Approximate Well-Founded Semantics, Query Answering and Generalized Normal Logic Programs over Lattices

In Annals of Mathematics and Artificial Intelligence, 2009.

The management of imprecise information in logic programs becomes important whenever the real world information to be represented is of an imperfect nature and the classical crisp "true, false" approximation is not adequate. In this work, we consider normal logic programs over complete lattices, where computable truth combination functions may appear in the rule bodies to manipulate truth values and we will provide a top-down query answering procedure.