Reliability Assessment for Dependent Competing Failure Process with Shifting-Threshold and Imperfect Shock Model

In this article, we presented a reliability assessment method based on dependent competing failure model. In this model, we considered two failure processes: 1) soft failure caused by random degradation process; 2) hard failure caused by random shock process. And these two processes are dependent: 1) The shock process will accelerate degradation process; 2) After a certain number of shocks, the hard failure threshold will decrease; 3) with the degeneration of system, the probability of occurrence of the shock process will increase. In present research, most studies consider that every arriving shock will accelerate the degradation process, but because of the system resistance, not all shocks accelerate the degradation. Taking this into consideration, we research the shock process based on imperfect shock model. Finally, we verified this new method. And the results show that this method we presented is suitable to model the system failure behaviors.