Articoli di riviste: "Operation and maintenance policy"

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Shin, Jong-Ho, e Hong-Bae Jun. "On condition based maintenance policy". Journal of Computational Design and Engineering 2, n. 2 (7 gennaio 2015): 119–27. http://dx.doi.org/10.1016/j.jcde.2014.12.006.

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Abstract In the case of a high-valuable asset, the Operation and Maintenance (O&M) phase requires heavy charges and more efforts than the installation (construction) phase, because it has long usage life and any accident of an asset during this period causes catastrophic damage to an industry. Recently, with the advent of emerging Information Communication Technologies (ICTs), we can get the visibility of asset status information during its usage period. It gives us new challenging issues for improving the efficiency of asset operations. One issue is to implement the Condition-Based Maintenance (CBM) approach that makes a diagnosis of the asset status based on wire or wireless monitored data, predicts the assets abnormality, and executes suitable maintenance actions such as repair and replacement before serious problems happen. In this study, we have addressed several aspects of CBM approach: definition, related international standards, procedure, and techniques with the introduction of some relevant case studies that we have carried out.

2

Bányai, Ágota. "Energy Consumption-Based Maintenance Policy Optimization". Energies 14, n. 18 (9 settembre 2021): 5674. http://dx.doi.org/10.3390/en14185674.

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The optimal predictive, preventive, corrective and opportunistic maintenance policies play an important role in the success of sustainable maintenance operations. This study discusses a new energy efficiency-related maintenance policy optimization method, which is based on failure data and status information from both the physical system and the digital twin-based discrete event simulation. The study presents the functional model, the mathematical model and the solution algorithm. The maintenance optimization method proposed in this paper is made up of four main phases: computation of energy consumption based on the levelized cost of energy, computation of GHG emission, computation of value determination equations and application of the Howard’s policy iteration techniques. The approach was tested with a scenario analysis, where different electricity generation sources were taken into consideration. The computational results validated the optimization method and show that optimized maintenance policies can lead to an average of 38% cost reduction regarding energy consumption related costs. Practical implications of the proposed model and method regard the possibility of finding optimal maintenance policies that can affect the energy consumption and emissions from the operation and maintenance of manufacturing systems.

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Ye, Meng-Hua. "Optimal replacement policy with stochastic maintenance and operation costs". European Journal of Operational Research 44, n. 1 (gennaio 1990): 84–94. http://dx.doi.org/10.1016/0377-2217(90)90317-5.

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Mosser, Segolene Clemence Marie. "Maintenance modelling and optimization in the industry 4.0 context: Applications to the maintenance and design of industrial vehicles". Sustainable Engineering and Innovation 3, n. 2 (6 agosto 2021): 130–38. http://dx.doi.org/10.37868/sei.v3i2.id148.

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This paper focused on the maintenance problems encountered by industrial vehicles within the Volvo Group. The main goal of the research on this subject was to propose to customers’ a personalized maintenance offer which adapts to their constraints while reducing the impact on the operating costs. To achieve this, a policy has been developed. This policy works on the dynamic gathering of information using both the available monitoring information and the knowledge of the multi-component system. Its objective is to guarantee to the customer the autonomy of its system over given periods of operation while minimizing the total cost of maintenance. The paper showed that the policy developed does indeed reduce the total maintenance cost compared to the previous policy used within the Volvo group. Nevertheless, this policy still has room for improvement.

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Yang, Seungbong. "Optimized operation of regional reserve forces in a changing future security environment". Journal of Advances in Military Studies 4, n. 3 (31 dicembre 2021): 21–51. http://dx.doi.org/10.37944/jams.v4i3.121.

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The Republic of Korea Reserve Forces (ROKRF), established in 1968, continue to function through continuous changes such as improving laws and systems and optimizing organizations while complying with social and policy changes. However, the reduction of standing forces, changes in the operating environment, and the reduction of reserve forces required to carry out operations require the re-establishment of the concept of operation of regional reserve forces. In this study, we aimed to diagnose the phenomenon of regional reserve groups and derive an optimized operation plan for regional reserve groups in consideration of changes in the future security environment, operation support system, and law and order system. The operating system presented the mission of establishing local reserve forces suitable for the operating environment, organization, and organization maintenance for the future as well as maintenance and development of combat power through education and training. Finally, in the law and order system section, a plan to revise laws was proposed in consideration of the task of operating and constructing regional reserve forces and re-establishing them.

