Ontology engineering and novel reasoning services

Ontologies are developed as logical theories capturing domain knowledge, and used in a variety of applications, most prominently in clinical and life sciences. They are used to design and maintain terminologies, to base information systems on, and to provide flexible access to data. Recent standardization of computer processable ontology languages, in particular OWL, have led to an increased interest in and tool development for ontologies. OWL is based, on the one hand, on web standards and, on the other hand, on Description Logics: these are decidable fragments of first order logic and close relatives of modal logics that have been developed for knowledge representation and reasoning. I will briefly introduce OWL and then describe some of the recent developments. In the last 15 years, significant progress has been made regarding so-called standard reasoning tasks through the optimisation of existing and development of new reasoning techniques, so that we can now reason over extremely large, modestly complex theories and answer queries against databases w.r.t. ontologies. This has led to "serious" engineering of ontologies, which requires ever more and powerful so-called non-standard reasoning services such as the extraction of modules, the logically sound partitioning and diffing of ontologies, the retrieval and analysis of performance hotspots, or the explanation of entailments from an ontology. In the seminar, I will give an overview of these services.