Approximations to System Reliability Using a Modular Decomposition

Since the computation of system reliability is often a difficult task, approximation procedures are needed. Esary and Proschan have developed a procedure for finding a lower bound estimate of the system reliability of a coherent structure. In this paper, a new lower bound procedure based on the modular decomposition of a coherent structure is proposed. It is shown that this procedure provides a sharper lower bound estimate of the system reliability of a coherent structure than the Esary Proschan procedure and is computationally more efficient.