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Shang, Lijun, Xiguang Yu, Liying Wang e Yongjun Du. "Design of Random Warranty and Maintenance Policy: From a Perspective of the Life Cycle". Mathematics 10, n. 20 (11 ottobre 2022): 3723. http://dx.doi.org/10.3390/math10203723.

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Driven by digital technologies, it is possible that high-tech equipment management personnel use monitored job cycles to ensure products’ operation and maintenance over their life cycle. By means of monitored job cycles, this paper designs two categories of random maintenance policies: a two-stage two-dimensional free repair warranty (2DFRW) policy and a random hybrid periodic replacement (RHPR) policy. The 2DFRW policy is performed to ensure the product’s operation and maintenance over the warranty stage. Under such a policy, a product is minimally repaired at each failure, and regions of the second-stage warranty are set to be diverse to remove all inequities produced by limitations of the first-stage warranty. The warranty cost of two-stage 2DFRW is built and discussed. The RHPR policy is modeled to ensure the product’s operation and maintenance over the post-warranty stage. Under this policy, depending on the final expiry of the two-stage 2DFRW, a bivariate random periodic replacement (BRPR) policy and a univariate random periodic replacement (URPR) policy are skillfully used to reduce the maintenance cost over the post-warranty stage and maximally extend the residual useful time of the product through the warranty. The expected cost rate over the product’s operation and maintenance cycle is derived on the basis of renewal rewarded theorem. The optimal RHPR policy is analyzed by minimizing the cost rate. The presented models are numerically analyzed to explore hidden characteristics.

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Righter, Rhonda. "OPTIMAL MAINTENANCE AND OPERATION OF A SYSTEM WITH BACKUP COMPONENTS". Probability in the Engineering and Informational Sciences 16, n. 3 (22 maggio 2002): 339–49. http://dx.doi.org/10.1017/s0269964802163054.

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We consider a system with heterogeneous unreliable components that requires only one component to be turned on in order for it to operate. Repair workers may have different skills and may be unavailable for random periods of time. The problem is to determine a usage and repair policy to maximize system availability. We give conditions under which the optimal usage policy is to always use, or turn on, the component with the shortest repair time, and the optimal repair policy is to always repair the most reliable component (with the smallest failure rate). We fully characterize the optimal policy when there are only two components. Our system is equivalent to a closed system with multiple single-server queues, where the objective is to minimize server idle time at one of the queues.

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Pinceti, Paolo, Micaela Caserza Magro, Enrico De Paola, Pierluigi Firpo, Enrico Marino e Marco Antonelli. "CBM for a fleet of railway vehicles: infrastructure and algorithms". ACTA IMEKO 5, n. 4 (30 dicembre 2016): 56. http://dx.doi.org/10.21014/acta_imeko.v5i4.412.

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Data acquisition and communication technologies give the possibility of receiving and storing a huge amount of data from machinery and plants in operation. From these data it is possible to create a set of Key Maintenance Indicators (KMI) useful for optimizing the maintenance policy. Raw data from the field are to be processed and filtered for obtaining effective KMIs to use in algorithms aimed at discovering anomalies or abnormal operation of one or more machineries or plants.This paper presents a roadmap towards the Condition Based Maintenance of a fleet of railway vehicles. The paper associates to each maintenance policy its benefits and its requirements in terms of technological infrastructure and operating costs. Bombardier Transportation Italy started this roadmap a few years ago, for moving from a reactive maintenance policy to a proactive policy.Increasing the effectiveness of maintenance implies the sensorization of the machines and the creation of a network for funneling information from the machineries to the central maintenance room. A Company must find an equilibrium point between complexity and expected benefits.Results achieved by means of a specifically developed tool for data analysis applied to some sub-systems of the vehicles are presented.

