This thesis is finished during my Master of science and it consists of three chapters, in which we discuss the optimal replacement policy for a repairable system and the confidence interval for steady state availability of a specially system.

• 本文是在攻读硕士学位期间完成的,全文共分为三章,讨论了可修系统的最优更换策略及系统稳态可用度的区间估计问题。