Disjunctive Logic Programming (DLP) is an advanced formalism for Knowledge Representation and Reasoning (KRR). DLP is very expressive in a precise mathematical sense: it allows to ...
Though overriding as a single and default mode of inheritance is adequate for most knowledge bases, a large class of applications naturally requires several inheritance modes and ...
We give a polymorphic account of the relational algebra. We introduce a formalism of \type formulas" speci cally tuned for relational algebra expressions, and present an algo...