确信可靠性理论是近些年来提出的一种全新的可靠性理论。在确信可靠性理论中,性能裕量是开展可靠性度量与分析的核心概念。如何在产品设计过程中对关键性能参数进行辨识和对性能裕量进行分析,是首先要解决的重要问题。为此,提出一种新...确信可靠性理论是近些年来提出的一种全新的可靠性理论。在确信可靠性理论中,性能裕量是开展可靠性度量与分析的核心概念。如何在产品设计过程中对关键性能参数进行辨识和对性能裕量进行分析,是首先要解决的重要问题。为此,提出一种新型形式化分析方法——功能、性能与裕量分析(function,performance and margin analysis,FPMA),以有序地梳理产品功能、性能关系,辨识关键性能参数及性能阈值,从而为后续的裕量建模与可靠性分析奠定信息和认知基础。详细阐述了该方法的内涵与基本流程,明确了其在产品全寿命周期内的应用价值,并以某型电连接器为例开展了案例研究。结果表明,开展FPMA能够全面挖掘产品可靠性相关信息,有利于真正把可靠性融入产品的设计中。展开更多
In equipment integrated logistics support(ILS), the supply capability of spare parts is a significant factor. There are lots of depots in the traditional support system, which makes too many redundant spare parts and ...In equipment integrated logistics support(ILS), the supply capability of spare parts is a significant factor. There are lots of depots in the traditional support system, which makes too many redundant spare parts and causes high cost of support. Meanwhile,the inconsistency among depots makes it difficult to manage spare parts. With the development of information technology and transportation, the supply network has become more efficient. In order to further improve the efficiency of supply-support work and the availability of the equipment system, building a system of one centralized depot with multiple depots becomes an appropriate way.In this case, location selection of the depots including centralized depots and multiple depots becomes a top priority in the support system. This paper will focus on the location selection problem of centralized depots considering ILS factors. Unlike the common location selection problem, depots in ILS require a higher service level. Therefore, it becomes desperately necessary to take the high requirement of the mission into account while determining location of depots. Based on this, we raise an optimal depot location model. First, the expected transportation cost is calculated.Next, factors in ILS such as response time, availability and fill rate are analyzed for evaluating positions of open depots. Then, an optimization model of depot location is developed with the minimum expected cost of transportation as objective and ILS factors as constraints. Finally, a numerical case is studied to prove the validity of the model by using the genetic algorithm. Results show that depot location obtained by this model can guarantee the effectiveness and capability of ILS well.展开更多
In reliability engineering,the observations of the variables of interest are always limited due to cost or schedule constraints.Consequently,the epistemic uncertainty,which derives from lack of knowledge and informati...In reliability engineering,the observations of the variables of interest are always limited due to cost or schedule constraints.Consequently,the epistemic uncertainty,which derives from lack of knowledge and information,plays a vital influence on the reliability evaluation.Belief reliability is a new reliability metric that takes the impact of epistemic uncertainty into consideration and belief reliability distribution is fundamental to belief reliability application.This paper develops a new method called graduation formula to construct belief reliability distribution with limited observations.The developed method constructs the belief reliability distribution by determining the corresponding belief degrees of the observations.An algorithm is designed for the graduation formula as it is a set of transcendental equations,which is difficult to determine the analytical solution.The developed method and the proposed algorithm are illustrated by two numerical examples to show their efficiency and future application.展开更多
文摘确信可靠性理论是近些年来提出的一种全新的可靠性理论。在确信可靠性理论中,性能裕量是开展可靠性度量与分析的核心概念。如何在产品设计过程中对关键性能参数进行辨识和对性能裕量进行分析,是首先要解决的重要问题。为此,提出一种新型形式化分析方法——功能、性能与裕量分析(function,performance and margin analysis,FPMA),以有序地梳理产品功能、性能关系,辨识关键性能参数及性能阈值,从而为后续的裕量建模与可靠性分析奠定信息和认知基础。详细阐述了该方法的内涵与基本流程,明确了其在产品全寿命周期内的应用价值,并以某型电连接器为例开展了案例研究。结果表明,开展FPMA能够全面挖掘产品可靠性相关信息,有利于真正把可靠性融入产品的设计中。
基金supported by the Science Challenge Project(TZ2018007)the National Natural Science Foundation of China(71671009+2 种基金 61871013 61573041 61573043)
文摘In equipment integrated logistics support(ILS), the supply capability of spare parts is a significant factor. There are lots of depots in the traditional support system, which makes too many redundant spare parts and causes high cost of support. Meanwhile,the inconsistency among depots makes it difficult to manage spare parts. With the development of information technology and transportation, the supply network has become more efficient. In order to further improve the efficiency of supply-support work and the availability of the equipment system, building a system of one centralized depot with multiple depots becomes an appropriate way.In this case, location selection of the depots including centralized depots and multiple depots becomes a top priority in the support system. This paper will focus on the location selection problem of centralized depots considering ILS factors. Unlike the common location selection problem, depots in ILS require a higher service level. Therefore, it becomes desperately necessary to take the high requirement of the mission into account while determining location of depots. Based on this, we raise an optimal depot location model. First, the expected transportation cost is calculated.Next, factors in ILS such as response time, availability and fill rate are analyzed for evaluating positions of open depots. Then, an optimization model of depot location is developed with the minimum expected cost of transportation as objective and ILS factors as constraints. Finally, a numerical case is studied to prove the validity of the model by using the genetic algorithm. Results show that depot location obtained by this model can guarantee the effectiveness and capability of ILS well.
基金the National Natural Science Foundation of China(6157304371671009).
文摘In reliability engineering,the observations of the variables of interest are always limited due to cost or schedule constraints.Consequently,the epistemic uncertainty,which derives from lack of knowledge and information,plays a vital influence on the reliability evaluation.Belief reliability is a new reliability metric that takes the impact of epistemic uncertainty into consideration and belief reliability distribution is fundamental to belief reliability application.This paper develops a new method called graduation formula to construct belief reliability distribution with limited observations.The developed method constructs the belief reliability distribution by determining the corresponding belief degrees of the observations.An algorithm is designed for the graduation formula as it is a set of transcendental equations,which is difficult to determine the analytical solution.The developed method and the proposed algorithm are illustrated by two numerical examples to show their efficiency and future application.