Service reliability evaluation of large scale multi-state weighted k-outof- n systems
Résumé
Fault tolerance techniques are widely used to enhance the service reliability of important systems. In recent years, k-out-of-n systems have received considerable attention from researchers in the field of fault tolerance. The service reliability of a k-out-of-n system can be evaluated by the Universal Generating Function (UGF) algorithm. However, the algorithm may not be effective in a large-scale kout- of-n system because of its time complexity. In fact, we have found that some unnecessary calculations in existing UGF approaches can be eliminated by exploiting the concept of ordinary branch-and-bound technique. Based on this concept, we propose an algorithm that can evaluate the reliability of multi-state weighted k-out-of-n systems more efficiently than existing approaches. We demonstrate the algorithm's efficacy via a numerical example. The numerical analysis results show that it performs well when the weight range of the k-out-of-n system is relatively large, such as in a rope transportation system in a shipyard, the multi-engine system on an aircraft, and the power output of generators in power station