Burn-in is a widely used engineering method of elimination of defective items before they are shipped to customers or put into field operation. In conventional burn-in procedures, components or systems are subject to a period of simulated operation prior to actual usage. Then those which failed...

Burn-in is a widely used engineering method of elimination of defective items before they are shipped to customers or put into field operation. Under the assumption that a population is described by the decreasing or bathtub-shaped failure rate functions, various optimal burn-in problems have...

In this article we compare combined stochastic risk processes and consider its applications to various fields of relevance. Initially, the problem is formulated in terms of optimal transportation under fatal risks which may cause the failure of the transportation. Various transportation policies...

Lim et al. (Commun. Statist. Theory Meth. 27 (4) (1998) 965) proposed the Bayesian imperfect repair model, in which a failed system is perfectly repaired with probability P and is minimally repaired with probability 1-P, where P is not fixed but a random variable with a prior distribution...

Offering warranty for a second-hand item stimulates the sales of the item, but at the same time, it accumulates additional warranty servicing cost. This additional cost can be reduced through actions that improve the reliability of the item, such as overhaul and upgrade. An upgrade action brings...

A bivariate competing risks problem is considered for a rather general class of survival models. The lifetime distribution of each component is indexed by a frailty parameter. Under the assumption of conditional independence of components the correlated frailty model is considered. The explicit...

Some properties of the mean residual lifetime (MRL) functions are studied. The main focus is on relative characteristics. It is proved that under certain assumptions the relative hazard rate ordering leads to the corresponding ultimate MRL ordering. This result is applied to stochastic...

It is well known that life expectancy can be expressed as an integral of the survival curve. The reverse - that the survival function can be expressed as an integral of life expectancy - is also true.

Vaupel (1998) posed the provocative question, “When it comes to death, how do people and flies differ from Toyotas?†He suggested that as the force of natural selection diminishes with age, structural reliability concepts can be profitably used in mortality analysis. Vaupel (2003) went...

Cohort measures, describing a lifetime random variable are easily and unambiguously obtained using standard tools. On the contrary, the lifetime random variable, and therefore life expectancy, for the period setting cannot be unambiguously defined without additional simplifying assumptions. For...