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arXiv · 0711.2155

Guarded Hybrid Knowledge Bases

Stijn Heymans·Jos de Bruijn·Livia Predoiu·Cristina Feier·Davy Van Nieuwenborgh
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Abstract

Recently, there has been a lot of interest in the integration of Description Logics and rules on the Semantic Web.We define guarded hybrid knowledge bases (or g-hybrid knowledge bases) as knowledge bases that consist of a Description Logic knowledge base and a guarded logic program, similar to the DL+log knowledge bases from (Rosati 2006). G-hybrid knowledge bases enable an integration of Description Logics and Logic Programming where, unlike in other approaches, variables in the rules of a guarded program do not need to appear in positive non-DL atoms of the body, i.e. DL atoms can act as guards as well. Decidability of satisfiability checking of g-hybrid knowledge bases is shown for the particular DL DLRO, which is close to OWL DL, by a reduction to guarded programs under the open answer set semantics. Moreover, we show 2-EXPTIME-completeness for satisfiability checking of such g-hybrid knowledge bases. Finally, we discuss advantages and disadvantages of our approach compared with DL+log knowledge bases.

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Stijn Heymans, Jos de Bruijn, Livia Predoiu, Cristina Feier, Davy Van Nieuwenborgh. 2007-11-14. Guarded Hybrid Knowledge Bases. https://arxiv.org/abs/0711.2155

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