Abstract
This chapter presents a numerical methodology to model and evaluate reliability, expected mission completion time, and expected total mission cost of 1-out-of-N: G standby sparing systems subject to periodic or non-periodic backup actions. The backups are performed to facilitate effective system recovery in the case of the occurrence of an online operating element failure. The methodology is applicable to dynamic data backup and retrieval times as well as nonidentical system elements with different time-to-failure distributions, different performance, and different standby modes. This chapter also presents applications of the methodology to a set of optimization problems that find the optimal backup distribution and/or element activation sequence, maximizing mission reliability or minimizing expected mission completion time or minimizing total mission cost. Examples are provided to illustrate the presented methodology as well as optimized solutions.