关于工程系统全局全寿命优化模型的讨论

Models of overall situation and whole life optimization for engineering systems

以往的优化设计理论针对的都是具体的结构,而在工程实际中,一般都是整个工程大系统的优化设计问题,其由众多子系统或者结构组成,具有高维数、多目标、变量种类多、约束耦合复杂等难点,故其子系统的独立优化并不能带来整个大系统的优化方法,如耦合法、分解协调法(模型协调法、目标协调法),都是针对特殊的数学模型而提出的,实际上工程系统的优化模型往往预先不知道,需要通过子系统或者结构的具体优化模型来构造大系统的全局优化模型,故这些方法难以应用。考虑了工程系统中的动态可靠度与模糊因素,给出了全局全寿命优化模型,构造了分解协调算法。

A new method of overall optimization design is introduced. The previous theory of optimization design usually deals with concrete structure. But what is encountered in the practical engineering is often the optimization design problems of the whole engineering system which consists of many subsystems or structures. They are difficult to handle because of their high dimension, changeable factors and constrained coupling complexity. So the individual optimization design of the subsystem can' t bring out global optimization of the whole system. Therefore, the previous theory of structure optimizatian design can't meet the need of practical engineering. In addition, the existing optimization methods on whole system such as the method coupling and the decomposition and coordination method (codel coordination and target coordination) all deal with special mathematical modes. In fact, optimization models of an engineering system can't be known beforehand and are usually formed via concrete optimization models of subsystems or structures. So it is very hard to apply these methods. By taking the dynamic reliability and fuzzy factors in engineering systems into consideration, the global and optimization model of an engineering system is put forward, and its decomposition and coordination algorithm is established.