Artale, A. and Calvanese, D. and Kontchakov, Roman and Zakharyaschev, Michael (2009) Adding weight to DL-Lite. In: Cuenca Grau, B. and Horrocks, I. and Motik, B. and Sattler, U. (eds.) Proceedings of the 22nd International Workshop on Description Logics (DL 2009), Oxford, UK, July 27-30, 2009. CEUR Workshop Proceedings 477. CEUR Workshop Proceedings.Full text not available from this repository.
In this paper we extend the logic DL-LiteNbool and its fragments with (i) role inclusions, (ii) qualified number restrictions and (iii) role disjointness, symmetry, asymmetry, reflexivity and irreflexivity constraints. We show that if the interaction of (qualified) number restrictions with role inclusions is restricted in a way similar to DL-LiteA then the resulting logics enjoy the same computational properties as the respective fragments of DL-LiteNbool: for combined complexity, satisfiability in the full language is NP-complete and it is tractable in the Horn fragment; for data complexity, answering positive existential queries over the Horn fragment is in AC0 (and thus, FO rewritable). Our main tool for dealing with DL-Lite logics is embedding into the one-variable fragment of first-order logic without equality and function symbols, which seems to be a natural logic-based characterization of the DL-Lite logics. This embedding provides us with upper combined complexity bounds for all fragments. We also use it to obtains explicit FO rewritings of positive existential queries for the Horn fragment.
|Item Type:||Book Section|
|Additional Information:||Series ISSN: 1613-0073|
|School or Research Centre:||Birkbeck Schools and Research Centres > School of Business, Economics & Informatics > Computer Science and Information Systems|
|Date Deposited:||14 Sep 2010 13:59|
|Last Modified:||13 May 2013 12:34|
Archive Staff Only (login required)