| Introduction | | BIB | Full-Text | 1-3 | |
| Usable adaptive hypermedia systems | | BIBAK | Full-Text | 5-29 | |
| T. Tsandilas; M. C. Schraefel | |||
| Adaptive interfaces have received much criticism because adaptation and
automatic assistance generally contradict the principles of direct-manipulation
interfaces. In addition, their success depends highly on the ability of user
models to capture the goals and needs of the users. As the construction of user
models is often based on poor evidence, even the most advanced learning
algorithms may fail to infer accurately the user goals. Previous research has
put little emphasis on investigating usability problems of adaptive systems and
developing interaction techniques that could resolve these problems. This paper
examines these problems and presents an interaction model for adaptive
hypermedia (AH) that merges adaptive support and direct manipulation. This
approach is built upon a new content adaptation technique that derives from
fisheye views. This adaptation technique supports incremental and continuous
adjustments of the adaptive views of hypermedia documents and balances between
focus and context. By combining this technique with visual representations and
controllers of user models, we form a twofold interaction model that enables
users to move quickly between adaptation and direct control. Two preliminary
user studies exhibit the strengths of our proposed interaction model and
adaptation technique. Future extensions to our work are outlined based on the
weaknesses and limitations that the studies revealed. Keywords: Adaptive hypermedia, Usability, Predictability, User control, Focus+context,
Fisheye views | |||
| Enhancing the adaptivity of an existing Website with an epiphyte recommender system | | BIBAK | Full-Text | 31-52 | |
| Bruno Richard; Pierre Tchounikine | |||
| In this paper we propose an approach to enhance the adaptivity of an
existing Website by plugging on top of it ("epiphyte approach") a recommender
system that displays additional tips and functionalities in a separate window.
The recommender system analyzes the way the user browses through the Website
according to predefined prototypical ways of using the Website ("models of
use") and then proposes information or functionalities that appear useful
according to this model of use. Different models of use can be identified, each
of them corresponding to a "logical extension" of the original Website.
Associating an existing Website with such logical extensions therefore allows
enhancing its adaptivity whilst (i) not modifying the original Website and (ii)
facilitating the evolution of the adaptive features as this only requires
modifying the recommender system. This approach can be used as an alternative
and/or in association with other approaches related in the literature. Keywords: Web, Recommender systems, Adaptive hypermedia sysytems, Models of use | |||
| Embedding information retrieval in adaptive hypermedia: IR meets AHA! | | BIBAK | Full-Text | 53-76 | |
| Lora Aroyo; Paul De Bra; Geert-Jan Houben; Richard Vdovjak | |||
| This paper concentrates on the retrieval aspect in adaptive hypermedia (AH).
Traditionally, AH research concentrates on applications that are 'closed', in
the sense that they assume fixed content elements. Certain applications ask for
an extension of the contents considered, with data obtained through information
retrieval (IR). This paper addresses this issue of 'opening up' AH
applications, and gives insight into research that applies techniques from IR
and from the Semantic Web (SW) for the embedding of IR in AH. We look at this
issue in the context of an abstract reference model (AHAM) and a concrete
implementation framework (AHA!). The goal of this research is to define a
framework for AH with extended IR functionality. We address the relevant issues
for this framework, characterized by the application of concepts from the SW
paradigm leading to an enriched notion of concept relevancy. Keywords: Adaptive hypermedia, Information retrieval, Ontology, Semantic Web, Metadata | |||
| A logical characterization of adaptive educational hypermedia | | BIBAK | Full-Text | 77-113 | |
| Nicola Henze; Wolfgang Nejdl | |||
| Currently, adaptive educational hypermedia systems (AEHSs) are described
using nonuniform methods, depending on the specific view of the system, the
application, or other parameters. There is no common language for expressing
the functionality of AEHSs, hence these systems are difficult to compare and
analyze. In this paper we investigate how a logical description can be employed
to characterize adaptive educational hypermedia. We propose a definition of
AEHSs based on first-order logic, characterize some AEHSs resulting from this
formalism, and discuss the applicability of this approach. Keywords: Adaptive hypermedia, User modeling, Semantic Web, Adaptive Web, Educational
hypermedia | |||
| Introduction | | BIB | Full-Text | 115-126 | |
| Taking control of web browsing | | BIBAK | Full-Text | 127-140 | |
| Vicki L. Hanson | |||
| Adherence to accessibility guidelines for Web pages does not necessarily
guarantee a usable or satisfying Web experience for all persons with
disabilities. The needs of many of these individuals fall outside the
guidelines for accessible content that most Web authors take into
consideration. Many of these users wish, for example, that they simply could
'enlarge' what is on a Web page. They also express the wish that pages would be
'less confusing'. To meet these needs, Web browsers and various software
applications provide for a variety of ways in which page presentations can be
altered. The effects of these alterations often have unexpected consequences.
