Angela Guercio

Automating visual language generation

A system to generate and interpret customized visual languages in given application areas is presented. The generation is highly automated. The user presents a set of sample visual sentences to the generator. The generator uses inference grammar techniques to produce a grammar that generalizes the initial set of sample sentences, and exploits general semantic information about the application area to determine the meaning of the visual sentences in the inferred language. The interpreter is modeled on an attribute grammar. A knowledge base, constructed during the generation of the system, is then consulted to construct the meaning of the visual sentence. The architecture of the system and its use in the application environment of visual text editing (inspired by the Heidelberg icon set) enhanced with file management features are reported. >

ICON PURITY — TOWARD A FORMAL THEORY OF ICONS

In this paper, we give purity-preserving conditions for iconic operators, and present a formal definition of degree of icon purity by extending an icon system to a fuzzy icon system, based upon the theory of fuzzy sets. We also show an icon system can be modeled by means of an attribute grammar.

Relation grammars and their application to multi-dimensional languages

Relation grammars are introduced as a powerful formalism for specifying the syntax of visual languages and, more generally, of multi-dimensional languages. Textual languages use only the implicit relation of sequential concatenation of symbols. The proposed extension relax this limitation and allows the introduction of any number of relations. By analogy with textual grammars, relation grammars make it easier to recognize the purpose of the lexical analysis phase and that of the syntactic one for parsing multi-dimensional structures.

Relation grammars for modelling multi-dimensional structures

Relation grammars (RGs) are introduced as a possible general framework for specifying the syntax of visual languages and, more generally, of multi-dimensional languages. A formal definition of relation grammars is given. Two examples of applications on graphs are shown. RG formalism is compared to conventional context-free grammars. RGs are used to describe the syntax of horizontal lines and statechart graphs using picture processing grammars and picture layout grammars, respectively.<<ETX>>

An XML-based approach to multimedia software engineering for distance learning

Multimedia Software Engineering (MSE) is a new frontier for both Software Engineering (SE) and Visual Languages (VL). In fact multimedia software engineering can be considered as the discipline for systematic specification, design, substitution and verification of visual patterns. Visual Languages contribute to MSE such concepts as: Visual notation for software specification, design and verification flow charts, ER diagrams, Petri Nets, UML visualization, visual programming languages etc. Multimedia Software Engineering and Software Engineering are like two sides of the same coin. On the one hand we can apply software engineering principles to the design of multimedia systems. On the other hand we can apply multimedia technologies to the software engineering practice. In this paper we concentrate on the first of these possibilities. One of the promising application areas for Multimedia Software Engineering is Distance Learning. One aim of this paper is to demonstrate how it is possible to design and to implement complex multimedia software systems for Distance Learning using a Teleaction Object transformer based on XML technology applying a Component-Based Multimedia Software Engineering approach. The paper shows a complete process of dataflow transformation that represents TAO in different ways (text, TAOML, etc.) and at different levels of abstraction. A component-based tool architecture is also discussed.The use of an XML-based approach in the Distance Learning field has other advantages as well. It facilitates reuse of the teaching resources by using metadata. Standards for representing multimedia distance learning materials are currently evolving. Such standards are necessary in order to allow a representation which is independent of hardware and software platforms so that this material can be examined, for example, in a web browser or so that it may be reused.

Multimedia languages for teleaction objects

A teleaction object (TAO) is a multimedia object with associated hypergraph structure and knowledge structure. The user can create and modify the private knowledge of a TAO so that the TAO will react automatically to certain events. The hypergraph structure supports the effective presentation and efficient communication of multimedia information. TAOs are extremely valuable since they greatly improve the selective access and presentation of relevant multimedia information. Following the ideas of Chang (1996), the authors show how visual languages can be extended to multimedia languages for production of TAOs.

Grammatical inference algorithms for the generation of visual languages

A grammatical inference technique tailored for the definition of the syntax of visual languages is presented. The technique employs a functional similarity measure between icons, the primitives of visual languages. An algorithm based on this technique has been implemented and utilized for the development of the inference module of a system for the automatic generation and use of user-defined visual languages. Experimental results comparing the behaviour of the algorithm with that of Levine [18] are shown. The results suggest the efficacy of the algorithm for the generation of application-specific visual languages.

Addressing Challenges in Web Accessibility for the Blind and Visually Impaired

Searching for relevant information on the web is an important aspect of distance learning. This activity is a challenge for visually impaired distance learners. While sighted people have the ability to filter information in a fast and non sequential way, blind persons rely on tools that process the information in a sequential way. Learning is slowed by screen readers which do not interact well with web pages. This paper introduces WAVES, a tool for the fast retrieval of information in a web page for blind and visually impaired people. The paper describes the WAVES prototype, a system that performs a page restructuring of webpages. The system analyzes webpages, identifies elements of interests from a webpage, evaluates their importance by using semantic information and visual cues, sorts them by importance and uses them to restructure the webpage so that data from the original webpage are presented to the reader in a concise format. A preliminary evaluation test of the prototype system has been performed with a sample set of users. The results of the preliminary test show an increase in speed and accuracy when the WAVES system has been used.

An intelligent iconic system to generate and to interpret visual languages

Using the SIL-Icon compiler, whereby a general-purpose iconic system is specialized by expert provision of domain-specific grammar and semantics to define the individual visual language, a learning interface module (LIM) has been designed allowing the nonexpert user to utilize the system and define his or her own visual language providing only sample sentences from which the LIM autonomously constructs the domain-specific aspects of the language. A brief description of the SIL-Icon compiler is presented. An overview is given of the whole learning iconic system, and all the principal concepts and modules are detailed.<<ETX>>

A visual editor for multimedia application development

Multimedia applications are becoming increasingly important in areas such as education (digital libraries, training, presentation, distance learning), health care (telemedicine, health information management, medical image systems), entertainment (video-on-demand, music databases, interactive TV), information dissemination (news-on-demand, advertising, TV broadcasting), and manufacturing (distributed manufacturing, distributed collaborative authoring). In this paper we introduce a visual software engineering tool which is part of a suite of tools called MICE used for the rapid prototyping of distributed multimedia applications.