This paper investigates the availability characteristics and the reliability of a three-dissimilar-unit repairable system with two diierent repair facilities. Under some practical assumptions, we obtain the explicit expressions of the state probabilities of the system, and then the explicit expressions of the following performance measures of the system: (1) the pointwise and steady-state avail...

This paper presents a high quality simulation tool that evaluates the efficiency of redundancy algorithms (RAs) for repairable memory devices. The tool can generate various faulty memory models to be analyzed by a given RA. Furthermore it can provide useful information for the feedback to RA under evaluation when the RA fails to repair any theoretically repairable model. The approach and the ex...

Here we examine an active redundant system with scheduled starting times of the units. We assume availability of n non-identical, non-repairable units for replacement or support. The original unit starts its operation at time s1 = 0 and each one of the (n 1) standbys starts its operation at scheduled time si (i = 2, . . .,n) and works in parallel with those already introduced and not failed bef...

In repairable redundant systems the failed units can either be repaired or replaced by identical standby to reduce the system down time. The failed units are inspected for repair/replacement. In this paper, two stochastic models for 2(k)-out-of-3(n) redundant system of identical units with repair and inspection are examined stochastically. The system is considered in up-state only if 2(k)-out-o...

This paper documents a simulation study undertaken to gain insights into the Vari-Metric multi-echelon repairable inventory optimization method. The method was analyzed in the context of the Coast Guard’s fleet of fixed and rotary wing aircraft, for which operational availability is the key performance metric. Failure rates of parts in this system exhibit variance-to-mean ratios higher than one...

In the present investigation, we deal with the reliability characteristics of a repairable system consisting of two independent operating units, by incorporating the coverage factor. The probability of the successful detection, location and recovery from a failure is known as the coverage probability. The reboot delay and common cause shock failure are also considered. The times to failure of t...

A reliability system submitted to external and internal failures, that can be repairable or non-repairable, with degradation levels, and with sojourn times phase-type distributed, is considered. Repair is not as good as new, and the repair of internal failure follows policy N, that is, after N completed repairs the system is replaced by a new one to the following failure, repairable or not. For...

We consider a manufacturer of complex machines that offers service contracts to her customers, committing herself to repair failed spare parts throughout a fixed service period. The suppliers of spare parts often discontinue the production of some parts as technology advances and ask the manufacturer to place a final order. We address the problem of determining final orders for such spare parts...