This article presents a new redundancy strategy for system reliability optimization. The proposed strategy is a general form of a recently introduced strategy called “Mixed Strategy.” Adding parallel redundant component is a common approach in order to improve the reliability of a specific system. This approach is known as redundancy allocation problem. The redundancy allocation problem is a challenging issue for many researchers which has been subjected to investigation in this study. Generally, in the redundancy allocation problem, there are three redundancy strategies for using the redundant components: active, standby and mixed. The new emerging mixed strategy is a general form which involves both active and standby strategies. In this article, a general form of the mixed strategy called “K-mixed,” will be introduced and mathematical formulation for calculating the reliability of this new strategy will be presented. In order to evaluate the efficiency of the K-mixed strategy, a single specific subsystem with four components will be used and reliability of the subsystem will be computed by considering all three previous strategies and the new one. To have a better understanding about the performance of these four strategies, the effect of switch reliability and component reliability will be further examined.
A multi-objective reliability-redundancy allocation problem with active redundancy and interval type-2 fuzzy parameters
