Reliability for Engineers

The book starts with a description of how systems are developed and the place of reliability in this development. This theme is taken up again in chapter 15, "Specification, Design and Manufacture of Reliable Systems". Chapters 3 and 4 are devoted to the statistics of failure; the statistics are related to component failure, since it is the failure of one or more components which causes system failure. However, much of the statistical treatment is applicable to systems as well. The way that past failure statistics can be used to predict future failure patterns is described. The failure of components is examined in chapter 4 with reference to the effects of environment, power dissipation and complexity on probability of failure. Sources of failure data are listed and a description is given of how they are used. The simplest reliability system is a "series" system in which the failure of any one component causes total system failure. The series reliability system is analyzed in chapter 6 and the way to predict failures on a probabalistic basis is described. The effects of repair are also considered.
Chapter 7 consists of a brief survey of methods of increasing system reliability and this serves as an introduction to the next two chapters on fault-tolerant systems. These are systems in which the failure of one, or possibly more components does not necessarily cause system failure. The effect on a system of maintenance (corrective and preventive) in chapter 10 is an expansion of the topic first introduced in chapter 6. Markow analysis (chapter 11) is a powerful method of system analysis based upon a diagram giving the various states which a system can take following various component failures. This introduces chapter 12 which is devoted to spare parts provisioning. Software reliability is a vast subject in its own right and only a brief discussion of the problem and some suggestions for alleviation of some of the problems associated with it are contained in chapter 13.