ABSTRACT
In degradation modeling, a predefined threshold value is considered to identify the time-to-failure. Further, the degradation approach provides more accurate reliability estimates compared to the traditional failure time approaches. In traditional deterministic models, system behavior is defined by a set of equations that can describe with certainty how the system performance will evolve over the period of time. The chapter presents the different types of continuous state stochastic processes, degradation modeling with those processes, and selection of appropriate stochastic process. It describes the discrete state stochastic processes with case examples. The chapter summarizes the application of stochastic processes in degradation modeling to evaluate the system reliability. The continuous state stochastic process represents the continuity of the system changes as a function of time and implies a well-behaved sample path property to further analysis. The gamma process represents the degradation behavior in a form of cumulative damage where the deterioration occurs gradually over the period of time.
