance/productivity. Contrary to predictions, this measure did not correlate with subjective measures of job satisfaction, morale, job quality, or organizational quality.
A 3D Body Scan Method to Measure Postural Deformations in Flexible Material Chair Backs BIBAFull-Text 804-808
  Anshu Agarwal; Alan Hedge
A 3D whole-body laser scanning method was used to evaluate the deformations of flexible material chair backs. Twenty-four Ss of different gender and body sizes sat in each of two ergonomic chairs (B, G). 3D images were analyzed for volumetric deformations. The chair back was divided into an upper region (from the lumbar through the thoracic to the shoulders), and a lower region (the lumbar/lower back area). When Ss sat with their back leaning against the chair back the upper region deformation was comparable for chair G (984.9 cm3) and for chair B (952.1 cm3). The lower region deformation, however, was significantly greater (p = 0.000) for chair G (393.3 cm3) compared to chair B (268.7 cm3). There were no significant differences in ratings of chair comfort.
Office Ergonomics Intervention Study Panel BIBAFull-Text 809-813
  Benjamin C. Amick; Michelle Robertson; Lianna Bazzani; Kelly DeRango; Anne Moore
Ergonomic issues in the office environment affect both workplace health and productivity outcomes. Currently the office ergonomics intervention literature is underrepresented in research studies with rigorous study designs and analytical methods. Furthermore, there exist no published replication intervention studies. Panel members are part of a multidisciplinary inter-institutional research group that conducted the same office ergonomics intervention study at two different worksites (one public and one private sector). Office workers agreeing to participate were assigned to one of two interventions - a highly adjustable chair coupled with an office ergonomics training (chair-with-training group) or the office ergonomics training alone (training-only group) - or a control group receiving the training at the end. During this discussion panel the effects of the interventions on ergonomics knowledge and computing behaviors, biomechanical changes, individual components of musculoskeletal and visual symptoms and productivity will be presented.

ENVIRONMENTAL DESIGN: Revisiting Sitting Cross-Cultural Aspects of Seating

Revisiting Sitting Cross-Cultural Aspects of Seating BIBAFull-Text 814-821
  Kageyu Noro; Rani Lueder; Shunji Yamada; Goroh Fujimaki; Hideki Oyama; Yuki Hashidate
This chairperson's paper summarizes the background and objectives of a panel session on cross-cultural postures. The panel session will present research findings that exemplify the implications of regional and cultural assumptions and perspectives on seating comfort and design.

ENVIRONMENTAL DESIGN: Diagnosing Environments: Environmental and Medical Human Factors

Identifying Systemic Factors that Impact Performance in the Cardiac Surgery Operating Room BIBAFull-Text 822-824
  Douglas A. Wiegmann; Andrew W. ElBardissi; Joseph A. Dearani; Thoralf M. Sundt
Errors with serious consequences continue to occur at a high rate in many surgical specialties. In this study, the Human Factors Analysis and Classification System (Wiegmann & Shappell, 2003) was used to develop a structured interviewing tool for prospectively assessing the systemic factors that may predispose operating room (OR) personnel to making errors. Approximately 50% (n = 68) of all staff involved in patient care within the cardiac surgery OR at our institution participated, with an equal proportion represented across staff specialties (Surgeons, Anesthesiologists, Nurses, Perfusionists and Technicians). Results identified a variety of potential error-producing factors present in the OR setting. While such factors were viewed by OR staff as occurring infrequently, significant relationships between the estimated frequency of systemic problems and specific error forms were identified. These findings can inform both the development of theoretical models of surgical error, as well as the practice of developing targeted intervention programs.
Incomplete Recuperation of WMSDs after an Office Ergonomic Intervention BIBAFull-Text 825-829
  Mariah K. Levitt; Alan Hedge
Survey data on the effects of an office ergonomic intervention (negative-tilt keyboard tray, upper mouse platform, chair, and training) were analyzed. Baseline and one-year post-intervention data on work activities, individual factors and the frequency and severity of upper body work-related musculoskeletal disorders (WMSDs) were compared. Results showed that post-intervention the sample prevalence of any upper body symptoms decreased from 73% to 47.3% and the upper body symptom mean severity score decreased by 30.7%. There was an 8% reduction in the frequency of symptoms for each body region for symptomatic workers. The ergonomic intervention resulted in significant improvements in comfort and in WMSDs, but for many workers MSD symptoms persisted above background levels, suggesting that other factors may be affecting symptom etiology.
Using a Wheelchair Seating System to Measure Postural Effects on User Comfort and Typing Performance BIBAFull-Text 830-833
  Scott Haynes; R. L. Grubbs; Sarah Endicott; Karen Williams; Mike Williams
Many people who experience chronic low back pain find that sitting upright for long periods of time can cause discomfort. For some, a measure of relief is achieved by lying down periodically throughout the work day. Devices exist that allow computer operators to work from a significantly reclined or supine posture. However, very little has been written to describe the impact of these alternate postures on typing performance and user comfort. The ability to move from an upright to a supine posture is also important for the health of many wheelchair users. Tilt and recline wheelchair seating systems are frequently used to address this need. This study used a modified tilt and recline wheelchair seating system to measure the impact of five different postures on typing performance and user comfort. Preliminary analyses indicate discomfort in upper extremities may cause significant differences in typing speed and user comfort in supine positions.
Combining Checklists and Staff Surveys - A Powerfull Tool to Evaluate Operating Rooms BIBAFull-Text 834-837
  S. Koneczuy; U. Matem
Awkward postures, potential hazards and the adaptation to sub-optimal conditions belong to the normal course of life within operating rooms (ORs) and OR units. Ergonomic deficiencies of the OR are mostly the reason therefore. Medical technical devices were found to be lacking in usability due to such as unclear symbols, impracticability, hindrances and insufficient ease in handling. The positioning of devices in the OR shows ergonomic problems that in most cases necessitates an unavoidable awkward working posture for the employees that causes pain. Potential hazards exist for the patient as well as for the OR staff. To detect those conditions a checklist for the OR was developed and evaluated in German hospitals. To confirm the objective results of the checklist, additional surveys were performed among the OR staff to gain subjective personal impressions. Combining the checklist's and the surveys' results is a powerful tool to evaluate the entire OR unit.
Health Information Maps: Combining Macroergonomics Concepts with Facilities Layout Tools BIBAFull-Text 838-842
  Teresa Zayas-Cabán
Health care consumers are faced with managing an increasing volume of health information and information technology solutions have been developed to support these activities. In order to develop appropriate solutions, it is important to understand the context in which lay persons manage their health information. This study was conducted to develop Health Information Maps, a facilities layout method that uses macroergonomics as a guiding framework. This article presents results from the first cycle of the study, which tested the feasibility of using the Maps methodology. Study results show that participants appeared to be engaged in the interview process and understand interview questions. Based on participants' responses, study methods have been expanded to add an explicit evaluation of the methodology by study participants. The interview has also been revised to account for differences between 'health insurance cards' and 'health insurance policy,' in order to focus solely on health insurance cards.

FORENSICS PROFESSIONAL: Issues In Forensic Human Factors

When Open and Obvious is Neither: The Importance of Context in Human Factors Forensics BIBAFull-Text 843-846
  Marc L. Resnick
This paper evaluates from a human factors perspective the legal theory that if a hazard is open and obvious, an injured party has limited legal recourse to pursue damages against the party that produced the hazard. A detailed human factors analysis of the context surrounding user behavior can call into question whether a hazard that may seem open and obvious to a layperson really is. A case study in which a judge considered dismissing a lawsuit because the hazard seemed open and obvious is used to illustrate how human factors testimony can significantly change the outcome of a trial. The human factors expert identified nine contextual elements that increased the likelihood that the plaintiff would be injured by the hazard despite its apparent obviousness. This testimony overcame the initial inclination of the judge and allowed the case to continue to trial.
Curb Ramps: Cross Slope Conspicuity and the Prevention of Air Steps BIBAFull-Text 847-850
  Kenneth Nemire
An observational study of pedestrian use of curb ramps was undertaken following the air step, fall and severe injury of a woman who stepped from the flared side of a curb ramp after mistaking it for the curb ramp itself. Her error apparently stemmed from using the red-painted curbs flanking the curb ramp as navigation cues for safe passage. The study found that paintingthe flared sides of the curb ramp red, to match the flanking curb and to contrast with the curb ramp, resulted in more people using the curb ramp, rather than stepping off the flared side of the curb ramp. Implications for painting curb ramps and for modifying existing regulations and standards arediscussed.
Who's in the Back Seat A Study of Driver Inattention BIBAFull-Text 851-854
  Steven R. Arndt; Christine T. Wood; Peter B. Delahunt; David Krauss; Carolyn T. Wall
Objects that are readily detectable and visible are not always noticed. Demonstrating the difficulty of detecting objects in a scene to people who are already expecting to see them and are aware of the objects' presence poses a challenge. In the following study, two conspicuous objects were placed in the back seat of a sport utility vehicle (SUV). The study parameters were selected in an attempt to replicate a situation involved in a criminal investigation, to test the hypothesis that drivers routinely check the back seat of the car before driving away, and to determine the likelihood of drivers noticing what would seem to be a salient set of objects in the rear seat. Two child-sized mannequins were placed in a prone position on the back seat of a large SUV. Naive subjects were asked to get in and drive the SUV 1.6 miles around a closed track at night. Twenty-seven out of 30 participants failed to notice the mannequins in the vehicle. Visual performance limitations, environmental expectations and "inattentional blindness" effects can account for the results and are discussed in this paper.
Who Really Knows About Reclining the Passenger Seat BIBAFull-Text 855-859
  S. David Leonard
Warnings are important for several reasons. They provide information about hazards to those who may be unaware of them. They may also serve as reminders about hazards in circumstances where the hazard may be forgotten, and they present information about how to avoid the hazards warned against. Some hazards are deemed open and obvious because they are presumed to be either known to all who might encounter them or people are presumed to recognize their risks by their characteristics. The present research considers a hazard (reclining the automobile passenger seat) that might seem to be obvious. One report indicated this might be the case. However, more recent research has shown it is not the case. This research examines the fact that different procedures produce different estimates of how well understood the hazard is. The conclusion is that it is important to consider experimental techniques in evaluating results.
People Do Not Identify Tire Aging as a Safety Hazard BIBAFull-Text 860-864
  Jennifer A. Cowley; Soyun Kim; Michael S. Wogalter
Tires are among the most critical components of motor vehicles, requiring proper maintenance to minimize the risks of accidents associated with failure. The failures at high speeds hi vehicles such as SUVs have resulted hi vehicle rollovers, serious injuries and occupant death. Tire degradation, as a result of age-related factors, can be contributor to tire failure for which many people may have little awareness. A total of 225 participants (101 non-student adults and 124 college students) were asked to list all contributors that they believed could cause the problems. Although most respondents mentioned one or more causes of tire failure, only 4.0% of the participants mentioned tire aging as a cause. These results suggest that a substantial proportion of the population is not aware of tire aging as a potential hazard. Implications for a multi-method labeling and warning system are described.

GENERAL SESSION: President's Forum

Human Factors and Ergonomic Science in the Courts: Expert Testimony in the Dispute Resolution Process BIBAFull-Text 865-869
  Robert V. Redding; Wendy A. Rogers; Arthur D. Fisk
The science of human factors and ergonomics (HF/E) contributes to the dispute resolution process in many ways. HF/E analysis can provide insights into product liability issues, vehicular accidents, industrial accidents, and more. The field is increasingly being recognized by lawyers as a means to help jurors and judges understand why events may have occurred; for example, why someone would use a product or drive a vehicle in a seemingly unsafe manner. Often, probable causes relate to design-induced or system-induced error. To understand the litigation influence of HF/E, we analyzed cases involving HF/E experts. Our findings revealed that: (1) HF/E science is well recognized in the judicial system; (2) competent HF/E experts are viewed as contributing to litigated matters; (3) individuals without HF/E training and experience will not be recognized as HF/E experts; and (4) admissibility demands that the intellectual rigor used for court must be consistent with other discipline-related work.

GENERAL SESSION: Human-Robot Factors: Robots in the Workplace

Human-Robot Factors: Robots in the Workplace BIBAFull-Text 870-874
  Jenny Burke; Michael Coovert; Robin Murphy; Jennifer Riley; Erika Rogers
As we celebrate the 50th anniversary of HFES, this panel discussion presents the emerging field of human-robot interaction as a critical research area in human factors for the next 50 years. Robots in the workplace are poised to change our lives over the next 50 years much as computers have the past 5 decades. This panel gathers four experts with diverse experience in studying technology's effects upon work to discuss the implications of robotic technology for work environments. Topics include the cognitive, social and affective human characteristics that impact human-robot interaction, the potential impact of robotic technology in the workplace, and factors influencing acceptance of robots at work. The implications for design of robotic products and systems are also discussed.

GENERAL SESSION: Human Factors Applications in Complex Domains

Canine Models of Occupational Expertise BIBAFull-Text 875-879
  William S. Helton
The role of inherent talents or biological predispositions in the acquisition of expertise is controversial. Because the genetics and early life experiences of humans are not open to direct manipulation, human experimental studies are of limited utility in resolving this issue. Studies employing non-humans as expert models may prove more useful. In order for non-humans to be considered proper models of human experts, there needs to be evidence supporting a shared expertise-acquisition mechanism. A candidate mechanism is deliberate practice. The deliberate practice theory of expertise acquisition was investigated in dogs competing in agility. The relationships between amounts of accumulated deliberate practice and agility performance measures were examined in this study, controlling for sex, breed, age, and height. There was a statistically significant relationship between the amount of deliberate practice and measured performance in agility dogs.
Newell and Simon's Logic Theorist: Historical Background and Impact on Cognitive Modeling BIBAFull-Text 880-884
  Leo Gugerty
Fifty years ago, Newell and Simon (1956) invented a "thinking machine" called the Logic Theorist. The Logic Theorist was a computer program that could prove theorems in symbolic logic from Whitehead and Russell's Principia Mathematica. This was perhaps the first working program that simulated some aspects of peoples' ability to solve complex problems. The Logic Theorist and other cognitive simulations developed by Newell and Simon in the late 1950s had a large impact on the newly developing field of information-processing (or cognitive) psychology. Many of the novel ideas about mental representation and problem solving instantiated in the Logic Theorist are still a central part of the theory of cognitive psychology, and are still used in modeling the complex tasks studied in human factors psychology. This paper presents some of the theoretical precursors of the Logic Theorist, describes the principles and implementation of the program, and discusses its immediate and long-term impacts.
Making Faces: Exploring Perceptions of Personality Based on Emotional Expressions BIBAFull-Text 885-888
  Brian E. Tidball; Sasanka Prabhala; Jennie J. Gallimore
Researchers at Wright State University have been working on modeling computer agents with personality. Perception of personality between humans is based on many factors, one of which includes facial expression. Many researchers have explored the ability to recognize emotion in faces, while other research focuses on perception of personality based on faces (physiognomy). The purpose of this study combines these two areas of research to determine how participant's rate different personality dimensions based on emotional expression. Participants rated ten static computer faces on the 30 personality subtraits from the Big Five Factor model of personality. The results show that participants did rate personalities differently depending on the facial expression. Participants perceived similar personality traits between the two different faces that expressed the same emotion. Results will be discussed along with future research directions.
Instant expertise for novice responders performing cardiopulmonary resuscitation (CPR) BIBAFull-Text 889-893
  Paul M. Picciano; Frank A. Drews
More than 300,000 people die from sudden cardiac arrest (SCA) annually in the United States. As professional responders such as EMTs make efforts to expedite their arrival, critical minutes pass jeopardizing the victim's health. Providing life-sustaining intervention in the first few minutes greatly contributes to healthier outcomes. Often, there are witnesses to SCA events that could respond immediately, but they are incapable of providing treatment. The just-in-time support (JITS) approach aims to assist novice operators in completing unpracticed tasks such as cardiopulmonary resuscitation (CPR) at the moment of need. By providing naive users plans, cues, and feedback, JITS systems facilitate goal accomplishment. The results of this work suggest a JITS device could empower novice responders with CPR capabilities. Widespread deployment of such a device could greatly decrease response time and save lives.
Real Video Clips Make a Real Difference: Video-Based Training for Improving Sterile Practices BIBAFull-Text 894-898
  F. Jacob Seagll; Yan Xiao; Grant V. Bochicchio; James Guzzo; Richard P. Dutton; Amy Sisley; Manjari Joshi; Harold C. Standiford; Joan Hebden; Colin F. Mackenzie; Thomas Scalea
Central venous catheter (CVC) -related infections are a significant souire of preventable morbidity and mortality. To reduce CVC-related infections, we developed a web-based educational intervention. Video records of care provider performance of CVC insertion were used in task analysis and in expert review of performance as part of a needs analysis. Stakeholder opinions of compliance to recommended sterile practices were elicited. Based on these data, we developed an online training course for residents on recommended sterile practices during CVC insertion. The course contained short video clips from actual patient care demonstrating common breaks in recommended sterile practices. We propose reasons why the video-based course was effective in promoting compliant behavior, and reasons training influences attitudes toward sterile practices.

GENERAL SESSION: Integrative Approaches to Understanding Complex Aspects of Human Performance

Vision Science for Visual Technology BIBAFull-Text 899-903
  Andrew B. Watson
As our primary means of gathering information from the world about us, vision has always occupied a central place in human factors. Beginning in the early 1980's, the Vision Group at NASA Ames Research Center sought to move visual human factors from its primarily empirical foundations to a new, model based formulation. The intent was to do this through development of computational models of visual performance. These would be more general than ad hoc empirical measurements, would be amenable to refinement over time, and would serve as the basis for computational human factors engineering tools. Since then the Vision Group has made some important contributions to fundamental vision science, and has also begun to fulfill the program envisioned at its outset.
Nasa-Task Load Index (Nasa-TLX); 20 Years Later BIBAFull-Text 904-908
  Sandra G. Hart
NASA-TLX is a multi-dimensional scale designed to obtain workload estimates from one or more operators while they are performing a task or immediately afterwards. The years of research that preceded subscale selection and the weighted averaging approach resulted in a tool that has proven to be reasonably easy to use and reliably sensitive to experimentally important manipulations over the past 20 years. Its use has spread far beyond its original application (aviation), focus (crew complement), and language (English). This survey of 550 studies in which NASA-TLX was used or reviewed was undertaken to provide a resource for a new generation of users. The goal was to summarize the environments in which it has been applied, the types of activities the raters performed, other variables that were measured that did (or did not) covary, methodological issues, and lessons learned.
Concurrent Task Management and Prospective Memory: Pilot Error as a Model for the Vulnerability of Experts BIBAFull-Text 909-913
  Key Dismukes
In five of the 27 major U.S. airline accidents between 1987 and 2001 in which the NTSB found crew error to be a causal factor, inadvertent omission of a normal procedural step played a pivotal role. Such omissions are a form of prospective memory error. My research group is attempting to link real-world prospective memory phenomena with task demands and with underlying cognitive processes. I briefly summarize studies from three quite different but complementary approaches: ethnographic studies, analyses of accident and incident reports, and laboratory studies. Five types of situation presented prospective memory challenges: episodic tasks, habitual tasks, atypical actions substituted for habitual actions, interrupted tasks, and interleaving tasks/monitoring. An experimental study found that inadequate encoding, inadequate cueing, and competing demands for attention make individuals vulnerable to forgetting to resume interrupted tasks.

GENERAL SESSION: Learning from Investigation: Reviewing the First Year of MEDCAS

Learning from Investigation: Experience with Understanding Healthcare Adverse Events BIBAFull-Text 914-917
  Christopher P. Nemeth; Richard I. Cook; Yoel Donchin; Meghan Dierks; Emily Patterson; Yuval Bitan; Jay Crowley; Stephanie McNee; Tina Powell
Thorough, objective investigation of medical adverse events rarely happens due to the complexity of the environment, litigation, risk, and socio-political implications. Special concerns can, and do, undermine investigation depth, breadth, and quality. Healthcare's distinct difference from other high hazard sectors requires a unique approach to adverse event investigation. We report on the initial results of a 15-month pilot program now underway to model a national healthcare investigation team. An example of adverse event investigation and organizational response illustrates these issues.

HEALTH CARE: Understanding and Facilitating Collaboration in Health Care

Understanding and Facilitating Collaboration in Healthcare BIBAFull-Text 918
  Cynthia Dominguez; Yan Xiao
Research of collaborative work in healthcare provides new insights into team performance, communication, coordination, and the role of information technology. These new insights may be translated into other domains where continuous operations by multi-disciplinary teams are essential. The symposium will provide a forum for a conceptual framework on shared information spaces (conversational and visual), the relational infrastructure and specific benefits inherent in effective collaboration across teams, interdisciplinary communication strategies in ICU settings, barriers to attaining common ground as well as strategies for facilitating common ground, and the nature of handoffs when pediatric ICU patients transfer to a step-down unit. All of these reports originated from empirical examinations of collaborative work in high stakes healthcare settings. As a whole, this symposium represents a snapshot of how human factors can contribute to healthcare by improving our understanding of how collaboration occurs and can be promoted in healthcare settings.
Multidiscplinary Perspectives on Collaborative Care BIBAFull-Text 919-923
  Jeffrey Brown; Cynthia Dominguez; Gerry Stahl; Lorri Zipperer
The development of high functioning healthcare teams is advanced through facilitative leadership, the development of socialization strategies that embrace the importance of tacit as well as explicit knowledge, and relational environments that promote transparency and trust. This report is a summary of reflections on collaborative practice from an interdisciplinary analysis of collaborative practice by a team of medical and social scientists. These reflections follow, and augment, a previous report on this study, and are based on multi-site research that included field visits, simulation, observation, and interviews.
A Distributed Cognition Approach to Understanding Information Transfer in Mission Critical Domains BIBAFull-Text 924-928
  Ayse P. Gurses; Yan Xiao; Paul Gorman; Brian Hazlehurst; Grant Bochicchio; Vinay Vaidya; Peter Hu
We developed a conceptual framework that describes how information transfer occurs in mission critical domains using a distributed cognition approach. According to this framework, information tools and the physical workspace comprise an "information arena", which plays a crucial role in information transfer. Information tools and the information arena support joint work and may improve efficiency and reliability by providing visual cues to collaborators, by getting everyone on the same page, by helping collaborators focus on critical information, by facilitating attention management under time pressure, and by providing an evanescent (transient) communication space. We illustrate the concepts in this framework using an example from multidisciplinary rounds, an information transfer mechanism common in the intensive care unit, a mission critical domain. The framework can be used as a guide to further understanding of information transfer in mission critical domains and to develop information tools that facilitate and enhance discourse.
Structured Interdisciplinary Communication Strategies in Four ICUS: An Observational Study BIBAFull-Text 929-933
  Emily S. Patterson; Timothy Hofer; Suzanne Brungs; Sanjay Saint; Marta L. Render
Paired direct observations of a physician and nurse caring for 11 challenging patients at four Intensive Care Units (ICUs) were conducted to identify structured interdisciplinary communication strategies. Providers employed the following strategies at all four ICUs: 1) nurses listening to bedside (but not closed) rounds, 2) nurses cross-checking physician plans, and 3) physicians and nurses providing "heads-up" alerts. Providers employed the following at some of the ICUs: 1) nurses and physicians speaking privately following rounds (3/4 ICUs), and 2) nurses speaking during bedside rounds (2/4 ICUs). None (0/4 ICUs) conducted pre-round interdisciplinary briefings. None (0/4 ICUs) used artifacts explicitly designed to aid interdisciplinary communication (e.g., Morning Briefing Tools), although shared electronic and paper resources were used by both nursing and physician personnel. Implications of the findings are discussed.
Barriers and Facilitators of Common Ground in Critical Care Teams BIBAFull-Text 934-938
  Anna McHugh; Beth Crandall; Tom Miller
Effective collaboration among multi-disciplinary clinical team members has been recognized as a critical component of safe and high quality patient care. There are a variety of systems and procedures in place; however that can impede collaboration by impairing the team's ability to develop and maintain common ground. The current study was an exploratory effort that included an investigation of collaboration in the critical care environment. Direct observations in two urban Intensive Care Units and Cognitive Task Analysis (CTA) interviews with members of the critical care teams highlighted several factors that can contribute to the breakdown of common ground within the critical care team, as well as strategies that can be used to facilitate and support maintenance of common ground.
Before I Forget: How Clinicians Cope with Uncertainty Through ICU Sign-Outs BIBAFull-Text 939-943
  Christopher P. Nemeth; Julie Kowalsky; Marian Brandwijk; Madelyn Kahana; P. Allan Klock; Richard I. Cook
Transitions between shifts in the intensive care unit (ICU) create potential gaps in the continuity of care, and practitioners necessarily rely on distributed cognition to prevent the formation of gaps during work-cycle shift changes. The complexity and uncertainty of each ICU patient's condition require efficient communication between practitioners during transfers between departments or when cycling work through shifts. This study observed twelve unit-level exchanges among six clinicians handing off a 33-bed PICU and step-down unit, then examined them using conversation analysis.
   Our research shows that pediatric ICU fellow sign-outs demonstrate high context sensitivity, compact reference, gestures, and stylized expressions. We find that sign outs account for both what is known and what is not known about a patient's condition, and to assess expectations for the oncoming shift. Uncertainty about patient condition influences handoff content and form. Clinicians change the amount time that they allocate to handoffs based on other aspects of work load, such as rounds or procedures. Clinicians apportion time to discuss individual patients according to the perceived severity and stability of each patient's condition.
   Expertise in hand-off communications depends on the ability to prioritize relevant information and to transfer insights effectively. Relevant, efficient hand-offs significantly affect the ability of clinicians to provide care at the unit level, within and between departments, and across specialties such as intensivists, nurse anesthetists, and anesthesia technicians. Even though they affect patient care quality and continuity, sign outs are not taught but are instead learned on the job. Formal study of, and training in, the conduct of sign outs may benefit both care providers and patients alike.
Implementation of a Patient Safety Collaborative Forum Facilitates Organizational Learning from Medical Error BIBAFull-Text 944-948
  George Blike; Polly Campion; Evelyn Schlosser
Societal awareness of medical errors has rapidly increased following the 1999 publication of the IOM report, To Err is Human (e.g., Kohn, Corrigan & Donaldson, 1999). This report encouraged hospitals to focus on patient safety as a central focus of quality improvement work and to develop proactive approaches to protect patients from medical error. Large hospitals often lack robust mechanisms for reliably identifying patient safety threats, developing effective countermeasures and broadly implementing those measures across the entire healthcare organization. The result is that patient safety activity is heterogeneous across a healthcare organization. Best practices regarding patient safety do not automatically spread horizontally in a hospital, but rather tend to remain isolated. Dartmouth-Hitchcock Medical Center (DHMC) is a large tertiary care facility and academic teaching hospital that self-identified this variation in patient safety processes as an organizational threat to patient safety. Internal reviews identified multiple examples of safety threats countered in one clinical unit, only to have an accident due to the same threat in a clinical unit physically proximate to the first. An Active Error Management (AEM) process utilized in the Department of Anesthesiology that was effective in supporting local learning was identified as a potential vehicle for organizational learning and horizontal spread of patient safety countermeasures. In this report we describe: a) the organizational intervention that was implemented - the Patient Safety Collaborative Forum (PSCF); b) the active error management process that was taught, modeled and coached via this vehicle for organizational learning; c) one example of organizational spread resulting from the PSCF; and finally d) a naturalistic experiment that compares best practice implementation among units that participated in the PSCF to those units that did not.

