In the last few years the field of logic-based knowledge representation took a lot of
inspiration from database theory. A vital example is that the finite model semantics in …

Recently, the field of knowledge representation is drawing a lot of inspiration from database
theory. In particular, in the area of description logics and ontology languages, interest has …

We propose a novel use of ontologies to aid the on-demand design of data-centric systems.
By means of a process that we call focusing, a schema for a (possibly knowledge-enriched) …

We study the problem of finite ontology mediated query answering (FOMQA), the variant of
OMQA where the represented world is assumed to be finite, and thus only finite models of …

We study the description logic SQ with number restrictions applicable to transitive roles,
extended with either nominals or inverse roles. We show tight 2EXPTIME upper bounds for …

Abstract Reasoning with existential rules typically consists of checking whether a Boolean
conjunctive query is satisfied by all models of a first-order sentence having the form of a …

We investigate the problem of finite entailment of ontology-mediated queries. We consider
the expressive query language, unions of conjunctive regular path queries (UCRPQs) …

We study the problem of finite entailment of ontology-mediated queries. Going beyond local
queries, we allow transitive closure over roles. We focus on ontologies formulated in the …

We investigate the decidability and computational complexity of query conservative
extensions in Horn description logics (DLs) with inverse roles. This is more challenging than …

We investigate reasoning and query answering in expressive domain knowledge bases
(KBs) that are in OWL 2 Full and contain large individual data sets. For this, we introduce Hi …