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Bérenguer, C., A. Grall, L. Dieulle e M. Roussignol. "MAINTENANCE POLICY FOR A CONTINUOUSLY MONITORED DETERIORATING SYSTEM". Probability in the Engineering and Informational Sciences 17, n. 2 (27 febbraio 2003): 235–50. http://dx.doi.org/10.1017/s0269964803172063.

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We consider a continuously monitored system that gradually and stochastically deteriorates. An alarm threshold is set on the system deterioration level for triggering a delayed preventive maintenance operation. A mathematical model is developed to find the value of the alarm threshold that minimizes the asymptotic unavailability. Approximations are derived to improve the numerical optimization.

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Faidy, C., e J. P. Hutin. "Plant life management: an integral part of operation and maintenance policy". Kerntechnik 67, n. 4 (1 agosto 2002): 196–99. http://dx.doi.org/10.1515/kern-2002-0080.

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Abstract Electricité de France is now operating 58 PWR nuclear power plants that produce 75 % of electricity in France. Besides maintaining safety and availability on a routine basis, it is outmost important to protect the investment. That is the reason why EDF is devoting important resources to implement ageing management concern as an integral part of operation and maintenance programs (for example through appropriate data collection and analysis, specific repair and replacement projects and important anticipation efforts, taking in account the high level of standardisation of the units). A particular organisation has been set up to continuously observe and analyse all activities so as to make sure that ageing concern is correctly taken in account in strategies and that no decisions are susceptible to impair plant lifetime. This “lifetime program” is paying attention to technical issues associated with main components but is also dealing with issues related to economics and industry situation.

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Su, H. S., e J. D. Li. "Research and Simulation on Repairable Device Preventive Maintenance Control Policy". Applied Mechanics and Materials 743 (marzo 2015): 189–95. http://dx.doi.org/10.4028/www.scientific.net/amm.743.189.

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In consideration of the situation that the conventional preventive maintenance inspection cycle of the repairable device is not be changed as long as it is determined, based on continuous-time Markov processes, the repairable device preventive maintenance control strategy is studied. The preventive maintenance model is established, i.e., its state transition diagram, steady state value of the model is calculated, the control policy of device’s check rates based on device status is proposed, and the proposed control policy is simulated and confirmed using MATLAB. Simulation results show that under the proposed control policy rule, the actual operation curve of the system can well track the desired operation curve of the system, and finally can achieve the desired steady state value. Studies have shown that the method has some help to strengthen device maintenance management, improve device maintenance strategies, ensure that the device is repaired according to the state, and reduce maintenance costs of the device.

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Pinciroli, Luca, Piero Baraldi, Guido Ballabio, Michele Compare e Enrico Zio. "Deep Reinforcement Learning Based on Proximal Policy Optimization for the Maintenance of a Wind Farm with Multiple Crews". Energies 14, n. 20 (16 ottobre 2021): 6743. http://dx.doi.org/10.3390/en14206743.

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The life cycle of wind turbines depends on the operation and maintenance policies adopted. With the critical components of wind turbines being equipped with condition monitoring and Prognostics and Health Management (PHM) capabilities, it is feasible to significantly optimize operation and maintenance (O&M) by combining the (uncertain) information provided by PHM with the other factors influencing O&M activities, including the limited availability of maintenance crews, the variability of energy demand and corresponding production requests, and the long-time horizons of energy systems operation. In this work, we consider the operation and maintenance optimization of wind turbines in wind farms woth multiple crews. A new formulation of the problem as a sequential decision problem over a long-time horizon is proposed and solved by deep reinforcement learning based on proximal policy optimization. The proposed method is applied to a wind farm of 50 turbines, considering the availability of multiple maintenance crews. The optimal O&M policy found outperforms other state-of-the-art strategies, regardless of the number of available maintenance crews.

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Xia, Tang-Bin, Xin-Yang Tao e Li-Feng Xi. "Operation Process Rebuilding (OPR)-Oriented Maintenance Policy for Changeable System Structures". IEEE Transactions on Automation Science and Engineering 14, n. 1 (gennaio 2017): 139–48. http://dx.doi.org/10.1109/tase.2016.2618767.

