Applying an approximate Tω (the weakest t-norm) fuzzy GERT to evaluate two-unit standby redundant system reliability.

Abstract: Standby redundant system is a powerful tool to enhance the reliability, availability, quality, and safety of operational plants. This study proposed an approximate Tω (the weakest t-norm) fuzzy Graphical Evaluation and Review Technique (GERT) simulation technology to simulate two-unit standby redundant system reliability. The approximate fuzzy arithmetic operations employ principle of interval arithmetic under the Tω arithmetic operations. Therefore, the novel fuzzy arithmetic operations may obtain fitter decision values, which have smaller fuzziness accumulating, under vague environment. In numerical examples the approximate fuzzy arithmetic operations has evidenced that it can successfully calculate results of fuzzy operations as interval arithmetic, and can more effectively reduce fuzzy spreads. In the real fuzzy repairable reliability model the performance also shows that the approximate fuzzy arithmetic operations successfully simulate/analyze the two-unit standby redundant system reliability and obtain more confident fuzzy results under vague environment. [Copyright &y& Elsevier]