A Conjunctive Query Language for Description Logic Aboxes

Abstract

A serious shortcoming of many Description Logic based knowledge representation systems is the inadequacy of their query languages. In this paper we present a novel technique that can be used to provide an expressive query language for such systems. One of the main advantages of this approach is that, being based on a reduction to knowledge base satisfiability, it can easily be adapted to most existing (and future) Description Logic implementations. We believe that providing Description Logic systems with an expressive query language for interrogating the knowledge base will significantly increase their utility. Introduction A description logic (DL) knowledge base (KB) is made up of two parts, a terminological part (the Tbox) and an assertional part (the Abox), each part consisting of a set of axioms. The Tbox asserts facts about concepts (sets of objects) and roles (binary relations), usually in the form of inclusion axioms, while the Abox asserts facts about individuals (s...