基于粗糙集理论的产品结构设计模糊评价

Fuzzy evaluation of product structural design using rough set theory

针对产品结构设计模糊评价中出现的不合理评价结果,分析了模糊变换在多指标情况下存在权重向量分量数值过小的问题。以减少参加评价指标的数量为目的,采用基于粗糙集理论的知识约简方法,分别实现了完备信息系统和不完备信息系统中产品结构设计评价指标的约简,并用约简后的评价指标再进行模糊变换。对液力变矩器结构设计合理性模糊评价的实例验证表明:先约简后评价的方法,不但可简化评价工作的运算量,避免不合理的评价结果,而且不影响评价质量。

The problem of fuzzy mapping algorithms with multiple indices having excessively small weighing vector components was anaiyzed to preciudc irrational evaluation results arising in the fuzzy evaluation of product structural designs. The analysis seeks to reduce the primary contributed evaluation index number. This paper describes a knowledge reduction method based on roughness set theory with separate implementations of the evaluation index reduction for product structural designs with perfect and imperfect information systems. The reduced evaluation index is then again processed with the fuzzy mapping. An instance validation of the structural design rationality of a hydraulic torque converter indicates that the reduction before evaluation not only simplifies the calculations, but also avoids irrational evaluation results without affecting the evaluation quality.