A non-monotonic Description Logic for reasoning about typicality

作者：Giordano L; Gliozzi V; Olivetti N; Pozzato G L^*

来源：Artificial Intelligence, 2013, 195: 165-202.

DOI：10.1016/j.artint.2012.10.004

• Description Logics
• Non-monotonic reasoning
• Tableau calculi
• Prototypical reasoning

In this paper we propose a non-monotonic extension of the Description Logic ALC for reasoning about prototypical properties and inheritance with exceptions. The resulting logic, called ALC + T-min, is built upon a previously introduced (monotonic) logic ALC + T that is obtained by adding a typicality operator T to ALC. The operator T is intended to select the %26quot;most normal%26quot; or %26quot;most typical%26quot; instances of a concept, so that knowledge bases may contain subsumption relations of the form T(C) subset of D (%26quot;T(C) is subsumed by D%26quot;), expressing that typical C-members are instances of concept D. From a knowledge representation point of view, the monotonic logic ALC + T is too weak to perform inheritance reasoning. In ALC + T-min, in order to perform non-monotonic inferences, we define a %26quot;minimal model%26quot; semantics over ALC + T. The intuition is that preferred or minimal models are those that maximize typical instances of concepts. By means of ALC + T-min we are able to infer defeasible properties of (explicit or implicit) individuals. We also present a tableau calculus for deciding ALC + T-min entailment that allows to give a complexity upper bound for the logic, namely that query entailment is in co-NExp(NP).

• 出版日期2013-2