For the problem of missile condition evaluation and decision,a method of missile condition evaluation and decision based on improved grey relational analysis with combination weighting is proposed.By analyzing the influencing factors of missile state,the index system of missile state parameters is constructed.On this basis,the improved grey relational analysis method is used to evaluate the missile state and make decision.Because the grey correlation analysis can only give the order of the correlation coefficient of the missile state to be selected,it can not reflect the real state of the missile.It is improved by introducing the lowest state parameter comparison sequence to obtain the objective missile state.The determination of gray relational analysis index weights is a key factor in determining the accuracy of the evaluation.In order to balance the advantages and disadvantages of subjective weighting and objective weighting,the weight determination scheme of the combination of Fuzzy AHP and entropy weight method is used.Through the analysis of an example and comparison with traditional methods,the feasibility and accuracy of the method are verified.

Aiming at the conflict and uncertainty of the test data required in the quality assessment, and the incompleteness and inaccuracy of the condition assessment, an improved method of evidential reasoning (ER) is proposed. After the quality grading and test data pretreatment, the conflict between the information and the overall uncertainty are assigned to each level of probability to reduce conflict and overall uncertainty between the evidence assessed. The method is applied to the missile equipment quality condition assessment, and the results and algorithm comparison show that the improved evidence reasoning method can effectively reduce the conflict of evidence, and the overall uncertainty of condition assessment is greatly reduced. The principle of the method is simple, the theoretical basis is sufficient, and the program is convenient to be realized.

The economic and efficient level of repair is needed for the invalid parts in reality, which is often affected by many factors. Combined with the existing results, the decision-making flow chart is utilized for multi-level maintenance process of a certain equipment from the perspective of qualitative and quantitative. A multi-objective optimization model including economic and non-economic indicators is built. The optimal solution is determined by the combination of TOPSIS (technique for order preference by similarity to an ideal solution) and genetic algorithm which is illustrated effectively, and provides a reference for maintenance support of equipment.