WORL: a nonmonotonic rule language for the semantic web
Son Thanh Cao, Linh Anh Nguyen, Andrzej Szałas · Vietnam Journal of Computer Science · 2013
We develop a new Web ontology rule language, called WORL, which combines a variant of OWL 2 RL with eDatalog $$^\lnot $$ . We allow additional features like negation, the minimal number restriction and unary external checkable predicates to occur at the left-hand side of concept inclusion axioms. Some restrictions are adopted to guarantee a translation into eDatalog $$^\lnot $$ . We also develop the well-founded semantics and the stable model semantics for WORL as well as the standard semantics for stratified WORL (SWORL) via translation into eDatalog $$^\lnot $$ . Both WORL with respect to the well-founded semantics and SWORL with respect to the standard semantics have PTime data complexity. In contrast to the existing combined formalisms, in WORL and SWORL negation in concept inclusion axioms is interpreted using nonmonotonic semantics.