Читать книгу Reliability Analysis, Safety Assessment and Optimization - Enrico Zio - Страница 26

A random variable T follows the exponential distribution if and only if the pdf (shown in Figure 1.3) of T is

Figure 1.3 The pdf of the exponential distribution with λ=1.

(1.23)

where λ>0 is the parameter of the distribution. The cdf of the exponential distribution is

(1.24)

If T denotes the failure time of an item with exponential distribution, the reliability function will be

(1.25)

The hazard rate function is

(1.26)

The mean, μ, and variance, σ2 are

(1.27)