HEALTH CARE: Teams, Communication, and Culture in Medical Care

Piloting Team Training at Duke University Health System BIBAFull-Text 949-953
  Melanie C. Wright; Xuemei Luo; William J. Richardson; Michael M. Leonard; Susan M. Hohenhaus; Jeffrey M. Taekman; Karen S. Frush
Good team communication and coordination are critical to the safe delivery of health care. Efforts at training students, clinicians, and support staff in team coordination skills are beginning to be implemented across the country. However, there is limited data validating the effectiveness of such programs or highlighting the features that make one program more effective than another. In this paper we present the results of a pilot project to evaluate a team training program at the Ambulatory Surgery Center in the Duke University Health System. Our experiences suggest that (1) initial data collection regarding team coordination attitudes and skills and (2) close follow-up coordination with the clinical organization to implement applicable practice changes are essential components to a teamwork coordination program.
Briefing in the Operating Room A Tool for Enhancing Coordination and Enriching Shared Knowledge Bases BIBAFull-Text 954-958
  Yael Einav; Daniel Gopher; Yoel Donchin
Surgical procedures are complex tasks performed by teams. Their success depends on individual competency and good team coordination. Performance on both individual and team level can greatly benefit from having a shared information basis of patient details, medical status, and planned surgical procedure. Team briefing prior to surgery may pave the way for developing a common reference and a more complete patient and surgery knowledge base. In addition to the obvious role of filling in missing information, broader and more complete knowledge bases can generate proper expectations, facilitate preplanning and improve members' decision making. We report preliminary results from an effort to develop an expanded briefing protocol, and its application in 78 gynecological operations. We compared the frequency of critical events in operations which utilized briefings, with 78 non-briefed operations. We revealed a significant decrease in the number of operations in which at least one team member manifested a lack of knowledge about the patient or the surgical procedure (e.g., allergies, side of operation, type of procedure). There was also a reduction of the number of events in which required equipment was missing or improperly assembled. These types of events increase the risk to the patient. Their reduction attests to the value of conducting briefings to improve team coordination and increase patient safety.
Exploring the Determinants of the Provision of Quality Nursing Care BIBAFull-Text 959-963
  Kamisha Hamilton Escoto; Ben-Tzion Karsh
The purpose of this paper is to present partial results of a model examining the impact of psychosocial work factors on nurses' perceptions of the quality of patient care they are able to provide. Psychosocial work factor variables characterizing the work environment were selected as predictors in the model. The independent variables were job demands, role conflict, task control, resource control, social support, and supervisory support. The dependent variable was a developed measure of perceived quality of care, with items assessing the technical and interpersonal aspects of providing quality care. Using a cross-sectional survey design, data was collected from 120 at a pediatric academic hospital. Results indicate that social support provides a key contribution to nurses' perceptions of quality of care.
The Perception of Just Culture Across Disciplines in Healthcare BIBAFull-Text 964-968
  Terry von Thaden; Michelle Hoppes; Yongjuan Li; Nick Johnson; Angela Schriver
Recently, leading healthcare providers have adopted the principles of just culture to guide their organizations in learning from mistakes to ultimately improve patient safety. To do this, they have adopted an approach to foster active learning wherein members of an organization are encouraged to openly discuss errors without the fear of reprisals. This paper reports results from a just culture survey that was developed at the University of Illinois as part of a patient safety fellowship project. As part of a team, participating hospitals agreed to take part in the study and creation of a "just" culture of shared accountability. Overall results from the survey indicate a slightly positive perception of just culture, but detailed analysis revealed significant differences in the perception of a just culture across professions and departments.
Experimental Evaluation of a Behavioural Marker System for Surgeons' Non-Technical Skills (NOTSS) BIBAFull-Text 969-973
  R. Flin; S. Yule; S. Paterson-Brown; N. Maran; D. Rowley; G. Youngson
Non-technical skills provide a critical underpinning for good surgical practice, but they must be trained and assessed according to properly developed skills frameworks and validated measurement tools. The NOTSS (Non-Technical Skills for Surgeons) skills taxonomy was developed from cognitive task analysis with subject matter experts and has been reported previously. It comprises five categories (situation awareness, decision making, task management, communication and teamwork, and leadership) divided into fourteen elements. The aim of the present study was to evaluate this as a behavioural rating system. An evaluation was conducted with 44 consultant (attending) surgeons who were trained to use the prototype NOTSS system and then rated surgeons' behaviours in six videos of simulated surgical scenarios. Evaluation results indicate that the system is complete, the skills are observable, and can be rated with approaching acceptable levels of agreement. Responses regarding initial usability were positive.

HEALTH CARE: Modeling and Decision Making in Health Care

The Influence of Resource Pressure on Medical Treatment Decisions BIBAFull-Text 974-978
  Marc Resnick; Stephane Timothee
Due to rapidly increasing costs in the US health care system, there is pressure on physicians at all levels to minimize the cost of treating patients. There is a risk that these pressures may lead to a reduction in the overall quality of care. This paper describes an investigation into the effects of resource pressure on physicians' perceptions of the level of care they are able to provide and their actual treatment decisions. The results generate questions that are critical to resolve for the future of the health care system. The first study demonstrated that correctional patients were provided less care than free patients across a range of treatments. These differences were magnified for treatments that require greater resources. The second study revealed that these differences may be linked to the pressure placed on physicians, especially in early residency, to conserve resources for patients that are seen as less likely to comply with the recommended regimen of care. There is also evidence that some explicit bias may be present.
Risk and Recovery in Complex Medical Domains: Computational and Graphical Models of Performance BIBAFull-Text 979-983
  Meghan M. Dierks
Medicine is a complex, safety-critical and highly interactive system. Despite efforts to provide safe, effective care, adverse events still occur - clinicians make diagnostic and therapeutic errors, system constraints impact the coordination and delivery of care and patients suffer unexpected complications and injuries. Our current understanding of the nature of medical adverse events, and our ability to develop durable preventative or mitigating strategies has been hampered by somewhat out-dated and inadequate models of clinical risk, which focus almost exclusively on patient factors, provider factors or the specific clinical procedure being performed. Absent from such models are the interactions and interdependencies between different system components (staffing, instrumentation, protocols, procedures, access to and quality of information, communication modes, and scheduling cycles, system-wide volume and acuity, throughput pressures), an understanding of the reliability of such components under different operating conditions and the significance of failure during different phases of clinical care. This paper describes the use of computational and graphical models to improve our understanding of medical risk by modeling complex interactions between clinical subsystems and variations in risk across different phases of clinical care. Many of the submodels developed here are generalizable across a broad range of other healthcare settings.
Acquiring Health Information: Interpreting Terminology and Reported Search Sources BIBAFull-Text 984-988
  Rebecca S. Green; Jennifer A. Cowley; Michael S. Wogalter
This study examines two main topics concerning the acquisition of health-related information. One was to explore how people interpret some relatively common terms used in the labeling of prescription and non-prescription drugs, specifically focusing on the terms "family history" and "MAOI." The second is to determine the sources people report they would use to gather health information, or specifically, where they would go to get health-related information associated with an iron supplement. The results show that "family history" evoked an interpretation of older more than the younger blood relatives. Few persons could report what monoamine oxidase inhibitor (MAOI) meant. People report being more likely to consult the Internet or a health professional than any of the other sources listed. Implications for better health-related information acquisition through better-designed warning systems are discussed.
The Patient Technology Acceptance Model (PTAM) for Homecare Patients with Chronic Illness BIBAFull-Text 989-993
  Calvin K. L. Or; Ben-Tzion Karsh
Health information technologies are increasingly being used to support patient self-management during the home recovery process for chronically ill homecare patients. While in theory these technologies may provide better access to information and resources to patients, thus possibly improving health outcomes, there is a risk that patients will not use the technology. As such, it is essential to understand what causes patients to accept technologies prior to implementation. Existing technology acceptance models may not apply to an elderly patient population because most models were developed studying healthy college students or healthy employees. The elderly, and specifically elderly with chronic illnesses, may accept or reject technology for reasons different from those previously identified. This study developed the patient technology acceptance model to better understand what key factors predict patient intention to use health information technologies.
Modeling Surgical Resident Performance BIBAFull-Text 994-998
  Sara Waxberg; Caroline G. L. Cao
The goals of this work were to evaluate the methods used for assessing surgical residents and to model surgical resident performance. Currently, residents are evaluated by the attending surgeons using a one-page paper evaluation form after each rotation in a particular department. These subjective questionnaires require the evaluators to rate residents in competency areas that are thought to define a successful surgeon. An electronic database was created from resident performance records collected over the past 33 years from the Department of Surgery at the Tufts-NEMC. A usability study examined the effectiveness of the design of the evaluation form and the competency measures. Analysis showed nine changes in format between 1972 and 2005, varying in the competencies rated and rating scales used. Regression analysis was used to model the performance of surgical residents. Results showed that judgment (p < 0.0001), initiative (p < 0.0001), and reaction to stress (p = 0.0206) were significant predictors of a successful outcome. This model may be used to predict the success of new residents and possibly target weaknesses in the surgical education curriculum.

HEALTH CARE: Adverse Events and Reporting Systems in Health Care

A Methodology to Identify Systemic Vulnerabilities to Human Error in the Operating Room BIBAFull-Text 999-1003
  Kenneth H. Funk; Toni Doolen; Javier Nicolalde; James D. Bauer; David Telasha; Miriam Reeber
A methodology to identify systemic vulnerabilities to human error in surgical procedures was developed and applied to the initial stages of laparoscopic cholecystectomy. A database of generic human tasks and errors was developed and applied to four task descriptions developed from an IDEF0 model of the process. Over 30 vulnerabilities to human error were identified and prioritized.
Ward: An Exploratory Study of an Affective Sociotechnical Framework for Addressing Medical Errors BIBAFull-Text 1004-1008
  William Lee; Woodrow W. Winchester; Tonya L. Smith-Jackson
Affective states influence judgment, motivation, risk perceptions, and sense of well-being. Clinicians constantly struggle with negative affective states due to the nature of their work. We propose our framework, the Wearable Avatar Risk Display (WARD), to investigate medical errors from the perspective of affective states' influence. WARD is a dynamic and multimodal mobile affective system that aims for delivering information meaningfully and humanely to clinicians according to their affective states. WARD originates from sociotechnical systems theory and serves two purposes: (1) To guide the development of a test bed of avatars with lifelike behaviors (affective avatars) and (2) To investigate the interplay of clinicians' affects, risk perceptions, and decision-making ability in a healthcare setting. We recently piloted a small exploratory study using Mood Induction Procedures (MIPs), Iowa Gambling Task, and affective avatars to investigate participants' decision-making pattern. Our results indicated that participants did not benefit from our avatars currently. However, correlations analysis and suggestions from participants revealed that there is potential for affective avatars in critical or emergency situations.
Categorizing Adverse Medical Device and Medication Event Frequency BIBAFull-Text 1009-1013
  Kristopher Thornburg; Geb Thomas; Scott Draper
Much of the research interest in reducing adverse medical events emphasizes medical device interfaces and software design. Infusion pump programming has enjoyed particular research attention. This study categorized 1260 adverse medical event reports at three Midwestern hospitals. Although an important contributor, infusion pump programming contributes to fewer adverse events than the amount of literature implies. More common problems involve opening the intravenous infusion piggyback clamp and medication identification.
A Reporting System of Difficulties and Hazards in Hospital Wards as a Guide for Improving Human Factors and Safety BIBAFull-Text 1014-1018
  Ido Morag; Daniel Gopher
Contemporary efforts for improving healthcare safety are almost exclusively dependent on the study of adverse events as their primary information source. Investigations of adverse events have had an important role and contribution to the recognition of the magnitude of the healthcare problem, but are of a limited scientific value. Error investigations are the wisdom of hindsight, based on partial and biased sample, lacking base rate reference and distorted by reporter's memory and interests. This paper describes an alternative approach based on self reports of medical staff, on daily reoccurring hazards and performance difficulties, representing human factors and safety aspects. Reports are evaluated by a human factors team, and corrective steps are proposed, and backed by management. We describe the logic and elements of the new approach, and bring results from four wards belonging to two hospitals. These results are compared with data obtained in 5 years, using conventional incident reporting systems.
Protocol Violations during Medication Administration in Pediatrics BIBAFull-Text 1019-1023
  Samuel J. Alper; Ben-Tzion Karsh; Richard J. Holden; Matthew C. Scanlon; Neal Patel; Rainu Kaushal
The paper uses a new measure of protocol violations to explore the extent of violations in the medication administration process. 203 nurses in three units of a free-standing pediatric hospital were provided with a survey assessing violations in the medication administration process; 120 nurses responded for a response rate of 59%. Violation data were collected for three stages of the medication administration process: matching medications to the medication administration record, checking patient identification, and documenting administration. The percentage of nurses who reported violating protocol in the medication administration process ranged from 8.4% to 30.2% in routine situations, and from 32.2% to 53.0% in emergency situations. Violations in the medication administration process may lead to medication errors. To improve medication safety, efforts should be taken to discover the system deficiencies that produce such frequent violations. System redesign should then address these deficiencies.

HEALTH CARE: Modes of Perception in Medical Tasks

The Performance Effects of Color-Contrasting Shadows on Laparoscopic Surgery BIBAFull-Text 1024-1028
  Ryan Shimotsu; Caroline G. L. Cao
The viewing limitations inherent in laparoscopic surgery, severely limit depth perception compared to open surgery, sometimes leading to internal trauma caused by the laparoscopic instruments. Recently, the effects of shadows in laparoscopy have been studied and have shown promising results. Previous studies have found that the addition of shadows can improve performance in tasks under laparoscopic condition. Aiming to further improve depth perception in laparoscopic surgery, this study tested the effect of color-contrasting shadows on performance in a depth perception-dependent laparoscopic task. It was hypothesized that the added contrast of colored shadows should make them easier to see on the dark red backgrounds found in the body, thus improving performance. Twenty-four novice participants were included in the study, which compared performance under no shadows, black shadows, and colored shadows on two differently colored backgrounds. In all conditions, the task was performed on an oscillating platform. Results from this study showed that the presence both the colored shadows and the black shadows improved performance compared to no shadows, but the colored shadows did not provide a significant advantage over black shadows.
Vibrotactile Feedback Enhances Force Perception in Minimally Invasive Surgery BIBAFull-Text 1029-1033
  Ryan E. Schoonmaker; Caroline G. L. Cao
Distorted force feedback in minimally invasive surgery causes the procedure to become more difficult for the surgeon. A simulated tissue probing task was designed to test the hypothesis that vibrotactile feedback can enhance one's ability to differentiate tissue softness, and control the forces being applied to tissue. The two independent factors in the study were vibration feedback, consisting of four levels (continuous, fine-step, crude-step, and no vibration), and audibility, consisting of two levels (on and off). The results demonstrated that with the aide of vibration the absolute probing depth error was reduced (5.7mm - no vibration, 3.65mm - fine step), and the average maximum force applied was reduced (1.32 N - no vibration, 1.04 N - fine step). Additionally, the normalized time to detection (0.93s/s audible, 1.10s/s non-audible) and maximum force (1.16 N - non-audible, 1.08 N - audible) was reduced in the audible condition. These results indicate that vibrotactile stimulation is a viable substitute for force feedback in simulated minimally invasive surgery.
Integrating Instructional Strategies and Haptic Technologies to Enhance the Training Efficacy of an Army 91W (Combat Medic) Medical Skills Training Simulation BIBAFull-Text 1034-1038
  Dawn L. Riddle; Jennifer Fowlkes
This paper describes the design of HapMed, a haptics-based simulation system for training US Army 91W10 combat medic tasks. Particular emphasis is placed on a cognitive engineering design methodology for integrating haptic technologies and instructional design strategies to enhance HapMed training effectiveness. The unique design of HapMed also addresses the Army's critical need for a modular, field deployable training system that bridges the gap between civilian first responder training and combat casualty care.
Do mnemonics help nurses learn melodic medical equipment alarms BIBAFull-Text 1039-1043
  Alexandra N. Wee; Penelope M. Sanderson
We tested the melodic alarms and mnemonics proposed in the international standard for alarms used in medical electrical equipment (IEC 60601 -1 -8) for learnability and discriminability, with 14 registered nurses over two days, approximately a week apart. Two learning modes (Mnemonics and No Mnemonics) were examined in computer administered tests. The first experimental group was supplied with mnemonics while the second group was not supplied with a strategy. On Day 1, participants were introduced to the alarms. On Day 2, participants were tested and then allowed to relearn the alarms in a similar way to Day 1. The mean accuracy across all alarms other than the General alarm was poor (44% correct). Only one participant reached the learning criterion by the end of Day 2. Furthermore, participants with formal musical training identified the alarms with greater accuracy than those without (p=0.004). Our findings indicate that the identified problems need to be addressed before these alarms are introduced in practice.
Effects of Visualization Tools on Cardiac Telephone Consultation Processes BIBAFull-Text 1044-1048
  Yukari Enomoto; Catherine M. Burns; Kathryn Momtahan; Whynne Caves
An Ecological Interface Design approach was employed to analyze and extract information for a Decision Support System (DSS) for cardiac nurses' telephone consultation processes. Information visualization techniques were explored to overcome the complexity of the information space. Three visualization prototypes, Bar, Polar, and Clock Symptom Maps, were designed based on the Work Domain Analysis and the identified strategies from a Cognitive Work Analysis. An experiment was conducted to evaluate the effects of these visualization tools using low-fidelity prototypes. Static images of patient symptom maps were used to mimic the final information space. Positive effects of the visualization tools were observed compared to a text list of presented problems, especially when the decision problems were more complex. The results are encouraging with regards to the integration of graphical symptom maps into DSSs.

HEALTH CARE: Workflow, Interruptions, and Information Exchange in Health Care

An Empirical Investigation of Surgical Flow Disruptions and their Relationship to Surgical Errors BIBAFull-Text 1049-1053
  Douglas A. Wiegmann; Andrew W. ElBardissi; Joseph A. Dearani; Thoralf M. Sundt
Surgical flow disruptions can significantly increase the probability of surgical errors. However, little is known about the frequency and nature of surgical flow disruptions, making the development of evidence-based interventions extremely difficult. The goal of this project was to prospectively study surgical errors and their relationship to surgical flow disruptions within the context of cardiac surgery. A trained observer recorded surgical errors and flow disruptions during 31 cardiac operations over a three-week period. Flow disruptions were then reviewed and analyzed by an interdisciplinary team of surgical and human factors experts. Results revealed that flow disruptions consisted of teamwork/communication failures, equipment and technology problems, extraneous interruptions, training-related distractions, and resource accessibility issues. Errors increased significantly with increases in flow disruptions. Teamwork/communication failures were the strongest predictor of surgical errors. These findings provide preliminary data for developing evidenced-based error management and patient safety programs within cardiac surgery.
Evaluating the Use of Flowsheets in Pediatric Intensive Care to Inform Design BIBAFull-Text 1054-1058
  David T. Bauer; Stephanie A. Guerlain; Patrick J. Brown
Flowsheets are central artifacts of information collection and exchange to support the monitoring and diagnosis of patient status in the pediatric intensive care unit. This study used field observations to examine the design and use of flowsheets. Strengths of the current paper document include portability, bundling of related data, and allowing for notes and annotations. However, the static nature of the paper document requires that users manually calculate and carry over important trends and relationships. Spatial constraints of the paper document make it necessary to squeeze data into a small space with data sometimes being difficult to read. Electronic flowsheets have the potential to overcome these limitations and introduce new features, but depending on their design, may eliminate the strengths of the original system. Studying actual practices in the work environment yielded insight into the use of the document to inform the design of an electronic flowsheet system.
Task Coordination and Group Foraging in Healthcare Delivery Teams BIBAFull-Text 1059-1063
  Sandra K. Garrett; Barrett S. Caldwell
In healthcare, the team of medical providers must cooperatively seek the information and physical resources needed in order to be able to attend to patients in a timely and effective manner. Foraging theory is one field that may help describe the strategies used to acquire resources; however, the concept and definitions of foraging must be expanded to appropriately describe the team coordination activities in a high-risk, time-limited, event-driven environment. The issues of resource handoffs and the coordination of multiple task demands with shifts between tasks become crucial to the overall performance of the healthcare delivery system. Task interleaving and parallel work load issues are being investigated to distinguish these actions from the issue of workload interruptions emphasized in previous research.
Fixation and Attention Allocation in Anesthesiology Crisis Management: An Abstraction Hierarchy Perspective BIBAFull-Text 1064-1067
  T. Jason Hall; Jenny W. Rudolph; Caroline G. L. Cao
The abstraction hierarchy analysis tool developed by Vicente and Rasmussen (1992) for Ecological Interface Design (EID) provides an in depth understanding of work domain constraints and information requirements. ELD and work domain analysis (WDA) have been successfully applied in several fields. However, application in the medical domain has proven to be much more difficult. This study examines the relationships between three components within the OR: the surgical team, medical equipment, and the patient. It is hypothesized that crisis management failure in the OR is due to attentional mis-allocation and can be undone by re-directing team members' attention to the appropriate level of information structure. We propose a novel structure, based on existing work domain models for the operating room, to analyze the behavior of OR teams and map their attention allocation within the abstraction hierarchy to explain fixation during medical problem solving and crisis management.
Characterization of Sign-Out in Pediatric Acute Care Wards to Inform Process Improvement BIBAFull-Text 1068-1072
  Richard M. D. Sledd; Ellen J. Bass; Stephen M. Borowitz; Linda A. Waggoner-Fountain
Physician sign-out is a mechanism for transferring patient information, responsibility, and authority from one set of hospital caregivers to another at shift changes. This project characterized the information exchanged between physicians during 15 sign-outs, and analyzed data from 158 post-call resident surveys. Ten categories of patient information were developed to characterize the exchanged information. Of the ten categories of patient information, no single category was discussed for every patient. The information critically important to discuss during sign-out was often the least covered, as residents discussed the patient's current physical condition for only 35% of the patients, current medications for only 63% of patients, and contingency plans for possible scenarios for only 17.7% of patients.
   On average, residents discussed 14 patients during each sign-out, with the average sign-out lasting 35 minutes (2:28 minutes/patient). Of the total sign-out duration, approximately 23% of the time was spent discussing matters not related to patient care. Of the time spent "on-task", 32.2% was spent on patient background, which could be obtained from other data sources. Very little time was spent discussing information which may not be available elsewhere, such as what actions, both planned and contingency, should occur overnight. Such information only received 12.1% of the sign-out time.
   49 out of 158 resident surveys (31.0%) revealed that residents experienced an event while on call that they were unprepared to handle. Of those cases, 82% were the result of missing information.
   These data create a baseline understanding of sign-out which should be used to inform potential process and training improvements to ensure that the appropriate information is discussed for each patient.

HEALTH CARE: Patients as Partners in Treatment

Facilitating At-Home Colorectal Screening: The Effect of Cognitive and Motivational Instruction Features on User Perceptions and Intentions BIBAFull-Text 1073-1077
  Markus A. Feufel; Tamera R. Schneider; Hans J. Berkel
Fecal Occult Blood Tests (FOBT), which screen for colorectal disease, like other medical at-home testing procedures require users to follow complex instructions that need to be executed carefully for valid results. If instructions are difficult to understand, they may hamper health behavior engagement. This paper describes two experiments that tested the influence of human factors engineering guidelines and motivational instruction features on user perceptions and intentions. Results show that instructional features influenced both user perceptions and intentions. In Experiment 1 the motivational enhancement increased intentions for screening among college students. In Experiment 2, which included the targeted FOBT population (adults over 50), the combination of human factors guidelines and motivational features maximally increased requests for FOBT screening kits. By improving these features we may be able to facilitate FOBT screening and insscrease compliance rates.
Doctor-Patient Communication: Guidelines for Improvements BIBAFull-Text 1078-1082
  Jamye M. Hickman; Kelly E. Caine; Aideen J. Stronge; Richard Pak; Wendy A. Rogers; Arthur D. Fisk
Effective communication between patients and their healthcare providers is essential to positive health outcomes. Older adults may be at a disadvantage during communication exchanges due to age-related sensory declines and cognitive changes. Understanding the role of these age-related changes may lead to interventions that will ameliorate the disadvantages older adults face in the health communication process. Twenty-four older adults were interviewed to obtain an understanding of the difficulties older adults face during health communication. The findings suggest that older adults do have health communication problems. They are, however, able to generate strategies to solve these problems when problems are presented in hypothetical scenarios. Based on the findings, a brochure was developed to provide strategies and guidelines to help anticipate and resolve health communication problems.
How Patients Understand Diabetes Self-Care BIBAFull-Text 1083-1087
  Katherine D. Lippa; Helen Altman Klein
Millions of people with diabetes must control their blood glucose system through diet, medication, and exercise. To learn how patients understand this daunting task, we conducted Cognitive Task Analysis interviews with 20 participants with type II diabetes. The interviews queried initial education, experiences with self-care, understanding of the disease, and treatment adherence. Participants who showed greater expertise in their articulation of problem detection strategies, functional relationships, and problem solving strategies were more effective self-managers. Several mental models of diabetes self-management were identified. Human Factors advances that have helped pilots control planes, may also help patients to develop functional models of blood glucose control and cope with the complexities of self-care. These advances may also help people facing other chronic medical conditions and complex life challenges.
Medication Adherence: Many Conditions, A Common Problem BIBAFull-Text 1088-1092
  Devorah E. Klein; Gretchen Wustrack; Amy Schwartz
The problem of adherence - why people fail to follow therapies intended to improve their health - has long bedeviled researchers in medicine, public health, nursing, pharmacology, psychology, and beyond. Most studies have focused on solving problems surrounding a specific condition (such as diabetes) or behavior (such as smoking cessation). This proposal presents a generalized, cross-condition model - the Adherence Loop model - that describes the role of beliefs, knowledge, and actions for designing better adherence programs. The model is based on studies from 4 diverse conditions: multiple sclerosis (MS), weight loss, osteoporosis, and erectile dysfunction (ED). The model suggests ways to support the design process and create programs, tools, and environments to promote adherence by better understanding patients' journeys and mental models of their conditions.
Patients as Partners in Treatment BIBAFull-Text 1093-1094
  Helen Altman Klein
This symposium is motivated by the disparity between the careful and productive Human Factors research now devoted to hospitals and professional equipment on the one hand and the more limited attention given to the daunting challenges facing patients and potential patients outside the formal health care system. Patients must use health-screening resources; seek and understand medical advice; select, initiate, and adhere to health maintenance regimes; and follow home-based treatments often with little feedback or supervision. For chronic disorders, treatment demands can last a lifetime. For the elderly, age related barriers complicate interactions with professionals. This symposium shows how Human Factors is now helping people become more active and effective partners in detection, prevention, and treatment. The research presented will span varied disorders with strikingly different adherence and management demands. This technical, interface, and instructional complexity calls for a more integrated approach to supporting patients as they manage their health.

