Optimal system structure with different imperfect fault coverage

This paper studies the optimal system structure with consideration of different types of imperfect fault coverage. Due to imperfect fault coverage, the reliability of redundant systems cannot be enhanced unlimitedly with the increase of redundancy. Thus it is essential to study the optimal structure of redundant systems. A multi-state seriesparallel system with both redundancy parallelization and task sharing parallelization is considered. It is assumed that the uncovered failures in the elements belonging to the group of elements sharing the same task can cause failure of the entire group. The optimal trade-off between the two kinds of parallelization is studied based on various fault coverage models. Examples are presented to illustrate applications of the results.