Study On Optimum Decision-making For Boarding Bridge Structures Based On Fuzzy Theory And Neural Network And Its Application

Multiobjective multilayer comprehensive evaluation problem of complex object systems has been studied and concerned widely in the fields of engineering. The comprehensive evaluation of boarding bridge structures is typical multiobjective multilayer comprehensive evaluation problem, it involves a lot of complicated influence factors which are described in different way, and there are many fuzzy phenomena in it, therefore, it is essential to seek a scientific and reasonable comprehensive evaluation method.Fuzzy comprehensive evaluating method (abbreviated as FCEM) based on fuzzy theory is an evaluation method used for the object system involved fuzzy factors.FCEM can solute fuzzy problem effectively in the evaluation. Artificial Neural Network (abbreviated as ANN) has very strong robustness, fault-tolerance, learning ability and adaptability, and shows to superiority in setting up model for complicated system, so ANN is suited for the evaluation of complicated object projects.After thoroughly analyzing the characteristics of comprehensive evaluation of complex object systems and the evaluation study actuality ,this paper studies the solution to the comprehensive evaluation of boarding bridge structures using FCEM and ANN based on the fuzzy theory and ANN theory. The main studying contents of this paper are as follows: (1) It establishes the model of FCEM on the base of fuzzy theory, and makes a discussion on some critical problems of the creation of FCEM model;(2) It makes the comprehensive evaluation of boarding bridge structures based on the three-stage FCEM model. It establishes part of evaluation factor aggregation using the finite element method by ANSYS ,and defines the weight coefficient by the improved AHP ,and studies the constructing policy of member ship function, and defines the subject degree vector of qualitative factors and quantitative factors;(3) It puts forward the evaluation model and arithmetic of the solution process on the base of ANN theory, and founds evaluation model based on BP network and Radial Basis Function network respectively with MATLAB toolbox;(4) It puts forward a design idea that use the FCEM and ANNto make the comprehensive evaluation of boarding bridge structures synthetically, and studies the way of series-combining of two methods, and establishes evaluation model based on fuzzy theory and ANN, finally uses this model realizes the comprehensive evaluation of boarding bridge structures ,the evaluation result shows that this model is available and reasonable; (5) It designs a intellectualized comprehensive evaluation software system based on fuzzy theory and ANN with the help of Visual Basic , data-base technique and MATLAB toolbox, and studies the method of the programming interface between Visual Basic and MATLAB, and puts it into practice, finally verifies the dependability of this evaluation software by actual application.The comprehensive evaluation method established by this paper will provide dependable and useful reference to the design and optimum decision-makings for boarding bridge structures.