The Semantic Web is a major endeavor aiming at enriching the existing Web with meta-data and processing methods so as to provide web-based systems with advanced (so-called intelligent) capabilities, in particular with context-awareness and decision support.

The advanced capabilities striven for in most Semantic Web application scenarii primarily call for reasoning. Reasoning capabilities are offered by Semantic Web languages currently developped such as BPEL4WS, BPML, ConsVISor, DAML-S, JTP, Triple, and others. These languages, however, are developed mostly from functionality centered (e.g. ontology reasoning or access validation) or application centered (e.g. Web service retrieval and composition) perspectives. A perspective centered on the reasoning techniques (e.g. forward or backward chaining, tableau-like methods, constraint reasoning, etc.) complementing the above-mentioned activities appears desirable for Semantic Web systems and applications. The workshop is devoted to such a perspective.

Like the current Web is inherently heterogeneous in data formats and data semantics, the Semantic Web will be inherently heterogeneous in its reasoning forms. Indeed, any single form of reasoning turns out irrealistic in the Semantic Web. E.g. ontology reasoning in general relies on monotonic negation (for the meta-data often can be fully specified), while databases, Web databases, and Web-based information systems call for non-monotonic reasoning (for one would not specify in a railways timetable non-existing trains); constraint reasoning is needed in dealing with time (for time intervals are to be dealt with), while (forward and/or backward) chaining is the reasoning of choice in coping with database-like views (for views i.e. virtual data can be derived from actual data by operations such as join and projections).

The workshop on "Principle and Practice of Semantic Web Reasoning'' will be a forum for discussing various forms of reasoning that are or can be used on the Semantic Web. The workshop will address both, reasoning methods for the Semantic Web and Semantic Web applications relying upon various forms of reasoning.

The first workshop in this series took place in 2003 in Mumbai.

Topics of interest include:
Rule markup languages
Constraint reasoning on the Semantic Web
Default reasoning on the Semantic Web
Fuzzy reasoning on the Semantic Web
Inconsistency-tolerant reasoning on the Semantic Web
Reasoning and querying on the Web
Reasoning methods for Adaptive Web systems and applications
Reasoning methods for Web-based decision support
Reasoning methods for policy specification and conformance

Important dates:
Submission deadline: May 15, 2004, Notification to authors: June 12, 2004, Camera-ready version: June 26, 2004.

Workshop Coordination
Hans Jurgen Ohlbach, (program chair) ohlbach@informatik.uni-muenchen.de
Sebastian Schaffert, (proceedings chair) schaffert@informatik.uni-muenchen.de

Programm committee:
Francois Bry, University of Munich, Germany
Francois Fages, INRIA Rocquencourt, France
Enrico Franconi, Free University of Bozen-Bolzano, Italy
Georg Gottlob, University of Vienna, Austria
Benjamin Grosof MIT Sloan School of Management,
Carsten Lutz, Dresden University of Technology, Germany
Nicola Henze, University of Hannover, Germany
Massimo Marchiori, W3C and University of Venice, Italy
Hans Jurgen Ohlbach, University of Munich, Germany
Sebastian Schaffert, University of Munich, Germany
Michael Schroder, Dresden University of Technology, Germany
Gerd Wagner, Eindhoven University of Technology, Netherlands
Howard Williams, Heriot-Watt University, Edinburgh, Scotland
Guizhen Yang, University at Buffalo, New York, USA

Submission Guidelines:
The proceedings of PPSWR'04 will be published by Springer in the Lecture Notes in Computer Science (LNCS). For instructions on the LNCS format, see http://www.springer.de/comp/lncs/authors.html.
Submissions must be formatted according to LNCS rules, and submitted electronically as PDF or Postscript at the submission system at https://lehre.pms.ifi.lmu.de/ppswr04/ Two submission categories are accepted for the PPSWR'04:

Full papers: 10 - 15 pages
Short papers: 3 - 5 pages