Some designs accommodate these alterations better than others. This article
discusses one such application that allows users to control features of Web
page presentation and explores design features that facilitate such control. Keywords: Web accessibility, Usability, Design | |||
| Automated interpretation and accessible presentation of technical diagrams for blind people | | BIBA | Full-Text | 141-163 | |
| M. Horstmann; M. Lorenz; A. Watkowski; G. Ioannidis; O. Herzog; A. King; D. G. Evans; C. Hagen; C. Schlieder; A.-M. Burn; N. King; H. Petrie; S. Dijkstra; D. Crombie | |||
| The EU-supported TeDUB (Technical Drawings Understanding for the Blind) project is developing a software system that aims to make technical diagrams accessible to blind and visually impaired people. It consists of two separate modules: one that analyses drawings either semi-automatically or automatically, and one that presents the results of this analysis to blind people and allows them to interact with it. The system is capable of analysing and presenting diagrams from a number of formally defined domains. A diagram enters the system as one of two types: first, diagrams contained in bitmap images, which do not explicitly contain the semantic structure of their content and thus have to be interpreted by the system, and second, diagrams obtained in a semantically enriched format that already yields this structure. The TeDUB system provides blind users with an interface to navigate and annotate these diagrams using a number of input and output devices. Extensive user evaluations have been carried out and an overall positive response from the participants has shown the effectiveness of the approach. | |||
| Accessible e-learning material: a no-frills avenue for didactical experts | | BIBAK | Full-Text | 165-180 | |
| V. Mirabella; S. Kimani; S. Gabrielli; T. Catarci | |||
| Different organizations adopt accessibility for various and diverse reasons.
Interesting and inspiring as such reasons may be, it is important to ensure
that the motivation for supporting accessibility is that it is the right thing
to do, i.e. a commitment to the provision of equal opportunities for accessing
resources for people with special needs. Among the various efforts for
supporting the development of accessible e-learning material, most of them
propose guidelines that prevalently address technical accessibility issues
(such as the format and navigation of learning material) with little or no
consideration for the didactical experts, and thus their didactical experience,
in developing learning material. Moreover, the aforementioned guidelines tend
to provide generic indications on alternative forms of didactical content for
equivalent access to it. None the less, the sole provision of equivalent forms
does not guarantee the retention of desirable user interface aspects and may
therefore have a negative impact on learning effectiveness. While this paper
acknowledges the role of such guidelines, it does propose that the didactical
experts be provided with a non-technical recourse, improving their development
of accessible e-learning content. By tapping into the experience of the
didactical experts, this work provides them with an avenue leading to enhance
the accessibility of e-learning material. Keywords: Accessibility, E-learning, No-frills, Didactical experts | |||
| Supporting accessible hypermedia in web-based educational systems: defining an accessibility application profile for learning resources | | BIBA | Full-Text | 181-197 | |
| P. Karampiperis; D. Sampson | |||
| The design and development of web-based educational systems for people with special abilities have recently attracted the attention of the research community. However, although a number of systems that claim to meet accessibility needs and preferences are proposed, most of them are typically supported by hypermedia and multimedia educational content that is specially designed for the user targeted group. Such approaches prevent their user groups (both learners and their tutors) from accessing other available resources. Therefore, it is important to be able to built generic e-learning systems that would allow the reuse of existing learning resources in different accessibility demanding applications. To this end, in this article we propose a methodology for defining an accessibility application profile that captures the accessibility properties of learning objects in a standard form and we examine its application to the IEEE Learning Object Metadata (LOM) standard. | |||
| Accessing Egypt: making myths and producing web sites in cyber-Cairo | | BIBA | Full-Text | 199-219 | |
| M. A. Peterson; I. Panovic | |||
| From an anthropological viewpoint, "accessibility" is not so much a technological and design project as it is a cultural construction, a cognitive schema through which graphic designers and technologists imagine audiences and create appropriate graphic designs that will be "accessible" to that audience. The ethnographer's task is the specification of key actors, institutions and discourses active in the making and remaking of accessibility in a given context. In this article, we examine how Egyptian Web producers at the turn of millennium (1999-2001) sought to design Web portals that would allow the "typical" Egyptian to easily access the World Wide Web. We argue, first, that Egyptian Web producers are deeply influenced by national and international discourses that frame IT as a national mission for socioeconomic development. Second, we found that in the absence of clear definitions of the Web audience, Web producers imagined a "typical" Egyptian that contradicted their own experiences of users of the Web. Finally, we found that Egyptian Web producers largely borrowed pre-existing models, using design elements to "inflect" their sites with an Egyptian motif. However, the conceptual models of access and related design strategies created by Egyptian Web producers were out of touch with Egyptian social realities, contributing to a collapse of most Web portal projects. | |||