Control of repair rates in cold standby systems

This paper considers the reliability of a redundant system with cold standby and a single repair facility. It introduces some managerial controls and environmental constraints. Normally the repair rate is μ. However, on failure of the online unit the repair rate is geared up to a higher rate β>μ, if the repair facility is busy. It will stay at this higher level till the end of a random period or a repair completion, whichever occurs first. Some performance measures for a two unit cold standby system are obtained for the case of exponentially as well as arbitrarily distributed lifetimes, assuming all the other distributions to be exponential. Finally costs are taken into account explicitly and some static optimizations are considered.