Non-standard reasoning in Description Logics (DLs) comprises computing a Least Common Subsumer (LCS), a Concept Difference, a Concept Unifier, or an Interpolant Concept, to name a few. Although some reasoning services have been unified already (e.g., LCS and Most Specific Concept), the definition of non-standard problems and the computation that solve them are very different from each other. We propose to unify the definitions of non-standard services as special Second-order sentences in DLs; when the solution concepts are optimal with respect to some preferences, a fixpoint replaces the Second-order quantification. Moreover, we propose to combine the well-known Tableaux calculi for DLs with rules that compute substitutions of Concept Variables. We prove soundness and completeness of the combined calculus and we give a sufficient condition for termination, which covers some non-trivial cases. © 2010 The authors and IOS Press. All rights reserved.
A unified framework for non-standard reasoning services in description logics
Di Noia T.;Di Sciascio E.;Ragone Azzurra
2010-01-01
Abstract
Non-standard reasoning in Description Logics (DLs) comprises computing a Least Common Subsumer (LCS), a Concept Difference, a Concept Unifier, or an Interpolant Concept, to name a few. Although some reasoning services have been unified already (e.g., LCS and Most Specific Concept), the definition of non-standard problems and the computation that solve them are very different from each other. We propose to unify the definitions of non-standard services as special Second-order sentences in DLs; when the solution concepts are optimal with respect to some preferences, a fixpoint replaces the Second-order quantification. Moreover, we propose to combine the well-known Tableaux calculi for DLs with rules that compute substitutions of Concept Variables. We prove soundness and completeness of the combined calculus and we give a sufficient condition for termination, which covers some non-trivial cases. © 2010 The authors and IOS Press. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.