Abstract
AbstractThis paper partially bridges a gap in the literature on Circumscription in Description Logics by investigating the tractability of conjunctive query answering in OWL2’s profiles. It turns out that the data complexity of conjunctive query answering is coNP-hard in circumscribed $\mathcal {E}{\mathscr{L}}$
E
L
and DL-lite, while in circumscribed OWL2-RL conjunctive queries retain their classical semantics. In an attempt to capture nonclassical inferences in OWL2-RL, we consider conjunctive queries with safe negation. They can detect some of the nonclassical consequences of circumscribed knowledge bases, but data complexity becomes coNP-hard. In circumscribed $\mathcal {E}{\mathscr{L}}$
E
L
, answering queries with safe negation is undecidable.
Funder
Università degli Studi di Napoli Federico II
Publisher
Springer Science and Business Media LLC
Subject
Applied Mathematics,Artificial Intelligence
Reference29 articles.
1. Ahmetaj, S., Ortiz, M., Simkus, M.: Polynomial rewritings from expressive description logics with closed predicates to variants of Datalog. Artif. Intell. 280, 103–220 (2020)
2. Alviano, M., Morak, M., Pieris, A.: Stable model semantics for tuple-generating dependencies revisited. In: Sallinger, E., den Bussche, J.V., Geerts, F. (eds.) Proceedings of the 36th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems, PODS Chicago, IL, USA, May 14-19, 2017, pp 377–388. ACM (2017)
3. Alviano, M., Pieris, A.: Default negation for non-guarded existential rules. In: Milo, T., Calvanese, D. (eds.) Proceedings of the 34th ACM Symposium on Principles of Database Systems, PODS Melbourne, Victoria, Australia, May 31 - June 4, 2015, pp 79–90 (2015)
4. Baader, F., Calvanese, D., McGuinness, D. L., Nardi, D., Patel-Schneider, P. F. (eds.): The Description Logic Handbook: Theory, Implementation, and Applications. Cambridge University Press, Cambridge (2003)
5. Baader, F., Hollunder, B.: Embedding defaults into terminological knowledge representation formalisms. J. Autom. Reasoning 14(1), 149–180 (1995)