| Special issue on Spatial and Image-based Information Systems | | BIB | Full-Text | 1-2 | |
| Richard Chbeir; Kokou Yetongnon; Christophe Claramunt | |||
| A global process to access documents' contents from a geographical point of view | | BIBAK | Full-Text | 3-23 | |
| Mauro Gaio; Christian Sallaberry; Patrick Etcheverry; Christophe Marquesuzaa; Julien Lesbegueries | |||
| Local cultural heritage document repositories are characterized by contents
strongly attached to a territory (i.e. geographical references). The user must
be able to consider such repositories according to a focus, which takes into
account his/her geographical interests, and which allows one to access the
relevant document's contents from a geographical point of view.
This paper presents the Virtual Itineraries in the Pyrenees (PIV) project. Spatial and temporal core models are proposed to give a formal representation of geographical information. The models take into account the characteristics of heterogeneous human modes of expression: written language and captures of drawings, maps, pictures, etc. Semantic processes have been built to automatically manage the spatial and temporal information from non-structured data. A "back office" prototype, which adds these processes to classic information extraction (IE) approaches, while associating a geographical information retrieval (GIR) service is proposed. This service searches for any links between formal representations of geographic information in document collections, and similar representations in a user's information query. Finally, the paper presents the design work, giving the details of the principles of result visualization and navigation, while proposing a "front office" first implementation of the system. Keywords: Core geographic feature model; Non-structured data; Semantic processing; Content-based information access; Cartographic information visualization; Heterogeneous expression modes | |||
| Indexing for multipoint interactive similarity retrieval in iconic spatial image databases | | BIBAK | Full-Text | 24-38 | |
| Xiao Ming Zhou; Chuan Heng Ang; Tok Wang Ling | |||
| Similarity-based retrieval of images is an important task in many image
database applications. Interactive similarity retrieval is one way to resolve
the fuzzy area involving psychological and physiological factors of individuals
during the retrieval process. A good interactive similarity system depends not
only on a good similarity measure, but also on the structure of the image
database and the related retrieval process. In this paper, we propose to use a
dynamic similarity measure on top of the enhanced digraph index structure for
interactive iconic image similarity retrieval. Our approach makes use of the
multiple feedbacks from the user to get the hidden subjective information of
the retrieval, and avoids the high cost of re-computation of an interactive
retrieval algorithm. Keywords: Iconic image; Interactive; Similarity retrieval | |||
| User Hints for map labeling | | BIBAK | Full-Text | 39-74 | |
| Hugo A. D. do Nascimento; Peter Eades | |||
| Cartography is one of the oldest forms of visualization. It has applications
not only in geography but in many other science fields. A significant visual
problem in cartography is the map-labeling problem, which consists of assigning
positions for the labels of graphical features of a map so that these elements
can be uniquely identified. Although much research has been done on map
labeling, practical labeling processes still demand intensive manual work to
produce high-quality solutions. One reasons for this is that the optimization
problems associated with map labeling are NP-hard. More importantly, existing
automatic labeling methods do not incorporate all kinds of domain knowledge
that may be of interest for a cartographer. In the present paper, we describe
an interactive framework for assisting cartographers in the map-labeling
problem. We treat labeling processes as an optimization task, and support human
interaction combined with fully automatic methods in a general framework that
we call User Hints. An interactive map-labeling system based on the User Hints
framework is presented, and an evaluation of such system with real experts in
cartography is described. This evaluation shows that our interactive
map-labeling framework is promising. Keywords: Map labeling; Optimization; User interface; Visualization | |||
| Qualitative spatial reasoning about relative point position | | BIBAK | Full-Text | 75-98 | |
| Reinhard Moratz; Marco Ragni | |||
| Qualitative spatial reasoning (QSR) abstracts metrical details of the
physical world. The two main directions in QSR are topological reasoning about
regions and reasoning about orientations of point configurations. Orientations
can refer to a global reference system, e.g. cardinal directions or instead
only to relative orientation, e.g. egocentric views. Reasoning about relative
orientations poses additional difficulties compared to reasoning about
orientations in an absolute reference frame.
