Reliability Measures of a 1-Out-of-2 System with Standby and Delayed Service

In this paper, reliability measures of a stochastic model developed for a 1-out-of-2 system with single standby are obtained by considering delayed service. The system consists of three identical units, two are initially operative and one is in cold standby. The system remains operative if any one of the units operates and system fails at the failure of the entire units. Each unit is in either operative or complete failure mode. Single server carries out the repair of failed unit with delay while reaching the system. However, server visits the system immediately if all the three units fail. Switch devices are faultless and repaired unit works similar to new one. Random variables of failure time, repair time and arrival time (or delay time) of the server are statistically independent. Semi-Markov process and regenerative point technique are used to evaluate mean time to system failure (MTSF), steady state availability, and busy period of the server and profit of the system. The trend of various reliability measures for a particular case are shown graphically.