S. Ceri

Specification and implementation of exceptions in workflow management systems

Although workflow management systems are most applicable when an organization follows standard business processes and routines, any of these processes faces the need for handling exceptions, i.e., asynchronous and anomalous situations that fall outside the normal control flow.nIn this paper we concentrate upon anomalous situtations that, although unusual, are part of the semantics of workflow applications, and should be specified and monitored coherently; in most real-life applications, such exceptions affect a significant fraction of workflow cases. However, very few workflow management systems are integrated with a highly expressive language for specifying this kind of exception and with a system component capable of handling it.n We present Chimera-Exc, a language for the specification of exceptions for workflows based on detached active rules, and then describe the architecture of a system, called FAR, that implements Chimera-Exc and integrates it with a commercial workflow management system and database server. We discuss the main issues that were solved by our implementation, and report on the performance of FAR. We also discuss design criteria for exceptions in light of the formal properties of their execution. Finally, we focus on the portability of FAR on its unbundling to a generic architecture with detached active rules.

Search Computing

“Who are the strongest European competitors on software ideas? Who is the best doctor to cure insomnia in a nearby hospital? Where can I attend an interesting conference in my field close to a sunny beach?” This information is available on the Web, but no software system can accept such queries nor compute the answer. We hereby propose search computing as a new multi-disciplinary science which will provide the abstractions, foundations, methods, and tools required to answer these and many similar queries. While state-of-art search systems answer generic or domain-specific queries, search computing enables answering questions via a constellation of dynamically selected, cooperating search services. Search computing requires innovation in software principles, languages, interfaces and protocols, as well as contributions from other sciences such as mathematics, operations research, psychology, sociology, economical and legal sciences.

WebML and Glue: An Integrated Discovery Approach for the SWS Challenge

In this paper we describe the improvements on our approach to the old discovery scenario of the SWS Challenge and our current solution for the new discovery and composition scenario. The mediation scenario is not included in this paper since there were no changes to it from the edition of the SWS Challenge workshop in Athens. The solution proposed is based on the WebML design methodology and the Glue WSMO discovery engine.