Logic Programming And Nonmonotonic Reasoning: 9th International Conference, Lpnmr 2007, Tempe, Az, Usa, May 15-17, 2007. Proceedings

Lecture Notes in Artificial Intelligence Edited by J. G. Carbonell and J. Siekmann Subseries of Lecture Notes in Computer Science 4483 Chitta Baral Gerhard Brewka John Schlipf (Eds.) Logic Programming and Nonmonotonic Reasoning 9th International Conference, LPNMR 2007 Tempe, AZ, USA, May 15-17, 2007 Proceedings 13 Series Editors Jaime G. Carbonell, Carnegie Mellon University, Pittsburgh, PA, USA Jörg Siekmann, University of Saarland, Saarbrücken, Germany Volume Editors Chitta Baral Arizona State University, Department of Computer Science and Engineering Box 875406, Tempe, AZ 85287-5406, USA E-mail: [email protected] Gerhard Brewka University of Leipzig, Department of Computer Science Postfach 100920, 04009 Leipzig, Germany E-mail: [email protected] John Schlipf University of Cincinnati, Department of Computer Science 892 Rhodes Hall, Cincinnati, OH 45221-0030, USA E-mail: [email protected] Library of Congress Control Number: 2007925046 CR Subject Classification (1998): I.2.3-4, I.2, F.4.1, D.1.6 LNCS Sublibrary: SL 7 – Artificial Intelligence ISSN ISBN-10 ISBN-13 0302-9743 3-540-72199-1 Springer Berlin Heidelberg New York 978-3-540-72199-4 Springer Berlin Heidelberg New York This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, re-use of illustrations, recitation, broadcasting, reproduction on microfilms or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer. Violations are liable to prosecution under the German Copyright Law. Springer is a part of Springer Science+Business Media springer.com © Springer-Verlag Berlin Heidelberg 2007 Printed in Germany Typesetting: Camera-ready by author, data conversion by Scientific Publishing Services, Chennai, India Printed on acid-free paper SPIN: 12056606 06/3180 543210 Preface These are the proceedings of the Ninth International Conference on Logic Programming and Nonmonotonic Reasoning (LPNMR 2007). LPNMR is a forum for exchanging ideas on declarative logic programming, nonmonotonic reasoning, and knowledge representation. LPNMR encompasses theoretical studies, design and implementation of logic-based programming languages and database systems, and development of experimental systems. LPNMR 2007 was held in Tempe Arizona, USA, May 15–17, 2007, with workshops on May 14. Previous conferences were organized in Washington D.C., USA