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Abstract

Unification in Description Logics has been proposed as a novel inference service that can, for example, be used to detect redundancies in ontologies. In a recent paper, we have shown that unification in \(\mathcal{EL}\) is NP-complete, and thus of a complexity that is considerably lower than in other Description Logics of comparably restricted expressive power. In this paper, we introduce a new NP-algorithm for solving unification problems in \(\mathcal{EL}\), which is based on a reduction to satisfiability in propositional logic (SAT). The advantage of this new algorithm is, on the one hand, that it allows us to employ highly optimized state-of-the-art SAT solvers when implementing an \(\mathcal{EL}\)-unification algorithm. On the other hand, this reduction provides us with a proof of the fact that \(\mathcal{EL}\)-unification is in NP that is much simpler than the one given in our previous paper on \(\mathcal{EL}\)-unification.

Keywords

Description Logic Propositional Variable Horn Clause Concept Variable Concept Term 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Franz Baader
    • 1
  • Barbara Morawska
    • 1
  1. 1.Theoretical Computer ScienceTU DresdenGermany

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