Practical Applications of Bayesian Reliability

7System Reliability Bayesian Model

This chapter introduces the basics of the use of Bayesian models for assessing system reliability. There are various methods to assess system reliability or failure rate. The focus of this chapter is to discusses Bayesian methods for system reliability estimation using reliability block diagrams, fault trees, and Bayesian networks.

7.1 Introduction

System reliability is the probability of the system operating without failures for a specified period under specified use conditions. Instead of obtaining data at the system level, which can be expensive or impractical during the development phase, reliability at the component or subsystem levels is often assessed individually. System level reliability is then estimated by aggregating reliability from component level data with the overall uncertainty quantified.

Commonly used methods for system reliability estimation include reliability block diagrams, fault trees, and Bayesian networks. In this chapter these methods are reviewed briefly, followed by the applications and examples in a Bayesian framework.

In a frequentist/classical framework, except in the simplest cases, it is difficult or impossible to propagate classical confidence intervals through complex system models, such as reliability block diagrams, fault trees, and other logic models. In a Bayesian framework, on the other hand, posterior distributions are true probability statements about unknown parameters, so they may be easily propagated ...