A Knowledge Compilation Technique for ALC Tboxes

Knowledge compilation is a common technique for propo-sitional logic knowledge bases. A given knowledge base is transformed into a normal form, for which queries can be an-swered efficiently. This precompilation step is expensive, but it only has to be performed once. We apply this technique to knowledge bases defined in the Description Logic ALC. We discuss an efficient satisfiability test as well as a subsumption test for precompiled concepts and Tboxes. Further we use the precompiled Tboxes for efficient Tbox reasoning. Finally we present first experimental results of our approach