This article considers risk models related to disasters of complex engineering systems. It is proposed to include parameters of system vulnerability, survivability and security into risk models. Types of risk function for different disaster mechanisms are discussed. It is shown that the risk functions may have both exponential and power mode peculiarity. The mechanism of transformation of the exponential distribution into power mode (Pareto) distribution is determined.
Disaster, engineering systems, failure processes, probabilistic model, risk function
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