Partial Models of Extended Generalized Logic Programs

In recent years there has been an increasing interest in extensions of the logic programming paradigm beyond the class of normal logic programs motivated by the need for a satisfactory respresentation and processing of knowledge. An important problem in this area is to find an adequate declarative semantics for logic programs. In the present paper a general preference criterion is proposed that selects the ‘intended’ partial models of extended generalized logic programs which is a conservative extension of the stationary semantics for normal logic programs of [13], [14] and generalizes the WFSX-semantics of [12]. The presented preference criterion defines a partial model of an extended generalized logic program as intended if it is generated by a stationary chain. The GWFSX-semantics is defined by the set-theoretical intersection of all stationary generated models, and thus generalizes the results from [9] and [1].