Józef Winkowski

TOWARDS A SOLUTION TO A PLAN-FORMATION PROBLEM

948

Abstract

The paper deals with the problem of achieving a goal in a system in which certain actions can be executed. The initial state and the states that may be reached from this state by executing actions are represented by sets of sente nces, each sentence saying that some objects are or are not in a relation. Available actions are represented as instances of rewriting rules. The problem consists in finding a sequence of actions that leads from the initia l state to a state in which the goal is achieved. The presented solution to this problem for a class of systems is based on reducing it to the problem of reachability in contextual Petri nets.

Keywords : system, state, action, goal, literal, situation, rewriting rule, relational rewriting system, safe rewriting system, contextual net, safe contextual net, net morphism, contextual occurrence net, process, reachability.