Optimal replacement policy for a two-component cold standby system with repair priority

In this paper, a cold standby repairable system consisting of two dissimilar components and one repairman is examined. It was assumed that both Component 1 and Component 2, were not as good as new after repair, and Component 1 had repair priority. Under these assumptions, using the geometric process repair model, a discrete replacement policy N under which the system is replaced when the number of failures of Component 1 reaches N is considered. The problem was to determine an optimal policy N∗ so that the long-run average loss per unit time L( N) of the system was minimized. The expression L( N) was explicitly derived, and the corresponding optimal policy N∗ can be determined by minimizing L( N) with respect to N. A numerical example and the associated MATLAB computer program are given to illustrate the model—s applicability. Finally, conclusions are drawn for this study.