“…Zhang et al [24] studied the reliability and maintenance costs of a deteriorating system which may fail due to its degradation or random shocks. Janani [25] analyzed a queueing system with a server and two types of failure. Wu and Wu [26] studied a two-component system under Poisson shocks, where the repair time of the failed components and the repairman's vacation time are assumed to obey the general distributions.…”