TY - CHAP T1 - Information Gathering During Planning for Web Service Composition T2 - The Semantic Web – ISWC 2004 Y1 - 2004 A1 - Kuter,Ugur A1 - Sirin,Evren A1 - Nau, Dana S. A1 - Parsia,Bijan A1 - Hendler,James ED - McIlraith,Sheila ED - Plexousakis,Dimitris ED - van Harmelen,Frank KW - Computer science AB - Hierarchical Task-Network (HTN) based planning techniques have been applied to the problem of composing Web Services, especially when described using the OWL − S service ontologies. Many of the existing Web Services are either exclusively information providing or crucially depend on information-providing services. Thus, many interesting service compositions involve collecting information either during execution or during the composition process itself. In this paper, we focus on the latter issue. In particular, we present ENQUIRER , an HTN-planning algorithm designed for planning domains in which the information about the initial state of the world may not be complete, but it is discoverable through plan-time information-gathering queries. We have shown that ENQUIRER is sound and complete, and derived several mathematical relationships among the amount of available information, the likelihood of the planner finding a plan, and the quality of the plan found. We have performed experimental tests that confirmed our theoretical results and that demonstrated how ENQUIRER can be used in Web Service composition. JA - The Semantic Web – ISWC 2004 T3 - Lecture Notes in Computer Science PB - Springer Berlin / Heidelberg VL - 3298 SN - 978-3-540-23798-3 UR - http://www.springerlink.com/content/v829m5080fc0bpng/abstract/ ER -