Experience with approximate reliability-based optimization methods II: an exhaust system problem

Traditional reliability-based design optimization (RBDO) requires a double-loop iteration process. The inner optimization loop is to find the reliability and the outer is the regular optimization loop to optimize the RBDO problem with reliability objectives or constraints. It is known that the computation can be prohibitive when the associated function evaluation is expensive. This situation is even worse when a large number of reliability constraints are present. As a result, many approximate RBDO methods, which convert the double loop to a single loop, have been developed. In this research, an engineering problem with a large number of constraints (144) is designed to test RBDO methods based on the first-order reliability method (FORM), including single- and double-loop methods. In addition to the number of constraints, this problem possesses many local minimums. Some original authors of the RBDO methods are also asked to solve the same problem. The results and the efficiencies for different methods are published and discussed.     

特许经营权竞标与管制在电力规制应用中的对比分析

介绍了电力市场常用的两种管制手段即美国的投资回报率规制法和英国的价格上限规制法,以及新兴的特许经营权竞标措施。就管制和特许经营权竞标的特征和优劣势进行了详细的对比分析。对于管制和特许经营权竞标在电力规制中的实际应用,给出应用领域及操作方法上的建议,以期为我国电力监管提供理论及方法上的指导。     

可靠性优化方法在飞航导弹多学科设计优化中的应用

飞航导弹多学科设计优化(MDO)中,设计变量的不确定性可能降低设计结果的可靠性,传统的MDO方法无法解决这个问题。基于序贯优化和可靠性估计(SORA)的可靠性优化方法将优化设计和可靠性分析有机结合,在优化过程中考虑设计变量的不确定性,并采用单循环形式搜索优化设计结果。通过飞航导弹多学科设计优化的算例,可知基于SORA的可靠性优化方法不仅可以减小设计变量不确定性对设计结果的影响,提高可靠性,还可以有效提高计算效率。