This paper deals with machine repair problem with balking and reneging. There is provision of mixed standby (warm and cold) components to replace the failed machines. The lifetime and repair time are assumed to have exponential distribution. Birth-death technique is suggested to obtain the queue size distribution in explicit form. A repair facility of C permanent repairmen is facilitated to rep...

Abstract: In this paper, we study the reliability measures of a repairable system with M operating units, W warm standby units, and R repairmen in which switching failures and reboot delay are considered. It is assumed that there is a significant failure probability q in the switching process. Failure times of an operating unit and of a standby unit are assumed to be exponentially distributed w...

In this paper we consider a simple kind of the statechart language which is supported by the CASE tool Rhapsody. This kind of statecharts is already modeled in [4] using graph transformation. In accordance to [4], we allow hierarchical composition (sub-states and super-states) and parallel composition (combination of states by conjunction). A sample statechart is shown by Figure 1. It models th...

This study is concerned with the performance modeling of a fault tolerant system consisting of operating units supported by a combination of warm and cold spares. The on-line as well as warm standby units are subject to failures and are send for the repair to a repair facility having single repairman which is prone to failure. If the failed unit is not detected, the system enters into an unsafe...

In this paper, we analyze spare parts supply for a system with a “k-outof-N” redundancy structure for key components, different standby policies (cold, warm and hot standby redundancy) and local spare parts inventories for sub-components. We assume multiple part types (sub-components) that fail randomly with exponentially distributed interfailure times. Due to the standby policies and the limit...

In this research, a new hybrid model for the redundancy allocation problem (RAP) in series-parallel configuration with k-out-of-n subsystem is presented. given model, policy set to an active, warm standby, or no redundancy. standby policy, imperfect switch detected component's failure and replaced fail component one. So, subsystems' one of model's decision variables. We presented objective func...

Redundancy or standby is a provision which plays an important role in improving the reliability of engineering systems. This investigation deals with the reliability and sensitivity analysis of a repairable system (consisting of hardware and software components) with warm standbys and switching failures. The failure and repair rates of the components are assumed to follow exponential distributi...