TY - CONF T1 - The Combined Approach to Query Answering Beyond the OWL 2 Profiles T2 - Proceedings of the 24th International Joint Conference on Artificial Intelligence (IJCAI) Y1 - 2015 A1 - Cristina Feier A1 - David Carral A1 - Giorgio Stefanoni A1 - Cuenca Grau, Bernardo A1 - Ian Horrocks AB -

Combined approaches have become a successful technique for CQ answering over ontologies. Existing algorithms, however, are restricted to the logics underpinning the OWL 2 profiles. Our goal is to make combined approaches applicable to a wider range of ontologies. We focus on RSA: a class of Horn ontologies that extends the profiles while ensuring tractability of standard reasoning. We show that CQ answering over RSA ontologies without role composition is feasible in NP. Our reasoning procedure generalises the combined approach for ELHO and DL-LiteR using an encoding of CQ answering into fact entailment w.r.t. a logic program with function symbols and stratified negation. Our results have significant practical implications since many out-of-profile Horn ontologies are RSA.

JF - Proceedings of the 24th International Joint Conference on Artificial Intelligence (IJCAI) UR - http://www.cs.ox.ac.uk/isg/people/cristina.feier/ijcai_rsafinal.pdf ER - TY - CONF T1 - Extending the Combined Approach Beyond Lightweight Description Logics T2 - Proceedings of the 28th International Workshop on Description Logics (DL) Y1 - 2015 A1 - Cristina Feier A1 - David Carral A1 - Giorgio Stefanoni A1 - Cuenca Grau, Bernardo A1 - Ian Horrocks AB -

Combined approaches have become a successful technique for CQ answering over ontologies. Existing algorithms, however, are restricted to the logics underpinning the OWL 2 profiles. Our goal is to make combined approaches applicable to a wider range of ontologies. We focus on RSA: a class of Horn ontologies that extends the profiles while ensuring tractability of standard reasoning. We show that CQ answering over RSA ontologies without role composition is feasible in NP. Our reasoning procedure generalises the combined approach for ELHO and DL-LiteR using an encoding of CQ answering into fact entailment w.r.t. a logic program with function symbols and stratified negation. Our results are significant in practice since many out-of-profile Horn ontologies are RSA.

JF - Proceedings of the 28th International Workshop on Description Logics (DL) UR - http://www.cs.ox.ac.uk/isg/people/cristina.feier/pdfs/dlmain.pdf ER -