HYPERMEDIA, INFORMATION SYSTEMS AND ORGANIZATIONS: A RESEARCH AGENDA

Although hypermedia systems are becoming more sophisticated and readily available as of thee shelf products, there are few hypermedia applications within business and industrial organizations. This paper argues that this phenomena is rooted in the concept of hypermedia applications as standalone programs. Larger acceptance of hypermedia within organizations will occur once this technology is better integrated with other organizational systems and applied to carefully selected tasks. The paper identifies three areas for research in this context: the tasks perspective, which deals with selecting tasks for which to develop hypermedia applications, the knowledge perspective, which deals with representing and managing the knowledge processed by organizations, and the integration perspective, which deals with technical issues in software integration. This paper suggests that solutions to the problems presented will prompt the acceptance of hypermedia technology within organizations.Information Systems Working Papers Serie

DISTRIBUTED DESIGN OF HYPERMEDIA APPLICATIONS

Hypermedia technology is experiencing a rapid growth due, in large part, to the WWW. Many hypermedia applications, especially those on the WWW have a distributed design besides being physically spread among many servers. A distributed design is a design that varies, albeit slightly, from instance to instance. However, such design variances can lead to undesirable inconsistencies that can render a hypermedia application useless. This paper explores this problem and presents a solution based on a methodological approach to hypermedia design and construction. The methods are illustrated via a sample applicationInformation Systems Working Papers Serie

CAN WE TRANSFORM LOGIC PROGRAMS INTO ATTRIBUTE GRAMMARS?

In this paper we study the relationship between Attribute Grammars and Logic Programs, concentrating on transforming logic programs into attribute grammars. This has potential applications in compilation techniques for logic programs. It does not seem possible to transform arbitrary Logic Programs into Attribute Grammars, basically because the same logic variables can sometimes be used as input and sometimes as output. We introduce the notion of an Abstract Attribute Grammar, which is similar to that of an Attribute Grammar with the exception that attributes are not classified into inherited and synthesized, and that the semantic equations are replaced by restriction sets. These sets represent a restriction on the values of attribute occurrences namely, all elements within each set have to be equal. We give an effective translation schema which produces an equivalent Abstract Attribute Grammar for a given Logic Program. We provide a formal proof of this equivalence. We then proceed to classify a class of Abstract Attribute Grammars that can be transformed into Attribute Grammars, and show how to achieve this transformation. By composing both transformations one can transform certain logic programs into attribute grammars. Complete proofs ar5e given.Information Systems Working Papers Serie

MALUAR - A COMPUTATIONAL HYPERTEXT ENVIRONMENT

Information Systems Working Papers Serie

METHODOLOGIES FOR DESIGNING AND DEVELOPING HYPERMEDIA APPLICATIONS

Hypermedia design, as any other design activity, may be observed according to two points of view: methods which suggest milestones to guide the designer's work and process which concerns the actual detailed behavior of the designer at work. Cognitive studies assess that mental processes involved in any design process show widely shared human characteristics regardless to the used design method. Thereby, they provide general keys to help designers. Thus, a hypertext design environment should equally consider the two dimensions of a hypertext design activity, in particular it should support the natural design process specificities, mainly the incremental and opportunist aspects. The paper focuses on the hypertext design as a computer supported human activity. It examines what is general both in the design methods and in the design process of hypertexts in order to determine which general features are helpful to designers. This analysis has raised from the observation of the behavior of MacWeb users during design tasks. It is related to sound and well known results in cognitive science. The paper also describes how the proposed features are implemented in the MacWeb system.Information Systems Working Papers Serie

TEXT EDITING AND BEYOND: A STUDY IN LOGIC MODELING

This paper presents a logic modeling exercise in which we develop test and implement a logic model for a test editor and use it to test existing test editing software. We begin by presenting a first order Horn logic axiomatization of a text editor by providing domain equations for the primitive operations insert, delete and character retrieval. We show that this logic model captures the essential aspects of the text editing task and how more complex features are built using these primitives. We discuss possible implementations and conclude that any operational semantics - the set of algorithms that perform the task - must be strongly related to the logic model we present. In other words, each operational semantics constitutes a model of the logic theory Next, we illustrate the usefulness of the model by implementing a basic text editing system and testing the correctness of an existing text editor. We conclude by describing how we are integrating these modeling techniques into a larger and more complex knowledge-based system.Information Systems Working Papers Serie

ON THE SEMANTICS OF TRANSACTION TIME AND VALID TIME IN BITEMPORAL DATABASES

Numerous proposals for extending the relational data model to incorporate the temporal dimension of data have appeared in the past several years. While most of these have been historical databases, incorporating in some fashion a valid time dimension to the data model and the query languages, others have been rollback databases, incorporating a transaction time dimension, or bitemporal databases, incorporating both of these temporal dimensions. In this paper we address an issue that has been lacking in many of these papers, namely, a formal specification of the precise semantics of these temporal dimensions of data. We introduce the notion of reference time - the time that any operation is applied to the database state - and provide a logical analysis of the interrelationships among these three temporal dimensions. We also provide an analysis of the meaning of various variables such as now and â which have been used in many of these models without a complete specification of their semantics.Information Systems Working Papers Serie

RMCASE: COMPUTER-AIDED SUPPORT FOR HYPERMEDIA DESIGN AND DEVELOPMENT

We present the design of a computer-aided environment, RMCase, to support the design and construction of hypermedia applications. The environment is based upon the Relationship Management methodology. MCase supports hypermedia design and development activities. Support for cognitive design processes is achieved through three fundamental premises that form the foundation of RMCase: (1) fluid feedback loops between the various methodological stages, (2) manipulation of objects at the instance level, and (3) lightweight prototyping . To achieve this, RMCase itself is designed as a hypermedia application, where hypertextual navigation implements feedback loops. Instance objects can be cloned and abstraction/instantiation mechanisms are envisioned to facilitate designers back and forth movements between the abstract and the concrete layers of an application. As a result, RMCase will support bottom-up, top-down and middle-out software development styles.Information Systems Working Papers Serie

BRIDGE LAWS IN HYPERTEXT: A LOGIC MODELING APPROACH

Increasingly, computerized systems tend to delegate certain portions of their functionality to other systems. This is routinely done by systems that use Data Base Management Systems (DBMS) to manage their data. The DBMS is in charge of all data related operations. A similar phenomena is emerging in the area of graphical user-interfaces. As more of these delegation phenomena occur, the establishment of flexible communication channels for the different applications becomes increasingly important. We propose to achieve this communication by establishing a set of relationships between the applications. These relationships will be specified by bridge laws, i.e. laws that establish bridges between different domains. We concentrate on a particular example: coupling arbitrary applications to a hypertext user interface. In terms of the discussion above, one of the systems in consideration is fixed. We study the elements that are needed in order to establish effective bridge laws. We do this by defining a general framework and providing two examples. The first example deals with a Data Base Management System, and the second one with a model management system. The examples show that in order to achieve effective interaction between a system and a hypertext interface, some meta-knowledge is required. We extrapolate from our experiments to conclude the type of general properties of bridge laws that are necessary to achieve this high level type of process communication.Information Systems Working Papers Serie