Qualitative knowledge about relative orientation can be naturally expressed in the form of ternary point calculi. Designing such calculi requires compromising between desired mathematical properties and the power to describe and model concrete "real-world" problems. Research has shown that using basic notions such as granularity leads to imprecise reasoning and as a consequence to underdetermined knowledge which is difficult to handle efficiently. Concrete problems need a combination of qualitative knowledge of orientation and qualitative knowledge of distance. We present a calculus based on ternary relations where we introduce a qualitative distance measurement based on two of the three points. Its main advantage is that it utilizes finer distinctions than previously published calculi. Furthermore, it permits differentiations which are useful in realistic application scenarios such as robot navigation that cannot be directly dealt with in coarser calculi. Keywords: Qualitative spatial reasoning; Cognitive modelling; Robot navigation | |||
| Interactive visual analysis of geographic data on mobile devices based on dynamic queries | | BIBAK | Full-Text | 99-122 | |
| Stefano Burigat; Luca Chittaro | |||
| The capabilities of current mobile devices, especially PDAs, are making it
possible to design and develop mobile applications that employ visual
techniques for using geographic data in the field. These applications can be
extremely useful in areas as diverse as tourism, business, natural resources
management and homeland security. In this paper, we present a system aimed at
supporting users in the exploratory analysis of geographic data on PDAs through
a highly interactive interface based on visual dynamic queries. We propose
alternative visualizations to display query results and present an experimental
evaluation aimed at comparing their effectiveness on a PDA in a tourist
scenario. Our findings provide an experimental confirmation of the
unsuitability of the typical visualization, employed by classic dynamic query
systems, which displays only those results that fully satisfy a query, in those
cases where only sub-optimal results are obtainable. For such cases, the
results of our study highlight the usefulness of visualizations that display
all results and their degree of satisfaction of the query. Keywords: Visualization; Geographic information systems; Mobile devices; Dynamic queries | |||
| Filmification of methods: A visual language for graph algorithms | | BIBAK | Full-Text | 123-150 | |
| Yutaka Watanobe; Nikolay N. Mirenkov; Rentaro Yoshioka; Oleg Monakhov | |||
| A novel approach for using the filmification of methods concept in the graph
algorithm representation, specification, and programming is considered. It is
based on a "cyberFilm" format, where a set of multimedia frames represents
algorithmic features. A brief description of the cyberFilm concept and an
observation of graph algorithm features are presented. A number of cyberFilms
related to Prim's and Dijkstra's algorithms have been developed and used to
explain the basic ideas of the approach. Several versions of the algorithm
visualization are demonstrated by corresponding examples of cyberFilm frames
and icon language representations. In addition, a method for program generation
from the cyberFilm specification is provided with explanations of program
templates supporting the cyberFilm frames. Keywords: Visual programming languages; CyberFilm; Graph algorithms; Program templates | |||
| A formalism for visual security protocol modeling | | BIBAK | Full-Text | 153-181 | |
| J. McDermott; G. Allwein | |||
| Existing visual modeling paradigms do not adequately cover the visual
modeling of security protocols: sequences of interactions between principals in
a security system. A visual formalism for security protocol modeling should not
only be well-defined but also satisfy certain pragmatic criteria: support for
compositional, comprehensive, laconic, and lucid models. Candidate techniques
from the OMG's Model Driven Architecture, based largely on UML 2.0, lack a
formal syntax and semantics. Well-defined visual formalisms outside of UML have
shortcomings with respect to one or more of the pragmatic criteria. We present
the GSPML visual formalism as a solution that satisfies all of the pragmatic
criteria. We show that GSPML is well-defined with structural operational
semantics and a hypergraph grammar syntax. Keywords: Model driven architecture; Live sequence chart; Statechart; Petri net; Process algebra; Security protocol; Hypergraph grammar | |||
| MAVIS: A multi-level algorithm visualization system within a collaborative distance learning environment | | BIBAK | Full-Text | 182-202 | |
| Igal Koifman; Ilan Shimshoni; Ayellet Tal | |||
| This paper presents a new model for an algorithm visualization system. Our
model views the visualization system as an integral part of a broader distance
learning environment. As such, it supports the heterogeneity of the Internet
the visualization is expected to run on and the diversity of the expected
users. It does so by defining several ways for handling multi-level
visualizations. First, a visualization can run in various abstraction levels of
the algorithm, depending on the familiarity of the students with the studied
materials. Second, a visualization can use various levels of graphics,
depending on the capabilities of the client machines. Third, the messages sent
between the machines can be of various levels, depending on the communication
loads. Another important aspect of a distance learning environment is
collaboration and data sharing. Our model facilitates the collaboration between
the students and the instructor and between the students themselves. Finally,
this paper presents a system, MAVIS, that realizes the model, and demonstrates
its use on several algorithms. Keywords: Algorithm visualization; Algorithm animation; Distance learning; Collaboration | |||
| Interactive access to large image collections using similarity-based visualization | | BIBAK | Full-Text | 203-224 | |
| G. P. Nguyen; M. Worring | |||
| Image collections are getting larger and larger. To access those
collections, systems for managing, searching, and browsing are necessary.
Visualization plays an essential role in such systems. Existing visualization
systems do not analyze all the problems occurring when dealing with large
visual collections. In this paper, we make these problems explicit. From there,
we establish three general requirements: overview, visibility, and structure
preservation. Solutions for each requirement are proposed, as well as functions
balancing the different requirements. We present an optimal visualization
scheme, supporting users in interacting with large image collections.
