Maintenance Optimization Model Research Articles

An optimal maintenance model using a number of different actions

In this paper, we study an optimal maintenance model. The state of a system is determined by the distribution of its operating time. Whenever the system fails, a number of actions can be chosen, including the repair actions, the replacement actions and the action of discarding the system. The objective of this paper is to determine an optimal policy which maximizes the expected total discounted reward. By using the semi-Markov decision process approach, the method of successive approximations is suggested for determining the optimal reward function and the corresponding optimal policy.

Cost-Effectiveness-Based Priority Programming of Standardized Pavement Maintenance

A new optimization model and priority programming for pavement network maintenance and rehabilitation management are described. The optimization formulation is directed to determining the most cost-effective treatment action plans for preserving the pavement network’s serviceability above a specified level. The priority programming is conducted on a year-by-year basis, whereas a comprehensive prediction model for pavement deterioration versus time is considered. It is governed by traffic volume, pavement performance, a set of designed standard treatment alternatives, and budget limitations for network preservation. Each standardized pavement treatment alternative, including minor and major maintenance and rehabilitation, is defined by its effect on or level of improvement of the existing pavement surface quality and the corresponding costs. The effectiveness is calculated as a yearly product of the area under the performance curve and a minimum acceptable pavement condition index level multiplied by pavement length, traffic volume, and service days. The costs for applying any one of the standardized alternative treatments are expressed on a present worth basis. The prediction for each individual pavement deterioration is modeled as a time-related (nonhomogeneous) Markov transition process, in which pavement structural and functional improvements upon application of a treatment action are considered. The focus is on an integrated approach to pavement network preservation programming through cost-effectiveness analysis and comprehensive performance prediction in combination with standardized pavement treatment strategies. A case study application to a regional asphalt pavement network in Ontario, Canada, illustrates the use of the optimization model. The priority programming is practical and flexible with regard to the size of a road network, and the results of the example run are discussed.

An overall model for maintenance optimization

This paper presents an approach for identifying the optimal maintenance schedule for the components of a production system. Safety, health and environment objectives, maintenance costs and costs of lost production are all taken into consideration, and maintenance is thus optimized with respect to multiple objectives. Such a global approach to maintenance optimization requires expertise from various fields, e.g., decision theory, risk analysis and reliability and maintenance modelling. Further, a close co-operation between management, maintenance personnel and analysts is required to achieve a successful result. In the past this has been a major obstacle to the extensive use of proper maintenance optimization methods in practice, and techniques to promote the communication between the involved parties of the optimization process is an essential element in the suggested approach. A simple step by step presentation of the required modelling is provided. Contrary to most current methods of RCM (Reliability Centered Maintenance), the approach is based on an analytic model, and therefore gives a sound framework for carrying out a proper maintenance optimization. The approach is also flexible as it can be carried out at various levels of detail, e.g., adopted to available resources and to the managements willingness to give detailed priorities with respect to objectives on safety vs production loss.

Applications of maintenance optimization models: a review and analysis

In this paper we give an overview of applications of maintenance optimization models published so far. We analyze the role of these models in maintenance and discuss the factors which may have hampered applications. Finally, we discuss future prospects.

An optimal inspection–repair–replacement policy for standby systems

In this paper, an optimal maintenance model for standby systems is studied. An inspection–repair–replacement policy is employed. Assume that the state of the system can only be determined through an inspection which may incorrectly identify the system state. After each inspection, if the system is identified as in the down state, a repair action will be taken. It will be replaced some time later by a new and identical one. The problem is to determine an optimal policy so that the availability of the system is high enough at any time and the long-run expected cost per unit time is minimized. An explicit expression for the long-run expected cost per unit time is derived. For a geometric model, a simple algorithm for the determination of an optimal solution is suggested.

An optimal inspection–repair–replacement policy for standby systems

In this paper, an optimal maintenance model for standby systems is studied. An inspection–repair–replacement policy is employed. Assume that the state of the system can only be determined through an inspection which may incorrectly identify the system state. After each inspection, if the system is identified as in the down state, a repair action will be taken. It will be replaced some time later by a new and identical one. The problem is to determine an optimal policy so that the availability of the system is high enough at any time and the long-run expected cost per unit time is minimized. An explicit expression for the long-run expected cost per unit time is derived. For a geometric model, a simple algorithm for the determination of an optimal solution is suggested.

An optimal maintenance model for life cycle costing analysis

For many systems of nominal complexity, subsequent life-time operating and maintenance costs may amount to a larger sum than their acquisition cost. In this respect, reliability and maintainabiltiy constitute two direct and very predominant factors in life cycle costing analysis. This paper outlines the optimal maintenance schedule that minimises the system's future total expected maintenance cost. This minimum maintenance cost may be added to research and development costs, operation costs and salvage costs to obtain the total life cycle cost of the system. The case in which the system has constant failure rate is investigated under imperfect inspection policy.

Optimal maintenance models for systems subject to failure–A Review

AbstractThis paper is a state‐of‐the‐art review of the literature related to optimal maintenance models of systems subject to failure. The emphasis is on work appearing since the 1976 survey, “A Survey of Maintenance Models: The Control and Surveillance of Deteriorating Systems,” by W.P. Pierskalla and J.A. Voelker, published in this journal.