Beyond REF-ARF: Toward an Intelligent Processor for a Nondeterministic Programming Language

This document reports work on two heuristic problem solving systems, Ref2 and POPS. Both systems accept problems stated as programs in a nondeterministic programming language, and solve the problems by applying heuristic methods to find successful executions of the programs. Ref2 is patterned after Richard Fikes's system, REF-ARF, as well as additional methods based on a alternative representation for the problem context. Ref2 is also able to solve a cless of integer programming problems. POPS is a revised and extended version of Ref2, obtained by the addition of goal direction methods based on concepts from CPS.