Int J Performability Eng ›› 2007, Vol. 3 ›› Issue (2): 225-230.doi: 10.23940/ijpe.07.2.p225.mag

• Original articles • Previous Articles     Next Articles

A Closed-formula for Mean Time Between Failures of Minimal Repaired Systems under Weibull Failure Distribution


  1. University Politehnica of Bucharest, Faculty of Power Engineering
    313 Splaiul Independentei
    060042 Bucharest, Romania


We examine the behaviour of maintained systems that deteriorate according to a Non Homogenous Poisson Processes (NHPP). The system failures are selfannouncing; after each failure only a minimal repair is made so that the system failure rate l(t) (corresponding to Weibull failure distribution Weib (a,b)) is not disturbed. We propose a closed-formula for computing Mean Time between Failures as function of Mean Time to First Failure MTTF and the shape parameter b of Weibull failure distribution. This can lead to evaluate better the graceful degradation of complex system (power stations, airplanes, computers, etc.) with a minimal repair maintenance policy between replacements or overhauls.
Received on June 13, 2006
References: 05