Fuzzy nearness degree algorithm of fuzzy multiple attribute decision-making for structural scheme design

Because of the 'Soft Science' features of structural scheme design, the problem of structural scheme design should be solved by the theory of 'Soft Design' and the methodologies of 'Soft Computing'. The problem-solving process for structural scheme design includes three sub-processes, i.e., scheme generation, scheme evaluation and scheme decision-making. As to the scheme decision-making, the choice of the optimal structural scheme belongs to the scope of Multiple Attribute Decision Making. However, this type of problem cannot be effectively solved by the traditional theories of Multiple Criterion Decision Making in which the preference information of the decision-makers and the attributes of structural schemes are uncertain in nature. To overcome these difficulties, a fuzzy multiple attribute decision-making model for structural form selection is built up in this paper. A method of determining the fuzzy satisfaction degree matrix of the attributes of structural forms is put forward to effectively process the fuzzy information. To get over the shortcomings of determining the optimal preferred scheme directly through Euclid distance, a fuzzy multiple attribute decision-making method based on fuzzy nearness degree is proposed. The decision making process of selecting the optimal structural scheme is demonstrated by taking large-span spatial structures as a practical example. The results of the engineering practice show that the method proposed by this paper can effectively solve the problem of selecting the optimal structural scheme in uncertain environment.