A REVISED TWO-PHASE METHOD FOR DECOMPOSITION OF DESIGN PROBLEMS

The two-phase decomposition method has two major components: dependency analysis and partitioning analysis, which offer necessary sub-functions for problem decomposition [1]. While dependency analysis focuses on analyzing the dependency structure of a given design problem, partitioning analysis utilizes the results from dependency analysis to identify design sub-problems and their interaction. In the original version of the two-phase method, only two types of coupling in a design problem are considered: coupling between any two parameters and coupling between any two functions. This methodological arrangement has overlooked the coupling between a design function and a design parameter. Thus, this paper proposes a revision of the two-phase method by considering this type of coupling. The revised two-phase method uses the approach of coupling matrix concatenation to unify different types of coupling, and it can simplify and expedite the original decomposition process. The examples of the relief valve and powertrain systems are used to demonstrate the utility of the revised method.