Developing applications that make effective use of machine-readable knowledge sources as promised by the Semantic Web vision is attracting much of current research interest; this v...
Abstract. We study the complexity of consistency checking and query answering on incomplete databases for languages ranging from non-recursive Datalog to disjunctive Datalog with n...
Abstract. This paper presents a decidable fragment for combining ontologies and rules in order-sorted logic programming. We describe ordersorted logic programming with sort, predic...
We address the problem of answering conjunctive queries over knowledge bases, specified by sets of first-order sentences called tuple-generating dependencies (TGDs). This problem i...
: This paper formalizes UML class diagrams and structural patterns as mathematical objects and provides a precise notion of conformance of a structural model specified as a class d...