Testing and preventive maintenance scheduling optimization for aging systems modeled by generalized renewal process

Abstract

The use of stochastic point processes to model the reliability of repairable systems has been a regular approach to establish survival measures in failure versus repair scenarios. However, the traditional processes do not consider the actual state in which an item returns to operational condition. The traditional renewal process considers an "as-good-as-new" philosophy, while a non-homogeneous Poisson process is based on the minimal repair concept. In this work, an approach based on the concept of Generalized Renewal Process (GRP) is presented, which is a generalization of the renewal process and the non-homogeneous Poisson process. A stochastic modeling is presented for systems availability analysis, including testing and/or preventive maintenances scheduling. To validate the proposed approach, it was performed a case study of a hypothetical auxiliary feed-water system of a nuclear power plant, using genetic algorithm as optimization tool.

Evaluation of a proposed optimization method for discrete-event simulation models

“…As proof of this, some of today's top simulation packages, including ProModel's SimRunner , Siemen's WizardGA , AutoMod's AutoState , use Genetic Algorithms. Damaso & Garcia (2009) state the use of evolutionary techniques is justified when optimization problems are combinatory in nature; this is the case with simulation optimization, where input variable combinations are tested in order to find the most desirable output results (Harrel, Ghosh & Bowden, 2004). This investigation's proposed optimization method utilized a genetic algorithm (GA).…”

Using ELECTRE TRI to support maintenance of water distribution networks

“…This approach considered criteria related to technical aspects, water quality and social aspects, which led to the conclusion that although the model has been applied to a small town, fits perfectly to similar problems involving large cities. Damaso & Garcia (2009) presented an approach to the availabil-FLAVIO TROJAN and DANIELLE COSTA MORAIS 425 ity of the aging model systems in standby mode, based on the generalized renewal process, to be used to optimize the scheduling of testing and preventive maintenance. As well, the aim of this study is to provide a tactical view on the actions to be implemented, the model of Damaso & Garcia (2009), could be incorporated into a second stage of this work, when the actions are effectively implemented in order to promote a more detailed study for preventive maintenance.…”