HEALTH CARE: Reports from the Field: Evaluation of Medical Equipment, Materials and Methods

Usability Evaluations as Part of the Procurement Process: Case Study of Hospital Point of Care Carts BIBAFull-Text 1095-1098
  Emily Seto; Carol Roach; Anjum Chagpar; Andrew MacDonald
Typical hospital procurement processes do not include a formal product evaluation beyond a short trial and soliciting of user preference. Usability evaluations can be an informative aid to determine the best match for a particular healthcare institution. The ergonomics of three short-listed point of care carts were evaluated by having hospital staff use the carts in realistic scenarios and environments. The carts'maneuverability, ease of recharging the point of care device, adequacy of space (storage and workspace), adjustability, keyboard/mouse position, suitability of use in the daily practice, and size were assessed. Usability testing of the point of care carts provided many insights into their strengths and weaknesses, such as whether or not they provided enough storage space for transporting medication to the patient bedside. The results of usability evaluations could be a critical factor in deciding which products can be successfully integrated into a particular healthcare institution.
Human Factors Evaluation of Automatic External Defribillators in a Hospital Setting BIBAFull-Text 1099-1102
  Munira Jessa; Joseph Cafazzo; Anjum Chagpar; Richard Cooper; Randy Wax; Tony Easty
Automatic External Defibrillators (AEDs) can be used in hospitals to facilitate early defibrillation. We sought to find the features of a hospital AED that would be the most usable and thus provide straightforward and easily accessible resuscitation. Three different vendor AEDs were evaluated in a three-part human factors evaluation employing heuristic analysis, user testing, and failure modes and effects analysis. Through each analysis we identified the critical AED features of interest for in-hospital use. The highest-rated features were compiled and interpreted to determine the best AED features for in-hospital use. It is necessary to consider all aspects of medical device design in a practical sense to ensure the overall safety and efficacy of the device. Training may address some aspects of poor design, but cannot address unanticipated usability issues. Additionally, issues arising due to infrequent use of equipment can be evaluated using the training and evaluation methods employed in this study.
Pinch Forces and Instrument Tip Forces during Periodontal Scaling BIBAFull-Text 1103-1106
  Hui Dong; Alfredo Villanueva; David Rempel
The prevalence of upper extremity musculoskeletal disorders, including carpal tunnel syndrome (CTS), are elevated among dental practitioners, especially dental hygienists. An important risk factor for these disorders is forceful pinching; however, the pinch forces and instrument forces during scaling are unknown. Six dentists and 6 senior-year dental students were recruited to use a specially designed instrument while performing their usual dental scaling on patients. Thumb pinch force was measured by a pressure sensor, while the forces developed at the instrument tip were measured by a 6-axis load cell. Dental students applied greater mean peak pinch force (35.7 ± 3.8 N) compared to dentists (24.5 ± 4.1 N) (p = 0.001). The peak forces generated at the instrument tip were higher among the dentists. Increased experience in periodontal scaling leads to the application of less pinch force to accomplish scaling. Nonetheless, the applied peak pinch forces in both groups are high and pose a risk for the development of musculoskeletal disorder of the distal upper extremity.
Development of a Group-Based Ergonomic Assessment Strategy Tor Characterizing Physical Workload in Healthcare Workers BIBAFull-Text 1107-1111
  Jon Boyer; Jamie Tessler; Jungkeun Park; Laura Punnett
Museuloskeletal disorders of the back are a widespread problem in the healthcare sector and have been associated with trunk bending, twisting, and manual handling. The objective of this study was to conduct a group-based exposure assessment of trunk postures, loads, and work activities for use in epidemiology studies of back disorders in healthcare workers. All job titles in 4 healthcare facilities were assigned to a-priori ergonomic exposure groups to guide the sampling protocol. Ergonomic exposures were collected through direct observation of a population subset (n=180), in 94 job titles, at 90-second intervals, using a modification of the PATH method. A total of 23,071 direct observations were collected over 225 observation periods (l-8hrs). Exposures were analyzed by job groups and group exposures were ranked by their location relative to underlying distributions. A final set of 8 similar exposure groups were produced through combination of qualitative and quantitative methods. The semi-quantitative group ranks explained postural and load handling exposure profiles in nursing home and hospital workers.
Eye Tracking Study on the Impact of the Manufacturer's Logo and Multilingual Description on Drug Selection Performance BIBAFull-Text 1112-1116
  Agnieszka Bojko; Kevin Buffardi; Gavin Lew; Edmond Israelski
The object of the study was a proposed standardized format for Abbott prescription drug labels as it would be applied to domestic and international cartons. We focused on two label elements which were not investigated in our previous study (Bojko et al., 2005) - an additional logo and multilingual description of the drug carton contents, and their potential effect on drug selection performance. Twenty-two pharmacy practitioners completed a series of tasks that involved locating a particular drug among several others. Eye movement measures (fixation count, mean fixation duration, and pupil diameter) and conventional performance metrics (error rate and time on task) were collected. The results suggested that neither the Abbott "a" nor the additional languages affected participants' accuracy, search and information processing efficiency, or mental workload. We discuss additional factors for consideration in a follow-up study to further investigate the effect of multilingual descriptions on user performance.

HUMAN PERFORMANCE: Approaches in Human Performance Modeling

Queuing Network Modeling of a Real-Time Psychophysiological Index of Mental WorkloadP300 Amplitude in Event-Related Potential (ERP) BIBAFull-Text 1117-1121
  Changxu Wu; Yili Liu
The P300 amplitude of a secondary task is found to decrease in dual task situations compared with the corresponding single task situation of performing the secondary task alone, and is regarded as an effective real-time index of mental workload. In this article we describe a successful extension and application of the queueing network human performance model to quantify and model this major finding in P300, based on the neurophysiological mechanisms of P300. A comparison of the simulation results of the model with the corresponding experimental results in the literature indicates that the model quantifies human performance and the change of P300 amplitude in single and dual task conditions accurately. The model has not only a solid basis in its biological mechanism, but also potential value in real time workload prediction and application. Further developments of the model in simulating other dimensions of mental workload and its potential applications in adaptive system design are discussed.
Building predictive human performance models of skill acquisition in a data entry task BIBAFull-Text 1122-1126
  Wai-Tat Fu; Cleotilde Gonzalez; Alice F. Healy; James A. Kole; Lyle E. Bourne
This paper presents a predictive model of a simple, but important, data entry task. The task requires participants to perceive and encode information on the screen, locate the corresponding keys for the information on different layouts of the keyboard, and enter the information. Since data entry is a central component in most human-machine interaction, a predictive model of performance will provide useful information that informs interface design and effectiveness of training. We created a cognitive model of the data entry task based on the ACT-R 5.0 architecture. The same model provided good fits to three existing data sets, which demonstrated the effects of fatigue with prolonged work, repetition priming, depth of processing, and the suppression of subvocal rehearsal. The model also makes predictions on how performance deteriorates with different delays after training, how different amounts of rehearsal during training affect retention, and how re-training helps retention of skills.

HUMAN PERFORMANCE: Approaches in Human performance modeling

Modeling the Task Environment: ACT-R and the Lens Model BIBAFull-Text 1127-1131
  Sarah Miller; Alex Kirlik
Human factors requires modeling techniques that capture how cognition and behavior are sensitive to environmental design. As such, techniques such as Anderson's rational analysis and Brunswik's lens model framework should be of interest to human performance modelers because they provide ways to analyze tasks and behavior as adaptive to environmental structure. We briefly describe both techniques and contrast them in the context of modeling visual search behavior. We conclude that these techniques can provide complementary resources for human performance modeling in human factors.

HUMAN PERFORMANCE: Approaches in Human Performance Modeling

Using Petri Nets for Gibson's Affordances: First Steps into Perception-Based Task Analysis BIBAFull-Text 1132-1136
  Hari Thiruvengada; Ling Rothrock
In this paper, we introduce the notion of affordance proposed by Gibson, and provide a computational formalism based on Petri Nets (PNs) for conducting perception-based task analysis. Gibson used affordance to refer to what an environment offers an animal for either ill or good. Since then, affordance has been widely adopted and used in several areas such as human computer interaction, mobile robotics, etc. We argue that Petri Net provides the appropriate framework for performing a perception-based task analysis (PTA) as it helps investigate the task from an ecological perspective based on concepts such as affordance, effectivity and actualizations. Additionally, Petri Net can be used to study behavioral properties such as reachability, boundedness and liveness, which relate to the perception-based task. We illustrate how the ecological concepts can be modeled using the proposed PN formalism with reference to a driving task. We conclude that Petri Net is a very useful tool for conducting perception-based task analysis.
Analysis of Human Postural Control during Spontaneous Sway using an Optimal Control Model BIBAFull-Text 1137-1141
  Xingda Qu; Maury A. Nussbaum; Michael L. Madigan
Models of human postural control aid in understanding human capabilities and limitations, and may facilitate a reduction in injuries related to loss-of-balance. Such a model is presented here to simulate and interpret the postural control system during spontaneous sway. The human body was represented by a simple inverted pendulum, with the neural controller assumed to be an optimal controller that generates spontaneous sway according to a certain performance criterion. In order to accurately simulate existing experimental data, an optimization procedure was used to specify the set of model parameters. Ten independent simulations were performed for both young and older adults. Aging effects were then analyzed based on the simulation results. The results showed that this model was able to simulate some center-of-pressure measures reported in experimental studies, and indicated potential changes in postural control mechanisms caused by aging.

HUMAN PERFORMANCE: Exploring Behavior with Human Performance Models

Juggling Multiple Tasks: A Rational Analysis of Multitasking in a Synthetic Task Environment BIBAFull-Text 1142-1146
  Hansjorg Neth; Sangeet S. Khemlani; Brittney Oppermann; Wayne D. Gray
Tardast (Shakeri 2003; Shakeri & Funk, in press) is a new and intriguing paradigm to investigate human multitasking behavior, complex system management, and supervisory control. We present a replication and extension of the original Tardast study that assesses operators' learning curve and explains gains in performance in terms of increased sensitivity to task parameters and a superior ability of better operators to prioritize tasks. We then compare human performance profiles to various artificial software agents that provide benchmarks of optimal and baseline performance and illustrate the outcomes of simple heuristic strategies. Whereas it is not surprising that human operators fail to achieve an ideal criterion of performance, we demonstrate that humans also fall short of a principally achievable standard. Despite significant improvements with practice, Tardast operators exhibit stable sub-optimal performance in their time-to-task allocations.
Towards the Shape of Mental Workload BIBAFull-Text 1147-1151
  Daniel N. Cassenti; Troy D. Kelley
Mental workload is a measure of how much mental effort a person devotes to one or more tasks. In two experiments, we investigated the effect of multiple identical tasks on human performance in terms of both accuracy and response time for a visuo-spatial task set and an auditory task set. The findings showed that participants performed linearly worse on some measures of performance when the number of tasks increased, while other measures showed two distinctive variations on this linear decrease in performance. We discuss these results in terms of their effect on the traditional linear representation of workload in IMPRINT (IMproved Performance Research INtegration Tool, Archer & Adkins, 1999), a task-based human performance modeling system.
A Few Seconds of Equation Reading: A Process Model of Equation Reading and its Applications BIBAFull-Text 1152-1155
  Douglas J. Gillan; Paula Barraza
A model, based on research using think aloud, memory recognition and recall, response time, and eye tracking methods, describes cognitive processes in equation reading. Equation reading involves (1) 300 msec fixations during which the reader extracts features to identify the symbols - numbers, operators, parentheses - as attention shifts across 2 - 3 symbols, and (2) short saccades that often end on numbers. The reader identifies the end of a multidigit number by a space, leading her to identify a sequence of numerals as a one-, two- or three-digit number. Parentheses, rarely fixated and poorly recalled, help direct the flow of reading. Parenthetical expressions are solved and stored separately. Readers backscan approximately as frequently they forward scan through equations, possibly to construct a representation of the equation structure as they read it. The model of the processes of equation reading by sighted persons has been useful in designing an auditory browser for blind readers.
A Computational Model of Eye Movements as Cyclic Top-Down and Bottom-Up Processes BIBAFull-Text 1156-1159
  Ji Hyoun Lim; Yili Liu
Studying eye movement not only has theoretical significance in understanding visual attention, but also practical relevance to a diverse range of human factors applications such as aviation, driving, and display design. This article presents the use of a computational model of eye movement based upon reinforcement learning to examine the cyclic influences of top-down and bottom-up processes. The first study showed that different policies obtained from different goals in viewing a picture produced different types of eye movement patterns. The second study showed that the feedback information from each saccadic eye movement could be used to update the model's eye movement transition matrix, which led to different patterns in the subsequent saccade in a visual search task. These two studies demonstrate the value of an integrated reinforcement learning model in explaining both top-down and bottom-up processes of eye movement within one computational model.
Visual Model of Modulation Transfer Function for Assimilation Phenomenon by Gaussian Filter BIBAFull-Text 1160-1164
  Takako Nonaka; Morimasa Matsuda; Tomohiro Hase
This paper describes an assimilation phenomenon on sample images and proposes an analytical model by Gaussian filter for this phenomenon. First, the frequency spectrum of a sample pattern is formulated by the discrete Fourier transform. Next, human visual characteristics are formulated by Gaussian band pass filter. Thirdly, the concept of a noise level is introduced. Then, the two-dimensional model of the relations is discussed qualitatively and quantitatively. Finally, the verification experiments by subjective evaluation and measuring the visual distance was conducted. The results of the proposed model are very similar to the results of subjective evaluation under the reasonable conditions; an attenuation coefficient of 200 and a cutoff frequency of 5 cycles/degree in the visual BPF model, and a noise level of 40 dB.

HUMAN PERFORMANCE: Tools for the Human Performance Modeler's Toolkit

Putting the Brain in the Box for Human-System Interface Evaluation BIBAFull-Text 1165-1169
  Michael D. Fleetwood; Christian Lebiere; Rich Archer; Rebecca C. Y. Mui; Mala Gosakan
We describe a tool, the GRaph-Based Interface Language tool (GRBIL), in which developers can easily design, construct, and evaluate system interfaces. The GRBIL system allows a designer to graphically define a system interface and walk through a set of operator goals for using the interface. To evaluate the interface, the system automatically generates a cognitive model of a system operator (built in the ACT-R cognitive architecture), which provides metrics of time on task and potential errors. In addition, the system allows the easy incorporation of dynamic models of the external world in order to evaluate interfaces that involve continually changing environments. We discuss the on-going validation of GRBIL as it is used to evaluate a robotics operator control unit.
Intelligent Multimodal Signal Adaptation System (IMSAS) BIBAFull-Text 1170-1174
  Julie Bzostek; Ron Small; Timothy Bagnall; Brett Walters
As cockpits become more complex, pilots must monitor more data in the normal operation of an aircraft including the states of automated systems. Our objective was to demonstrate that pilots can achieve a greater level of situational awareness when key information is presented in an untaxed modality at the proper time. We modeled a portion of a flight and developed predictor values that we could use to calculate whether or not a pilot noticed an alert. We first recorded some baseline measures of these times, and then used MIDA (Multimodal Interface Design Advisor) to suggest optimal modalities for the signals. We then tested a proposed system that would anticipate a violation (i.e., an air speed violation) and present the appropriate signal with some lead-time. IMSAS (Intelligent Multimodal Signal Adaptation System) continuously assesses the cockpit environment, forecasts airspeed state into the future, and, if it recognizes a need to communicate to the pilot situational information, determines the proper modality in which to present a signal. This study showed an improvement in the reaction time to a signal of over 50% over the baseline. Although further research is needed, this study shows that IMSAS has the potential to improve pilots' response time to in-cockpit alerts such as airspeed violations.
Design of a Cognitive Model-Based Decision Support Tool for Anesthesiology Crisis Management BIBAFull-Text 1175-1179
  N. Segall; D. B. Kaber
A decision support tool was developed for use by anesthesia providers in crisis situations. The tool alerts anesthetists to a developing crisis, manifested by changes in patient physiological variables, and provides them with a list of preventive measures for dealing with the crisis. A novel approach to the design of the tool was defined, including: (1) performing a hierarchical task analysis to identify anesthetist procedures in detecting, diagnosing and treating a critical incident; (2) carrying out a cognitive task analysis to elicit goals, decisions, and information requirements of anesthetists during crisis management procedures; (3) coding of natural language information recorded in the task analyses in a computational GOMS (goals, operators, methods, selection rules) cognitive model; and (4) prototyping an interface to present output from the cognitive model using ecological interface design principles. A preliminary validation of the tool and interface was performed with anesthesiology and usability experts.
Visualizing Operators' Cognitive Strategies in Multivariate Optimization BIBAFull-Text 1180-1184
  Sylvain Bruni; Jessica J. Marquez; Amy Brzezinski; M. L. Cummings
The proposed "Tracking Resource Allocation Cognitive Strategies" tool (TRACS) allows for post-hoc visualization of the cognitive steps exhibited by a human operator while interacting with a multivariate resource allocation decision-support interface. This tool was applied to both mission planning for multi-criteria resource allocation for military strikes, and also multi-variable geospatial path planning problems for astronaut moon traversals. Both domains involve a human operator interacting with an automated decision-support system in order to find a solution to a complex planning problem involving multivariate and constrained optimization for a cost function. With the help of TRACS, clear patterns of behavior were identified that could be correlated to performance in both applications.

HUMAN PERFORMANCE: Tool for the Human Performance Modeler' Toolkit

A Software Tool for Estimating Driver Effectiveness during Evacuations BIBAFull-Text 1185-1188
  J. French; F. Green; D. Schunk
An Evacuation Software Prediction (ESP) tool is described which allows regional managers to rapidly evaluate numerous contingencies for the evacuation of large numbers of people from an affected area and to statistically compare response strategies. This discrete event computer simulation tool is further distinguished by considering varying degrees of human emotional responsiveness to emergency evacuation, ranging from orderly calm to confused panic. The ESP tool's predicted results compared well with the observed results from rush hour traffic. A linear regression model showed that both predicted and observed sample speeds correlated well with traffic number over the samples. If the traffic flow problem presented during a typical rush hour can be used to substantiate evacuation traffic flow days or hours before a hurricane landfall, then the ESP tool may prove useful in evaluating countermeasure effectiveness for the 2006 hurricane season.

HUMAN PERFORMANCE: Putting Human Performance Modeling to the Task

Error Analysis and Threat Magnitude for Carry-On Bag Inspection BIBAFull-Text 1189-1193
  Colin G. Drury; Kimberly M. Ghylin; Karen Holness
A major part of aviation security research is prediction and improvement of systems performance to address different threat vectors. The current paper arises from the application of several ideas from the area of non-destructive inspection (NDI) to X-ray screening of carry-on baggage. The premise is that if findings from the security domain are similar to those in the NDI domain, then much prior research on inspection becomes directly applicable to security applications. Simulated threats were presented to 22 experts and 24 novices using 3 threat categories, 4 viewpoints and threats at 3 different image scales. Along with speed-accuracy trade-off, the applicability of "PoD Curve" analysis from NDI reliability was also explored along with individual differences. Results indicate support for speed-accuracy trade-off (SATO) and PoD models applied to security inspection, with large effects of expertise and smaller effects of age. Improvised explosive devices (IEDs) also produced a different pattern from guns or knives indicating that studies should include IEDs to be broadly applicable.
Flight Crew Task Reconstruction for Flight Data Analysis Program BIBAFull-Text 1194-1198
  Koji Muraoka; Hiroka Tsuda
The Japan Aerospace Exploration Agency (JAXA) has started development of a proactive flight crew operations safety analysis tool designed to be used within an air carrier's FDA (Flight Data Analysis) program. The tool reconstructs flight crew activities, both tasks which are directly detectable from an FDA dataset by changes of system parameters, and tasks which cannot be observed directly from the dataset by using an embedded rule-based human behavioral model. The model generates an estimated sequence of flight crew procedural activities as well as a workload time history. These outputs are used to assess potential problems in daily flight crew operations, such as deviations from Standard Operating Procedures (SOPs) or high workload situations, for the prevention of exceedances and incidents. As an initial step of the development, a prototype flight crew task reconstruction routine was constructed, and a numerical simulation experiment demonstrated the tool's potential capabilities.
Improving Occupant Characteristics in Performance-Based Evacuation Modeling BIBAFull-Text 1199-1203
  Rani Muhdi; Jerry Davis; Troy Blackburn
Over the past three decades, computer models have been developed to study building evacuation. Regardless of the complexity of these models, they al1 account for human characteristics such as physical movement represented by walking speeds. The current study expands previous research by introducing other human performance behaviors, which include maximum walking speed, and normal and maximum crawling speeds. Twenty-six college students participated in the study. Results indicate significant differences between normal walking speed and each of maximum walking speed, normal and maximum crawling speeds. The study also normalizes the results to walking. In addition, the study suggests that other human performance measures such as fatigue and physical exertion should be accounted for in future evacuation models.
A Quantitative Methodology for Assessment of Wheelchair Controllability BIBAFull-Text 1204-1207
  Jui-Feng Lin; Colin G. Drury; Victor Paquet
Changes in wheeled mobility user demographics and technologies over the past 30 years show the need for design guidelines for accessibility to persons with disabilities, including those who use wheelchairs. A key component is wheelchair maneuverability, which determines the clear space needed for travel in the environment. Previous studies have applied rating scales to assess the difficulty when wheelchair users maneuver in a built environment. These need to be complemented by direct maneuverability measurements. Having wheelchair users perform self-paced control tasks, for both lateral and longitudinal tasks is a potential method to meet the requirement. This study validated a methodology of measuring the steering controllability and start/stop controllability of wheelchairs so that further studies can apply this methodology to evaluate either environmental or wheelchair designs. The same speed/accuracy relationships were found for wheelchair users as had been found earlier for a variety of vehicles.
Remote Command and Control Compromises Soldiers' Trust in their Leaders BIBAFull-Text 1208-1212
  Martin Liberg; Kip Smith
We report an experiment on the effect of remote command and control on soldier performance and trust. The experiment was conducted with active duty soldiers and officers as participants at the military training camp at Kvarn, Sweden. Soldiers ran our paintball assault-lane twice, once with the officer present in the lane and once with the officer out of harm's way. Two sets of data were recorded, response times to the command to "Move!" and questionnaires on the soldier's trust in the leader. Trust was significantly greater and response times were significantly faster in the leader-present condition. The best-fit linear regression function reveals a significant negative association between the two data sets. We conclude from this result that (1) remote command and control is associated with a decrement in soldiers' trust in their leader and that (2) this decrement in trust is associated with compromised soldier performance.

INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences in Cognitive Performance

Expert Performance in Law Enforcement: Are Skilled Performers More Effectively Constraining the Situation to Resolve Representative Dynamic Tasks than Novices BIBAFull-Text 1213-1217
  Lauren Tashman; Kevin R. Harris; Jason Ramrattan; Paul Ward; David W. Eccles; K. Anders Ericsson; A. Mark Williams; David Rodrick; Laura Hassler Lang
Ericsson and Kintsch (1995) suggested that long-term working memory (LTWM) allows skilled performers to predict the occurrence and consequence of future events and anticipate future retrieval demands. Traditional domains of expertise, such as typing and text comprehension, have been used to provide evidence for mechanisms that permit such behaviors. Real-world tasks are more dynamic and challenging, particularly when performed under time-pressure. We examined skilled and less-skilled law enforcement officers in a simulated task environment. Performance measures (e.g., un-holstering, aiming, and firing a weapon) were used to test LTWM theory and participants' comprehension of the situation by assessing the consistency between actions currently being performed and the situation outcome. These data provided evidence that skilled officers make predictive inferences, anticipate future events, and rely upon information beyond that which is available in the current scenario.
Familiarity and Expertise in the Recognition of Vehicles from an Unmanned Ground Vehicle BIBAFull-Text 1218-1222
  Thomas D. Fincannon; Michael Curtis; Florian Jentsch
The purpose of this study was to examine the role of familiarity and expertise in remote perception from unmanned ground vehicles (UGVs). Fifty-two volunteers, of whom 23 were Army ROTC cadets, participated. They were first asked to identify vehicles on a written test, and scores from the test were used to predict the amount of information reported from a video recording, captured from a UGV camera, in a scaled MOUT facility. ROTC cadets are compared with the general subject pool in order to explore differences between civilian and military vehicle recognition. Results from a written vehicle recognition test indicate that all participants were most familiar with civilian vehicles and ROTC cadets were more familiar with military vehicles than the general population. Regression analyses revealed that both ROTC experience and vehicle familiarity were predictive of the amount of information correctly reported from the UGV camera video. We believe that training for expertise and motivation should be considered for future research.
Individual Differences in Working Memory, Sense of Direction, and Route-Learning BIBAFull-Text 1223-1226
  Ian Reagan; Carryl L. Baldwin
The current experiment examined the role of working memory components during route-learning as a function of Sense of Direction. Individuals with good or poor sense of direction (GSD/PSD) were selected a priori. Participants learned routes while performing working memory tasks consisting of spatial interference (SI) or verbal interference (VI). Previous empirical research indicates that GSDs rely on visual-spatial strategies while PSDs rely on verbal strategies for navigation. Based on Baddeley's (1992) working memory model we therefore expected route learning performance to be differentially disrupted by SI in GSDs and VI in PSDs. Providing partial support for our prediction, GSDs took more time and made more errors in routes learned during SI relative to VI, and PSDs were slower when traversing routes learned under VI relative to SI. Our findings show strong individual differences in route-learning performance and provide support for tailoring navigation systems and training programs to reflect these differences.
Strategic Differences in Mental Rotation Tasks Based on Gaze Durations BIBAFull-Text 1227-1230
  Shan Bao; Linda Ng Boyle
The objective of this study is to investigate whether strategy differences in mental rotation performance can be explained using gaze durations collected from an eye tracker. To investigate this, 36 participants were administered an electronic version of the Purdue Spatial Visual Test: Rotation. Three questions (out of 30) were selected based on the overall response accuracy to represent an easy, moderately difficult, and difficult question. Participants were then segmented into two groups (high accuracy and low accuracy) based on test scores. Significant interaction effects between the groups and the five possible choices were observed for the gaze durations of each question (easy: F(4,170) = 9.05, p < 0.0001; moderately difficult: F(4,170) = 41.12, p < 0.0001; difficult: F(4,170) = 2.89, p< 0.05). The gaze durations of the high accuracy group were primarily skewed towards one of the five potential response choices suggesting a holistic approach. For the low accuracy group, an analytic approach appears likely with gaze durations more evenly distributed across all choices.
Computer Based Training and Multimedia Design: The Role of Spatial Aptitudes in Learning BIBAFull-Text 1231-1235
  Sandro Scielzo; Stephen M. Fiore; Yaela Dahan; Joseph Lopez; Shawn Stafford
The present study manipulated both the technology (Microsoft PowerPoint versus Macromedia Director) and the design (Text Priming versus No Text Priming) in a computed-based training multimedia environment. The study investigated trainees' spatial aptitude and how it interacted with computer-based training design. The specific computer-based training environment employed in this experiment was based on presenting the principles of flight to naïve participants. A multifaceted knowledge test was developed to assess different levels of knowledge integration. Overall, results suggest that technology type did not play an important role in knowledge acquisition. Priming type also did not show significant effects; however, when factoring trainees' spatial ability, significant aptitude-treatment interactions emerged. We discuss these findings as they relate to computer-based training multimedia paradigms.

