Fuzzy Bayesian network to model safety systems performance

This article, targets the problem of uncertainty in assessing unavailability of systems, using fuzzy Bayesian networks. The elementary probabilities usually considered in Bayesian networks are replaced by fuzzy numbers. It allows experts to express their uncertainty about the basic parameters of systems and to evaluate the impact of the uncertainty on the safety systems performance. We will demonstrate how the uncertainty on some characteristic parameters values causes significant variations on the systems unavailability. In order to highlight the comparison and to show the exactness of the approach, we propose a Monte Carlo sampling approach where we consider triangular probability distribution of common cause failures factors.