Based on the probability distribution model of fault replacement of (s
Q)
an optimal replenishment cycle algorithm targeted to minimize the replenishment cycle utility and an optimal ordering cycle algorithm targeted to minimize the ordering cycle utility are introduced
they not only keep the saving expense merit and the improving availability merit in (s
Q)
but also overcome the disadvantages of lacking of adjusting ability to overstocking of capital losses
device deprecation losses
the shortage loss and the surplus maintenance losses.The simulation result verifies our mechanism merits well.