INDIVIDUAL DIFFERENCES IN PERFORMANCE: Diversity of Individual Differences Factors Predicting Performance

Diversity of Factors that are the Best Predictors of Individual Performance BIBAFull-Text 1236-1239
  Krystyna Gielo-Perczak; Waldemar Karwowski; Shrawan Kumar; Colin Drury; Moshe Solomonow
A goal of this session is to generate an environment that promotes the exchange of ideas between biomechanics, cognitive engineering and performance as an integration of the individual differences within human capabilities. The identification of the source of the individual differences in performance through different approaches will be presented.
   The discussion begins with a question why recognizing individual differences in human capabilities and limitations is necessary. Then the discussion turns to biomechanical predictors of human strength performance. The first predictor will be related to the muscles and their EMG responses as the effect of individual differences. The second and third predictor of human physical strength will be the bone geometries and ligaments. All occupational activities are carried out within some psychosocial environment. The last panelist will draw attention to the data set of variables, characterizing individual differences in performance taking into account personality, visual and cognitive performance, and training.

INDIVIDUAL DIFFERENCES IN PERFORMANCE: Individual Differences Potpourri

Cognitive Slips-Failures and Daily Stress: Further Investigations with the Short Stress State Questionnaire - Daily (SSSQ-D) BIBAFull-Text 1240-1244
  William S. Helton; Richard Holmstrom
This article presents a study providing further psychometric and validation evidence of a short multidimensional self-report measure of daily stress state, the Short Stress State Questionnaire -Daily (SSSQ-D; Helton, Fields, & Thoreson, 2005). Forty-three participants filled out the SSSQ-D twice daily for approximately 23 days, once in the morning and once at night. They also reported daily cognitive slips-failures. Chain-P Factor Analyses of the individual items for both pre- and post-assessments were conducted and the relationships between the SSSQ-D factors and daily self-reported cognitive slips-failures were examined both within and between participants. The factor analyses, as previously indicated by Helton, Fields, and Thoreson (2005), differentiated three aspects of subjective stress: Task Engagement, Distress, and Worry. Daily Distress and Worry correlated moderately with cognitive slips, both within and between individuals. The 24-item SSSQ-D appears to be a reliable measure of daily stress state, potentially useful in naturalistic studies.
The Role of Individual Differences in Confidence and Response Bias BIBAFull-Text 1245-1248
  Do Hyung Kim; Kyung Soo Lee; Kyeong Tae Kim; Su Ran Lee; Hye Bin Rim; Ji Seon Shin; Young Woo Sohn
This research examined how individual differences in personality traits are related with confidence and response bias for situation awareness. Participants completed the big-five personality inventory, the Need for Closure scale inventory, and the unsafe attitude questionnaire followed by a flight situation awareness task designed to assess confidence level and response bias. The data obtained were then analyzed using the framework of Calibration and Signal Detection Theory. The results suggest that extraversion and emotional stability are positively correlated with overconfidence. In addition, extraversion, conscientiousness, and intellect are negatively correlated with response criteria. This suggests that those with lower levels of extraversion, conscientiousness, and intellect are likely to use more conservative response criteria. Our findings have a practical implication that student pilots' personality factors should be considered for effective pilot training.
Learning to Discriminate Terrorists: The Effects of Emotional Intelligence and Emotive Cues BIBAFull-Text 1249-1253
  Angela N. Fellner; Gerald Matthews; Joel S. Warm; Moshe Zeidner; Richard D. Roberts
Emotional intelligence (EI) is the presumed ability to successfully understand and manage emotion. El may affect the ability of security personnel to gauge the relevance of emotional cues in determining whether a suspect is a terrorist. 180 participants decided whether "virtual reality" animated characters were to be designated as terrorists, in a discrimination-learning paradigm. Three types of identifying cue (positive or negative facial emotion, and an emotion-neutral cue) were manipulated, and the number of errors was recorded, over 100 trials. EI, personality, and general cognitive ability were assessed pre-task. Subjective state was assessed pre- and post-task. Results showed faster learning with emotive cues. EI and personality failed to predict performance; but EI predicted subjective state, which predicted rate of learning with emotive cues. Practical techniques for support of security personnel should focus on how subjective states may impact attention to potentially relevant cues to the status of a suspect.
Cerebral Blood Flow Velocity and Task Engagement as Predictors of Vigilance Performance BIBAFull-Text 1254-1258
  Lauren E. Reinerman; Gerald Matthews; Joel S. Warm; Lisa K. Langheim; Kelley Parsons; Christina A. Proctor; Tazeen Siraj; Lloyd D. Tripp; Robert M. Stutz
Responses to a brief six-min screening battery involving high-workload tracking, verbal working memory, and line discrimination tasks were used to predict subsequent performance on a 36-min vigilance task. Two predictors of interest were subjective state, as indexed by the Dundee Stress State Questionnaire (DSSQ), and cerebral blood flow velocity (CBFV), measured via transcranial Doppler sonography. The results testify to the importance of assessing task-induced responses for predicting vigilance performance. They also indicate that forecasting vigilance performance is a complex endeavor requiring a set of multidimensional predictors. Specifically, higher post-battery task engagement scores on the DSSQ in this study and higher levels of CBFV in the left hemisphere during performance of the screening battery predicted more correct detections on the subsequent vigilance task. These findings are interpreted in the light of the resource-workload model of vigilance, and their practical significance is discussed.
Evaluating Preferences for Mobile Phone Features BIBAFull-Text 1259-1263
  Naomi F. Glasscock; Michael S. Wogalter
Mobile (or cellular) phone usage has grown substantially over recent years. Products continue to become smaller while the number of features that they contain increases. Recently, manufacturers have begun to market products toward specific demographic groups, like children or older adults. However, there is relatively little research concerning individual differences in feature preferences, particularly with respect to age. The present research explores self-reported preferences for 24 mobile phone features. Participants (N = 194) rated each feature on a scale indicating their likelihood to use the feature if it was available in their mobile phone. Mean ratings indicated that Phonebook, Voicemail, Caller ID, and Call History were the features individuals reported most likely to be used. Approximately half of the features had mean ratings that indicated that they were not likely to be used. Pearson correlation coefficients between age and feature ratings resulted in 18 (out of 24) negative and significant correlations, indicating that most features are reportedly less likely to be used with increasing age. This notion was further confirmed by a positive correlation between age and the number of features rated as unlikely to be used. Analysis of variance also revealed effects of gender, age category, student status, and parental status on preference ratings. Implications for the design of mobile phones for different users are discussed.

INDUSTRIAL ERGONOMICS: The Promise and Limitations of Ergonomics

The Role of Ergonomics in Preventing and Reducing the Burden of Musculoskeletal Conditions BIBAFull-Text 1264-1266
  Barbara Silverstein
Five important developments this decade can clarify and promote the role of ergonomics in preventing and reducing the burden of musculoskeletal disorders: 1) worldwide acceptance of this decade as the bone and joint decade, 2) changing demographics and 3) change in worker-workplace relationships, 4) research advancements in the laboratory and in the workplace including prospective studies, 5) publication of revised ISO 6385 (2004) [1].
Beyond Ergonomics: Evolving to Achieve Fewer Back Injuries in the Future BIBAFull-Text 1267-1269
  Stuart M. McGill
Painful, disabled backs from tissue damage do not just happen, nor are they caused by psychosocial issues. Nearly all injury mechanisms are linked to joint motion and posture patterns. For example, posture determines which tissue is damaged and at which load (magnitude, duration, frequency, load rate etc). In the case of disc hemiation, repeated joint flexion appears to be a necessary condition. Even with an "ergonomically correct" or well designed job, some will still experience pain or injury. This is because so much of the loading experienced by joints is generated not by external loads, but by the muscles themselves. People use different strategies to activate muscles and move through motion patterns. Thus, the way that they choose to move plays a large role in determining their risk of injury. While Ergonomics is important, it is only a component in a broader effort needed to achieve minimal injury rates. In many cases, ergonomic approaches involving job design are impractical or do not address the injury mechanisms that form the root cause of disabled backs. Entire sectors of the workforce cannot use job design (such as law enforcement, forestry, farming, fishing, to name a few). Evidence suggests that an approach to address the cause rather than the symptoms must look beyond ergonomics and consider changing the individual. Successful reduction of back injury rates in the future will have to consider "changing the person to fit the task".

INDUSTRIAL ERGONOMICS: Postural Influences on Low Back Biomechanics

Sagittal Plane Moment Arms of the Male Lumbar Region Rectus Abdominis: Upright vs. Supine Posture BIBAFull-Text 1270-1273
  Michael J. Jorgensen; Francis W. Smith
Prior studies of torso muscle moment arms for inputs into torso biomechanical models have been derived from subjects lying supine. Recent research suggests that moment arms of the rectus abdominis increase when standing versus lying supine. The objective of this study was to quantify and compare the sagittal plane rectus abdominis moment arm from upright and supine postures. Cross-sectional MRI images from ten males in both upright and supine postures were obtained. Digitizing software was utilized to quantify the sagittal plane moment arms of the rectus abdominis muscle. The mean sagittal plane moment arms were significantly larger at each lumbar intervertebral level in the erect posture compared to the supine posture, ranging from 15.9% larger at L1/L2 to 49.3% larger at L4/L5. These findings indicate that the torso internal moment generating capability would be represented differently in biomechanical models that use data from studies where subjects were upright versus supine.
Non-Invasive Evaluation of the Effect of Stooped Posture on Spinal Intervertebral Discs Using MRI BIBAFull-Text 1274-1278
  David A. Reiter; Fadi A. Fathallah; Jeffrey H. Walton
Due to a need of more descriptive exposure assessment of stooped work as it pertains to low back pain and low back disorders, a new evaluation tool has been developed for non-invasive evaluation of the spinal intervertebral disc. This evaluation tool uses magnetic resonance imaging (MRI) in combination with custom analysis software to measure deformation and compare spatial changes in quantitative MR information (i.e., proton density and relaxation constant T2) in intervertebral discs in response to various long duration load exposures. In vitro loading was performed on porcine cervical spine segments to simulate prolonged stooped posture and erect posture. The image analysis tool provides a means of quantitatively comparing the tissue response of these two different loading conditions. The results suggest prolonged stooped posture has a noticeable impact on disc height and disc hydration compared to static erect posture. The results also provide compelling support for the use of such an approach in evaluation of short and long term load exposures in vivo as they influence mechanical and biochemical health of the intervertebral disc.
Prediction of Lumbar Motion Segment Angles Using Trunk Angle and Antrhopometry BIBAFull-Text 1279-1283
  Riley E. Splittstoesser
To develop a simple method for dynamically assessing lumbar motion segment angles that accounts for individual variability and remains inexpensive to apply.
   Background: Current biomechanical models do not dynamically assess motion segment angles. This results in inaccurate separation of overall spinal load into shear and compression.
   Methods: Twenty-nine males performed sagittally symmetric exertions. Anthropometry and sensor data were input into a geometric model to compute L5/S1 through T12/L1 motion segments angles. Linear regression equations were developed using anthropometry and trunk angle. These equations were applied to an independent set of four subjects with known angles. The trunk angle used here was compared to a commonly used trunk angle measure for widespread usability.
   Results: The L5/S1 through L2/L3 models are predictive of motion segment angles.
   Conclusions: Motion segment models developed here require simple, inexpensive measurements of torso angle and anthropometry. They are easy to use and applicable in clinical, research and industrial situations.
The Effects of a Stooped Work Task on the Muscle Activity and Kinematics of the Lower Back BIBAFull-Text 1284-1288
  Brandon J. Miller; Fadi A. Fathallah
Working in a stooped posture is an important risk factor for low back disorders (LBDs) that requires special focus. Spinal flexion increases the loading on the passive tissues of the lumbar spine compared to neutral postures, yet sustained or repeated flexion reduces the load bearing capability of these tissues. The objective of this study is to assess the effect of performing a stooped work task on the passive tissues of the low back. Passive tissue response is assessed by measuring trunk sagittal range of motion and the occurrence of the flexion-relaxation (F-R) phenomenon at specific times during the work period. Fourteen subjects (10 female and 4 male) were instrumented with a portable data collection system while performing the stooped work task of fresh-market tomato harvest for one hour in the morning and one hour in the afternoon. Results indicate significant changes in the trunk and lumbar sagittal range of motion and F-R after only 11 minutes of stooped work, with few changes for durations up to 55 minutes of work. The potential benefits of short, frequent rest breaks on recovery of passive tissue response are also demonstrated. The data collection device developed for this study allows for further investigation of the effects of stooped work on the lower back, which could lead to improved interventions to reduce LBD risk.
Development and Evaluation of Ergonomic Interventions for Bucket Handling on Farms BIBAFull-Text 1289-1293
  Steven C. Tang; Fadi A. Fathallah
Recent studies have shown that many of the activities children and adolescents perform on farms are associated with increased LBD risks, particularly, the handling of water and feed buckets. Hence, the purpose of this study is to introduce and evaluate two interventions, Ergo Bucket Carrier (EBC) and Easy Lift (EL), for youths (and adults) to handle water/feed bucket on farms. Nine subjects (six males and three females) consented to participate in this study. To assess the risk of LBD, the participants were instrumented with a three-dimensional spinal electrogoniometer while handling water buckets using three handling methods. The results showed that the two interventions can effectively and significantly decrease the magnitudes of the overall LBD risk in many of the tasks evaluated. Particularly, EBC effectively reduce the LBD risks for carrying and dumping tasks and so does EL for lifting tasks. Results of the subjective response were consistent with the objective evaluations. This study demonstrated the potential for ergonomic interventions in reducing LBD risks during the common farming and industrial task of bucket handling.
Trunk Stability in Dynamic Movement BIBAFull-Text 1294-1298
  Kevin Granata; Scott England
Spinal stability has been characterized in static but not in dynamic movements. The goal of this study was to determine whether movement pace and direction of dynamic trunk flexion influence the control of spinal stability. Twenty healthy subjects performed dynamic lifting movements at 20 and 40 cycles per minute. Lyapunov exponents were calculated from the measured trunk kinematics to estimate stability. Complexity of torso dynamics required at least five embedded dimensions thereby indicating that torso dynamics requires more than the 3-dimensions of movement for sufficient characterization. Dynamic stability is was greater in slow lifting movement than in fast movements. Asymmetric movements demonstrated greater multi-dimensional kinematic divergence than asymmetric movements. This indicates that the sagittal plane of movement may not be a principle dynamic axis of torso movement. Results provide biomechanical insight regarding the role of workplace design and risk of musculoskeletal instability in dynamic lifting tasks.

INDUSTRIAL ERGONOMICS: Prevention of Work-Related Musculoskeletal Injuries

Prevention of Work-Related Musculoskeletal Disorders BIBAFull-Text 1299-1302
  Sue Ferguson; Barbara Silverstein; Martin Cherniack; Arun Garg; Steve Lavender
This panel is discussing research conducted as part of the Work-Related Musculoskeletal Disorder Consortium with the National Institute of Occupational Safety and Health. The panel has two researchers conducting low back research and two researchers performing upper extremity research. The goal of the panel is to inform the audience about the consortium and some of the state of the art research that is being conducted.

INDUSTRIAL ERGONOMICS: The Neck and Upper Extremity

Effects of Pace and Work Stress on Upper-Extremity Kinematic Responses in Sign Language Interpreters BIBAFull-Text 1303-1307
  Jin Qin; Matthew Marshall; Jacqueline Mozrall; Marc Marschark
Sign language interpreting is an occupation that suffers from high levels of repetitive motion injuries (RMIs) and burnout due to the high physical and cognitive demands of the interpreting task. The objective of this research was to determine the effects of work pace and psychosocial stress on the wrist kinematics of sign language interpreting. It was found that neither pace nor stress affected mean wrist position, but increased pace resulted in a significant increase of both mean velocity and acceleration, with increases ranging from 10.7-18.6%. Increased psychosocial stress resulted in a significant increase of left-hand (non-dominant) mean velocity and acceleration, with increases ranging from 14.8-19.5%. No effect of stress was observed for the right hand. In addition, several wrist kinematic variables of interpreting exceeded previously established high risk industrial benchmarks. The results of this work support earlier research which found deleterious effects of work stress on the biomechanical responses of the lower back.
An Investigation of Complaints of Shoulder Pain and Discomfort from Library Workers and the Redesign of a Circulation Desk BIBAFull-Text 1308-1312
  John L. Wick; Susanne Woodford
Checking out books and other media for library patrons is a typical job in most libraries. The checkout job is done at King County Library System by Library Assistants at a circulation desk. Some Library Assistants experienced shoulder pain or discomfort. Ergonomics evaluations were performed to determine the ergonomics risk factors in the checkout job that could contribute to stress to the shoulders. The ergonomics evaluations identified ergonomics risk factors that could cause shoulder pain or discomfort that were directly related to the circulation desk design. The results of the ergonomics evaluations were used to develop a new circulation desk design. The new design successfully addressed the problems identified in the original circulation desks, created a more efficient workstation compatible with the tasks involved in checking out books for the patrons, and reduced the probability of shoulder injury. This paper describes the findings of the ergonomics evaluations and the results of the changes in the new circulation desk design.
Efficacy of Using Thermography to Assess Shoulder Loads During Overhead Intermittent Work BIBAFull-Text 1313-1317
  Linsey M. Barker; Laura E. Hughes; Kari L. Babski-Reeves
Upper extremity work related musculoskeletal disorders remain a priority research area due to their prevalence and cost despite efforts to mitigate their presence in the workplace. A laboratory study was conducted to investigate the effects of task parameters on surface temperature patterns, which have been previously linked to musculoskeletal injury, of the middle deltoid and trapezius while performing overhead tasks. Twelve participants (6 males and 6 females) completed one hour test sessions of an automotive assembly task simulation. Independent variables included duty cycle (33%, 50%, and 67%) and work height (two overhead positions). Results showed that thermography readings are sensitive to task demands on the musculature during dynamic tasks. Duty cycle and the interaction of duty cycle and work height were found to affect temporal and spatial thermal patterns, with lower duty cycles and lower work heights resulting in higher temperatures and faster rates of change.
Developing a Non-Human Primate Experimental Model for Studying Carpal Tunnel Syndrome BIBAFull-Text 1318-1322
  Carolyn M. Sommerich; Steven A. Lavender; John A. Buford; Jacob Banks; Sahika Vatan Korkmaz; William S. Pease; Stephanie Moran
This study investigated changes in median nerve conduction velocity (NCV) over several weeks of exposure to a voluntary, moderately forceful, repetitive pinching task performed for food rewards by a small sample of young adult female monkeys (Macaca fascicularis). Sensory NCV, derived from peak latency, decreased significantly in the working hands of three of the four subjects. The overall decline in NCV was 25-31% from baseline. There was no decrease in NCV in the non-working hands. The results demonstrate a temporally unambiguous relationship between exposure to a moderately forceful, repetitive manual task and development of median mononeuropathy. This study contributes to the pattern of evidence of a causal relationship between manual work and significant median nerve impairment (carpal tunnel syndrome in humans). In the future, such a model could be used to assess dose-response relationships between physical risk factors and carpal tunnel syndrome.
A Randomized Controlled Trial Evaluating the Effect of Two Task Chair Designs on Shoulder and Neck Pain Among Sewing Operators BIBAFull-Text 1323-1326
  David M. Rempel; Pin-Chieh Wang; Ira Janowitz; Robert J. Harrison; Fei Yu; Beate R. Ritz
This 4 month randomized controlled trail evaluated the effect of chair design on neck/shoulder pain among sewing machine operators. 277 sewing machine operators with neck/shoulder pain were assigned to receive (1) miscellaneous items (control group), (2) a chair with a flat seat pan plus miscellaneous items, or (3) a chair with a curved seat pan plus miscellaneous items. Participants who received the flat seat chair experienced a decline in pain of 0.14 (95% CI: 0.07 to 0.22) points per month compared to those in the control group, while those who received the curved seat experienced a decline of 0.34 (95% CI: 0.28 to 0.41) points per month compared to those in the control group. These findings demonstrate that an adjustable height task chair with a curved seat pan can reduce neck and shoulder pain severity among sewing machine operators.

INDUSTRIAL ERGONOMICS: Slips, Trips, and Falls

Midfoot Shape When Standing on Soft and Hard Footbeds BIBAFull-Text 1327-1331
  Ravindra S. Goonetilleke; Channa P. Witana
In this study, the plantar shape of the midfoot was determined when the participants were standing on three different surfaces. Foot impression castings of sixteen participants were made when they were standing on a custom-made device. These castings were laser scanned in order to quantify the shape differences. The results showed that, when the amount of cushioning on the support surface was changed, the plantar mid-foot sag changed by 5.0 mm. The results have important implications for footwear design as midfoot shapes in footwear are somewhat standardized and are not adjusted to account for the cushioning properties of the footbed. The mismatched deformations between feet and shoes as a result of design, structure and material used in the heel and forefoot regions of shoes can contribute to unwanted strain on the plantar fascia of the human foot.
Gait Asymmetry: Factors Influencing Slip Severity and Tendency among Older adults BIBAFull-Text 1332-1335
  Sukwon Kim; Thurmon Lockhart
Research on the relationship between gait asymmetry and the likelihood of slips are not clear, especially, for older adults. The present study evaluated the gait asymmetry among older adults and, further, evaluated effects of gait asymmetry on the likelihood of slips. Eighteen older adults (65 and older) participated in the study. HCV, horizontal force, and RCOF measured at non-dominant leg during heel contact phase of gait cycle were significantly higher than those at dominant leg. The results indicated that the likelihood of slips could increase when transitioning the whole body center-of-mass with left leg contacted on the ground while right leg was in swing phase. The results indicated that gait asymmetry or limb dominance could contribute to increasing the likelihood of slips.
Reliability of Cop-Based Postural Sway Measures BIBAFull-Text 1336-1340
  Dingding Lin; Hyang Seol; Maury A. Nussbaum; Michael L. Madigan
Measures of human sway during upright standing are frequently used as indirect measures of the postural control system. The objective of this study was to assess the reliability of several center-of-pressure-based sway measures. Test-retest reliability was determined both within-days (under different visual and surface conditions) and between-days (5 different days). Intraclass Correlation Coefficient (ICC), Standard Error of Measurement (SEM), Minimal Metrically Detectable Change (MMDC), and Coefficient of Variation (CV) were used as reliability indices. Mean velocity was found to be the most reliable measure among those evaluated. Overall, between-day reliability indices were better than within-day reliability. When subjects were standing on a compliant surface, several measures exhibited better reliability under 'eyes open' condition. These results can be useful in guiding the selection of postural sway measures and appropriate number of replications to improve sway assessment.
Aging Effect on Initial Postural Responses of Unperturbed Foot to Unexpected Slips BIBAFull-Text 1341-1345
  Jian Liu; Thurmon E. Lockhart
Consideration of every aspects of body motion that may contribute to balance recovery after unexpected slips is regarded to be fundamental for thorough understanding of slips and falls mechanism. The objective of current study was to assess the aging effect on the initial postural responses of the unperturbed foot after slip initiation. Totally 20 young and 23 old adults participated in a laboratory study, in which slippery surface was induced without their awareness. Unperturbed foot reaction time, contact velocity, and initial BoS (base of support) were quantified kinematically from motion analysis data after slip start. Apparent toe-touch strategy by unperturbed foot was found to be employed by most individuals. Initial contact dynamics was not found to be affected by either aging or slip outcome. The fact that all the individuals without using toe-touch strategy fell demonstrated the clear importance of unperturbed foot responses to avoid fall accidents.
Accommodating Slips and Falls Hazards Using Anticipatory Locomotor Adjustments BIBAFull-Text 1346-1350
  Angela DiDomenico
Successful hazard accommodation is an important aspect of maintaining a continuous walking pattern and avoiding slips and falls. Kinematic data was collected for thirty-six participants who were asked to step on a target within a linear runway. Experimental conditions were varied to produce a range of anticipatory locomotor adjustments by using two walking velocities (normal, fast) and target sizes (5cm x 5cm, 33cm x 53cm). Gait parameters were examined for the five steps prior to hitting the target. Repeated measures ANOVA was performed to determine the changes in the gait parameters among the steps. Results showed a distribution of anticipatory locomotor adjustments over multiple steps, with the largest adjustments generally occurring during the last step. Given ample time to perceive a hazard and make necessary adjustments, it seems that individuals can successfully accommodate a slip and fall hazard. Present findings indicate that future research regarding slips and falls hazards may benefit from including analyses of multiple steps preceding hazards to understand the entire event.

INDUSTRIAL ERGONOMICS: Ergonomics of Computer Use

Measuring Computer Style: The Frequency and Distribution of Computer Keyboard Behaviors BIBAFull-Text 1351-1355
  Nancy A. Baker; Mark S. Redfern
Although computer use is a risk factor for musculoskeletal disorders, there is currently no valid and reliable method to measure computer keyboarding style in the workplace. This paper provides the frequencies and distribution of items of the Keyboard Personal Computer Style instrument (K-PeCS), a 20 item criterion-based observational instrument that can be used in the workplace to document computer keyboard workstyle. The K-PeCS was used to rate the computer keyboarding style of 21 computer users in their workplace. The resulting frequency and distribution suggest that the K-PeCS documents a variety of postures and behaviors that occur during computer keyboarding tasks, and that the criterion selected are reasonably well-distributed amongst this sample of computer keyboard users. The K-PeCS, therefore, is adequately capturing the varied aspects of computer keyboarding style.
Gender Differences in the Relationship Between Daily Computer Usage and Musculoskeletal Symptoms Among Undergraduate Students BIBAFull-Text 1356-1360
  Che-hsu (Joe) Chang
We conducted a repeated measures pilot field study on 27 undergraduate students (14 males and 13 females) to investigate the relationship between daily computer usage time and musculoskeletal symptoms. For three one-week periods during a single semester, students reported symptoms (outcome) 3-5 times daily while computer usage time (exposure) was objectively measured by a usage monitor software installed onto participants' own computer. Generalized estimating equation (GEE) regression models tested the relationship between outcome and exposure. In males, each additional hour of daily computer usage was associated with an increased odds ratio of reporting symptoms to 1.18 (1.05-1.34). In females, the corresponding increased odd ratio for each additional hour of daily usage was 1.02 (0.96 to 1.08). The results also suggested a potential dose-response relationship between daily computer usage time and musculoskeletal symptoms; however, the significance of relationship was different between genders.
Prevalence of Lifted Finger Behavior and Postures During Two-Button Computer Mouse Use BIBAFull-Text 1361-1365
  David L. Lee
Two-button computer mouse users may exhibit sustained lifted finger behaviors to prevent inadvertent activations by avoiding finger pressure on the buttons, leading to prolonged finger extensor muscle loading. One hundred graduate students were observed during normal computer work in a university computer facility to qualify and quantify the prevalence of lifted finger behaviors and extended finger postures, as well as wrist/forearm support, during specific mouse activities. The highest prevalences observed were 48% of the students lifted their middle finger during mouse drag activities, and 23% extended their middle finger while moving the mouse. In addition, 98% of the students rested their wrist and forearm (77%) or wrist only (21%) on the workstation surface. These findings indicate that two-button mouse users do lift and hold their fingers during computer work, while supporting their wrist/forearms. Potential applications include ergonomic design strategies to reduce exposure to risk factors that may contribute to hand/forearm musculoskeletal pain.
The Effect of Six Keyboard Designs on Wrist and Forearm Postures BIBAFull-Text 1366-1369
  Alan Barr; David Rempel; Ed Young; David Brafman
There is increasing evidence that alternative geometry keyboards may prevent or reduce arm pain or disorders and presumably the mechanism is by reducing awkward arm postures. However, the effects of alternative keyboards, especially the new designs, on wrist and arm postures are not well known. In this laboratory study, the wrist and forearm postures of 100 subjects were measured with a motion analysis system while they typed on 6 different keyboard configurations. There were significant differences in wrist extension, ulnar deviation, and forearm pronation between keyboards. When considering all 6 wrist and forearm postures together, the keyboard with an opening angle of 12°, a gable angle of 14°, and a slope of 0° appears to provide the most neutral posture among the keyboards tested in the configuration tested. This study identifies significant wrist and forearm posture differences between 6 keyboard configurations. These findings may assist in ergonomic recommendations regarding computer usage.