Experimental results with a collection of 10,000 Corel images, using simulated
user actions, show that the proposed scheme significantly improves performance
for a given task compared to the 2D grid-based visualizations commonly used in
content-based image retrieval. Keywords: Content-based image retrieval; Similarity-based visualization; Interaction | |||
| An agent-based framework for sketched symbol interpretation | | BIBAK | Full-Text | 225-257 | |
| Giovanni Casella; Vincenzo Deufemia; Viviana Mascardi; Gennaro Costagliola; Maurizio Martelli | |||
| Recognizing hand-sketched symbols is a definitely complex problem. The input
drawings are often intrinsically ambiguous, and require context to be
interpreted in a correct way. Many existing sketch recognition systems avoid
this problem by recognizing single segments or simple geometric shapes in a
stroke. However, for a recognition system to be effective and precise, context
must be exploited, and both the simplifications on the sketch features, and the
constraints under which recognition may take place, must be reduced to the
minimum.
In this paper, we present an agent-based framework for sketched symbol interpretation that heavily exploits contextual information for ambiguity resolution. Agents manage the activity of low-level hand-drawn symbol recognizers, that may be heterogeneous for better adapting to the characteristics of each symbol to be recognized, and coordinate themselves in order to exchange contextual information, thus leading to an efficient and precise interpretation of sketches. We also present AgentSketch, a multi-domain sketch recognition system implemented according to the proposed framework. A first experimental evaluation has been performed on the domain of UML Use Case Diagrams to verify the effectiveness of the proposed approach. Keywords: Sketch understanding; Agent-based systems; Diagram recognition; Visual language parsing | |||
| Visualization of cryptographic protocols with GRACE | | BIBAK | Full-Text | 258-290 | |
| G. Cattaneo; A. De Santis; U. Ferraro Petrillo | |||
| In this paper we present GRACE (graphical representation and animation for
cryptography education), a Java-based educational tool that can be used to help
in teaching and understanding of cryptographic protocols.
The tool adopts an active learning model that engages the learner by asking him to describe, in an exemplification of a real-world scenario, cryptographic protocols using simple primitives whose effects are visualized by means of animated sequences. To this end, the GRACE interface offers the learner the choice of several cryptographic and non-cryptographic related operations with their respective visualizations. By executing a series of these operations in the proper order, a teacher is able to provide a visual introductory description of several protocols. Moreover, since some of the cryptographic operations are not just simulated but concretely implemented, it can be used by students to see which elaborations are performed by each operation of a cryptographic protocol, and their effects on the represented scenario. GRACE comes equipped with the implementation of several cryptographic primitives and cryptosystems. Additional primitives and cryptosystems can easily be plugged in the system. Visualizations prepared with GRACE can be edited, navigated and saved in a file for playback. We also present the results of an experimental lesson taught in the Security on Communication Networks undergraduate course at the University of Salerno during the fall 2004 semester using GRACE. A copy of GRACE and some demo lessons featuring the visualization of some cryptographic protocols are available at http://www.dia.unisa.it/research/grace. Keywords: Educational tool; Cryptographic protocols; Protocol visualization | |||
| Visual software tools for bioinformatics | | BIBAK | Full-Text | 291-301 | |
| Timothy Arndt | |||
| Bioinformatics is the application of techniques from computer science,
statistics and mathematics to problems in molecular biology. This
interdisciplinary approach is rapidly revolutionizing biology. A survey of
software tools for bioinformatics is presented. A special emphasis is placed on
the visual aspects of these tools. The most important visualization tasks in
bioinformatics are data sequence visualization and visualizing protein
structures. The visualization of interactions between molecules in a metabolic
pathway or network is an emerging area. Many important visualization techniques
have yet to be applied in this application area. Keywords: Bioinformatics; Software tools; Reviews | |||
| MOVIS: A system for visualizing distributed mobile object environments | | BIBAK | Full-Text | 303-320 | |
| Yaniv Frishman; Ayellet Tal | |||
| This paper presents MOVIS -- a system for visualizing mobile object
frameworks. In such frameworks, the objects can migrate to remote hosts, along
with their state and behavior, while the application is running. An innovative
graph-based visualization is used to depict the physical and the logical
connections in the distributed object network. Scalability is achieved by using
a focus + context technique jointly with a user-steered clustering algorithm.
In addition, an event synchronization model for mobile objects is presented.
The system has been applied to visualizing several mobile object applications. Keywords: Distributed software visualization; Mobile objects; Dynamic graph layout | |||
| Representing short-term observations of moving objects by a simple visual language | | BIBAK | Full-Text | 321-342 | |
| Björn Gottfried | |||
| In a variety of dynamical systems, formations of motion patterns occur.
