Abstract
A rheological analysis system of molds was developed with the purpose of improving the yield of molded plastic semiconductor packages and shortening the time required for mold design. The capability for formulation of analytical models, which constitutes the salient feature of this system, will be described in the present paper. This system does not directly model the entire object of analysis, but rather models portions of this object and then integrates these into an overall analytical model. Approximate modelling is effected in such a manner that preprepared standard programs can be used in the respective partial models. The process of synthesizing the analytical model is represented by a hierachical structure of frames, and modelling is accomplished via the three stages of shape partitioning, shape allocation and model decision.