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Martinod, R. M., Olivier Bistorin, Leonel Castañeda e Nidhal Rezg. "Joint optimisation of operation and maintenance policies in an urban ropeway transport systems context". International Journal of Quality & Reliability Management 36, n. 7 (5 agosto 2019): 1106–36. http://dx.doi.org/10.1108/ijqrm-10-2018-0292.

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Purpose The purpose of this paper is to propose a stochastic optimisation model for integrating service and maintenance policies in order to solve the queuing problem and the cost of maintenance activities for public transport services, with a particular focus on urban ropeway system. Design/methodology/approach The authors adopt the following approaches: a discrete-event model that uses a set of interrelated queues for the formulation of the service problem using a cost-based expression; and a maintenance model consisting of preventive and corrective maintenance actions, which considers two different maintenance policies (periodic block-type and age-based). Findings The work shows that neither periodic block-type maintenance nor an age-based maintenance is necessarily the best maintenance strategy over a long system lifecycle; the optimal strategy must consider both policies. Practical implications The maintenance policies are then evaluated for their impact on the service and operation of the transport system. The authors conclude by applying the proposed optimisation model using an example concerning ropeway systems. Originality/value This is the first study to simultaneously consider maintenance policy and operational policy in an urban aerial ropeway system, taking up the problem of queuing with particular attention to the unique requirements public transport services.

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Lagos, Carlos, Felipe Delgado e Mathias A. Klapp. "Dynamic Optimization for Airline Maintenance Operations". Transportation Science 54, n. 4 (luglio 2020): 998–1015. http://dx.doi.org/10.1287/trsc.2020.0984.

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The occurrence of unexpected aircraft maintenance tasks can produce expensive changes in an airline’s operation. When it comes to critical tasks, it might even cancel programmed flights. Despite this, the challenge of scheduling aircraft maintenance operations under uncertainty has received limited attention in the scientific literature. We study a dynamic airline maintenance scheduling problem, which daily decides the set of aircraft to maintain and the set of pending tasks to execute in each aircraft. The objective is to minimize the expected costs of expired maintenance tasks over the operating horizon. To increase flexibility and reduce costs, we integrate maintenance scheduling with tail assignment decisions. We formulate our problem as a Markov decision process and design dynamic policies based on approximate dynamic programming, including value function approximation, rolling horizon techniques, and a hybrid policy between the latter two that delivers the best results. In a case study based on LATAM airline, we show the value of dynamic optimization by testing our best policies against a simple airline decision rule and a deterministic relaxation with perfect future information. We suggest to schedule tasks requiring less resources first to increase utilization of residual maintenance capacity. Finally, we observe strong economies of scale when sharing maintenance resources between multiple airlines.

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Ab-Samat, Hasnida, e Shahrul Kamaruddin. "Opportunistic maintenance (OM) as a new advancement in maintenance approaches". Journal of Quality in Maintenance Engineering 20, n. 2 (6 maggio 2014): 98–121. http://dx.doi.org/10.1108/jqme-04-2013-0018.

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Purpose – This paper reviews the literature on opportunistic maintenance (OM) as new advance maintenance approach and policy. The purpose of this paper is to conceptually identify common principle and thereby provide absolute definition, concept and characteristics of this policy. Design/methodology/approach – A conceptual analysis was conducted on various literatures to clarify a number of principle and concepts as a method for understanding information on OM. The analysis involves the process of separating the compound terms used in the literatures into a few parts, analyse them and then recombining them to have more clear understanding of the policy. Findings – The paper discussed the maintenance approach, genealogy, principle, concept and applications of OM both in numerical analysis and real industry. OM policy is developed based on combination of age replacement policy and block replacement policy and in practical; OM is applied as the combination of corrective maintenance which is applied when any failure occurred, with preventive maintenance (PM) – a planned and scheduled maintenance approach to prevent failure to happen. Any machine shutdown or stoppages due to failure is the “opportunity” to conduct PM even though it is not as planned. The characterization of OM was provided in order to present its theoretical novelty for researchers and practical significance for industries. Practical implications – To date, there is no publication that reviews the OM in-depth and provides clear understanding on the topic. Therefore, this paper aims to show lineage of OM and the current trend in researches. This discussion will pave the way of new research areas on this optimal maintenance policy. Clear definition and principle of OM provided in this paper will trigger interest in its practicality as well as aid industries to understand and conduct OM in operation plant. Originality/value – This paper discussed the available literature about OM in various perspectives and scopes for further understanding of the topic by maintenance management professionals and researchers. Therefore, OM can be widely studied and applied in real industry as it is an effective and optimal maintenance policy.

