Modified Robust and Optimal Fuzzy Structural Design with Intermediate Variables

• Main Authors: Che Yu Chen, 陳則宇
• Other Authors: C.J.Shih
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/20764379778645965689

碩士 === 淡江大學 === 機械與機電工程學系 === 91 === A system of modeling and study of engineering fuzzy optimization problem with fuzzy numbers existing in allowable limit and parameters in fuzzy constraints parameters in objective functions, has been presented in this thesis. Particularly, the design problems contain fuzzy numbers existing as design variables that is practically solved by a transformation function of intermediate variable. Originally, the level-cut method has been accepted extensively as the formal way to deal with the general fuzzy constraints problems. However, when the constraints contain fuzzy parameters or fuzzy variables, the general-level cut method is not sufficiently applicable any more. In this thesis, a feasible robust approach has been developed in which a new membership function has been built depending on the fire fuzzy situations. The theory of algorithm and the illustrative design example show the better results can be obtained by applying the feasible robust membership function of fuzzy constraints. Eventually, the combined approach of intermediate variables and robust constrained membership function are presented and shows the validity as a workable and practical approach. The method presented in the thesis can reach both constraints and objective functions are robust so that the method is a robust fuzzy optimization. A simple structural design problem has been used through out the whole thesis to illustrate the presenting method. A mush complicated design problem is expected in the future for further verify the applicability to the real-world large scale design problems.