Concrete domains, especially those that allow to compare features with numeric values, have long been recognized as a very desirable extension of description logics (DLs), and significant efforts have been invested into adding them to usual DLs while keeping the complexity of reasoning in check.
Our main result is to show that every query in this non-monotonic query language can be translated in polynomial time into Datalog with negation under the stable model semantics.
In ontology-based data access (OBDA), ontologies have been successfully employed for querying possibly unstructured and incomplete data.
In this paper, we consider the setting of graph-structured data that evolves as a result of operations carried out by users or applications.
Two-way regular path queries (2RPQs) have received increased attention recently due to their ability to relate pairs of objects by flexibly navigating graph-structured data.
In order to meet usability requirements, most logic-based applications provide explanation facilities for reasoning services.