Exploiting conjunctive queries in description logic programs

摘要: Towards combining rules and ontologies for the Semantic Web, nonmonotonic Description Logic Programs (dl-programs) have been proposed as a powerful formalism to couple logic programming reasoning on clear semantic basis. In this paper, we present cq-programs, which enhance dl-programs with conjunctive queries (CQ) union of (UCQ) over Logics knowledge bases, well disjunctive rules. The novel has two advantages. First, it offers increased expressivity because allows (U)CQs in bodies allow one access unnamed individuals they increase formalism, evident from complexity NEXP 2-EXP. And second, when implemented combination between system DL-reasoner, integration gives rise strategies optimizing calls by exploiting specific support (U)CQs. To end, equivalence preserving transformations can be used program rewriting, respective generic rewriting algorithms. Experimental results cq-program prototype show that lead significant performance improvements, suggest cq-programs provide useful basis dl- optimization.