Cost-benefit analysis of a n-unit two-server system with preventive maintenance
Abstract This paper deals with the cost-benefit analysis of a 1 out of n : G system with two servers, one for preventive maintenance (PM) and one for repair. All standby units are cold. An operating unit is taken off for repair when it fails or for PM when a PM action is due. If a unit that needs service (PM or repair) finds the corresponding server busy it enters a first-come-first-served queue. When a unit is taken off for service and no standby is available, the system goes down. Expressions for steady-state expected up-time, time spent on PM and time spent on repair are obtained. These, along with linearity assumptions on the revenue and costs, are used to obtain an expression for the steady-state expected net revenue per unit time. A special case with age replacement is taken up for study and numerical results are presented.