Observing colonies of animals, for instance, for the scientist it is not only
of interest which kinds of formations these animals show, but also how they
altogether move around. In order to analyse motion patterns for the purpose of
making predictions, to describe the behaviour of systems, or to index databases
of moving objects, methods are required for dealing with them. This becomes
increasingly important since a number of technologies have been devised which
allow objects precisely to get traced. However, the indeterminacy of spatial
information in real world environments also requires techniques to approximate
reasoning, for example, in order to compensate for small and unimportant
distinctions which are due to noisy measurements. As a consequence, precise as
well as coarse motion patterns have to be dealt with.
A set of 16 atomic motion patterns is proposed. On the one hand, a relation algebra is defined on them. On the other hand, these 16 relations form the basis of a visual language using which motion patterns can easily be dealt with in a diagrammatic way. The relations are coarse but crisp and they allow imprecise knowledge about motion patterns to be dealt with, while their diagrammatic realisation also allow precise patterns to get handled. While almost all approaches consider motion patterns along arbitrary time intervals, this paper in particular focuses on short-term motion patterns as we permanently observe them in our everyday life. The bottom line of the current work, however, is yet more general. While it has been widely argued that it makes sense to use both sentential and diagrammatic representations in order to represent different things in the same system adequately (and hence differently), we argue that it makes even sense to represent the same things differently in order to grasp different aspects of one and the same object of interest from different viewpoints. We demonstrate this by providing both a sentential and a diagrammatic representation for the purpose of grasping different aspects of motion patterns. It shows that both representations complement each other. Keywords: Qualitative spatial reasoning; Motion pattern; Change of formation; Relation algebra; Diagrammatic representation | |||
| Defining the abstract syntax of visual languages with advanced graph grammars -- A case study based on behavior trees | | BIBAK | Full-Text | 343-379 | |
| Lars Grunske; Kirsten Winter; Nisansala Yatapanage | |||
| Diagrammatic visual languages can increase the ability of engineers to model
and understand complex systems. However, to effectively use visual models, the
syntax and semantics of these languages should be defined precisely. Since most
diagrammatic visual models that are currently used to specify systems can be
described as (directed) typed graphs, graph grammars have been identified as a
suitable formalism to describe the abstract syntax of visual modeling
languages. In this article, we investigate how advanced graph-transformation
techniques, such as conditional, structure-generic and type-generic
graph-transformation rules, can help to improve and simplify the specification
of the abstract syntax of a visual modeling language. To demonstrate the
practicability of an approach that unifies these advanced graph-transformation
techniques, we define the abstract syntax of behavior trees (BTs), a graphical
specification language for functional requirements. Additionally, we provide a
translational semantics of BTs by formalizing a translation scheme to the input
language of the SAL model checking tool for each of the graph-transformation
rules. Keywords: Visual modeling languages; Advanced graph-transformation techniques; Graph grammars; Abstract syntax definition; Semantics of visual languages; Model checking | |||
| Visual Zero: A persistent and interactive object-oriented programming environment | | BIBAK | Full-Text | 380-398 | |
| J. Baltasar García Perez-Schofield; Emilio García Roselló; Francisco Ortín Soler; Manuel Pérez Cota | |||
| In this article, an ongoing research project held in the Computer Science
department of the University of Vigo is described. Its main objective is to
develop an interactive object-oriented environment, serving as a vehicle for
learning object-oriented programming. It currently consists of a virtual
machine, an assembler, compilers for two high-level programming languages, and
an educational visual programming environment. Its main characteristics are (a)
the support of prototype-based object orientation, which is a model of object
orientation that actually wraps the class-based model; (b) the support for
object persistence, which simplifies all input/output issues to the minimum,
and (c) the availability of a new visual programming environment is an
invaluable help. We the authors think that the combination of all of these
possibilities, will lead to an interesting, useful tool that would be
recommended for object-oriented teaching. The whole system has been
successfully employed in a number of different courses, allowing students to
concentrate on objects and their relationships from the very beginning, and
thus helping them to achieve a high degree of knowledge about the
object-oriented programming paradigm. Keywords: Visual programming; Object-oriented paradigm | |||
| Visual specification of measurements and redesigns for domain specific visual languages | | BIBAK | Full-Text | 399-425 | |
| Esther Guerra; Juan de Lara; Paloma Díaz | |||
| Ensuring model quality is a key success factor in many computer science
areas, and becomes crucial in recent software engineering paradigms like the
one proposed by model-driven software development. Tool support for
measurements and redesigns becomes essential to help developers improve the
quality of their models. However, developing such helper tools for the wide
variety of (frequently domain specific) visual notations used by software
engineers is a hard and repetitive task that does not take advantage from
previous developments, thus being frequently forgotten.
