09441 Abstracts Collection -- The Constraint Satisfaction Problem: Complexity and Approximability

From 25th to 30th October 2009, the Dagstuhl Seminar 09441 ``The Constraint Satisfaction Problem: Complexity and Approximability\u27\u27 was held in Schloss Dagstuhl~--~Leibniz Center for Informatics. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available

Managing data through the lens of an ontology

Ontology-based data management aims at managing data through the lens of an ontology, that is, a conceptual representation of the domain of interest in the underlying information system. This new paradigm provides several interesting features, many of which have already been proved effective in managing complex information systems. This article introduces the notion of ontology-based data management, illustrating the main ideas underlying the paradigm, and pointing out the importance of knowledge representation and automated reasoning for addressing the technical challenges it introduces

Completeness of resolution revisited

AbstractBy a novel argument we prove the completeness of (ground) resolution. The argument allows us to give the completeness proofs for various strategies of resolution in a uniform way, thus contributing to the insight into these strategies. For example, our exposition shows how the more efficient strategies can be derived from an analysis of the redundancies in the completeness proofs. Moreover, by using Zorn's Lemma in dealing with infinite sets of ground clauses, we obtain completeness proofs which are completely independent of the cardinality of both the language and the set of clauses. We discuss the set theoretic status of these results