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Maintenance, Reliability, and Value

Value is often not considered in engineering decisions; Dr. Marais applies concepts from financial analysis, such as discounted cash flow valuation, and techniques from economics such as hedonic analysis, to assess the impact of engineering and operating decisions on both traditional monetary value and non-monetary impacts (e.g., air pollution). This work focuses on the cost and benefit impacts of risk, reliability, and maintenance decisions.

Maintenance Modeling

In this work we explore how maintenance can be modelled, and the implications of modelling choices on optimization. We show how value could be brought into maintenance planning and how the value-optimization concept can be applied using Kijima models, a semi-Markov decision process, discounted cash flow techniques, and dynamic programming to identify the value-optimal maintenance actions for any given time and system condition. Most recently, we are comparing Kijima Type I and II models and their impact on optimization.


This work focuses on understanding how value can be brought into system reliability decisions and on how to better make decisions with imperfect data. In one of our projects, we are developing new ways of predicting component lifetimes, and, in another project, we are developing approaches to make better decisions on No Fault Found errors.