Uncertainty Mine With The Problem Of Optimization Methods Research

This dissertation investigates the optimization model and the algorithms in the mixture problem of raw materials in metallurgy engineering.In the metallurgy industry,the optimization of burden design is helpful to improve the qualities of products,reducing the cost and the consumption of raw material.The constraints of physical property and chemical ingredient are considered to build a mathmatical model with fuzzy parameters.Firstly,for the polymirphic uncertainty of the data from the many practical processes,we proposed a new class of prediction method.To describe this polymirphic uncertainty of the data,a kind of piecewise inference algorithm was designed to obtain the distribution function of the uncertainty variable.Under the assumption that the uncertainty variable is fuzzy stochastic,the expression of the distribution function was infered from the samples.Based on this prediction method,the alkali components in the sintering process of aluminium were predicted.It shows that the developed method is promising.Secondly,considering that the polymirphic uncertainty in the practical process,we described the mixture problem by introducing random fuzzy number,and bulit the corrsponding optimization model.By expectation method,we transformed the random fuzzy programming into a triangular fuzzy programming,and based on the ranking method of sorting function in linear programming,the original random fuzzy programming problems were transformed into the ordinary linear programming.Application of the model and the solution techniques into the mixing design in the production process of the aluminium with sintering shows that they are promising.Thirdly,for the uncertainty of ingredient in the process of mixture design,L-R fuzzy numbers are introduced to describe them,and a optimization model of mixture design is constructed.Based on the properties of theα-cuting set of fuzzy number and the membership functions,the original fuzzy program is converted to semi-infinite programming problem.By maximizing the constraint functions,the semi-infinite program is transformed into standard linear programming problem.Application of the model and the solution techniques into the mixing design in the production process of the aluminium with sintering shows that they are promising.