Prioritized constraint network representation and processing for concurrent engineering models

Constraint networks are a major approach to knowledge representation in Concurrent Engineering (CE) systems. The networks model various factors in CE as constraints linked by shared variables. Many systems have been developed to assist constraint network processing. While these systems can be useful, the assumption that a solution must simultaneously satisfy all the constraints is often unrealistic and hard to achieve. Proposed in this paper is a Prioritized Constraint Network. A mechanism to propagate priorities is developed, and a new satisfrability definition taking into account the priorities is described. Strength of constraint supporters can be derived from propagated priorities. Several properties useful for investigating PCNʹs and finding effective solving strategies are developed.