In this paper we present our approach for the visual specification of measurements and redesigns for Domain Specific Visual Languages (DSVLs). With this purpose, we introduce a novel DSVL called SLAMMER that contains generalisations of some of the more used types of internal product measurements and redesigns. The goal is to facilitate the task of defining measurements and redesigns for any DSVL, as well as the generation of tools from such specification reducing or eliminating the necessity of coding. We rely on the use of visual patterns for the specification of the relevant elements for each measurement and redesign type. In addition, SLAMMER allows the specification of redesigns either procedurally or by means of graph transformation rules. These redesigns can be triggered when the measurements reach a certain threshold. These concepts have been implemented in the meta-modelling tool AToM3. In this way, when a DSVL is designed, it is possible to specify measurements and redesigns that will become available in the final modelling environment generated for the language. As an example, we show a case study in the web modelling domain. Keywords: Domain specific visual language; Meta-modelling; Measurement; Redesign; Graph transformation; Graphical pattern | |||
| Special issue on selected papers from VL/HCC 2007: Guest Editors' introduction | | BIB | Full-Text | 427-428 | |
| Philip Cox; John Hosking | |||
| Enforced generative patterns for the specification of the syntax and semantics of visual languages | | BIBAK | Full-Text | 429-455 | |
| Paolo Bottoni; Esther Guerra; Juan de Lara | |||
| We present the new notion of enforced generative pattern, a structure that
declares positive or negative conditions that must be satisfied by a model.
Patterns are applied to transformation rules resulting in new rules that modify
models according to the pattern specification. In the case of a negative
pattern, an application condition is added to the rule. In the case of a
positive one, the rule is modified to consider additional context in its
left-hand side and to increase its effects. We have defined these patterns in
an abstract setting, which enables their instantiation for different
structures, like graphs, triple graphs and graph transformation rules.
We apply the previous concepts to the specification of the syntax and semantics of visual languages. In particular, we show instantiations for: (i) graphs, with applications at the syntactical level; (ii) triple graphs, for the coordination of syntax and static semantics; and (iii) rules, for the incremental construction of execution rules. We present some examples that illustrate the usefulness of the combination of these three instantiations. In particular, we show the specification of environments for visual languages with token-holder semantics, discrete-event semantics and communication semantics. Keywords: Visual languages; Graph transformation; Triple graph grammars; Graph constraints; Patterns; Meta-modelling; Specification of semantics | |||
| Statechart features and pre-release maintenance defects | | BIBAK | Full-Text | 456-467 | |
| Jeanette Heidenberg; Andreas Nåls; Ivan Porres | |||
| Statecharts is a design notation for reactive systems that is part of the
Unified Modeling Language (UML) and is commonly used in the automotive and
telecommunication software industry. In this paper we present a study on how
the use of some statechart features correlate to the number of pre-release
maintenance defects in large systems developed using mainly this notation. We
discuss possible causes for these correlations and conduct a comparative study
to verify these. We conclude by providing advice to UML practitioners. Keywords: Statecharts; Software maintenance; Software design | |||
| Design planning by end-user web developers | | BIBAK | Full-Text | 468-484 | |
| Mary Beth Rosson; Hansa Sinha; Mithu Bhattacharya; Dejin Zhao | |||
| We report an exploratory research project that investigates the impacts of
different forms of design planning on end users asked to develop a simple
interactive web application. End users created their projects (a Ride Board
application) using the CLICK end-user web development tool [J. Rode,
User-centered design of end-user web development tool, Ph.D. Dissertation,
Department of Computer Science, Virginia Tech, Blacksburg, VA, USA, 2005]. Some
participants were asked to create a conceptual map to plan their projects and
others to write user interaction scenarios; a third group was asked to do
whatever they found useful. We describe the planning that each group underwent,
how they approached the web development task, and their reactions to the
experience afterwards. The overall pattern of results suggests that while the
participants who planned using scenarios felt they better understood the web
development task, it was the group who created concept maps that explored and
incorporated more of the novel programming features of the CLICK tool. We also
discuss the role of gender in the CLICK development task, noting that women
were less likely to explore the tool's novel features and perceived themselves
as less successful in the task. We conclude with a discussion of design
implications and future work. Keywords: End-user programming; Web development; Design; Concept maps | |||
| Using scenario-based requirements to direct research on web macro tools | | BIBAK | Full-Text | 485-498 | |
| Christopher Scaffidi; Allen Cypher; Sebastian Elbaum; Andhy Koesnandar; Brad Myers | |||
| Web macros automate the interactions of end users with web sites and related
information systems. Though web macro recorders and players have grown in
sophistication over the past decade, these tools cannot yet meet many tasks
that people perform in daily life. Based on observations of browser users, we
have compiled ten scenarios describing tasks that users would benefit from
automating. Our analysis of these scenarios yields specific requirements that
web macro tools should support if those tools are to be applicable to these
real-life tasks. Our set of requirements constitutes a benchmark for evaluating
tools, which we demonstrate by evaluating the Robofox, CoScripter, and iMacros
tools. Keywords: End-user programming; Web macros; Scripting | |||
| Evaluating and generalizing constraint diagrams | | BIBAK | Full-Text | 499-521 | |
| Gem Stapleton; Aidan Delaney | |||
| The constraint diagram language was designed to be used in conjunction with
the unified modelling language (UML), primarily for placing formal constraints
on software models. In particular, constraint diagrams play a similar role to
