The objective of this paper is to study the M/M/R machine repair queueing system with mixed standbys. The life-time and repair time of units are assumed to be exponentially distributed. Failed units are repaired on FCFS basis. The standbys have switching failure probability q (0≤q≤1). The repair facility of the system consists of R permanent as well as r additional removable repairmen. Due to i...

This paper deals with bi-level control policy and queuing analysis of a machine repair problem. The model is developed by incorporating mixed standbys (cold and warm), reneging, set up and vacation time. The repair facility consists of two heterogeneous repairmen in the system. The life and repair time of the failed units and also their set up times are assumed to be exponentially distributed. ...

A parallel (2, n – 2)-system is investigated here where two units start their operation simultaneously and any one of them is replaced instantaneously upon its failure by one of the (2; n – 2) warm standbys. We assume availability of n non-identical, non-repairable units. The unit-lifetimes in full operational mode and in partial operational mode have general distribution functions Gi and Hi (i...

The crew rostering problem arises in public transport bus companies, and addresses the task of assigning a given set of anonymous duties and some other activities, such as standbys and days off, to drivers or groups of drivers, without violating any complex labor union rules. Additionally, the preferences of drivers are considered during the assignment. The plan generated for each driver/group ...

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...

This paper deals with the transient analysis of K-out-of-N: G system consisting of Noperatingmachines. To improve system reliability, Y cold standby and S warm standbys spares areprovided to replace the failed machines. The machines are assumed to fail in multiple modes. At leastK-out-of-N machines for smooth functioning of the system. Reliability and mean time to failure areestablished in term...