We present the framework of ontology-based data access, a semantic paradigm for
providing a convenient and user-friendly access to data repositories, which has been …

Abstract Information systems have to deal with an increasing amount of data that is
heterogeneous, unstructured, or incomplete. In order to align and complete data, systems …

Recent years have seen an increasing interest in ontology-mediated query answering, in
which the semantic knowledge provided by an ontology is exploited when querying data …

We discuss the use of various temporal knowledge representation formalisms for ontology-
mediated query answering over temporal data. In particular, we analyse ontology and query …

In contrast to qualitative linear temporal logics, which can be used to state that some
property will eventually be satisfied, metric temporal logics allow us to formulate constraints …

We aim to determine which temporal instance queries can be uniquely characterised by a
(polynomial-size) set of positive and negative temporal data examples. We start by …

Context-aware systems use data collected at runtime to recognize certain predefined
situations and trigger adaptations. This can be implemented using ontology-based data …

We investigate ontology-based data access to temporal data. We consider temporal
ontologies given in linear temporal logic LTL interpreted over discrete time (Z,<). Queries are …

Aiming at ontology-based data access to temporal data, we design two-dimensional
temporal ontology and query languages by combining logics from the (extended) DL-Lite …

We study access to temporal data with TEL, a temporal extension of the tractable description
logic EL. Our aim is to establish a clear computational complexity landscape for the atomic …