Joachim Peer

A PDDL Based Tool for Automatic Web Service Composition

One of the motivations for research in semantic web services is to automatically compose web service operations to solve given problems. The idea of using AI planning software to this end has been suggested by several papers. The present paper follows this approach but argues that the diversity of the web service domains is best addressed by a flexible combination of complementary reasoning techniques and planning systems. We present a tool that transforms web service composition problems into AI planning problems and delegates them to the planners most suitable for the particular planning task. The tool uses PDDL, a language supported by a wide range of planning engines, as a transfer format. The present paper describes the tool and its strategies to cope with the problems of incomplete information, various types of web service indeterminism, stateful services and structurally rich goal specifications.

Bringing Together Semantic Web and Web Services

There are two major ongoing efforts to advance the World Wide Web. On one side there is the Semantic Web research, on the other side is the Web Service research. Both activities aim to make content on the web accessible and usable not only for humans but also for machines in order to create a foundation for intelligent automated services and business processes. These two efforts are highly complementary, and there is work in progress towards a unification of them. This paper contributes to this process of unification by presenting a method of connecting Web Services descriptions with Semantic Web ontologies.

Semantic web policies – a discussion of requirements and research issues

Policies are pervasive in web applications. They play crucial roles in enhancing security, privacy and usability of distributed services. There has been extensive research in the area, including the Semantic Web community, but several aspects still exist that prevent policy frameworks from widespread adoption and real world application. This paper discusses important requirements and open research issues in this context, focusing on policies in general and their integration into trust management frameworks, as well as on approaches to increase system cooperation, usability and user-awareness of policy issues.

A POP-Based replanning agent for automatic web service composition

This paper illustrates how a modified version of a modern Partial Order Planner (POP) can be combined with a replanning algorithm to solve planning problems in Web service domains. The contributions of the work are (i) a method of using feedback gained from plan execution for improving plan search and (ii) a novel approach of dealing with nondeterministic Web service operations.