Conjunctive query answering over unrestricted OWL 2 ontologies

被引:1
作者
Igne, Federico [1 ]
Germano, Stefano [1 ]
Horrocks, Ian [1 ]
机构
[1] Univ Oxford, Dept Comp Sci, Parks Rd, Oxford OX1 3QD, England
基金
英国工程与自然科学研究理事会;
关键词
CQ answering; OWL; 2; ontology approximation; RSA; combined approach; KNOWLEDGE REPRESENTATION; SYSTEM; MATERIALIZATION;
D O I
10.3233/SW-233382
中图分类号
TP18 [人工智能理论];
学科分类号
081104 ; 0812 ; 0835 ; 1405 ;
摘要
Conjunctive Query (CQ) answering is a primary reasoning task over knowledge bases. However, when considering expressive description logics, query answering can be computationally very expensive; reasoners for CQ answering, although heavily optimized, often sacrifice expressive power of the input ontology or completeness of the computed answers in order to achieve tractability and scalability for the problem. In this work, we present a hybrid query answering architecture that combines various services to provide a CQ answering service for OWL. Specifically, it combines scalable CQ answering services for tractable languages with a CQ answering service for a more expressive language approaching the full OWL 2. If the query can be fully answered by one of the tractable services, then that service is used, to ensure maximum performance. Otherwise, the tractable services are used to compute lower and upper bound approximations. The union of the lower bounds and the intersection of the upper bounds are then compared. If the bounds do not coincide, then the "gap" answers are checked using the "full" service. These techniques led to the development of two new systems: (i) RSAComb, an efficient implementation of a new tractable answering service for RSA (role safety acyclic) (ii) ACQuA, a reference implementation of the proposed hybrid architecture combining RSAComb, PAGOdA, and HermiT to provide a CQ answering service for OWL. Our extensive evaluation shows how the additional computational cost introduced by reasoning over a more expressive language like RSA can still provide a significant improvement compared to relying on a fully-fledged reasoner. Additionally, we show how ACQuA can reliably match the performance of PAGOdA, a state-of-the-art CQ answering system that uses a similar approach, and can significantly improve performance when PAGOdA extensively relies on the underlying fully-fledged reasoner.
引用
收藏
页码:997 / 1050
页数:54
相关论文
共 84 条
[21]  
Eiter Thomas, 2012, P 26 AAAI C ARTIFICI
[22]  
Erling O, 2010, SEMANTIC WEB INFORMATION MANAGEMENT, P501, DOI 10.1007/978-3-642-04329-1_21
[23]  
Feier C, 2015, PROCEEDINGS OF THE TWENTY-FOURTH INTERNATIONAL JOINT CONFERENCE ON ARTIFICIAL INTELLIGENCE (IJCAI), P2971
[24]  
Gangemi A, 2002, LECT NOTES ARTIF INT, V2473, P166
[25]  
Glimm B., 2014, CEUR Workshop Proceedings, V1265, P1
[26]  
Glimm B., 2007, CEUR Workshop Proceedings, V250
[27]   Conjunctive query answering for the description logic SHIQ [J].
Glimm, Birte ;
Horrocks, Ian ;
Luts, Carsten ;
Sattler, Ulrike .
JOURNAL OF ARTIFICIAL INTELLIGENCE RESEARCH, 2008, 31 :157-204
[28]  
Glimm B, 2015, AAAI CONF ARTIF INTE, P109
[29]   HermiT: An OWL 2 Reasoner [J].
Glimm, Birte ;
Horrocks, Ian ;
Motik, Boris ;
Stoilos, Giorgos ;
Wang, Zhe .
JOURNAL OF AUTOMATED REASONING, 2014, 53 (03) :245-269
[30]  
Grosof BenjaminN., 2003, P 12 INT WORLD WIDE, P48, DOI DOI 10.1145/775152.775160