A new approach for analyzing the reliability of logical loop based on goal-oriented methodology (GO)

To address the limitation of the standard GO method, the combination of “AND” and “OR” GO method (CAO-GO) is proposed based on Boolean algebra theory and the standard GO method. The principles of CAO-GO are theoretically analyzed. The state combinations of components and input/output signal flows are detailed. The logical relationships and reliability parameters of signal flows are mathematically derived. The correctness and capability of CAO-GO are verified by applying it to solve three typical examples. CAO-GO may be considered theoretically sound and practical for the reliability analysis on engineering system with logical loops, especially, the practical system with some specific material flows. The process of applying CAO-GO does not introduce other theory or operation different from the standard GO method. As a result, it conserves the intuitiveness and convenience of the standard GO method. So CAO-GO is easier for a reliability analyst to comprehend and use.