the textual object constraint language (OCL) in that they can be used for
specifying system invariants and operation contracts in the context of a UML
model. Unlike the OCL, however, constraint diagrams can be used independently
of the UML. In this paper, we illustrate a range of intuitive and
counter-intuitive features of constraint diagrams and highlight some
(potential) expressiveness limitations. The counter-intuitive features are
related to how the individual pieces of syntax interact. A generalized version
of the constraint diagram language that overcomes the illustrated
counter-intuitive features and limitations is proposed. In order to discourage
specification readers and writers from overlooking certain semantic
information, the generalized notation allows this information to be expressed
more explicitly than in the non-generalized case. The design of the generalized
notation takes into account five language design principles which are discussed
in the paper. We provide a formalization of the syntax and semantics for
generalized constraint diagrams. Moreover, we establish a lower bound on the
expressiveness of the generalized notation and show that they are at least as
expressive as constraint diagrams. Keywords: Constraint diagrams; Precise software specification; Diagrammatic specification; Expressiveness | |||
| Proposing a speech to gesture translation architecture for Spanish deaf people | | BIBAK | Full-Text | 523-538 | |
| R. San-Segundo; J. M. Montero; J. Macías-Guarasa; R. Córdoba; J. Ferreiros; J. M. Pardo | |||
| This article describes an architecture for translating speech into Spanish
Sign Language (SSL). The architecture proposed is made up of four modules:
speech recognizer, semantic analysis, gesture sequence generation and gesture
playing. For the speech recognizer and the semantic analysis modules, we use
software developed by IBM and CSLR (Center for Spoken Language Research at
University of Colorado), respectively. Gesture sequence generation and gesture
animation are the modules on which we have focused our main effort. Gesture
sequence generation uses semantic concepts (obtained from the semantic
analysis) associating them with several SSL gestures. This association is
carried out based on a number of generation rules. For gesture animation, we
have developed an animated agent (virtual representation of a human person) and
a strategy for reducing the effort in gesture animation. This strategy consists
of making the system automatically generate all agent positions necessary for
the gesture animation. In this process, the system uses a few main agent
positions (two or three per second) and some interpolation strategies, both
issues previously generated by the service developer (the person who adapts the
architecture proposed in this paper to a specific domain). Related to this
module, we propose a distance between agent positions and a measure of gesture
complexity. This measure can be used to analyze the gesture perception versus
its complexity. With the architecture proposed, we are not trying to build a
domain independent translator but a system able to translate speech utterances
into gesture sequences in a restricted domain: railway, flights or weather
information. Keywords: Animation; Animated agents; Lifelike characters; Spanish sign language; Speech to gesture translation; Gesture complexity | |||
| A diagrammatic reasoning system for the description logic | | BIBAK | Full-Text | 539-573 | |
| Frithjof Dau; Peter Eklund | |||
| Diagrammatic reasoning is a tradition of visual logic that allows sentences
that are equivalent to first order logic to be written in a visual or
structural form: usually for improved usability. A calculus for the diagram can
then be defined that allows well-formed formulas to be derived. This calculus
is intended in the analog of logical inference.
Description logics (DLs) have become a popular knowledge representation and processing language. DLs correspond to decidable fragments of first order logic; their notation is in the style of symbolic, variable-free formulas. Moreover, DLs are equipped with table au theorem provers that are proven to be sound and complete. Although DLs have roots in diagrammatic languages (such as semantic networks), they are elaborated in a purely symbolic manner. This paper discusses how DLs can be equivalently represented in terms of a diagrammatic reasoning system. First, existing diagrammatic reasoning systems, namely spider- and constraint diagrams, as well as existential and conceptual graphs, are investigated to determine if they are compatible with DLs. It turns out that Peirce's existential graphs are better suited for this purpose than the alternatives we examine. The paper then redevelops the DL ALC, which is the smallest propositional DL, by means of labeled trees, and provides a diagrammatic representation for these trees in the style of Peircean graphs. We provide a calculus based on C.S. Peirce's calculus for existential graphs and prove the soundness and completeness of the calculus. The calculus acts on labeled trees, but can be best understood as a diagrammatic calculus whose rules modify the Peircean-style representation of ALC. Keywords: Description logics; Spider diagrams; Constraint diagrams; Conceptual graphs; Existential graphs; Logic; Syntax; Semantics; Calculus | |||
| Towards a specification of the ToonTalk language | | BIBAK | Full-Text | 574-597 | |
| Leonel Morgado; Ken Kahn | |||
| ToonTalk is a child-oriented programming language whose environment is an
animated virtual world, with objects that children can pick up and use as in a
game, such as birds, trucks, and robots, providing direct child-oriented
metaphors for programming constructs. Actions performed by a programmer's
avatar with these objects are both code and coding. ToonTalk is a powerful
system, not just a "toy" system: it is based upon concurrent constraint
programming languages, and programs written in languages such as Flat Guarded
Horn Clauses and Flat Concurrent Prolog can be straight-forwardly constructed
in ToonTalk. However, there is not a specification of ToonTalk, for ready
implementation in other environments. We propose that the ToonTalk language
lies not in the animations displayed by the current environment, but on the
actions performed by the programmer with virtual world objects; we present a
description and analysis of the methods the ToonTalk language provides to
programmers for expressing programs. Keywords: ToonTalk; Animated programming; Action-based programming; Children programming; Concurrent programming; Virtual environments; Virtual worlds; Virtual environment | |||