INDUSTRIAL ERGONOMICS: Workplace Design Issues

Musculoskeletal Stress on Miners Performing Roof Screening Operations BIBAFull-Text 1370-1374
  Susan Kotowski; Sean Gallagher; Kermit Davis; Kelly Baron; Craig Compton
Roof screen is often bolted to the mine ceiling to help control hazardous rock falls in coal mines. While the screen prevents rock fall injuries, its installation may expose the miner to musculoskeletal stress. The purpose of this study was to evaluate methods of handling roof screen. Subjects performed installation tasks under a normal and intervention condition while trunk kinematics and muscle activity data were collected. Trunk kinematics were not affected by the intervention but were significantly higher in the morning than in the afternoon. Muscle activity did not differ significantly with seam height but was significantly reduced by the intervention. Overall, this study showed that musculoskeletal stressors during screen installation were reduced by the proposed intervention.
The Impact of Work Scheduling on Injury Risk BIBAFull-Text 1375-1379
  George E. Brogmus
The way work is scheduled can have a significant impact on productivity and safety. Trying to determine a reliable relationship between scheduling details and this impact has not been easy. The relationship is a complex one because it is not simply a mater of how many hours a person is working, but also includes when the person is working (daytime, afternoon, night), how many "days" (shifts) in a row the person is working, and how frequently during the work day the person takes breaks from work. Recent research has pointed out that there are sufficient good-quality studies to model the impact of these factors on injury risk. The available research was reviewed and developed into a model that allows estimation of the relative risk based on type of shift (day, afternoon, night), number of consecutive shifts, hours per shift, and time between breaks. This paper describes the source research data, modeling procedures and cautions of interpreting and applying the modeling.
Three-Dimensional Variability of Static Anthropometric Dimensions: Considering Anatomy, Behavior and Process BIBAFull-Text 1380-1383
  David J. Feathers; Victor L. Paquet
Capturing anatomical landmarks using an electromechanical measurement system shares facets of traditional anthropometry (palpation/haptic inspection, visual inspection). Electromechanical measurement systems, however, capture discrete anatomical landmarks used to create multiple anthropometric dimensions. This study investigated measurer variation for the multi-modal task of capturing static, three-dimensional landmarks. Two trained measurers used an electromechanical system to repeatedly render five upper extremity landmarks on a healthy adult, braced in a static position. ANOVA showed significant differences across measurers (p < 0.01) in each coordinate axis (X, Y, Z) for three landmarks. Post-hoc dimensioning of Bi-Humeral Epicondylar breadth and Radiale-Radial Styloid length utilized these landmark data as endpoints in linear dimensions. ANOVA showed significant results for measurer for Bi-Humeral Epicondylar breadth (p < 0.01). This study details measurer variation for the task of rendering three-dimensional landmarks and the impact this variation has on the creation of linear dimensions. Studying the landmark digitization variation will aid in the reduction of linear dimension variation, enable effective training, and help mitigate the impact of differential search strategies used to capture digitized landmarks in three-dimensions.
An Approach for Evaluating 3-D Workspace Using Photogrammetry and Cad Software BIBAFull-Text 1384-1387
  Ji Hong Chang; Fadi A. Fathallah
Evaluation of workspace layout and design is a common task among ergonomists. It is desirable to find accurate and expedient means to generate the workspace in a virtual form, which allows the evaluation of various aspects of the human-workspace interface. The purpose of this practice-based paper is to introduce and evaluate a method, known as photogrammetry, which facilitates the recreation of workspaces in virtual three-dimensional (3-D) space. To demonstrate the utility and accuracy of this approach, a photogrammetry software was used to generate virtual 3-D models of ten popular agricultural tractors. Accuracy evaluation showed that photogrammetry is generally more useful for larger and more complicated objects, while smaller and simpler objects tend to yield less error. Furthermore, the paper shows examples on how these virtual 3-D mockups can be incorporated into Computer Aided Design (CAD) or ergonomic software in order to evaluate operator-cab interface issues such as reach, clearance and field of vision. This two-layered approach can be a very useful and powerful tool for ergonomists when designing and evaluating various human-workspace interfaces.

INDUSTRIAL ERGONOMICS: Evaluation of Industrial Tasks

Interaction Between Trunk and Wrist Kinetics and Kinematics During a Simulated Pruning Task BIBAFull-Text 1388-1392
  John C. Kung; Fadi A. Fathallah
Winegrape vine pruning require repetitive gripping and awkward body postures. The purpose of this study is to examine the effects of cutting height and forearm posture on trunk and wrist posture, force production, and muscle activities during simulated vine pruning. Ten healthy subjects (3 female and 7 male) participated in the study. Subjects cut dowels simulating shoots with pruning shears at 5 cutting heights tailored to subject anthropometry at three forearm postures. Trunk and wrist kinematics, force exertion, and forearm EMG were monitored. The results showed significant change in force exertion; and trunk and wrist kinematics in stature and knee cutting heights. The information from this study could assist in ergonomic trellis design, injury prevention, and manual labor work guidelines.
Differences Between Male and Female Psychophysically Determined Maximum Acceptable Forces of a Cart Pushing Tasks BIBAFull-Text 1393-1396
  Vincent M. Ciriello
The purpose of this experiment was to compare the differences in maximum acceptable initial and sustained forces between males and females while performing a 7.6 m pushing task at a frequency of 1 min-1 on a high-inertia pushcart and to compare those differences with the gender differences of our criterion magnetic particle brake treadmill push task (Snook and Ciriello, 1991). Eleven female and eight male industrial workers performed two 2- hour pushcart tasks in the context of a larger experiment. The results revealed that maximum acceptable initial and sustained forces of pushing for women on the pushcart were 67% and 69% of the initial and sustained forces for men, comparable to our magnetic particle brake treadmill push task data. These findings may indicate that adjustments to our pushing data may not be necessary if replication of this experiment yields similar results.
The Effects of Scaling Height and Scaling Bar Design on Applied Forces and Bilateral Muscle Activity of the Back and Shoulders BIBAFull-Text 1397-1400
  William Porter; Sean Gallagher; Carrie Reinholtz; Janet Torma-Krajewski
Hand scaling is a physically demanding job and is responsible for numerous overexertion injuries in mining. This experiment studied rib scaling from an elevated bucket to examine force generation capabilities and electromyographic responses to a prying subtask. Subjects exerted force using two bars (steel and fiberglass) at five target heights. Work height significantly affected peak prying force during scaling activities with highest force capacity at the lowest level (p = 0.0188). Bar type did not affect force generation (p = 0.7843): However, use of the fiberglass bar required significantly more muscle activity to achieve the same force (p < 0.05). It was concluded that miners should scale points on the rock face that are below their knees, and reposition the bucket as often as necessary to do so. Additional research is needed to fully understand the impact of bar type on the physical demands of an entire scaling task.
Impact to the Base of the Palm BIBAFull-Text 1401-1405
  David J. Cochran; Pramod Shinde; Xuedong Ding; Matt Wiley; Terry L. Stentz
This study exposed subjects to impacts to the base of the palm using a pendulum of different masses, possessing different energy levels and different velocities. Force sensing resistors were affixed to the thenar and hypothenar eminences of the hand. The subjects' perception of the severity of the impact, the total area of the force time graph, and the maximum acceleration of the force on the palm were measured and are reported on in this paper. Analyses of variance and stepwise regressions were used to determine the pertinent variables affecting the dependent measures. From the ANOVAs, Energy, Velocity, and to a lesser degree Mass affect the three dependent measures of impact measured. Gender only affected the psychophysical measure and then in conflicting ways. From the regression analyses, Energy appears to be the most important variable in affecting the physical and psychophysical results of an impact and larger skinfold thickness seems to ameliorate the severity of the impact.
Effects of Spatial Constraints on Trunk Kinematics during a Dependent Transfer on an Aircraft BIBAFull-Text 1406-1410
  Brian K. Higginson; Michael J. Pavol
A concern related to air travel by people with disabilities is the risk of low-back injuries while transferring the traveler to or from the aircraft seat. Potential contributing factors to this risk are the spatial constraints imposed by the aircraft's interior. This study investigated the effects of such constraints on the trunk angles, angular velocities, and load moment arm during a two-person dependent transfer between a wheelchair and an aircraft seat. Trunk kinematics were recorded as 33 pairs of subjects transferred a dummy to and from an aircraft seat under unconstrained and constrained conditions. The constraints primarily affected the front transferor, increasing peak trunk flexion, lateral bending, twisting, and load moment arm. Effects on the rear transferor were small and appeared to have offsetting effects on injury risk. The results suggest that the row spacing on an aircraft contributes to low-back injury risk during dependent transfers of travelers with disabilities.

INDUSTRIAL ERGONOMICS: Quality and Ergonomics

Quality and Ergonomics a Panel Discussion BIBAFull-Text 1411-1415
  M. W. Riley; Ram Bishu
The primary objective of this panel is to bring together professionals in the intersecting area of quality and Ergonomics, highlight the current state of research in this topic, and get some directions for future work. Ergonomics and Quality have a natural marriage that can be of mutual benefit to both the areas. Human centered concepts such as motivation, and empowerment are some of the building blocks of TQM, while improving all aspects of human work life quality is the basis for ergonomics. This is all the more important in contemporary economy from two perspectives. Service has become a major player these days and there is human involvement at every aspect of service. Secondly, manufacturing is proceeding towards more and more miniaturization, the result is that every quality function needs human components in its dispensing. This panel will address all these issues. Dr. Carayon will present an overview; dr. Karwowski will talk about traditional manufacturing; Dr. Henriksen will talk about health care; Dr. Garamopadhyay will talk about training, while Dr. Bishu will talk about micro manufacturing.

INDUSTRIAL ERGONOMICS: Analysis of Job Risks

Evaluation of Seat Designs Relative to Transmitted Vehicle Vibration on Underground Mine Transport Vehicles BIBAFull-Text 1416-1420
  Christopher C. Jobes; Alan G. Mayton
The National Institute for Occupational Safety and Health (NIOSH) researchers have investigated seat design issues for the occupants and operators of underground mine transport vehicles relative to whole-body vibration (WBV) and mechanical shock. Considering the ergonomic and engineering improvements made to underground mine shuttle car seats, this study has focused on reducing injury risk by improving seating on transport vehicles such as scoops, mantrips, personnel carriers, and rail-mounted locomotives. Similarly, proposed seat design improvements included layering of various types of viscoelastic foam padding to isolate vehicle occupants and operators from adverse health effects of jarring/jolting exposure. This paper discusses the results obtained from laboratory vibration testing of new seat padding materials in seven configurations at the NIOSH - Pittsburgh Research Laboratory (PRL) showing that careful use of configuration and materials can reduce the operator's exposure to WBV. In addition, results for four mine transport vehicles are presented from field data collection efforts at a Southwestern Pennsylvania mine showing that a NIOSH based design does reduce the operator's exposure to WBV. Finally, the authors discuss efforts to develop and field test seat padding interventions using new padding materials and configurations based on the laboratory test results [The findings and conclusions in this report are those of the author(s) and do not represent the views of the National Institute for Occupational Safety and Health.]
Ergonomic Evaluation of Manual Weeding Practice and Development of an Ergonomic Solution BIBAFull-Text 1421-1425
  Amjad A. Ramahi; Fadi A. Fathallah
Agricultural workers performing manual weeding are exposed to high risks of musculoskeletal disorders to the lower back. Hand weeding exposes workers to sustained static loading to spinal soft tissues, which can lead to the initiation of a cycle of inflammatory response. Assessment of injury risks and investigation of current and new methods of manual weeding are the focus of this study. Nine subjects (7 males and 2 females) participated in this study. Trunk kinematics were monitored while workers performed four weeding tasks using different methods; long- and short-handled weeding (hoe and weed Puller), hand weeding, and a newly developed "Eater". The Eater consists of two conveyor belts working simultaneously in an intermesh design to simulate the pulling and grabbing action of the hands. Hoe weeding is considered a less hazardous alternative to hand weeding with regards to back injuries but, our results showed otherwise. The worker's sagittal position with the hoe weeding was not significantly different from the short-handled tool. Also, workers weeding with the hoe displayed the highest trunk velocities. On the other hand, the Eater showed promising results by significantly reducing biomechanical risk factors. However, productivity results are not as promising.
Injury Risk by Day of the Week BIBAFull-Text 1426-1430
  George E. Brogmus
While there is a growing body of research on the impact of work schedules on the risk of occupational injuries, there has been little investigation into any impact that day of the week might have. 2004 data from the United States Bureau of Labor Statistics (BLS) were used to estimate the rate of injuries and illnesses by day of the week. Data for the number of injuries and illnesses involving days away from work were provided by the BLS Office of Safety and Health Statistics; data for the number of hours worked were estimated from an analysis of the American Time Use Survey database. For each day of the week, the number of cases (injuries + illnesses) per 200,000 work hours was calculated from these data. The data were also stratified by Industry Sector. The analysis revealed clear differences by day of the week that could not be accounted for by variation of day of the week employment in these industries. An association with employee tenure was evident. Weekend trends may overlap with overtime effects. Sundays had the highest rate overall - 40% higher than the average rate. Saturdays had the next highest rate followed by Mondays. Interpretation of these trends and the implications for work scheduling are discussed.
Evaluating the Effect of Fatigue on Cognitive and Visual/Perceptual Performance at the Beginning and End of Each Shift in a 12-Hour Five-Day Rotating Workweek BIBAFull-Text 1431-1434
  Othman Alkhouri; Steve Hall; John Wise; Marvin Smith
The effect of cognitive and visual/perceptual fatigue on shift workers may not be the same for non-shift workers since alternating shifts create enormous disruptions to the circadian rhythms of the workers. The purpose of this study was to measure the effect of fatigue induced by alternating shift schedules on shift workers' cognitive and visual/perceptual performance at the beginning and end of each work shift during the workweek. The primary instrument used in this study was the Automated Performance Testing System (APTS), which is a human performance measuring system containing eight various cognitive and temporal factors tests. The findings suggested that cognitive performance at the beginning of the shift was significantly higher than at the end of the shift but similar degradations in visual/spatial performance were not found.
Noise and Cyclic Loading Effects on Performance and Operator Functional State BIBAFull-Text 1435-1438
  G. E. Conway
Studies that seek to assess work performance in simulated stressful work environments often report no performance decrements as they have typically used over-simplified cognitive tasks that do not challenge the operator's compensatory response, and performance measures not sensitive enough to identify strain states. The present research used cyclic loading and ambient noise manipulations to stretch the adaptive limits of the operators and to determine how performance can show evidence of (potential) breakdown. Hysteresis measures allowed the identification of strain carry-over effects. No effects of noise on performance were found. Task load effects were found only in subsidiary 'secondary' tasks however, with primary task performance protected across conditions. High noise conditions were considered to be more demanding and attracted higher levels of compensatory effort and fatigue, which increased even when task load levels were decreased. The results are considered with respect to Hockey's (1997) Compensatory Control Model, and implications discussed.
Effect of Rater Background on Objectivity of the Rapid Upper Limb Assessment BIBAFull-Text 1439-1443
  Virginia J. Hixson
Insufficient evidence of reliability testing of work-related assessments is a major concern in the field of ergonomics. Objectivity, the ability of a scale or test to be used by raters to come to the same conclusion when examining the same thing, is one type of reliability. This paper presents a detailed exploration of the objectivity of a postural rating scale, the RULA, or Rapid Upper Limb Assessment (McAtamney & Corlett, 1993). Four video tasks were presented to 3 groups of raters. Variables examined were rater years of experience in movement observation, rater experience using the RULA, and rater training in use of the RULA. Objectivity was not identified in any variable. Main effects were present for all variables. Based on the rater sample and the data collected, the RULA cannot be considered an objective tool for communicating or comparing information between raters.

INTERNET: Human Factors on the Web: Past, Present, and Visions of the Future

Human Factors on the Web: Past, Present, and Visions of the Future BIBAFull-Text 1444-1446
  Marc L. Resnick
The Internet has had a tremendous effect on the personal, professional and civic lives of populations around the world. Companies that rely on the Internet for a large portion of their business now make up a majority of the major stock indexes; E-commerce is a growing segment of retail; governments are migrating a large part of their services online; online social networking has become a major part of our interpersonal relationships; and even many religions and social service organizations are creating vast quantities of web content. To mark the 50th Anniversary of the HFES Annual Meeting, this panel presented a historical view of how human factors has influenced the evolution of the Internet and how the Internet has influenced the practice of Human Factors. Panelists were selected based on their unique and diverse experiences in the field. Panelists focused on the history, current practice, and future visions of the interrelationship of human factors and the Internet. After brief introductions, panelists fielded thought provoking questions from the moderator and the audience.

INTERNET: Human Factors on the Internet

Human Factors in the Design of Communities of Practice BIBAFull-Text 1447-1451
  Marc L. Resnick
Social networks are emerging as a powerful tool in a variety of Internet and Intranet domains. Social networking web sites are a popular destination for teenage social groups (Myspace), online dating (Tickle), and business networking (Ryze). A less well-known application is the Community of Practice (CoP). These networks are groups of people with common professional interests who are linked with the intention to enhance their professional practice related to these interests. CoP are often supported through a company Intranet and can be very effective in linking geographically dispersed professionals within an organization. By providing a venue for engagement of like-minded professionals who can communicate, share best practices, and in some cases collaborate on specific activities, CoP can significantly increase the productivity of knowledge workers. Usability is essential to overcome limitations due to participant unfamiliarity with each other, geographic dispersion, the importance of context in the application of knowledge, the asynchronicity of the communication, and the challenges of reputation management in the workplace.
A Multilevel Navigation Aid for Hierarchical Structures: An Innovation Case Study and Empirical Evaluation BIBAFull-Text 1452-1456
  Douglas L. Gardner; Robin D. Thomas; Peter H. Jones
The paper presents a novel user interface (Gardner, et al., 2005) designed by LexisNexis to assist researchers navigating large hierarchical structures. This navigation tool allows users of large hierarchies (e.g., tables of contents or file directories) to select an item (node) in the structure and expand (or collapse) it across multiple levels with a single selection. User evaluation was conducted with no participants training or prior use, finding the interface effective for complex navigation. Nearly a third (of 18) immediately displayed and selected hierarchy levels with no hesitation, even when expanding an entire table of contents section to its lowest level. While these participants were those most experienced with large documents, several less-experienced participants used the interface easily once prompted. While the remainder experienced some difficulties with initial interaction, these were related to context, domain experience, and prior habit rather than tool usability.
Importance of Usability Considerations to Purchase Intention on E-Commerce Website with Different User Groups BIBAFull-Text 1457-1460
  Chen Ling; Gavriel Salvendy
E-Commerce sales grow with unprecedented speed these years. The success of the E-Commerce website can be directly affected by its usability. A survey study was conducted to investigate the effect of 19 usability considerations on user's purchase intention with E-Commerce websites. Responses from 300 web users were obtained and analyzed. Factor analysis reveals that users' purchase intention on E-Commerce website is affected, in descending importance by the following five usability factors: trustworthiness, information access cost, shopping support, ease of comprehension, and hedonic quality. Some interesting differences among user groups of different gender, age, and ethnic background were also revealed, which can be used to guide design efforts for websites targeting special user groups.
Design and Evaluation of Categorical Search Results Interfaces BIBAFull-Text 1461-1465
  Rachana S. Rele; Joel S. Greenstein; Anand K. Gramopadhye
This research investigates the design and evaluation of interfaces for the presentation of search results using categorization. Card sorting study was conducted to design categorized search results interfaces. Eye-tracking technology was utilized to evaluate the designed category interfaces, comparing them with a conventional list interface. Two factors of category interfaces, the approach used to order categories and the number of abstracts initially displayed within each category, are investigated. Forty participants performed two types of tasks, navigation and information search, using a PC integrated with a nonintrusive Tobii 1750 binocular eye tracking system. Performance measures such as time for search and percentage of tasks completed did not reveal significant differences among the category and list interfaces. Process measures such as overall number of fixations, mean fixation durations, and relative change from the baseline pupil diameter also did not show significant differences among the category and list interfaces. Although no significant differences are found, there is a consistent positive trend in the performance, process, and subjective measures that supports design of categorical search results interfaces.

MACROERGONOMICS: Macroergonomics and Patient Safety

Consequential Analysis of Information System Criticality in a Healthcare Organization BIBAFull-Text 1466-1468
  S. J. Perry; R. L. Wears; N. Chozos; C. W. Johnson; K. F. Smith
Implementation of information technology (IT) in healthcare has increased with little attention paid to the consequences of system failures. This qualitative study assesses the organizational understanding of IT vulnerabilities, the potential consequences of failure and system recovery capabilities within a large healthcare facility. Fifty nine percent (59%) of identified software applications were rated mission critical by participants, 46% were medium impact and 1 application was a non-factor. Downtime procedures were in place for only 39% of applications with 30% of those deemed "mission-critical" lacking downtime procedures. Expected recovery time objectives (RTO) and recovery point objectives (RPO) for users were not consistent with those projected by the IT department. A sub-analysis of the emergency department showed a high percentage of mission critical software but only 36% had downtime procedures. Continued inattention to the risks and hazards associated with widely disseminated IT within healthcare represents a continuing and little discussed vulnerability.
Development of a Job Task Analysis Tool for Assessing the work of Physicians in the Intensive Care Unit BIBAFull-Text 1469-1473
  Kara Schultz; Jason Slagle; Roger Brown; Steve Douglas; Brian Frederick; Manisha Lakhani; Jesse Scruggs; Bruce Slater; Matthew B. Weinger; Kenneth E. Wood; Pascale Carayon
This paper describes the development of a job task analysis tool for observing and recording physician tasks in the ICU. Real-time direct observations were conducted by outside observers using a computerized data collection tool developed to document the tasks performed by ICU physicians. The aim of the analysis was to quantify the tasks of the physicians, including measures of frequency, duration, and sequence for tasks. In this paper, we report on the development process, as well as the validity and reliability of the job task analysis tool. Initial results from our analyses provide support for the validity and reliability of the taxonomy developed for assessing work of ICU physicians.

MACROERGONOMICS: Using Technology to Enhance the Organization

Macroergonomic Principles of Automated Performance Measurement BIBAFull-Text 1474-1477
  Eric Dunsker
Retail associate productivity has increased dramatically over the last 15 years with the use of ever more sophisticated scanners and point of sale (POS) terminals. Data warehouses enable businesses to store remarkable detail about each transaction. Analyses of these data tend to focus on the items sold and money collected. However, if these systems also collect timestamp data of important events during transactions retailers would then have the basis for measuring associate activity.
   This paper discusses the macroergonomic principles that must guide the design of cashier performance measurement systems in the retail setting. Following these guidelines leads not only to increased manager effectiveness, but also to more accurate measurement of activity. It can also improve associates morale and the likelihood of incenting desirable and productive behaviors. These principles are generalizable to other domains in which automated performance measurement takes place.
Acceptance of Computer Technology: Understanding the User and the Organizational Characteristics BIBAFull-Text 1478-1482
  Sung Park; Marita A. O'Brien; Kelly E. Caine; Wendy A. Rogers; Arthur D. Fisk; Koerts Van Ittersum; Muge Capar; Leonard J. Parsons
A systematic analysis of acceptance of computer technology was conducted to identify variables that would provide insight to understanding technology acceptance. This led to a development of a comprehensive qualitative model that captures the individual and the organizational user characteristics that influence the acceptance of computer technology. This model suggests that designers must be mindful of the role that sociological and organizational variables play in technology acceptance. Such factors go beyond basic usability issues in the design process. Attention to these variables may increase the acceptance and therefore the diffusion of new computer technologies.
A Case Study in Using Macroergonomics as a Framework for Business Transformation BIBAFull-Text 1483-1487
  Faith McCreary; Kunjan Raval; Meghan Fallenstein
This paper presents the results of a case study of an approach for simultaneously investigating an organization's user experience and driving user-centric change within the larger organization. Called Model Workplace, it is a collaborative, macroergonomics-based approach that leverages the business expertise native to an organization with that of user research consultants to gather diagnostic information at all levels of the user experience for informed organizational decision-making. This innovative approach is as much about changing an organization so that it can make more effective use of the research data, as it is about gathering the data needed for effective change. Our findings suggest that this approach can be used by other organizations to drive customer-focused change throughout their business plans and processes.
A Theoretical Framework of Risk Compensation in Supply Chain Management Decision Making BIBAFull-Text 1488-1491
  David M. Neyens; Linda Ng Boyle
The goal of this study is to develop a theoretical framework for the study of decision makers within supply chains. Decision makers may compensate inappropriately by overstocking or overestimating lead times resulting in greater inventory costs. By leveraging the knowledge associated with risk compensation, better accountability of logistics and inventory holding costs can be achieved. Although there are conflicting views on risk compensation, the theory does provide insights into the complexities facing the decision maker in supply chain environments. More specifically, there has been relatively little research examining how human factors issues impact the supply chains' effectiveness. The risk compensation framework is tailored to represent and model the inventory management portion of the supply chain and can be validated through experimentation by evaluating the operator's perceived risks. In developing this model, the foundations for extending our knowledge of the human decision making in supply chain management can be established.
Usability and Probabilistic Modeling for Information Sharing in Distributed Communities BIBAFull-Text 1492-1495
  Sudip K. Ghosh; Barrett S. Caldwell
This paper describes work done in developing realistic simulations of information sharing in distributed expert communities. Instead of a rule-based rational behavior approach, we take a probabilistic modeling approach for studying group performance and time-constrained, socially-mediated tasks. Four simulation modules for advising, sharing, solving and learning had been proposed and are in development. This work presents research done using an online blog to gather supporting usability data for the second module. This is put in context of earlier work suggesting use of the above simulation modules. We present data from two studies suggesting the importance of social interaction in distributed expert communities. The results presents make a strong case for using the proposed simulation modules as a design and usability tool.

