Current research in knowledge representation
An issue now preoccupying much research effort is how to define the precise dimensions and formal underpinnings of knowledge representation. Many researchers have attempted to outline the basic dimensions of the knowledge-representation problem. The attempt to provide precise semantics to knowledge representation formalisms is proceeding on several fronts. Thus, work on nonmonotonic logic tries to extend predicate calculus to handle a wider variety of phenomena while maintaining its formal semantics, while some research on semantic networks attempts to formalize semantic network while maintaining their elegant structuring and inferencing capabilities. Knowledge-representation languages (e.g., KRL, Microplanner) try to define what various knowledge-representation constructs mean through the precision of an interpreter. (Most of these languages promote the representation of knowledge in networks of framelike objects, and several are now actually used in AI labs. )