Reliability calculation under seasonally varying failure rate

This paper treats of the analytical solution of reliability problems in the special case when the failure rate acting on an object is a periodic piecewise constant function of time. It is proposed that the nonstationary failure rate be substituted by a stationary one. The formula intended for calculation of this fictitious equivalent stationary failure rate is derived. This makes possible the finding of approximate solutions of reliability problems in an analytical form convenient for applications in the sphere of engineering and for the following analysis. A simplistic example is used to demonstrate the proposed approach.