MACROERGONOMICS: Macroergonomics in Decision Making, Teams, and Health Care

Predicting Performance: Self-Esteem Among Soldiers Attending Health Care Specialist Training BIBAFull-Text 1496-1500
  Valerie J. Rice; Jenny Butler; Diane Marra
Reducing failure and recycling in demanding military Advanced Individual Training (AIT) programs will reduce costs: time and morale for the Soldier and financial costs for the organization. This study is one in a series, examining factors internal and external to the Soldier that can influence performance during AIT. The purpose of this research was to document self-esteem among 253 Soldiers attending Health Care Specialist Training using the Rosenberg Self-esteem Survey and to examine the relationship between self-esteem, general demographics, self-reported health, motivation, self-efficacy and grade point average (GPA). Self-reports of self-esteem were categorized as 11% low, 37% moderate, and 52% high. No relationship was found between self-esteem and gender, marital status, age, race, military component or high school GPA or science grades (p>0.05). Self-esteem was correlated with self-reported health status, endurance, strength, self efficacy and motivation (p< 0.05). No relationship was found between self-esteem and GPA.
Formative Evaluation of a Rapid Universal Safety and Health (Rush) System for Construction BIBAFull-Text 1501-1505
  Brian M. Kleiner; Tonya Smith-Jackson; Elizabet Haro
Rapid construction projects and processes will become increasingly important in the aftermath of natural and/or unnatural disasters. For use in expedited projects (as well as traditional projects), a Rapid Universal Safety and Health system (RUSH) was designed, developed and deployed. For its inaugural application, the RUSH was applied to a 106 hour residential construction project. This paper presents the formative evaluation based upon on-site data collection and a survey instruments administered just after the project to trades, managers and safety team members. No major incidents were recorded. The results will be discussed in terms of the observational and survey results.
A New Approach to the Measurement of Work Related Musculoskeletal Disorders BIBAFull-Text 1506-1509
  P. Hoonakker; S. Simmons; P. Carayon; R. Warren
In many studies, a standardized symptoms checklist is used to measure work-related musculoskeletal disorders. Most questionnaires include measures of prevalence, severity and frequency, but little is known about how to combine these measures. One approach for combining various measures of prevalence, frequency and severity is Latent Class Analysis (LCA) that allows for the assessment of the structure of the relationships among the various aspects of reported symptoms. In this paper we explore the use of Latent Class Analysis to analyze the relation between job characteristics and musculoskeletal disorders in the Wisconsin Longitudinal Study (WLS) data 1992-2004.
Role of Human Factors Engineering in Improving Employment Outcomes Among Cancer Survivors BIBAFull-Text 1510-1513
  Mary E. Sesto
What role will human factors engineers and return to work professionals play in addressing the needs of cancer survivors in return to work? The National Cancer Institute estimates that there are 10.1 million cancer survivors in the United States. Of these, 3.8 million are working age adults (ages 20 to 64) (2005). Due to early detection and treatment improvements, the length of survival has increased. Unfortunately, survivors may experience short term and long term side effects (physical, psychosocial and cognitive changes, and fatigue) from treatment that result in functional limitations that may affect their work productivity or their ability to return or continue in the work place. Although the majority of human factors engineering/ergonomics and return to work research has focused on occupational injuries and illnesses, the application of this information to employment issues encountered by cancer survivors may be extremely beneficial.
Team Resource Foraging in Event-Driven Task Environments BIBAFull-Text 1514-1518
  Sandra K. Garrett; Barrett S. Caldwell
Although applied in a number of fields (including information science and human-computer interaction), foraging theory has not been used to study role differentiated team dynamics in an event driven environment. Many critical assumptions must be modified and the operational definitions must be enhanced for the theory to be applied in these more complex settings. This paper focuses on research developments leading to conceptual elaborations and expansions of the resource foraging framework, in order to address team-based resource acquisition and utilization strategies. The additional foraging concepts and definitions presented in this paper derive from the authors' research in spaceflight operations and healthcare delivery environments. In the authors' current healthcare research, appropriate resource foraging strategies vary dramatically based on specific healthcare setting, team structure, and other factors. These findings help to empirically validate the expanded construct of resource foraging by teams.

PERCEPTION AND PERFORMANCE: Spatial Displays and Spatial Cognition

Alignment Effects on Simple Turn Decisions in Track-Up and North-Up Maps BIBAFull-Text 1519-1522
  Derek Viita; Steffen Werner
Turn decisions will be slower and less accurate for misaligned orientations of a map than when the map is aligned with one's heading direction. It is unclear what the size of this effect will be for misalignments within a narrow range around the aligned heading. This series of experiments examined the effect of turn-arrow alignment on accuracy and speed of turn decisions. In the first experiment, participants were presented with a series of maps, each with a turn arrow of a different orientation and heading superimposed over the center. The second experiment added a simulated driving task to increase cognitive load. Results indicate that while error rates and reaction times rise with increased misalignment, a wide range of misaligned headings ±50° around the perfectly aligned heading show error rates and reaction times that are not significantly different from the aligned heading and thus produce little cognitive cost.
Congruency Between Visual and Auditory Displays on Spatial Tasks Using Different Reference Frames BIBAFull-Text 1523-1527
  Nada J. Pavlovic; Jocelyn Keillor; Mark H. Chignell; Justin G. Hollands
This study investigated the effectiveness of spatial auditory cues for tasks using different reference frames, and examined how congruency between auditory and visual displays affected performance. Performance with three types of auditory cues (egocentric, exocentric and non-spatial) was compared on three spatial tasks: target search, target localization and target recall. There was a clear effect of reference frame congruency between auditory and visual displays on target search and target localization tasks. Interestingly, even incongruent auditory cues improved performance relative to non-spatial control conditions. In addition, egocentric auditory cues facilitated performance more than exocentric cues on incongruent trials. The findings have important implications for display design in work environments that involve diverse spatial tasks and displays that use different reference frames.
The Effects of Camera Perspective and Field of View on Performance in Teleoperated Navigation BIBAFull-Text 1528-1532
  Skye Lee Pazuchanics
Directly teleoperated uninhabited ground vehicles (UGVs) can grant field teams access to places and information previously unavailable. Despite their capability, the video from these vehicles can make teleoperated navigation difficult by cutting out valuable information about the spatial context around the UGV. Typically, UGV cameras provide their operators with a very narrow, "soda straw" field of view (FOV) and a first-person camera perspective. The present research investigated two methods for providing an operator with additional contextual information: widening the FOV and capturing a third-person perspective of the vehicle in its environment. The results indicate that the additional information provided by either method can facilitate aspects of navigation performance. Of the two methods, widening the FOV produced the greatest performance benefit in our task. However, if the FOV cannot be widened, the results suggest that capturing a third-person perspective may facilitate certain aspects of navigation. Finally, the benefits associated with each method were found to be additive. This result suggests that ideal video displays may incorporate both methods, but further research is necessary to understand how the specific information provided by each method impacts the many types of tasks involved in teleoperated navigation.
Effects of Spatial Intelligence and Gender on Wayfinding Strategy and Performance BIBAFull-Text 1533-1537
  C. M. M. Hurts
In a wayfinding field study the effects of spatial intelligence and gender on wayfinding strategy and the amount of configurational wayfinding knowledge were investigated. This was done in an attempt to shed some additional light on the mixed evidence regarding the precise role of these factors yielded by previous studies. Subjects were asked to describe a route in a familiar city using landmark-based directions and route-based directions (e.g., go-left, go-straight). Configurational knowledge was measured by having subjects position a number of well-known buildings on a schematic map of the same city. Familiarity with the city was used in the analyses as a covariate. Results show that men tend to report more route-based directions, relative to landmark-based directions, than women do. Men also have better configurational knowledge. These effects could not be attributed to the person's score on a spatial intelligence test and the person's familiarity with the city. However, spatial intelligence was not related to the type of wayfinding directions preferred (landmark-based or route-based), nor to the quality of configurational knowledge. Practical and theoretical implications are indicated.
The Effect of a Speech Discrimination Task on Navigation in a Virtual Environment BIBAFull-Text 1538-1541
  Bruce N. Walker; Jeffrey Lindsay
If the input from the visual system is unavailable (e.g., damage to the optic nerves or smoke in a burning building), navigating and avoiding obstacles becomes very challenging. It is therefore desirable to develop a navigation aide for use where visual input has become unavailable. There is a small body of research concerning such navigation aides and their efficacy. However, many issues that may have serious human factors repercussions for such a system are unexplored. This study was conducted in order to examine the effect of an attentionally demanding distractor task on wayfinding performance with an audio only navigation aide, in this case the System for Wearable Audio Navigation (SWAN). A difficult secondary speech task reduced efficiency in navigation, as users switched attentional resources to the speech task. Practical applications are discussed.

PERCEPTION AND PERFORMANCE: Tactile Perception and Multimodal Displays

Multimodal Interfaces: A Framework Based on Modality Appropriateness BIBAFull-Text 1542-1546
  Jan B. F. van Erp; Frank L. Kooi; Adelbert W. Bronkhorst; David L. van Leeuwen; Myra P. van Esch; Sander J. van Wijngaarden
Our sensory modalities are specialized in perceiving different attributes of an object or event. This fact is the basis of the approach towards multimodal interfaces we describe in this paper. We rated the match between 20 possible information attributes (common in human computer interaction) and the visual, auditory and tactile sensory systems. We refer to this match as modality appropriateness. Preferably, an information chunk is allocated to the most appropriate modality. In situations in which information consists of several attributes, these may be allocated to different modalities. This approach is in contrast with the more common approach in which multimodality is implemented in an interface as a redundant presentation of the same information to two or more sensory modalities. This latter approach can be beneficial to solve risks of sensory overload and to make the interface accessible for people with a sensory challenge, but is not based on possible synergy between the senses. However, the supposed synergy may also involve costs, for example in terms of the time required to switch between modalities and in the introduction of additional noise in cross-modal comparisons compared to unimodal comparisons. We will discuss both the chances and the potential costs of applying the modality appropriateness framework.
Vibrotactile and Visual Threat Cueing with High G Threat Intercept in Dynamic Flight Simulation BIBAFull-Text 1547-1551
  Lars Eriksson; Jan van Erp; Otto Carlander; Britta Levin; Hendrik van Veen; Hans Veltman
In a TNO and FOI joint study, nine fighter pilots participated in a threat detection and intercept experiment in the Swedish Dynamic Flight Simulator. Visual threat cueing with a simulated Gripen aircraft head-up display (HUD) symbology was compared with combined visual and vibrotactile threat cueing by means of the HUD symbology and a TNO Tactile Torso Display consisting of 60 vibrators in a matrix covering the pilot's torso. Each fighter pilot detected and intercepted 32 threats while pulling G-loads up to +8-9Gz. The high G-loads neither critically affected the tactile vest equipment nor the human sensory system, and visual/tactile cueing generated an overall faster RT to threat pop-ups compared with visual cueing alone. The pilots' highest ratings of the tactile cueing were for capturing attention and indicating initial threat direction at threat pop-up. Thus, tactile threat cueing could enhance visual cueing and threat awareness in fighter aircraft.
Uni- and Bimodal Threat Cueing with Vibrotactile and 3D Audio Technologies in a Combat Vehicle BIBAFull-Text 1552-1556
  Otto Carlander; Lars Eriksson
An experiment investigated uni- and bimodal cueing of horizontal threat directions to the driver of the Combat Vehicle 90 (CV 90). 3D audio in headphones or tactile vibration onto the torso, or both in combination were utilized for threat cueing. Ten male CV 90 drivers from the Swedish Army Combat School were required to turn the vehicle toward the threat as quickly and accurate as possible. Each driver handled 45 threats in total. Each of five threat directions was presented three times for each of the three threat cueing conditions. The results show that the drivers had good overall performance, albeit the 3D audio needs improvement with regard to front - back confusion if not used with tactile cueing. That is, the 3D audio generated greater localization errors and reaction times with threats straight behind the vehicle compared with the tactile and the 3D audio/tactile combination, respectively.
Evaluation of Human Vibration Thresholds at Various Body Loci BIBAFull-Text 1557-1561
  M. Bikah; M. S. Hallbeck; J. H. Flowers
Researchers at the University of Nebraska - Lincoln are currently designing a vibrotactile alerting mechanism for a neutron sensor. The instrument will vibrate on users' skin in the presence of high levels of neutron radiation. The head, neck, upper arm, wrist, waist, and ankle are potential body placements for the device. However, there is minimal information about the vibration frequency thresholds at those body sites. The investigators divided the aforementioned body loci into 24 stimulation sites representing orthogonal directions at each site. The objective of the study was to investigate the underlying effect of stimulation site, subcutaneous fat, and gender on low frequency vibration perception thresholds. Thirty-six subjects were categorized into a dichotomous body fat content group and gender. The results show that vibratory threshold depends significantly on the body site stimulated (p = 0.001). The site with the lowest frequency threshold was the nape of neck while the right lateral area of the waist had the highest frequency threshold. There was no statistical difference in frequency thresholds for the variables of the body fat group or gender (p = 0.302, p = 0.159, respectively). Although, the mean frequency thresholds of participants in the low body fat group was consistently lower than that of those in the high body fat group.
The Effects of Physiological Stress on Tactile Communication BIBAFull-Text 1562-1566
  James L. Merlo; Shawn Stafford; Richard Gilson; P. A. Hancock
The researcher-constructed tactile display prototype has been used to conduct a variety of laboratory studies that have demonstrated positive results for tactile signaling and communication. This prototype display that uses precision tactors and skilled placement of them exhibits potential for superior reception of the vibration in the appropriate skin receptors. The purpose of this study was to determine if this prototype tactile display could still produce accurate reception of tactile localization and messaging under physiological stress. Results showed that USMA cadets running on a treadmill had almost error free performance, demonstrating that messaging and localization of tactile signals seemed to be unaffected by physiological arousal or stress.

PERCEPTION AND PERFORMANCE: Auditory Perception and Displays

Binaural Audio Symbology for Urgency Displays BIBAFull-Text 1567-1570
  Mark A. Ericson
Five experiments were conducted to study the acoustic attributes that enable the accurate identification and localization of rudimentary spatial warning sounds. In each experiment, two sounds were played simultaneously over loudspeakers at various azimuths and elevations. The stimuli consisted of pure tone complexes with a 13 kHz bandwidth. The fundamental frequencies, the amplitude modulation rate of the complex, the harmonicity of the carrier and modulation frequencies, and the coherence of the carrier and modulation phase were varied in the experiments. The combination of all the cues provided the best localization and identification performance. When and only when all cues were used, the subjects were able to accurately localize and identify the target sound.
Lateralization of Sounds Using Bone-Conduction Headsets BIBAFull-Text 1571-1575
  Raymond M. Stanley; Bruce N. Walker
Participants reported the apparent lateralization of sounds as a function of interaural level differences, for stimuli delivered through bone-conduction headsets and standard headphones. The results showed that non-externalized spatial audio can be invoked with the bonephones, a device that provides the unique advantage of not covering the ears of the listener. Furthermore, the degree of lateralization with bonephones can be similar to that produced using headphones. These data provide a function relating the input into bonephones or headphones to the resulting percept of lateralization, in a manner that may be particularly useful for mobile and low-resource computing applications.
The Elevation Illusion in Virtual Audio BIBAFull-Text 1576-1580
  Dennis J. Folds
Virtual audio involves headphone presentation of sound that appears to originate from an external location. Perception of elevation is known to be less accurate for virtual audio than for real sources. Anecdotal evidence suggests that at least some listeners have a pronounced tendency to consistently perceive the virtual audio as elevated higher than intended. The present study was conducted to investigate and compare errors in perception of elevation for virtual and real sources. Eight subjects listened to sounds presented through loudspeakers (behind an acoustic curtain) and through headphones (as virtual sources), and reported their perceived elevation for each sound. Five elevations were used (two above, two below, and one at ear level). The results show near perfect performance for perception of elevation for the loudspeaker condition. Perception of elevation was far less accurate for the virtual sources, and some subjects consistently perceived virtual sources higher than intended.
Using 3D Audio Guidance to Locate Indoor Static Objects BIBAFull-Text 1581-1584
  Samuel Sandberg; Calle Hakansson; Niklas Elmqvist; Philippas Tsigas; Fang Chen
Is 3D audio an interesting technology for displaying navigational information in an indoor environment? This study found no significant differences between map- and 3D audio navigation.
   The user tasks tested involved finding objects in a real office environment. In order to conduct the study, a custom-made 3D audio system was built based on a public-domain HRTF-library to playback 3D sound beacons through a pair of earphones. Our results indicate that 3D audio is indeed a qualified candidate for navigation systems, and may be especially suitable for environments or individuals where vision is obstructed, insufficient, or unavailable. The study also suggests that special cues should be added to the pure spatial information to emphasize important information.

PERCEPTION AND PERFORMANCE: Motion Processing

Effects of Motion on the Perception of Static Features in a Display BIBAFull-Text 1585-1588
  Douglas J. Gillan; Connor T. Gillan
Displays that use motion typically contain both dynamic and static features. We hypothesized that, relative to a no motion condition, representational momentum (the forward displacement of the representation of a moving object) might influence the perception of static distance between two objects when the objects had just moved away from each other or just moved toward each other. Two experiments tested the hypothesis by manipulating the end distances between two moving dots and the type of motion (Motion Away, Motion Towards, No Motion). In Experiment 1, the distance that the dots moved was the same for all six end distances, whereas in Experiment 2, the distance moved was proportional to the end distance. Participants estimated the distance at the end of the motion on every trial. The results of both experiments showed that the Motion Away produced greater estimates of distance than the other conditions. This effect was most pronounced at the longest end distances in Experiment 2. The results suggest designers should be cautious in using motion in displays for tasks that involve estimates of static distance.
Active regulation of speed during a simulated low-altitude flight task BIBAFull-Text 1589-1593
  April M. Bennett; John M. Flach; Tim R. McEwen; Sheldon M. Russell
This study examined active regulation of speed during a low-altitude flight task as a function of global optical flow rate, speed, and the presence or absence of a concurrent altitude disturbance. The results showed that altitude clearly had an impact on speed control. Control of speed was much more difficult when altitude disturbances were present. Even in the no altitude disturbance conditions, performance tended to be best at lower altitudes. Consistent with previous research, the results suggest that speed and altitude changes have additive effects on speed judgments. This is inconsistent with the simple global optical flow rate hypothesis that had suggested multiplicative effects. However, it is consistent with the general notion that judgements of self motion are based on properties of optical flow fields (i.e. angles and angular rates) that depend on distance and motion relative to textured surfaces.
Perspective Dependence on Direction Judgment in a Virtual Room Space BIBAFull-Text 1594-1598
  Zhiqiang Luo; Henry Been-Lirn Duh
The present study investigated the role of encoding perspective in mental representation for the spatial layout learned via the route, leaning and aerial perspectives which are different with respect to the height taken. Two experiments with the same procedures were carried out in two different virtual rooms. The results showed that the direction judgment, especially the vertical angle judgment, was changed as the perspectives varied along the vertical dimension of space. In addition, the room geometry can also influence the mental representation of spatial relations. The data indicated that the orientation-dependent property of spatial memory can be formed when the perspective varies along the vertical dimension of space.
On Reducing the Somatogravic Illusion with HMD Conveyed Visual Flow BIBAFull-Text 1599-1603
  Lars Eriksson; Arne Tribukait; Claes von Hofsten; Ola Eiken
The acceleration-induced somatogravic illusion (SGI) is part of the pilot spatial disorientation (SD) problem. The effect of visual flow on the SGI was investigated in 13 non-pilots equipped with a head-tracked head-mounted display (HMD) in a human-use centrifuge. The participant was seated in a fixed gondola facing the rotation center of rotation of the centrifuge, and by increasing the angular speed of the centrifuge the centripetal acceleration was increased from near-zero to 0.57Gx. The final gravitoinertial force vector was 1.15G corresponding to a 30° pitch-up. During acceleration of the centrifuge, the participant viewed either a HMD presentation of moving texture elements beneath a stationary horizon, representing a forward linear acceleration, or a darkened HMD without any orientation cues. By means of an adjustable plate the participant continually indicated the perceived horizontal plane. Although there was a great inter-individual variability in the magnitude of the SGI, the overall results suggest that HMD conveyed visual flow might reduce SGI in non-pilots.
Peripheral Motion Displays: Tapping the Potential of the Visual Periphery BIBAFull-Text 1604-1608
  Frank L. Kooi; Marcel Mosch
We address the challenge to develop a "peripheral display" with information readable from the corner of the eye. This interest is spurred by the need to convey information outside the central vision, in order to allow the operator the freedom to look elsewhere in the world. We show that low contrast motion patterns are particularly suited. The information capacity is sufficient for at least 10 messages and, perhaps surprisingly, peripheral motion messages distract little. The messages can intuitively be categorized as "urgent" and "not-urgent". With the peripheral motion designs overlaid on a route navigation system we demonstrate 1) the excellent peripheral readability, 2) intuitive coding of urgency, and 3) minimal effect on the readability of the standard navigation information.

PERCEPTION AND PERFORMANCE: Vigilance and Brain States

Performance, Workload, and Stress in Vigilance: The Power of Choice BIBAFull-Text 1609-1613
  J. L. Szalma; P. A. Hancock
Observers were provided the illusion of choice by permitting them to 'choose' an easy or a hard version of a vigilance task. Participants were then assigned at random to either the condition they expressed preference for or their non-preferred condition. Participants in the comparison control condition were not offered the opportunity to choose. Task demand was manipulated using event rate variation, divided into high and low event rates. Results indicated that permitting participants a choice regarding 'difficulty level' and subsequently assigning them to that level enhanced signal detections but did not reduce their perceived workload and stress. In contrast, offering a choice and then assigning observers to their non-preferred condition impaired performance relative to a condition in which no choice was provided. This pattern of effects was more pronounced at the low compared to the high event rate. These results confirm the importance of motivational effects in vigilance and the impact choice has on performance in tasks requiring sustained attention.
Measuring the Workload of Sustained Attention BIBAFull-Text 1614-1618
  Victor S. Finomore; Joel S. Warm; Gerry Matthews; Michael A. Riley; William N. Dember; Tyler H. Shaw; Nathaniel R. Ungar; Mark W. Scerbo
The utility of a new measure of perceived mental workload in vigilance, The Multiple Resources Questionnaire (MRQ), was evaluated by comparing its sensitivity against that of the standard measure in this area, the NASA-TLX. Sensitivity was assessed in regard to the effects of a factor previously shown by the NASA-TLX to affect task demand, detecting stimulus presence/absence. Performance efficiency was significantly greater when critical signals for detection were defined by the presence of a target feature than by the absence of that feature. This effect was echoed in higher global workload scores for absence than presence when workload was measured by the NASA-TLX and by a modified version of the MRQ involving an increase in the response range for each item in the scale. Additionally, the MRQ identified resources utilized in the vigilance task that are not reflected in the standard measure. The results indicate that the new scale could be a useful adjunct to the older one.
Effects of Sensory Modality on Vigilance Performance and Cerebral Hemovelocity BIBAFull-Text 1619-1623
  Tyler H. Shaw; Joel S. Warm; Gerald Matthews; Michael Riley; Ernest M. Weiler; William N. Dember; Lloyd Tripp; Victor Finomore; Todd D. Hollander
Using Transcranial Doppler sonography, cerebral blood flow velocity (hemovelocity, CBFV) was recorded from the middle cerebral arteries during the performance of 40-min auditory and visual vigilance tasks. Reductions in stimulus duration were the critical signals for detection in both tasks, which were equated for stimulus salience and discrimination difficulty. Signal detection responses (correct detections and false alarms) and CBFV declined linearly over time in both modalities. In addition, the overall level of CBFV and the temporal decline in this measure were greater in the right than the left cerebral hemisphere. The results support the view that a right hemispheric system is involved in the functional control of vigilance and that this system operates in a similar manner in the auditory and visual channels.
Exploring Eye Tracking Measures to Understand Operator Performance BIBAFull-Text 1624-1628
  Dervon Chang; Sven Fuchs; Laura Milham; Meredith Bell-Carroll; Kay Stanney
Eye tracker technology is a growing and viable source for more sensitive, unobtrusive, and objective measures of operator performance and cognitive state. Several eye movement metrics have been validated in the empirical literature, but caution is advised when linking low level eye movements (e.g., fixations) to high level cognitive constructs (e.g., workload). Valid analysis of eye movement data is vulnerable to output interpretation, metric granularity, and incomplete views of operator performance. To address these issues, more research is needed to exploit contextual information from other performance measures, identify metric deficiencies, and develop useful composite measures. Individual eye movement metrics alone provide an insufficient picture of operator cognition and performance, but when purposefully combined with other metrics (e.g., other physiological sensor data), offer a more comprehensive look at operator performance. Understanding why operator errors occur can help researchers identify information-processing bottlenecks, possibly allowing designers to find ways to improve performance.
Broad-Spectrum Mitigation and the Cognitive Neurobiological Interface: considering biological rhythms in Augmented Cognition BIBAFull-Text 1629-1633
  Bradly Alicea
Brain-computer interface design relies upon mitigating human performance. Recent attempts have focused mainly on real-time cognitive processing. This paper will consider biological rhythms as a longer-term and more dynamic factor for determining human performance in such systems. To characterize the contribution of such neurobiological phenomena to human performance, biological rhythms will be proposed as the input for both "sub-cognitive" state gauges and a predictive model based on complexity theory that modulate the input/output properties of basic cognitive state gauges. The relationship of biological rhythms to cognitive processing exists at multiple temporal scales, and provides an additional level of complexity to currently held conceptual models. Most notably, a concept called broad-spectrum mitigation will be considered as a way to improve human performance and more effectively augment cognitive processing.

