Impact of different minimal path set selection methods on the efficiency of fault tree decomposition

In recent papers a new method to analyse complex fault trees was proposed. The fault tree is decomposed into a set of mutually exclusive simpler fault trees up to their dimensions are compatible with the available computational resources. Then, the results of the exact analysis of all simpler trees are composed to obtain the exact results for the original un-decomposed fault tree. The decomposition is based on the events making up a Minimal Path Set (MPS). An MPS is a set of components such that if they are all working the Top event is not verified (i.e. any minimal cut set (MCS) contains at least one event of the MPS). This means that it is possible to partition all MCSs into a given number of sets. In general, complex tree can be decomposed in as many ways as the number of its MPSs. The efficiency of the decomposition method is sensitive to the composition of the MPS. Hence, the problem is the determination of the MPS that minimises the time needed for decomposition based analysis of fault tree. Due to the heuristic nature of this problem it is necessary to experimentally test a number of MPS selection algorithms in order to draw indications on the relatively “best” method(s).

MATUZAS Vaidas;  CONTINI Sergio; 

2011-11-03

Taylor & Francis

JRC64583