Dynamic updates of non-monotonic knowledge bases

Dynamic updates of non-monotonic knowledge bases

In this paper we investigate updates of knowledge bases represented by logic programs. In order to represent negative information, we use generalized logic programs which allow default negation not only in rule bodies but also in their heads. We start by introducing the notion of an update P U of one logic program P by another logic program U. Subsequently, we provide a precise semantic charact...

Verification of non-monotonic knowledge bases

Ž . Non-monotonic Knowledge-Based Systems KBSs must undergo quality assurance procedures for the following two Ž . Ž . reasons: i belief revision if such is provided cannot always guarantee the structural correctness of the knowledge base, Ž . and in certain cases may introduce new semantic errors in the revised theory; ii non-monotonic theories may have multiple extensions, and some types of f...

Irrelevant Updates of Nonmonotonic Knowledge Bases

The second postulate of Katsuno and Mendelzon, 2[KM] hereafter, characterizes irrelevant updates: if ψ implies μ, then ψ μ is equivalent to ψ, where ψ is a knowledge base, μ is an update and is an update operator [3]. We show that the postulate has to be modified, if nonmonotonic assumptions are considered. Our characterization of irrelevant updates is based on a dependency framework [5], which...

Rule Based Updates on Simple Knowledge Bases

In this paper we consider updates that are specified as rules and consider simple knowledge bases consisting of ground atoms. We present a translation of the rule based update specifications to extended logic programs using situation calculus notation so as to compute the updated knowledge base. We show that the updated knowledge base that we compute satisfies the update specifications and yet ...

Non - Monotonic Inference on Sequenced Belief Bases (