PERCEPTION AND PERFORMANCE: Attention

Fluorescent Colored Stimuli Automatically Attract Visual Attention: An Eye Movement Study BIBAFull-Text 1634-1637
  Frank Schieber; Nick Willan; Ben Schlorholtz
Fluorescent colored materials possess qualities that can lead to enhanced visibility and safety. However, little is known about the mechanisms that mediate this enhanced visual conspicuity. Previous studies using visual search paradigms suggest that the enhanced conspicuity of fluorescent colors stems from top-down attentional mechanisms; and, offer no support for the claim that fluorescent colored stimuli can automatically attract visual attention in a strictly bottom-up fashion. As an alternative to visual search techniques, the present study investigated eye movement behavior to ascertain whether an unexpected presentation of a fluorescent colored stimulus would be likely to capture initial visual fixations to the onset of a multi-stimulus array. Results of the study indicate that, compared to non-fluorescent colored stimuli, the fluorescent colored target was much more likely to elicit initial fixations. Contrary to previous studies, these findings support the claim that fluorescent colors can automatically attract visual attention via bottom-up mechanisms.
Does a Head-Mounted Display Worsen Inattentional Blindness BIBAFull-Text 1638-1642
  Stas Krupenia; Penelope M. Sanderson
Head mounted displays (HMDs) can present visual information to operators at times when this would otherwise be difficult or impossible using standard visual displays. HMDs have been shown to benefit anesthetists in simulated medical environments. Operators, however, may have trouble extracting information from the HMD in dynamic environments. Operators may also fail to consciously perceive visual events that are important, meaningful, or bizarre if attending to other aspects of the visual scene. We investigated how attention manipulations (Focused, Divided, Just Watch) interact with display type (HMD, Standard Display) and found that participants were less likely to detect unexpected events using the HMD. We also found that unexpected event detection decreased from the Just Watch to Divided to Focused attention conditions. We suggest further testing be taken to ensure that HMDs to not result in failures to detect unexpected events in anesthesia monitoring.
Reducing Uncertainty in Visual Search Through the Priming of Visual-Relatedness and the Manipulation of Observer Expectancy BIBAFull-Text 1643-1646
  Kenneth Hailston; Elizabeth T. Davis
We examined two means of reducing uncertainty in visual search: 1) visual-relatedness of a prime to a target and 2) expectancy (based on the proportion of validly primed trials). The two processes were decoupled using a short and a long inter-stimulus interval to examine their respective time courses in visual search. Twelve participants engaged in a discrimination task and a visual search task. The obtained results suggest that visual-relatedness affects search performance early, but its effects rapidly decay. They also suggest that expectancy requires time to accrue before it can affect visual search performance, but its effects are more long lasting than visual-relatedness. These results offer guidance for designing visual displays. In tasks that require split-second decisions designers should be encouraged to prime visual-relatedness. Moreover if the onset of the display and the required decision are separated by a longer interval, displays should inform users of likely outcomes (i.e. manipulate user's expectations).
Does a Multi-Layer Display Reduce the Effect of Non-Target Flankers BIBAFull-Text 1647-1651
  S. M. Carr; J. W. Meehan; J. G. Phillips
Pointing movements to targets may be influenced by non-target flankers. A Multi Layered Display (MLD) was used in an attempt to reduce any distracting effects of flanking targets. A 'response vector model' predicts movements away from highly salient flankers, while a 'response activation model' can predict movements towards. Participants were 14 skilled computer users who moved a computer cursor using a mouse to virtual targets. Kinematic analysis revealed significant effects consistent with the response vector model. Separating target and flanker separation using the MLD reduced the distracting effects of flankers upon the early "planned" part of cursor trajectories but not the latter part of cursor trajectories.
Expertise Differences in Attentional Control Between and Within Baseball Batters BIBAFull-Text 1652-1655
  Rob Gray
A simulated baseball batting task was used to investigate the role of attention in hitting performance for expert and novice baseball players. In Experiment 1, we compared the relative effects of attending to stimuli in the external environment (tone frequency) and attending to skill execution (bat movement) on batting performance for college players. When non-switch hitters batted from their preferred plate side or switch-hitters batted from either plate side, attending to the external environment had no significant effect relative to single task performance while attending to skill execution degraded batting performance. When non-switch hitters batted from their non-preferred plate side the exact opposite pattern of results was found. In Experiment 2, we compared the relative effects of attending to stimuli in the external environment presented either within or between swings for novice and expert batters. For experts, attending to the external environment had no significant effect relative to single task performance in the within condition but significantly degraded performance in the between condition. Novices showed the exact opposite pattern of results. These findings are consistent with the dominant theories of skill acquisition and indicate that the optimal attentional focus varies substantially across and within performers of different levels of expertise.

PERCEPTION AND PERFORMANCE: Perception and Control Tasks

Effects of Roadway Visibility on Steering Errors While Driving in Blowing Snow BIBAFull-Text 1656-1660
  Roger Lew; Brian P. Dyre; Brian Wotring
Simulations of driving over a randomly-textured ground plane produce systematic steering errors when falling snow moves orthogonally to the driver's path (Dyre & Lew, 2005). Here, we examined whether these errors are mitigated by either high- or low-visibility roadways. Drivers viewed simulations of driving across a ground plane while snow moved at different speeds orthogonal to the initial direction of movement, which varies the angular distance between the focus of expansion (FOE) defined by the snow and the FOE defined by the environment. Drivers were instructed to steer such that they maintained a straight path relative to the ground. Three roadway visibility conditions were examined: no visible roadway, low-visibility roadway, and high-visibility roadway. Errors in steering and maintenance of lane position were related to the angular distance between the FOE for all roadway visibility conditions, although the magnitude of the errors lessened when low- and high-visibility roadways were present.
Terrain Orientation Theory for a Visual Approach to Landing BIBAFull-Text 1661-1665
  Randy Gibb; Rob Gray
Terrain Orientation Theory for the visual guidance of an approach and landing is based on glide path perception dependent upon the orientation of the landing surface due to global and local features. Numerous studies have attempted to determine the primary cues used to visually guide an aircraft to landing during rich viewing conditions and during black hole or featureless terrain conditions. Research has focused on the runway and the horizon. No one model or theory however has yet to capture all aspects of the perceptual approach to landing process. Previous studies have implied the role of surface orientation and terrain but failed to manipulate conditions throughout the entire approach and landing to account for robust conclusions.
The Magnitude of Motion Parallax Affects Control of Egospeed BIBAFull-Text 1666-1669
  Brian P. Dyre; Stacey Cooper; Roger Lew; Brian Wotring
Perceiving the speed of self-motion, or egospeed, from optical flow can be important for vehicular control. McDevitt, Eggleston, & Dyre (1999) found that judgements of egospeed are affected by the magnitude of motion parallax present in optical flow. The present study examined whether this motion parallax effect generalizes to control of egospeed. Participants were shown simulations of forward translation parallel to a set of three transparent planes defined by white dots and separated by a constant interplane distance. After a preview period, the motion parallax produced by the set of three planes was instantaneously changed by changing the interplane distance. Participants then reduced their egospeed to one-half that experienced during the preview period. Decreases in motion parallax resulted in higher adjusted speeds, while increases in motion parallax resulted in lower adjusted speeds. These results suggest that control of egospeed is affected by motion parallax in the same manner as judgments.
Study on the Operator's Mental Activity Under Unexpected Control System's Condition BIBAFull-Text 1670-1674
  Daiji Kobayashi; Sakae Yamamoto
It is difficult for human operator to control complex and large system by hand, because the delay of system response could be long. Although some previous studies characterized the progress in the manual control, the relation between the operator's progress and mental activity was not clear. In this study, we tried to make the relation clear and conducted a simulation experiment to compare the subject's performances and background electroencephalograms (EEGs). The EEGs were measured based on international 10-20 method while the subject controlled a target on the simulator. The subjects were 12 male students ranging from 19 to 23 years old. As the results, we found that the amplitude of theta waves at frontal region was getting higher when the subjects were under the unexpected condition.
The Effects of Relative System Reliability and Prioritization on Alarm Reaction Patterns BIBAFull-Text 1675-1679
  Elizabeth T. Newlin; Ernesto A. Bustamante; James P. Bliss; Randall D. Spain; Corey K. Fallon
Alarm system operators often manage multiple alarm systems concurrently. Because such situations often accompany cascading events, it is important to know how operators sequence responses. We examined how the relative reliability and priority of two concurrent alarms affected alarm gauge reset patterns. We hypothesized that operators would respond first to an alarm with higher reliability or higher priority when the other variable was held constant. We also expected participants to respond to alarms with higher priority first when they occurred at the same time as a high-reliability alarm. Sixty-one Old Dominion University undergraduates performed a tracking task and responded to gauge fluctuations (alarms). A between subjects ANOVA revealed that participants responded to alarms with higher priority first when reliability was constant, and to higher reliability alarms first when priority was constant. Our results suggest that relative priority and reliability may be useful parameters to control in complex task situations.

PERCEPTION AND PERFORMANCE: "In Touch" Vibrotactile/Haptic Symposium

A Symposium In Touch: Recent Developments in Tactile Applications BIBFull-Text 1680-1681
  Linda R. Elliott
Guiding Principles for Tactile Technology: Implications from Theory and Empirical Findings BIBAFull-Text 1682-1686
  Michael D. Coovert; Ashley A. Gray; Anna Tolentino; Nicole Jagusztyn; Fredrick R. B. Stilson; Rebecca H. Klein; Timothy J. Willis; Mike Rossi; Erin Jackson; Linda R. Elliott; Elizabeth S. Redden
There is an extensive literature on tactile interfaces and their overall importance to human-computer interaction is increasing. In this presentation we critically examine the psychological, computer science, engineering, and human factors literatures for tactile devices. Two major classes of principles emerge: those taken directly from authors' publications and those synthesized from the literature. Over 800 specific principles emerged from our work. We developed a structure for organizing the principles and offer the principles for specific guidance to researchers and practitioners.
Validation of Principles for Tactile Navigation Displays BIBAFull-Text 1687-1691
  Jan B. F. van Erp; Peter Werkhoven
Access to navigation information rapidly becomes standard in many situations, for example through GPS receivers and collision avoidance systems in cars. However, perceiving and processing the information may result in overloading the user's visual sense and cognitive resources. Intuitive navigation information presentation concepts using the sense of touch are claimed to be a solution to both threats. Employing the sense of touch can reduce the visual load, and the proverbial "tap-on-the-shoulder" may sheer automatically evoke the correct (control) behavior. This recently resulted in the development of car seats with vibrating elements, belts with vibrators for soldiers, tactile vests for pilots, and many similar displays. This paper presents a model for human behavior in platform navigation and control called prenav. Prenav allows discussing issues such as the accuracy of spatial information displays, effects on workload, and effects of external stressors. Prenav guided the validation studies we conducted in the last decade. Based on these studies, we concluded that tactile torso displays can potentially provide a major workload reduction and safety enhancement in platform control.
Tactile Technology for Covert Communications BIBAFull-Text 1692-1696
  J. Christopher Brill; Richard D. Gilson
The modern battlefield is an environment replete with information and distractions, often to the detriment of communication. To circumvent these issues, we developed TACTICS, a tactile display capable of covertly communicating directional cues and traditional U.S. Army Hand-Arm signals. A multi-pronged, human-centered approach was used to develop TACTICS, and specific considerations for general tactile display are discussed with TACTICS as an exemplar. Laboratory and field research suggest TACTICS is a highly effective means of communication by presenting tactile icons that are learned quickly, perceived intuitively, and discriminated successfully.
Findings from a Multi-Year Investigation of Tactile and Multi-Modal Displays BIBAFull-Text 1697-1700
  Elizabeth S. Redden
The U.S. Army's Advanced Technology Objective (ATO) titled "Situational Understanding as an Enabler for the Unit of Action Maneuver Team" sponsored a series of investigations to assess the utility of tactile displays, both as standalone displays and as part of multi-modal displays. The data from the ATO experiments demonstrated three areas in which tactile systems showed potential to increase soldier performance. These areas were communications in dismounted stealth operations, the use of multi-modal alerts (tactile paired with visual) during high visual workload periods, and reduction in visual tasks during extremely high workload.

PERCEPTION AND PERFORMANCE: Discrimination and Perception

The Effects of Aesthetic Attributes on Response Time and Aesthetic Judgement in a Multiattribute Binary Aesthetic Choice Task BIBAFull-Text 1701-1705
  Kristi E. Schmidt; Yili Liu
A systematic and quantitative study of aesthetics for both theoretical understanding and human factors application is needed to answer questions such as, "How do people make aesthetic judgements?" and "How do people perceive individual aesthetic attributes, and what effect does this perception have on performance?" This paper reports a binary aesthetic choice experiment whose objective was to examine the effect of the number of different aesthetic attributes on aesthetic perception of advertisements. A methodology is presented that quantitatively distinguishes displays based upon their individual aesthetic attributes and utilizes the performance measure of response time to examine the process of aesthetic judgment. Results show that when comparing two stimuli, an increased difference among aesthetic stimuli decreases processing and response time. Additionally, there is a limit in the number of different attributes participants consider when making aesthetic judgments.
The Effects of Transient Emotional State and Workload on Size Scaling in Perspective Displays BIBAFull-Text 1706-1710
  Tuan Q. Tran; Kimberly R. Raddatz
Previous research has been devoted to the study of perceptual (e.g., number of depth cues) and cognitive (e.g., instructional set) factors that influence veridical size perception in perspective displays. However, considering that perspective displays have utility in high workload environments that often induce high arousal (e.g., aircraft cockpits), the present study sought to examine the effect of observers' emotional state on the ability to perceive and judge veridical size. Within a dual-task paradigm, observers' ability to make accurate size judgments was examined under conditions of induced emotional state (positive, negative, neutral) and high and low workload. Results showed that participants in both positive and negative induced emotional states were slower to make accurate size judgements than those not under induced emotional arousal. Results suggest that emotional state is an important factor that influences visual performance on perspective displays and is worthy of further study.
A More Parsimonious Approach to Estimating Signal Detection Theory Measures BIBAFull-Text 1711-1715
  Ernesto A. Bustamante; Corey K. Fallon; James P. Bliss
Signal Detection Theory (SDT) has proven to be an effective tool for analyzing perceptual and decision-making performance in many different areas. The main contribution of SDT is its capability to separate the discrimination process from the decision process by distinguishing between measures of sensitivity and measures of response bias. However, the usefulness of the traditional SDT measures of sensitivity, d', and response bias, c, is questionable in applied settings where observers do not make decisions based on an underlying psychophysical continuum. The purpose of our research was to derive alternative measures of sensitivity and response bias, overcoming the limitations of the traditional SDT model. Results from a Monte Carlo simulation showed support for our more parsimonious model.
Application of Fuzzy Signal Detection Theory to the Discrimination of Morphed Tank Images BIBAFull-Text 1716-1720
  J. L. Szalma; T. Oron-Gilad; B. Saxton; P. A. Hancock
The effect of response set size on performance on a detection task was evaluated using both fuzzy and traditional signal detection theory. Fuzzy categories of stimuli were created using morphing software to blend profile images of American (M1A1) and Iraqi (T55) tanks to different degrees. These combinations were used to create static images varying from 100% T55 to 0% T55 (100% MIA1). Participants were asked to indicate the degree to which each image did not resemble an American tank. Consistent with previous research, results indicated that the FSDT model conforms to the normality assumption of traditional SDT. In addition, forcing observers to make binary decisions impaired performance relative to multi-category response sets in the FSDT analysis but not the traditional analysis. However, there were more model convergence failures in the FSDT analysis relative to the traditional analysis, mostly associated with conditions in which there were 100 response categories.
Comparing Estimated and Actual Visual Acuity at High and Low Luminance BIBAFull-Text 1721-1725
  Johnell O. Brooks; Richard A. Tyrrell; Benjamin R. Stephens
How much insight do individuals have into their own visual abilities? This study investigated the extent to which individuals from 18 to 78 years old can accurately predict their own acuity under a broad range of luminances. New Psychophysically based methods were developed to facilitate direct comparisons between individuals' estimates of their own visual acuity and their actual acuity. While all age groups appreciate that reductions in luminance have negative consequences on acuity, both younger and middle-age adults underestimated their ability to see in dim conditions. Older adults, however, overestimated their ability to see. These results fail to support the hypothesis that seniors would be the most aware of their limited visual abilities at night. Future research should explore why some seniors are comfortable driving at night while others are not.

POSTERS: POS1 - Posters

The Relationship between Dimensions of Personality and Situational Awareness in a Navigation Simulator BIBAFull-Text 1726-1730
  Evelyn-Rose Saus; Bjorn Helge Johnsen; Jarle Eid
The aim of the present study was to explore the relationship between personality and situational awareness (SA). 34 first year students from The Royal Norwegian Navy Officer Candidate School participated in this study. SA was measured during training in the navigation simulator at the Royal Norwegian Naval Academy. Both subjective and observer ratings of SA was measured using the Situational Awareness Rating Scale (SARS). Personality was measured using The NEO Personality Inventory (NEO PI-R). The results indicated that neuroticism was negatively related to both subjective and observer SA. Extroversion and conscientiousness were positively related to subjective SA. Regression analyses showed that the dimension of conscientiousness with the facet competence could predict subjective SA, and the dimension of neuroticism predicted observer ratings of SA.
Short Stress State Questionnaire: Relationships with Reading Comprehension and Land Navigation BIBAFull-Text 1731-1735
  William S. Helton; Gregory Garland
Stress is an important aspect of operational settings. This article presents the results of a study providing further validation evidence of a short multidimensional self-report measure of stress-state, the Short Stress State Questionnaire (SSSQ; Helton, 2004). We investigated stress changes in two settings. In the first setting, we explored the relationship between the SSSQ and reading comprehension. In the second setting, we explored the relationship between the SSSQ and a real world land navigation task - orienteering. Different task conditions elicited unique patterns of stress-state on the three factors of the SSSQ. Additionally, unique aspects of stress-state were predictive of performance on the two tasks. The 24-item SSSQ appears to be a useful measure of stress-state applicable in a wide variety of settings, including field settings.
A Meta-Analysis of Performance Under Thermal Stress BIBAFull-Text 1736-1740
  Jennifer M. Ross; James L. Szalma; Peter A. Hancock
The goal of this work was to perform a quantitative review of temperature effects on human performance, with the aim of advancing both theory and practice. Meta-analytic methods were applied to the available literature on thermal stress and performance. Two-hundred-ninety-one references were collected resulting in forty-nine publications that met selection criteria. These studies provided 528 effect sizes. Analyses revealed an overall detrimental effect of temperature on performance. Effect-size for heat was comparable to that for cold temperatures. Temperature effects were task dependent, that is cognitive performance was least affected by thermal stress, while both psychomotor and perceptual task performance were degraded to a greater degree. Other moderating variables were identified and observed to influence the effect of thermal stress. Although the results clearly indicate more empirical research is necessary to achieve more accurate estimates, the current study provides initial effect-size estimates that should be considered when designing human-machine systems.
The Effects of Whole-Body Vibration on Human Performance: A Meta-Analytic Examination BIBAFull-Text 1741-1745
  G. E. Conway; J. L. Szalma; B. M. Saxton; J. M. Ross; P. A. Hancock
Whole-body vibration exerts a substantive influence in many work environments. The primary objective of the present paper was to ascertain the effect of whole-body vibration and identify those moderating variables that influence the degree to which human performance is affected. A comprehensive meta-analysis was conducted which quantified the existing research evidence. Following a screening process of the collected literature, a total of 224 papers and reports were identified for analysis. From these papers, 115 effect sizes were derived from 13 experiments which survived the screening procedure. Results indicate that vibration acts to degrade the majority of goal-related activities, especially those that rely on visual perception and fine motor control. Gaps in the extant research literature are identified and suggestions offered with regard to a more theoretically-driven approach to testing stressor effects on human performance.
Effects of Handwear and Hand Posture on Four Performance Measures in Foil Fencing BIBAFull-Text 1746-1750
  Kai Way Li; Chih-Lin Chang
In foil fencing, an adequate amount of hand forces and dexterity is extremely important in manipulating the foil and thus affecting the performance of a fencer. The purpose of this study was to investigate the effects of handwear of fencing gloves and posture on four performance measures in foil fencing. Eight male fencers were tested in an experiment. Four measures of fencing performance were collected and analyzed. They were the grip and pinch forces under four hand postures and the hitting scores and motion time under a fundamental attacking scenario. Analysis of variance was conducted. Duncan's multiple range tests were conducted if a significance level of 0.05 was reached. The results showed that both the handwear condition and posture were significant on the grip force. The effects of posture on grip and pinch forces were both significant. Handwear affected hitting accuracy significantly. The effect of handwear on pinch force was not significant. The hitting scores for both the glove I and II conditions were significantly higher than the bare hand condition. The results in this study supported that selection of the thinnest glove resulted in relatively better performance for the fencers.
Using Discrete Event Simulation to Assess Human Lifting and Assembly of Vehicle Armor BIBAFull-Text 1751-1754
  Beth Plott
The Future Combat Systems (FCS) program goal is to develop the next generation of vehicles and networks for the Army. Eight configurations of Manned Ground Vehicles (MGV) are being designed as part of this effort. Requirements state that each MGV must weight less than 20 Tons to be C-130 transportable. To achieve this weight limitation the armor will be removed before flight. The armor will be flown in on a separate aircraft and installed at the destination. A specific challenge for the manufacturer of the MGVs is determining how best to utilize human resources in the installation process. This poster will describe the use of discrete event simulation to develop a human performance model that helps determine an optimal combination of manpower, armor panels, and installation equipment. Four different "up-armor" scenarios were simulated each with different manpower, number of armor pieces, size of armor pieces, and material handling equipment requirements.
Back Extensor Muscle Oxygenation and Blood Volume Comparisons During two Endurance Exercise Modes BIBAFull-Text 1755-1758
  Rammohan V. Maikala; Yagesh N. Bhambhani
Since the current near-infrared spectroscopy devices do not measure absolute muscle saturation, normalization of hemodynamic measurements by occluding blood flow to muscles is considered acceptable. However, physiological reference for the paraspinal muscles is difficult with occlusion techniques. This study compared muscle oxygenation and blood volume responses in healthy men and women during: static back muscle endurance test (SBME) and stepwise incremental repetitive pushing-pulling exercise (PP). On two separate days, subjects completed SBME and PP until volitional exhaustion. Both oxygenation and blood volume values were obtained from the right erector spinae muscle. At volitional exhaustion, PP resulted in greater deoxygenation than during SBME (P<0.05). However, physiological change observed (calculated as the difference between the maximum and minimum values for oxygenation and blood volume) was not significantly different between exercise models in both genders, suggesting either endurance exercise modes can be used interchangeably to establish physiological limits for the lumbar muscle.
Individual Differences in Concurrent Performance of Gunner's and Robotic Operator's Tasks BIBAFull-Text 1759-1763
  Jessie Y. C. Chen; Carla T. Joyner
In this study, we simulated a military mounted environment and conducted an experiment to examine the workload and performance of the combined position of gunner and robotic operator and how individual difference factors such as perceived attentional control and spatial ability were related to the task performance. Results showed that gunner's target detection performance degraded significantly when he or she had to concurrently monitor, manage, or teleoperate an unmanned ground vehicle compared to the gunnery-single task condition. Those with higher spatial ability performed significantly better than those with lower spatial ability. Participants with higher perceived attentional control performed better on a concurrent communication task in the more challenging robotic task conditions. Participants' perceived attentional control was negatively correlated with the severity of their simulator sickness but not with their perceived workload.
A Comparison of Two Mental Workload Instruments in Multimedia Instruction BIBAFull-Text 1764-1768
  David Windell; Eric Wiebe; Sharolyn Converse-Lane; Barry Beith
Cognitive Load Theory focuses on several assessment techniques to assess overall cognitive load, including its three-subclasses, and its relationship to learning. Methods include psychophysical and secondary task techniques, along with task performance and self-report. The current study looks to review two popular self-report measures (NASA Task Load indeX, and a short subjective instrument) and identify not only if they are consistent with one another, but also to discover whether both are equally sensitive across changes in levels of cognitive load subclasses. The two subclasses looked at in this study are intrinsic load, which is related to element interactivity, and extraneous load, which is influenced by the instructional design itself. Results from this study indicate that the NASA-Task Load index, as a weighted multi-dimensional rating scale, differs in measurement of the demands faced by learners in a PC-based, multimedia-learning environment from the more traditional, single-questions short subjective instrument.
Team Response to Workload Transition: The Role of Team Structure BIBAFull-Text 1769-1773
  M.-E. Jobidon; R. Breton; R. Rousseau; S. Tremblay
The present study aims to investigate how teams respond to workload transition due to a sudden and unexpected event in a complex and dynamic command and control (C2) environment. The C3Fire microworld (Granlund, 1998), a forest firefighting simulation, is used to compare divisional (territory-specific) and functional (role-specific) teams. Workload transition is induced by the sudden appearance of a second fire. Results show that functional teams' performance decreases while their communication frequency increases following the workload transition. However, they are faster to detect the second fire. This pattern of results suggests that in the context of C2 environments, the impact of a workload escalation varies as a function of team structure (functional vs. divisional) and the type of task (fire detection vs. fire fighting).
Cultural Evolution in Team Problem Solving BIBAFull-Text 1774-1778
  Michael A. Rosen; Stephen M. Fiore; Eduardo Salas
This paper uses a framework developed from memetics -- a theoretical perspective on cultural evolution -- as the basis for investigating aspects of team problem solving. Specifically, the roles of shared mental models, team situational awareness, and team problem models in the problem identification and conceptualization stages of team problem solving are explored from a cultural evolutionary perspective. Results of this analysis indicate that cultural evolutionary perspectives are useful in interpreting developmental aspects of team problem solving skills and adaptations of team level knowledge to task and environmental constraints.
Social Influence in a Distributed Simulation BIBAFull-Text 1779-1783
  Kevin B. Oden; Peter Terrence; Jeff Stahl
Massively multiplayer environments provide a distributed simulation in which to assess the effects of social influence on individual behaviors. This study used this platform to determine the presence of conformity within a virtual environment, essentially replicating the classic social psychology methodology employed by Asch (see Asch 1952a, 1956) on conformity of responses to perceptual judgment tasks. Experimental confederates acting as users in a distributed simulation provided unanimously incorrect responses to a simple line judgment task. Actual experimental participants varyingly demonstrated conforming behavior in their responses, with some deviations from Asch's findings. Implications for training, particularly in military settings, are discussed as are necessary future research endeavors.
Linguistic Analysis is Useful in Predicting Group Brainstorming Performance BIBAFull-Text 1784-1788
  Mary T. Dzindolet; Linda G. Pierce
Interactive brainstorming groups generate fewer ideas than the combined output of the same number of members working individually (cf., Mullen, Johnson, & Salas, 1991). However, even armed with this information, businesses and organizations often use groups to generate ideas. Being able to identify groups that brainstorm well would be beneficial to businesses and organizations. The transcripts of brainstorming groups from six separate studies were examined and results indicated that linguistic analysis, specifically, the Linguistic Inquiry Word Count (LIWC), is useful in identifying high performing brainstorming groups. The more group members avoided the use of first person pronouns, negate words, inclusive and exclusive words, and discussions of cognitive and social mechanisms, the more ideas the groups tended to generate. The fact that the pattern appeared across studies that included brainstorming groups of differing size, working on different problems at different locations speaks to the generalizability of the finding.
Change Blindness in Teams: Are Three Pairs of Eyes Better than One BIBAFull-Text 1789-1793
  Alison M. Tollner; Michael A. Riley; W. Todd Nelson; Kevin D. Shockley; Sarah Cummins-Sebree
Several studies have indicted that people often fail to detect changes in visual displays under a variety of conditions. More recent research has indicated that individual operators are susceptible to change blindness in military command and control environments. Change blindness has been studied extensively but only at the individual level. Very little research has explored change blindness in the context of team performance. The purpose of this experiment was to determine if teams were more or less susceptible to change blindness than individual observers in the context of a simulated military command and control situation display. Individuals and teams monitored flicker sequences of displays containing 6, 12, 24, or 48 icons for changes in icon position. Our results revealed a team advantage but this effect was more pronounced when teams communicated. Communicating teams outperformed both non-communicating teams and individuals. However, communicating teams were not immune to change blindness but team communication played a key role in reducing change blindness and the workload associated with the change detection task.
Fifty Years of Warning Researchers BIBAFull-Text 1794-1797
  T. J. Ayres
This paper attempts to trace the history of empirical research on warning labels and signs, with particular emphasis on work within the HFES. Observations are made about the focus and methods that have been used, highlighting considerable progress as well as continuing problems. The approach typically taken in work presented to the HFES is compared with safety communication research reported in other disciplines, and suggestions are made for future directions.
Trends in Consumer Product Warnings Found in Voluntary Standards BIBAFull-Text 1798-1802
  Christine Wood; Joseph B. Sala; Katherine Sanders; Paul Cassidy
Consumer products available today in the United States often have safety information on and accompanying them. This practice is far more common now than earlier in the 20th century. In this paper, the evolution of the use of warnings with consumer products is examined as they appeared in voluntary standards provided by one national standard making body, the American Society for Testing and Materials (ASTM). ASTM had been developing consensus voluntary standards since 1898, but it was not until the 1970s that it first focused on consumer products. Over the next three decades there were increases in the number and type of consumer products included. Further, for any given product, the amount of safety information frequently increased with subsequent revisions of a standard. These trends in warnings generally parallel the patterns observed with federally mandated warnings for consumer products.
Update on Ansi Z535.6: A New Standard for Safety Information in Product Manuals, Instructions, and Other Collateral Materials BIBAFull-Text 1803
  Steven M. Hall
A new standard, ANSI Z535.6, Product Safety Information in Product Manuals, Instructions, and Other Collateral Materials, is scheduled to be published in 2006. The standard provides requirements for the format and presentation of safety messages in a variety of product publications. This poster session will illustrate the format requirements and a variety of particular formats that conform to the standard. This will educate those who are not familiar with the standard about its existence and requirements. It will also assist practitioners who are familiar with the standard by illustrating a variety of ways to implement the requirements of the standard.
Realistic Capacity Limits for Marine Passenger Safety: Adult Body Weight Distributions in the United States BIBAFull-Text 1804-1807
  Claire C. Gordon
Transportation and lift systems usually incorporate maximum capacity specifications for design, testing, and operation. Whether maximum capacity is specified directly in kilograms, or indirectly as maximum number of adults, user safety depends on accurate and logical relationships between system specifications and the upper limits of body weight distributions in the user population. This study utilizes recent data from the National Health and Nutrition Examination Survey (NHANES) and bootstrap methodology to establish meaningful weight capacity limits for small (10 person) marine craft, concluding that the average adult weight of 75 kg used to establish capacity limits for small marine craft in several ISO standards is far too low to represent contemporary US adults. This study indicates that a randomly selected group of 10 adult males will exceed the 750 kg capacity 97.6% of the time, and a group of 5 adult males and 5 adult females will exceed the 750 kg capacity 80.1% of the time. In fact, this study suggests that a design and testing assumption of 97.5 kg per adult (975 kg for 10 people) is needed to ensure that groups of 10 adult males (the worst case for small craft design) are within capacity limits 95% of the time.
Psychometric Survey Methods for Measuring Attitudes Toward Homeland Security Systems and Personal Privacy BIBAFull-Text 1808-1811
  Thomas F. Sanquist; Heidi A. Mahy; Christian Posse; Frederic Morris
A survey method for measuring attitudes regarding homeland security systems and personal privacy is described. By use of a simple rating scale method and factor analysis, insight can be gained regarding various technologies and the reasons people consider them more or less acceptable in terms of privacy issues.

