Combining Closed World Assumptions with Stable Negation

This paper is dedicated to the memory of Cecylia Rauszer, who was both an outstanding scientist and a warm, caring and considerate person.
Department of Computer Science
Institute for Advanced Computer Studies
University of Maryland, College Park, MD 20742, USA.
Carolina Ruiz
Jack Minker

The complete paper is available in:

Abstract

We study the semantics of disjunctive logic programs that simultaneously contain multiple kinds of default negations. We introduce operators not_G, not_W, and not_STB in the language of logic programs to represent the Generalized Closed World Assumption, the Weak Generalized Closed World Assumption, and the stable negation, respectively. The notion of stratification involving different kinds of negations is defined and the meaning of stratified programs with multiple negations is described. The class of stratified programs is extended to the class of quasi-stratified programs and the semantics of the latest class is studied.