| Balanced cognitive load significantly improves the effectiveness of algorithm animation as a problem-solving tool | | BIBAK | Full-Text | 598-616 | |
| M. Eduard Tudoreanu; Eileen Kraemer | |||
| The question of whether animations depicting running algorithms are
beneficial in helping users has received mixed results. This paper provides
evidence that the effectiveness of animations as an aid in performing a task is
affected by several factors that have no influence on text-only aids. We make
our case by comparing two separate studies designed to measure whether the
addition of animations to textual descriptions of a running computation
promotes understanding of distributed algorithms. The text-based conditions in
both experiments resulted in statistically similar results, while the
animation-added conditions resulted in different outcomes. The best
visualization condition outperforms all other conditions by a significant
margin. The factors that were different between the two experiments fall under
the concept of cognitive economy. Therefore, the degree of cognitive economy is
important both for empirical studies that involve animation and for practical
applications in which people rely on dynamic visualization to solve an
algorithmic problem. Keywords: Algorithm animation; Cognitive economy; External cognition; Animation of distributed algorithms | |||
| A survey of methods for image annotation | | BIBAK | Full-Text | 617-627 | |
| Allan Hanbury | |||
| In order to evaluate automated image annotation and object recognition
algorithms, ground truth in the form of a set of images correctly annotated
with text describing each image is required. In this paper, three image
annotation approaches are reviewed: free text annotation, keyword annotation
and annotation based on ontologies. The practical aspects of image annotation
are then considered. We discuss the creation of keyword vocabularies for use in
automated image annotation evaluation. As direct manual annotation of images
requires much time and effort, we also review various methods to make the
creation of ground truth more efficient. An overview of annotated image
datasets for computer vision research is provided. Keywords: Image annotation; Object recognition; Computer vision; Ontology; Algorithm evaluation | |||
| An exploration of diversified user strategies for image retrieval with relevance feedback | | BIBAK | Full-Text | 629-636 | |
| Michel Crucianu; Jean-Philippe Tarel; Marin Ferecatu | |||
| Given the difficulty of setting up large-scale experiments with real users,
the comparison of content-based image retrieval methods using relevance
feedback usually relies on the emulation of the user, following a single,
well-prescribed strategy. Since the behavior of real users cannot be expected
to comply to strict specifications, it is very important to evaluate the
sensitiveness of the retrieval results to likely variations of users' behavior.
It is also important to find out whether some strategies help the system to
perform consistently better, so as to promote their use. Two selection
algorithms for relevance feedback based on support vector machines are compared
here. In these experiments, the user is emulated according to eight
significantly different strategies on four ground truth databases of different
complexity. It is first found that the ranking of the two algorithms does not
depend much on the selected strategy. Also, the ranking of the strategies
appears to be relatively independent of the complexity of the ground truth
databases, which allows to identify desirable characteristics in the behavior
of the user. Keywords: Content-based retrieval; User strategy; User emulation; Evaluation | |||
| Spatial inference and similarity retrieval of an intelligent image database system based on object's spanning representation | | BIBAK | Full-Text | 637-651 | |
| Po-Whei Huang; Lipin Hsu; Yan-Wei Su; Phen-Lan Lin | |||
| In this paper, we presented a novel image representation method to capture
the information about spatial relationships between objects in a picture. Our
method is more powerful than all other previous methods in terms of accuracy,
flexibility, and capability of discriminating pictures. In addition, our method
also provides different degrees of granularity for reasoning about directional
relations in both 8- and 16-direction reference frames. In similarity
retrieval, our system provides twelve types of similarity measures to support
flexible matching between the query picture and the database pictures. By
exercising a database containing 3600 pictures, we successfully demonstrated
the effectiveness of our image retrieval system. Experiment result showed that
97.8% precision rate can be achieved while maintaining 62.5% recall rate; and
97.9% recall rate can be achieved while maintaining 51.7% precision rate. On an
average, 86.1% precision rate and 81.2% recall rate can be achieved
simultaneously if the threshold is set to 0.5 or 0.6. This performance is
considered to be very good as an information retrieval system. Keywords: Image database; Image representation; Spatial inference; Similarity retrieval | |||
| Concept keyboards in the animation of standard algorithms | | BIBAK | Full-Text | 652-674 | |
| Nelson Baloian; Henning Breuer; Wolfram Luther | |||
| Software visualization and algorithm animation have been tackled almost
exclusively from the visual point of view; this means representation and
control occur through the visual channel. This approach has its limitations. To
achieve better comprehension, we deal with multimodal interfaces that include
the extended facilities of interaction together with those of the standard
systems for data visualization and algorithm animation. The notion of specific
concept keyboards is introduced. As a consequence, modern information and
learning systems for algorithm animation are enhanced in such a way that
control and interaction take place through appropriate interfaces designed and
semi-automatically generated for this special purpose. In this paper, we
provide some examples and report on a thorough evaluation to show the relevance
of this new approach. Keywords: Concept keyboards; Algorithm animation; Algorithm visualization; XML-based interface description | |||
| Euler diagram generation | | BIBAK | Full-Text | 675-694 | |
| J. Flower; A. Fish; J. Howse | |||
| Euler diagrams form the basis of many diagrammatic notations used to
represent set theoretic relationships in a wide range of contexts including:
file system information, statistical data representation, object-oriented
modeling, logical specification and reasoning systems, and database search
queries.
