Testing the steady state availability based on data from a fixed length test
A life test for a repairable system is considered in which the system occupies one of two mutually exclusive states: up (=fully operational) or down (=not operational due to failure, and being repaired). At time zero, the system is switched on and begins in the up or down state. The system alternates between the two states, entering the down state from the up state upon failure, and entering the up state from the down state upon successful repair. The successive visits to the up states have durations and the successive visits to the down states have durations It is assumed that the Xi and YXi areall mutually independent exponentially distributed random variables with the X's having mean θ≤0 and the Y's having mean τ≤0. The steady state availability is . Hypothesis.