POSTERS: POS2 - Posters

User Password Generation Practices and Strong Password Guideline Compliance BIBAFull-Text 1812-1816
  Shannon Riley; Barbara S. Chaparro
This study investigated the common password generation practices of online users. Three hundred and fifteen undergraduate and graduate college-age students completed a survey querying; internet usage demographics; the types and number of different password protected accounts maintained; actual practices used in generating, storing and using passwords; what practices users believe that they should use in generating and storing passwords; and general demographic information. Results indicate that, in general, users do not vary the complexity of passwords depending on the nature of the site or change their passwords on a regular basis if not required by the site. In generating passwords users typically report using (1) lower case letters, (2) numbers or digits, (3) personally meaningful numbers and (4) personally meaningful words.
I Downloaded What?: An Examination of Computer Security Decisions BIBAFull-Text 1817-1820
  Jefferson B. Hardee; Christopher B. Mayhorn; Ryan West
Computer users are faced with seemingly minor security decisions on a daily basis. While much is known about decision-making in general, less is known about decision-making in the context of computer security. In the current experiment, 56 relatively knowledgeable computer users completed a decision-making task that included 24 scenarios which varied in terms of decision domain (computer vs. non-computer), risk (high vs. low), and gain-to-loss ratio (high gains/low losses, equal gains/losses, low gains/high losses). Results indicated that there was no difference between computer and non-computer decisions when risk and gain-to-loss ratio were held constant. However, these decision factors did interact to differentially influence decisions within each of these domains. Perception of risk greatly impacted computer decisions whereas the gain-to-loss ratio seemed to have a larger influence on the non-computer decisions. Potential directions for computer security software design, user training, and future research are discussed.
How Tidy Is Your Desktop A Field Study of Organizational Strategies BIBAFull-Text 1821-1824
  G. Megan Payton; Carol T. Hurn; C. Melody Carswell; Shawna M. Webb
Do most office workers customize the absolute or relative locations of icons on their computer desktops in an effort to enhance personal efficiency? Eighty-three employees in a variety of office settings allowed us to document the layout of their desktops and then took part in semi-structured interviews. Just under half of our participants (49%) repositioned their icons from the default locations generated by their computers' operating systems. Only 9% reported grouping icons by function. When the strategies of workers who considered their desktops organized were compared to those who did not, the most notable (and only reliable) distinction was the lower absolute number of icons on the "organized" desktops. Our participants' mostly passive approach to customization may have implications for the use of adaptive versus adaptable interfaces, and it demonstrates the need for decisional guidance tools to support even simple customization.
Comparison of Three Avionics Systems Based Upon Information Availability, Priorities and Accessibility BIBAFull-Text 1825-1828
  Christopher J. Hamblin; Cindy Miller; Shiva Naidu
This study evaluates three avionics systems typically found in small general aviation aircraft. The evaluation included a traditional "steam gauge" airplane, an "intermediate" airplane equipped with traditional mechanical instruments along with a GPS-based moving map display and a technically advanced airplane equipped with a computer-based glass cockpit. We evaluated the avionics using a methodology described by Schvanevelt, Berringer & Leard (2004) which evaluates the availability and accessibility of information based upon the priorities pilots place upon the various information sources. The results show that computer-based avionics provide more information; however most of the additional information is located deep within the avionics' menu structure.
The Legibility of ClearType Fonts BIBAFull-Text 1829-1833
  Barbara S. Chaparro; A. Dawn Shaikh; Alex Chaparro
This article introduces six new ClearType fonts (Cambria, Constantia, Corbel, Candara, Calibri, and Consolas) developed by Microsoft. Legibility of the font lowercase letters, digits, and symbols was compared to two traditional fonts, Times New Roman and Verdana. Results show that the legibility, as measured by the number of correct identifications of briefly presented characters, was highest for the new fonts Consolas and Cambria, and lowest for Candara and Corbel. Old style numerals, such as 0,1, and 2, used in Constantia, Candara, and Corbel resulted in confusion with the letters o, 1, and z. Several symbols in Times New Roman were confused with both letters and other symbols.
Personality of ClearType Fonts BIBAFull-Text 1834-1838
  A. Dawn Shaikh; Barbara S. Chaparro; Doug Fox
Substantial research regarding typeface persona has not been conducted for onscreen media. Previous research indicates that printed typefaces have associated personas and have the potential to create meanings that extend beyond the printed text. This study examined six new ClearType fonts and six existing fonts representing serif, sans serif, and monospaced font groups. Fonts were examined using 15 personality pairs through an online survey. Results indicated that serif fonts were characterized as more traditional in personality; sans serif fonts were perceived as more casual; and monospaced fonts were described as plain and dull. Overall, this study makes an initial attempt to establish perceived onscreen personas common fonts while evaluating the newest Microsoft fonts.
Usability Evaluation of Digital Flipviewer Online Flipbooks BIBAFull-Text 1839-1843
  Spring S. Hull; Barbara S. Chaparro
The rise in onscreen reading has created a need for software products that allow users to comfortably view documents onscreen. Two studies were conducted to examine the usability of E-Book Systems Digital FlipViewer software that enables users to read FlipBooks, interactive three-dimensional books with pages that 'flip' or turn onscreen. Study 1 evaluated user performance on completing eleven tasks with the FlipViewer using a magazine format. Study 2 evaluated user performance of finding courses using a FlipBook format of a university's schedule of courses. Results from Study 1 revealed participants had difficulty using the unique features of FlipViewer, but overall, were satisfied with their experience viewing a document in this format. Results of Study 2 showed participants completed tasks quicker using the FlipBook format of the university course schedule when compared to a website format.
Improving Website Usability with Latent Semantic Analysis BIBAFull-Text 1844-1848
  Sarah A. Nuehring; Peter W. Foltz
When people search for information on the Web, they rely on link descriptions to decide where to look. If the descriptions are not sufficiently accurate, people will have a hard time navigating. This difficulty is what is known as the vocabulary problem. The overall goal of this study was to develop a way of making the vocabulary problem less probable on websites: first by improving the information scent of links in websites, and second by investigating the relationship between information scent and website navigability. Information scent was defined as the semantic similarity between a link description and its target information, quantified using Latent Semantic Analysis (LSA). Lists of keywords related to web pages were obtained from human participants and from LSA, and then the keywords were used to make modifications to the links on web pages. Participants showed faster navigation when using the modified websites compared to using the original websites.
Effects of Eye Structure and Color on Attributions for Intelligent Agents BIBAFull-Text 1849-1852
  Valerie K. Sims; Matthew G. Chin; Hana S. Smith; Tatiana Ballion; David J. Sushil; Michael Strand; Sarah Mendoza; Randall Shumaker; Neal Finkelstein
Participants rated machine "faces" which varied in terms of facial feature shape, whether the eyes had a pupil or not, and seven eye colors (blue, green, orange, pink, red, purple, or yellow). Ratings were made for aggression, friendliness, intelligence, trustworthiness, and degree of animation. Faces with eyes that had a discernable pupil were rated most positively, as were those with round features, suggesting that minimal features that evoke "humanness" are important for establishing trust. When eyes contained red, however, faces were rated much more negatively. Color schemas appear to override anthropomorphic schemas of humanness when conflicting cues are present. Implications for the design of intelligent agents are discussed.
Designing an Intelligent Agent Vertical and Horizontal Features Activate Different Face Schemas BIBAFull-Text 1853-1857
  Valerie K. Sims; Matthew G. Chin; Tatiana Ballion; David J. Sushil; Hana S. Smith; Bryan Clark; Randall Shumaker; Neal Finkelstein
Participants rated machine "faces" which varied in terms of color scheme (white on black or black on white), feature shape (round or square), verticality of eyes, verticality of nose, and verticality of mouth. Ratings were made for aggression, friendliness, intelligence, trustworthiness, and attractiveness. Equally proportioned features yielded the most positive ratings, but all features were important in predicting the magnitude of the difference. Trustworthiness ratings appeared to require the most complex facial processing. Design of intelligent agents needs to take into account the minimal features that elicit an anthropomorphic response.
Crewmember Trust in the Trident Submarine Internal Communication Subsystems During Normal and Emergency Operating Conditions BIBAFull-Text 1858-1861
  Michael C. Mihalecz; William R. Bailey; Ernesto A. Bustamante
Submarine internal communications subsystems vary widely in their design and capabilities. As a result, submarine crews may feel that internal communications differ in reliability and place associated levels of trust in them, especially during emergency operating conditions. We examined a US Navy Trident submarine crew as they used the internal communications subsystems during a four-day period at sea. The results showed that crewmembers' level of trust in the submarine's internal communications subsystems was significantly reduced during emergency operating conditions. Specifically, we noted that the submarine's wire free communication system as well as its sound powered phone systems received the lowest trust ratings. Interviews conducted with the crewmembers revealed several problems associated with these types of communication subsystems. The most often cited problems included poor durability, maintainability, effective range, battery life, freedom of movement, and sound quality. Designers should address these problems to improve crewmembers' reliability and trust in future internal communication systems.
Taxonomy of Group Chat: A Basis for Understanding and Design BIBAFull-Text 1862-1865
  Jennifer Ockerman; Nathan Koterba
Instant messaging, or online chat, has existed for almost a decade. Today, more individuals are using chat in the work place as organizations increasingly acknowledge chat as a useful collaborative tool, particularly in distributed work environments. One organization where chat has seen overwhelming adoption is the military. Chat is ideally suited for military domains as it consumes low-bandwidth and provides nearly synchronous communication. In addition, military chat users can simultaneously monitor multiple group conversations, making chat an important situation awareness tool. Despite its extensive use, little research exists on chat use in the workplace, particularly the military, and almost none is devoted to making the chat environment more attuned to user needs. Before extensive studies on and possible improvements to chat environments can occur, an understanding of the different chat environments is needed. This paper provides an initial classification scheme for different types of chat.
A Novel Approach to Bridging the Gap Between Cognitive Engineers and Software System Engineers BIBAFull-Text 1867-1871
  Adam Fouse; Jonathan Pfautz
To aid the development and deployment of complex software systems, techniques are needed to ensure effective communication between human factors and cognitive engineers, the software system engineers, and other stakeholders (e.g., users of the system under development, project managers). In this paper, we present a novel approach to addressing this need. Our approach is based on the view that systems development is a holistic process and that human factors and cognitive engineering can best be integrated as a component of that process, rather than explicitly altering the systems engineering process to incorporate human factors and cognitive engineering. We describe this approach in more detail, and present a tool that embodies this approach by facilitating communication among stakeholders by leveraging existing software tools used in systems development.
The Resource for Applied Cognitive and Systems Engineering (Trace-Se): An Approach to Understanding the Gap BIBAFull-Text 1872-1876
  Heather A. Stoner; Emily M. Stelzer; Emily E. Wiese; Michael Paley; Adam Darowski; Gilbert Mizrahi; Edward A. Martin
Today's workplaces are complex organizations in which people connect to information, people, and the world through advanced technology. Accordingly, the nature of work evolves as the workplace adds technologies that challenge traditional skills and increase demands for highly specialized cognitive skills. Systems must therefore be designed to account for the cognitive strengths and limitations of users and support decision-based operations. Traditional systems engineering practices, however, frequently fail to expressly consider cognitive factors in design or consider them belatedly in the design cycle. As a result, systems are often designed that do not fully leverage the cognitive strengths of the human user or compensate for their limitations. Yet, embedding cognitive engineering methods into established systems engineering processes can be complex and expensive without tools to structure and support it. The Resource for Applied Cognitive Engineering and Systems Engineering (TRACE-SE) is a prototype web-based tool that can be used to begin bridging the gap that exists between cognitive and systems engineering. TRACE-SE provides the information needed to simultaneously support both cognitive and systems engineers in the design of user-centered systems that can produce superior decision making, improved safety, and greater operator productivity.
A Theoretical Framework of a Bionomic Approach to Improve Individual and Organizational Outcomes BIBAFull-Text 1877-1881
  Lauriann M. Jones; Mustapha Mouloua
Human Factors often attempts to combat the effects of stress on human productivity through such tools as, automation, ergonomics, and training in the workplace but traditional human factors routes may not always be sufficient. Some organizations (e.g., military and civilian) may always suffer some degree of stress which may inadvertently disturb personal individual outcomes and resultant organizational outcomes, traditionally of macroergonomic concern. Positive bionomic effects on humans are well documented in other fields and being introduced here for consideration as a viable resource, possibly supplement, to traditional human factors/macroergonomic tools. Two models of this bionomic theory for human factors applications are presented for improving individual and organizational, physical, psychological, and social outcomes.
The Effect of Two Office Ergonomics Field Interventions and Their Replication on Visual Symptoms BIBAFull-Text 1882-1886
  Cammie Chaumont Menendez; Michelle Robertson; Benjamin C. Amick; Ronald B. Harrist; Lianna Bazzani; Kelly DeRango; Anne Moore
Upper extremity musculoskeletal symptoms and disorders in the workplace continue to be a significant public health burden (National Research Council and Institute of Medicine, 2001). These outcomes, as they relate to computer use, are important as greater than 50% of employed adults in the United States use a computer at work (U.S. Census Bureau, 2003). Visual symptoms are also known to often coexist with upper extremity musculoskeletal symptoms with computer workers. This study examines the effect of two office ergonomic interventions, a highly adjustable chair and an office ergonomics training, on the reduction of specific visual symptoms. Additionally, findings from a replicated study site are compared with those of the original study. Multilevel logistic regression models were used to estimate the effect. In comparing the original and replication worksites we find specific visual symptom reductions occurred for the group receiving both the chair with training at the original and replicated worksite. However, the group receiving only the office ergonomics training experienced individual visual symptom reductions at the replication worksite but not the original worksite. There were differences in the specific visual symptoms affected by the office ergonomics interventions when comparing worksites.
Subjective Perceptions Toward Selected Power Nutrunner Torque Reactions BIBAFull-Text 1887-1891
  Jia-Hua Lin; Raymond W. McGorry
Power hand tools have the potential to produce reaction forces that may be associated with upper extremity musculoskeletal disorders (UEMSDs). The reaction forces affect the subjective ratings of perceived exertions associated with tool operations. This paper addresses how operators perceived power nutrunner torque reactions. Two work configurations using pistol grip and right angle tools were tested in the laboratory. Twenty male participants operated four automatic shutoff pneumatic nutrunners on two different task joints using various postures. Handle displacement and the grip force for each torque reaction was monitored. Subjective ratings of discomfort and acceptance toward the given reaction were recorded. The results show that discomfort and acceptance for torque reactions were significantly affected by grip force but not by handle displacement. Odds ratios using grip force as a predictor were calculated. This study can helping setting physical exposure limits encountered in power nutrunner operations.
Residential Wall Panel Designers Knowledge and Attitudes Toward Ergonomics BIBAFull-Text 1892-1896
  Sunwook Kim; Michael J. Hurley; Maury A. Nussbaum; Laura E. Hughes; Kari L. Babski-Reeves
There is increasing use of panelized (prefabricated) wall systems in residential construction, requiring construction workers to handle larger and heavier components. Panel designers can make a substantial impact on ergonomic exposures of on site workers if ergonomics is considered in the design phase. A survey and a semi-structured interview were conducted to assess current knowledge and opinions of ergonomics among panel designers. Twelve panel designers from 11 different panel companies participated in the study. Results of the survey and the interview suggested that panel designers are rather resistant to the inclusion of ergonomics in their design, and they generally lack training in ergonomics. Designers considered themselves least responsible for construction worker safety and health, likely because they are disconnected from on site workers. Thus, it is essential that panel designers are supported with ergonomic assessment tools that can evaluate ergonomic exposures and provide alternative (improved) designs.

POSTERS: POS3 - Posters

A Human Factors Analysis of Cardiopulmonary Bypass Machines and Associated Components and Procedures BIBAFull-Text 1897-1900
  Thomas Suther; Douglas Wiegmann; Thoralf Sundt; Brent Phillips
Cardiopulmonary bypass machines (CBM's), first developed in 1953, are commonly used during heart surgery to oxygenate blood and circulate it throughout the body while the heart is stopped. Although several advances have occurred in the engineering of perfusion pumps, the interface design of CBM's has not changed appreciably for several decades. The growing awareness of human error in medicine has highlighted the role that poorly designed medical devices can play in producing errors that cause patient harm. The purpose of this study, therefore, was to identify issues related to CBM design that may predispose surgical teams to make errors. The study utilized multiple research methods including observations, heuristic evaluations, structured interviews and usability assessments. Results revealed several fundamental design problems associated CBM displays, controls, alarms, and component integration, as well as communication and procedural issues. These data provide valuable information for redesigning CBM's to reduce errors and improve patient safety.
The Aperture Illusion Can Occur with 3-D Displays and Active Control: Implications for Minimally-Invasive Surgery BIBAFull-Text 1901-1904
  Tammy E. Ott; Patricia R. DeLucia
When a moving contour is viewed through a circular aperture, observers misperceive the contour's direction of motion. This aperture illusion is relevant to minimally-invasive surgery because surgeons view anatomical tissues through a reduced field-of-view. In prior studies of the illusion, observers passively viewed simple computer-generated displays of moving lines. Here, it is demonstrated that the illusion can occur with displays created with a 3-D laparoscopic simulator, and when participants actively control the movement of a surgical grasper. However, the illusion was smaller with active control than with passive viewing, and was smaller with a rectangular aperture than with a circle or octagon. The implication is that navigation during MIS may improve when surgeons (rather than assistants) actively control the camera, and when the aperture that frames the laparoscopic image is rectangular. Future studies of this kind will improve the design of image-guided technologies and reduce complications during MIS.
Does Active Control Eliminate the Aperture Illusion BIBAFull-Text 1905-1909
  Tammy E. Ott; Patricia R. DeLucia
When a contour moves behind a circular aperture, observers misperceive the contour's motion as perpendicular to its orientation regardless of its true motion. This aperture illusion is relevant to the design of technologies that limit an observer's field of view, for example, cameras used in minimally-invasive surgery. Thus, it is important to determine the conditions under which the illusion occurs and how to eliminate it. In prior studies of the aperture illusion, observers passively viewed displays in which a line moved behind an aperture. Here, we demonstrated that the illusion occurred when participants actively controlled the line's motion. Furthermore, the aperture illusion was smaller with a rectangular aperture compared with a circle or octagon. Further research of this kind will help improve the design of technologies that limit an observer's field of view.
Time Estimation as a Measure of Mental Workload During the Training of Laparoscopic Skills BIBAFull-Text 1910-1913
  Cindy H. Lio; Kyle Bailey; C. Melody Carswell; W. Brent Seales; Duncan Clarke; G. Megan Payton
How sensitive are distortions in students' time perception to changes in demand across laparoscopic training tasks? Volunteers used an endoscopy training simulator to perform two common training tasks. The simpler of the two tasks involved using graspers to move beads from a dish to a small bucket. The more difficult task involved threading beads onto small pegs. In one experiment, 13 participants estimated the duration of each training trial immediately upon its completion. They also completed the NASA-TLX. In another experiment, 15 participants verbally indicated when they thought each successive 31-second interval had elapsed while performing the training trials. Results indicated that errors in temporal judgments were sensitive to differences in task demand using the interval production method but not the retrospective estimation technique. One implication is that interval production shows promise as a secondary task workload measure for laparoscopic tasks, although procedural refinements are needed to maximize the measure's sensitivity.
Talk is Cheap: On the Usability Advice Salespeople Offer to Older Consumers BIBAFull-Text 1914-1916
  Andra Bush; C. Melody Carswell; Michelle Corman; Miranda Briscoe; Cindy H. Lio
When older consumers approach a salesperson with questions about product usability, what advice are they likely to receive? To find out, we interviewed salespeople selling four types of products - cell phones, dryers, recliners, and jewelry. Our 63 participants were more likely to recommend specific features rather than specific products, and they were more likely to focus on mobility rather than cognitive or sensory issues. However, when directly asked to make suggestions for a person who had sensory or cognitive concerns, the salespeople were generally able to do so. We found no evidence that the type of store, the salesperson's gender, or the salesperson's age predicted the amount of usability information they could provide. However, we did learn that the people who provided the most suggestions generally reported coming up with their advice through direct interaction with older adults rather than from reading product literature or from personal product use.
Analysis of Bread Bag Closures for Individuals with Rheumatoid Arthritis BIBAFull-Text 1917-1921
  Ruth A. K. Loewenhardt
The purpose of this study was to analyze four different plastic bag closure devices to determine if there was a difference in their ease of use for individuals with Rheumatoid Arthritis (RA) between closures currently on the market and an autoclave bag closure currently in use in medical laboratories. This was based on research into issues experienced by individuals with RA and their abilities to perform activities of daily living. This study evaluated the issues of opening and closing bread bags so that they are accessible to people with functional limitations due to the effects of RA. It was determined that the autoclave closure is not a preferred instrument for use by individuals with RA due to the difficulties in small object manipulation, the strength required to use the device and its unfamiliarity. However, closures currently available pose considerable frustration to the user and need to be re-evaluated.
Indian Users Expectations for the Location of Web Objects on Informational Websites BIBAFull-Text 1922-1926
  A. Dawn Shaikh; Barbara S. Chaparro; Anirudha Joshi
Previous research has established that users form mental models of web page layout. Bernard (2001, 2002) demonstrated that users expect web objects to be located in specific places on a web page. Further research has attempted to evaluate users' expectations on a global level (Bernard & Sheshadri, 2004). Th3 study discussed in this paper used a similar methodology on students at an Indian university in Mumbai in order to determine the structure of the Indian user's mental model for web page layout. India is one of the fastest growing Internet user markets in the world. With a predicted 100 million users by 2007, it is essential to get a better understanding of the Indian user. This paper graphically identifies the expected location of five web objects (back to home link, about us link, site search engine, internal links, and advertisements) commonly found on informational websites. Suggestions for overall page layout are also provided.
Individual Differences in Working Memory Capacity and Site Complexity Predict Recall from Web Pages BIBAFull-Text 1927-1931
  Holly Blasko-Drabik; Katie Hinds; Valerie K. Sims
Participants with either high or low working memory operation spans interacted with one of three websites and then recalled both the layout and content they experienced. Websites varied in terms of complexity, with more complex sites containing more dense text and additional animations. Results showed that site complexity predicted general content recall, whereas working memory span predicted both specific layout recall and specific content recall. Working memory operation span is an important predictor of interactions with websites, and this variable predicts beyond information about site complexity.
Anthropomorphism of Textured Faces BIBAFull-Text 1932-1935
  Daniel Barber; Valerie K. Sims; Matthew G. Chin; Matthew Velie; David J. Sushil; Aaron A. Pepe; Linda U. Ellis; Randall Shumaker; Neal Finkelstein
Participants rated machine "faces" which varied in terms of facial feature shape, face shape, and eight facial background textures. Ratings were made for aggression, friendliness, intelligence, trustworthiness, and degree of animation. In addition, reaction time was collected for all ratings. Rough metal and blank facial backgrounds were perceived most trustworthy. Rough metal also had the highest mean friendliness. However, across ratings, face shape and feature shape proved to have more predictive validity than did the materials making up the face. It is likely that when faced with ambiguous objects, such as the front of a novel military vehicle, people project anthropomorphic features and then make judgments accordingly.
Misuse of Human and Automated Decision Aids in a Soldier Detection Task BIBAFull-Text 1936-1940
  Mary T. Dzindolet; Linda G. Pierce; Hall P. Beck
Providing human operators with automated decision aids does not always improve performance. In this study, 24 students viewed terrain slides, half of which included a camouflaged soldier. After viewing each slide, participants could view the decision reached by a human or automated aid, or continue without the help of an aid. Some of the participants were led to believe their aids were experts; others were not. Significantly more participants showed a preference to view human rather than automated aid decisions. However, participants were as likely to misuse an automated aid as they were a human aid. These biases existed regardless of the perceived expertise of the aids. In addition, results of a linguistic analysis of open-ended descriptions of automated and human aids suggest human operators view automated and human aids differently and have implications for training and system development.
Management of Multiple Uavs with Imperfect Automation BIBAFull-Text 1941-1944
  Brian R. Levinthal; Christopher D. Wickens
Forty-two participants manipulated two or four unmanned aerial vehicles (UAVs) while monitoring an adjacent display for camouflaged tanks. They were sometimes supported in the tank-detection task by an automated target recognition system that operated at either a reliability of .9 with a threshold designed to provide an equal number of false-alarms and misses, .6 with a low threshold producing more automation false alarms, or .6 with a high threshold producing more automation misses. As taskload doubled, performance on the UAV task was significantly reduced. The effect was not mediated by the presence of automated aids, though the aids did influence performance in the tank-detection task. Tank detection was improved by both the highly-reliable aid and (to a lesser extent) by the miss-prone aid, but was not improved (and sometimes hurt) by the false-alarm prone condition. The results support the independence model of reliance and compliance proposed by Meyer (2001).
How Does Manipulation of Secondary Task Scheduling Affect Human Performance BIBAFull-Text 1945-1948
  Patrice D. Tremoulet; Kathleen M. Stibler; Patrick Craven; Joyce Barto