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LIAO, GWO-LIANG, e BOR-LING SHAW. "OPTIMAL MAINTENANCE POLICY TO SUPPORT THE OPERATION OF MANUFACTURING WITH MINIMAL AND DELAYED REPAIR". International Journal of Reliability, Quality and Safety Engineering 16, n. 03 (giugno 2009): 235–47. http://dx.doi.org/10.1142/s021853930900337x.

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This work presents a periodic preventive maintenance (PM) model for a repairable system that undergoes minimal repair or delayed repair at each failure to keep a plant operating. Two PM types are performed, i.e. imperfect PM and perfect PM. The likelihood that PM is perfect depends on the number of imperfect maintenance activities have been performed since the last renewal cycle. Mathematical formulae for expected cost per unit time are developed. The optimal period for periodic PM, which minimizes cost, is identified. Various special cases are considered, including the maintenance learning effect. A numerical example demonstrates the effectiveness of the proposed model.

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Verbruggen, Theo, Luc Rademakers, Patrick Roost e Gerhard Dersjant. "Maintenance Manager to control operation and maintenance of offshore wind farms". International Journal of Environment and Sustainable Development 1, n. 4 (2002): 370. http://dx.doi.org/10.1504/ijesd.2002.002357.

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Ogwang, Patrick, e David Mwesigwa. "Road Asset Management System and Operation and Maintenance of World Bank-Funded Roads in Lira City, Uganda". International Journal of Public Policy and Administration 5, n. 2 (19 settembre 2023): 42–68. http://dx.doi.org/10.47941/ijppa.1441.

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Purpose: This study examined the contribution of road asset management to the operations and maintenance of World Bank funded roads in Lira City East division. Specifically, the study focussed on the effect of data collection, data management; and data analysis on operation and maintenance of World Bank funded roads in Lira City East division. Methodology: The study adopted a cross-sectional study design, which employed a mixed methods approach of both quantitative and qualitative methods. The study population consisted of 82 respondents, which involved political leaders, technical staff and city development forum (CDF) members of Lira City East division. Both the Simple random sampling technique and purposive sampling technique were used to select a sample of 71 participants. The researcher adopted Self-Administered Questionnaires to collect quantitative data and an interview guide to collect qualitative data. Both descriptive statistics, and inferential statistics were used to analyse numerical data. Content analysis was used to analyse qualitative data. Findings: The findings revealed a statistically significant positive relationship between road asset management and the operation and maintenance of World Bank funded roads. Further, it was revealed that data collection, data management and data analysis yield a significant effect on operation and maintenance of World Bank funded roads in Lira City East division. Unique contribution to theory, policy and practice: The study concluded that road asset management significantly affects operation and maintenance of World Bank funded roads in Lira City East division. It is encouraged that, for proper functionality and operations of world bank funded roads in Lira City division, the authorities of Lira City east division should do periodic inspection of all the roads, engage knowledgeable personnel in the collection of data on the conditions of all the road assets so that it can be used as a basis of decision making during the development of work plan and budgets for road maintenance. This study contributes an original and empirical-evidence of the contribution of road asset management on the operation and maintenance of roads in Lira City East division.

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Savsar, Mehmet. "Simulation Analysis of the Effects of Maintenance Policies on Manufacturing Line Productivity". Applied Mechanics and Materials 390 (agosto 2013): 646–52. http://dx.doi.org/10.4028/www.scientific.net/amm.390.646.

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A manufacturing line consists of a series of machines, which are subject to failures due to component deterioration and other random causes. While failures due to random causes are inevitable and need corrective maintenance (CM), failures due to component deterioration can be avoided by preventive maintenance (PM). Both types of maintenances can cause significant production losses, particularly if a proper PM policy is not practiced. Productivity calculations of multi-stage lines with storage units and maintenance operations can be quite complex. Furthermore, closed form solutions in equation forms are not possible when both preventive and corrective maintenances are incorporated into the model. In this paper, a simulation model is presented for a multi-stage line and line productivity is evaluated under different operating conditions and maintenance policies.

