抄録
There are design problems of a complex product at system requirements analysis phase on V-shape process, which it is difficult to transfer system requirements from product requirements. The cause of this problem originates in unestablished design process to decompose of requirements and behaviors of a product. In this paper we discuss three processes of the stepwise design process which consist of decomposition of requirements and behaviors using problem frame, selection of functional structures from feature model which satisfy these requirements and behaviors, and refinement of model using state transition analysis. The effects of the process is shown corresponding to those problems.
