My research interests include knowledge representation, ontologies and ontology languages, modal and description logics, automated reasoning, implementation and optimisation of reasoning systems, and applications in areas such as e-Science and the Semantic Web.
The main focus of my work is the development of (description) logic based ontology languages and “practical” reasoning systems. I was a member of the W3C WebOntology working group that developed the OWL language (now a W3C recommendation), and was jointly responsible for the development of it's predecessors OIL and DAML+OIL. More recently, I have (jointly) authored W3C member submissions describing the SWRL Semantic Web Rules Language, and the OWL 1.1 extension to OWL, the latter of which is now the basis for a new W3C OWL Working Group that I am co-chairing.
I designed and implemented the innovative and widely imitated FaCT system, the success of which was one of the motivations for basing the OWL ontology language on a description logic. FaCT has now been superseded by FaCT++, which was jointly developed with Dmitry Tsarkov. More recently, I have been involved in the design of HermiT, a new Hypertableau based reasoner being developed by Boris Motik and Rob Shearer.
