Using Preference Order in Ontologies

The latest ontology languages can be translated into a description logic (DL), thus providing them with a formal semantics and associated reasoning procedures. We introduce the ordered description logic ¢¤£¦¥§¢©¨ as a simple decidable extension of £¥§¢¨§ that supports the direct definition of a preference order on defeasible axioms, thus allowing for a succinct and intuitive expression of defeasible ontologies, containing e.g. exceptions for certain axioms. We demonstrate the usefulness of ¢¤£¦¥§¢©¨ for solving inconsistencies that may appear e.g. when merging existing ontologies. We present an algorithm that, based on concrete examples of facts that should be true, produces minimal preference orderings on the axioms, in order to make an otherwise inconsistent knowledge base consistent.

• Type: Conference
• Year: 2002
• Where: DEXAW
• Authors: Stijn Heymans, Dirk Vermeir
• Keywords: Database, Defeasible Axioms, Description Logic, DEXAW 2002, Simple Decidable Extension