A New Method for Finding Modules of Fault Trees

Fault Tree Analysis (FTA) is widely applied to evaluating failure probability related to complex engineering system. A large number of minimal cut sets (MCSs) may be involved in FTA when dealing with complex system, and searching for these MCSs may be time-consuming. Modules of fault trees have been employed to reduce the computational burden relevant to basic operations of fault trees. Based on the Graph Theory to find In-degree and Out-degree of the tree, this paper proposes an improved method to find modules of a fault tree, and the complexity associated with the proposed method is linear when the number of nodes and edges in the fault tree increases, which can remarkably reduce the module searching time. Comparisons between the proposed method and available ones are given. An experiment shows that the proposed method is efficient.