An abstract Euler diagram is a formal abstract description of the information that is to be displayed as a concrete (or drawn) Euler diagram. If the abstract diagram can be visualized, whilst satisfying certain desirable visual properties (called well-formedness conditions), then we say the diagram is drawable. We solve the drawability problem for a given set of well-formedness conditions, identifying the properties which classify a diagram as drawable or undrawable. Furthermore, we present a high level algorithm which enables the generation of a concrete diagram from an abstract diagram, whenever it is drawable. Keywords: Euler diagrams; Automatic generation; Drawability; Logic visualization; Data representation | |||
| An extension of UML for the modeling of WIMP user interfaces | | BIBAK | Full-Text | 695-720 | |
| Jesús M. Almendros-Jiménez; Luis Iribarne | |||
| The Unified Modeling Language (UML) [OMG, Unified Modeling Language
Specification, Version 2.0, Technical Report, Object Management Group
<http://www.omg.org/technology/documents/formal/uml.htm>, 2005] provides
system architects working on analysis and design (A&D) with one consistent
language for specifying, visualizing, constructing, and documenting the
artifacts of software systems, as well as for the business modeling. The user
interface (UI), as a significant part of most applications, should be modeled
using UML, and automatic CASE tools may help to generate UIs from UML designs.
In this paper, we describe how to use and specialize UML diagrams in order to
describe the UIs of a software system based on WIMP (Windows, Icons, Menus and
Pointers). Use case diagrams are used for extracting the main UIs. Use cases
are described by means of user-interaction diagrams, a special kind of activity
diagrams in which states represent data output actions and transitions
represent data input events. Input and output interactions in the
user-interaction diagrams help the designer to extract the UI components used
in each UI. We obtain a new and specialized version of the use case diagram for
the UI modeling (called UI diagram) and a class diagram for UI components --
called UI-class diagram. The user-interaction, UI and UI-class diagrams, can be
seen as the UML-based UI models of the system. Finally, UI prototypes can be
generated from UI-class diagrams with CASE tool support. As case study of our
technique, we will describe an Internet book shopping system. Keywords: UML 2.0; Use cases; Model-driven development; User interface modeling; Human-computer interaction | |||
| Assessing the usability of a visual tool for the definition of e-learning processes | | BIBAK | Full-Text | 721-737 | |
| Gennaro Costagliola; Andrea De Lucia; Filomena Ferrucci; Carmine Gravino; Giuseppe Scanniello | |||
| In this paper, we present a usability study aiming at assessing a visual
language-based tool for developing adaptive e-learning processes. The tool
implements the adaptive self-consistent learning object SET (ASCLO-S) visual
language, a special case of flow diagrams, to be used by instructional
designers to define classes of learners through stereotypes and to specify the
more suited adaptive learning process for each class of learners. The usability
study is based on the combined use of two techniques: a questionnaire-based
survey and an empirical analysis. The survey has been used to achieve feedbacks
from the subjects' point of view. In particular, it has been useful to capture
the perceived usability of the subjects. The outcomes show that both the
proposed visual notation and the system prototype are suitable for
instructional designers with or without experience on the computer usage and on
tools for defining e-learning processes. This result is further confirmed by
the empirical analysis we carried out by analysing the correlation between the
effort to develop adaptive e-learning processes and some measures suitable
defined for those processes. Indeed, the empirical analysis revealed that the
effort required to model e-learning processes is not influenced by the
experience of the instructional designer with the use of e-learning tools, but
it only depends on the size of the developed process. Keywords: Adaptive learning processes; e-Learning; Effort estimation; Usability survey; Visual languages | |||