船舶系统可靠性指标分配的多目标优化方法

Study of multi-objective optimization and multi-attribute decision making of reliability for ship complex system

针对船舶系统可靠性设计问题,采用改进非支配排序遗传算法(NSGAII)研究了可靠性指标分配中的多目标优化设计。根据Pareto最优解集形成决策矩阵,基于信息熵法得到属性权重,利用逼近理想解的排序方法(TOPSIS)进行多属性决策研究,对Pareto最优解给出排序。采用本文方法讨论了一个船舶系统可靠度的分配和预测算例,给出了可靠度和费用之间的拟合关系。数值算例表明,综合采用多目标优化和多属性决策技术,可以迅速、客观选择各部件的可靠度。这种综合方法还能用于可靠性研究的其他领域。

Multi-objective optimization and multi-attribute decision making study of reliability allocation is evaluated in present study. A hybrid approach is proposed for reliability optimization. In the first stage,a Non-dominated Sorting Genetic Algorithm Ⅱ（NSGA Ⅱ）is employed to approximate the set of Pareto solution through an evolutionary optimization process. In the subsequent stage, a multi-attribute decision making（MADM） approach is adopted to rank these solutions from best to worst and to determine the best solution in a deterministic environment with a single decision maker. A reliability example in ship design is conducted to illustrate the analysis in present analysis. Pareto frontiers are obtained and the ranking of Pareto solution is based on entropy weight and TOPSIS method. A approximate formulation is presented for cost and reliability. The approach can be used in other reliability analysis research.