{"type":"ScholarlyArticle","title":"The Combined Approach to Query Answering Beyond the OWL 2 Profiles","authors":[{"name":"Cristina Feier","slug":"cristina-feier","given":"Cristina","family":"Feier","affiliation":""},{"name":"David Carral","slug":"david-carral","given":"David","family":"Carral","affiliation":""},{"name":"Giorgio Stefanoni","slug":"giorgio-stefanoni","given":"Giorgio","family":"Stefanoni","affiliation":""},{"name":"Bernardo Cuenca Grau","slug":"bernardo-cuenca-grau","given":"Bernardo Cuenca","family":"Grau","affiliation":""},{"name":"Ian Horrocks","slug":"ian-horrocks","given":"Ian","family":"Horrocks","affiliation":""}],"abstract":"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.","doi":null,"url":"https://ijcai.org/proceedings/2015/420","pdf":"https://ijcai.org/proceedings/2015/0420.pdf","markdown":"https://ijcai.org/proceedings/2015/420.md","bibtex":"https://ijcai.org/proceedings/2015/bibtex/420","volume":{"slug":"2015","title":"Proceedings of the Twenty-Fourth International Joint Conference on Artificial Intelligence","short_title":"IJCAI 2015","url":"https://ijcai.org/proceedings/2015/","year":2015,"location":"Buenos Aires, Argentina","dates":"25–31 July 2015","editors":"Qiang Yang and Michael Wooldridge","isbn":"978-1-57735-738-4","publisher":"International Joint Conferences on Artificial Intelligence","doi_prefix":""},"section":"Special Track on Knowledge Representation and Reasoning","track":"Special Track on Knowledge Representation and Reasoning","number":420,"pages":{"first":2971,"last":2976},"keywords":[],"videos":[],"references":[],"license_note":"Copyright International Joint Conferences on Artificial Intelligence."}