A novel approach for analyzing the reliability of series-parallel system using credibility theory and different types of intuitionistic fuzzy numbers

The main objective of this paper is to present an alternative method for computing the membership function of the system under intuitionistic fuzzy set environment. Conventionally, it is not always easy to obtain the system reliability for components with different individual failure probability density function due to necessary but complicated combination and integration of various probability density functions. Also, in the literature, it is assumed that failure rates of all the components of a system follow the same type of fuzzy set which is rarely occurring in the practical situations. Thus, this paper addresses the fuzzy system reliability analysis to construct the membership and non-membership functions by considering the different types of intuitionistic fuzzy failure rates. Functions of intuitionistic fuzzy numbers are calculated using credibility theory. The effectiveness of the proposed approach is illustrated with analyze of the fuzzy reliability of series, parallel and series-parallel systems using different types of intuitionistic fuzzy failure rates. The computed results from the analysis have a less range of uncertainty as the comparability of existing results.