应用贝叶斯方法进行系统可靠性验证

可靠性验证是系统开发过程中的重要环节.在实际工程应用中,由于复杂系统在开发过程中样本数量极少,使得按传统方法进行系统的可靠性验证十分困难.本文基于贝叶斯方法和系统研制过程中可靠性信息的利用,提出了复杂系统可靠性综合验证方法.该方法将部件的设计分析作为部件可靠性的验前信息,并用部件寿命试验结果将其更新;根据系统结构,将各部件更新后的可靠性信息综合,得出系统验前可靠性信息;以该信息为基础,制定和实施系统可靠性验证试验计划.该法的应用表明,对于复杂系统在研制阶段进行可靠性验证,所需样本数明显少于基于经典可靠性理论所需的样本数.

A SYSTEM RELIABILITY DEMONSTRATION METHOD BASED ON BAYES THEOREM

A final system reliability demonstration testing is needed before the system is released for production. According to classical reliability, a large sample size is required to demonstrate system reliability as the demonstration does not make use of all information in the system development process. The paper presented a Bayesian framework of integrated reliability demonstration in system development. The proposed framework relies on component design analysis as the prior reliability knowledge of the components. Results of life test of the components are used to update the reliability of components. The updated reliability of components is then integrated to form the prior reliability knowledge of the system according to system structure. Based on the prior reliability of the system, a reliability demonstration test plan of the system was developed. An example illustrates this process and application issues are addressed. With this framework, the importance of upfront design and development on system reliability is clarified, and the sample size required to demonstrate system reliability can be much reduced compared with that required by classical reliability theory.