International Journal of Cooperative Information Systems

In this paper, one of the informally described models of agent cooperation (Jennings, 1995) has been used to develop and formally specify a generic model of a cooperative agent (GCAM). The compositional development method for multi-agent systems DESIRE supported the principled design of this model of cooperation. To illustrate reusability of the generic model, two application domains have been addressed: collaborative engineering design, and Call Center support.

Agent technologies have steadily matured in moving from the research laboratory to industrial application over the last ten years. Numerous systems have been deployed or are under advanced development with strong industrial support. These systems suggest important lessons for both industry and researchers. From an industrial perspective, these examples reflect trends in both business and technology that make agents an increasingly attractive commercial tool. From a research perspective, these examples identify important gaps in agent technology that merit the attention of academicians.

A platform for performing multi-agent searches in heterogeneous digital libraries is proposed. This differs significantly from previous approaches by completely removing the concept of a centralized search engine. Specifically, the organization of information held on domain index servers is constrained to conform to a virtual tree representation based on facets and global keyword concept schema particular to the set of information providers associated with the domain of interest (e.g. preparatory intranet). Simulation studies are used to compare this platform against a digital library platform presently in use, which employs the traditional central server scheme. Improvements in terms of query service time and robustness are demonstrated.

The large quantity and often questionable quality of available information in the information age provides a shaky foundation for decision making by individuals and organizations alike. This has created a tremendous demand for information services which can access, filter, process and present information on an as-needed basis. However, two factors complicate the design of such information services, namely the distributed and the autonomous nature of data sources.

This paper reports on the design and implementation of a generic architecture for supporting information services, which meets the above challenge. The architecture adopts concepts from conceptual modeling to offer a transparent description of the information sources' setting and uses active databases techniques to offer a declarative, event-based language for defining coordination rules for integrating distributed information services. Accordingly, the proposed architecture supports two of the most prominent utilities of information services, namely the pre-designed flow of operations and the reactive provision of information.

In addition to describing the architecture and illustrating its features with an example, the paper presents a prototype implementation and reports on some experimental performance results.

This paper reviews the growing interest in an integrated construction project model, and examines the fundamental concept of an integrated project model by discussing the various definitions that have evolved as well as the various approaches to its development. The nature of collaborative communications that the integrated project model needs to support is also discussed, as are the enabling information and communications technologies that may have a role in the realization of the model. The paper concludes with some thoughts on the future development of the integrated construction project model.

A multidatabase system (MDBS) integrates information from multiple pre-existing local databases. A major challenge for global query optimization in an MDBS is that some required local information about local database systems such as local cost models may not be available at the global level due to local autonomy. A feasible method to tackle this challenge is to group local queries on a local database system into classes and then use the costs of sample queries from each query class to derive a cost formula for the class via regression analysis. This paper discusses the issues on how to classify local queries so that a good cost formula can be derived for each query class. Two classification approaches, i.e. bottom-up and top-down, are suggested. The relationship between these two approaches is discussed. Classification rules that can be used in the approaches are identified. Problems regarding composition and redundancy of classification rules are studied. Classification algorithms are given. To test the membership of a query in a class, an efficient algorithm based on ranks is introduced. In addition, a hybrid classification approach that combines the bottom-up and top-down ones is also suggested. Experimental results demonstrate that the suggested query classification techniques can be used to derive good local cost formulas for global query optimization in an MDBS.