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Jiao, Zedong, Xiuli Du, Zhansheng Liu, Liang Liu, Zhe Sun, Guoliang Shi e Ruirui Liu. "A Review of Theory and Application Development of Intelligent Operation Methods for Large Public Buildings". Sustainability 15, n. 12 (16 giugno 2023): 9680. http://dx.doi.org/10.3390/su15129680.

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This article aims to systematically summarize the methods for intelligent operation of large public buildings, the integration and application of related technologies, as well as their development trends and challenges. (1) Background: In response to the rapid development and future needs of intelligent operation and maintenance, this study summarizes the development process of intelligent operation and maintenance in building operations, as well as relevant technical achievements and challenges; (2) Method: Quantitative and qualitative bibliometric statistical methods were used for overall analysis; (3) Result: Based on system theory, a B-IRO model was developed, and the current status of intelligent operation- and maintenance-related technologies and applications was sorted out. A framework for the entire industry was established, and future development trends were proposed as further research directions.

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Banyai, A. "Impact of agile, condition-based maintenance strategy on cost efficiency of production systems". Advances in Production Engineering & Management 18, n. 3 (30 settembre 2023): 317–26. http://dx.doi.org/10.14743/apem2023.3.475.

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Maintenance plays an increasingly important role in the life of production companies, as professional maintenance is an important prerequisite for the reliable operation of resources. A well-chosen maintenance strategy can make a major contribution to increased efficiency of production processes. The main goal of this research is to propose a novel optimization approach to define optimal maintenance strategy that ensures the efficient operation of the production process while reducing maintenance costs. The developed optimization method is based on Howard’s policy iteration and describes the objective of the planning as a Markov decision process. The novelty and the scientific contribution of the presented study is the application of Howard’s policy iteration methodology in a Markov decision process for agile, condition-based maintenance strategy optimization. As the results of the numerical analysis of the scenarios shows, the implementation of an optimized maintenance strategy based on the proposed approach can significantly increase the maintenance efficiency of the production process. The main reason for this is that the level and type of maintenance is always implemented depending on the current state of the system components, which reduces both the maintenance cost and the losses due to production downtime.

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Badía, F. G., M. D. Berrade e Clemente A. Campos. "Maintenance policy for multivariate standby/operating units". Applied Stochastic Models in Business and Industry 18, n. 2 (aprile 2002): 147–55. http://dx.doi.org/10.1002/asmb.459.

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Ma, Yuanjiang, Liang Hong, Taisong Qin, Xia Hao e Taiquan Tan. "Research on Monitoring Data Security Sharing Method for Hydropower Station Operation and Maintenance". Journal of Physics: Conference Series 2294, n. 1 (1 giugno 2022): 012009. http://dx.doi.org/10.1088/1742-6596/2294/1/012009.

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Abstract The computer monitoring system centrally and uniformly manages the hydropower stations in the basin, which has high operation efficiency. The current data security sharing methods can not solve the multi-party trust problems such as data ownership and data security. In this regard, a monitoring data security sharing method for hydropower station operation and maintenance is proposed. The monitoring data of hydropower station comes from multiple independent operation systems developed by different suppliers according to different application requirements. The multi-source data are integrated and processed to meet the interactive needs of users. User permission has the characteristics of dynamic change, which can identify the permission attributes. Create a trusted container based on the user ID, locate the monitoring data, and trace the source in data sharing and storage. The access policy is formulated by the data user and bound with the private key, while the data is given an attribute set during encryption. Each data user has a corresponding access policy and a private key corresponding to the access policy, so as to realize the security sharing of monitoring data. The test results show that the design method in this paper can effectively reduce the communication overhead and storage overhead, and has good computing performance.

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Boyapati, Raghuram P., Jahnavi Mehta e Paul Norris. "Same day cancellations of elective operations in a tertiary hospital in south-east England: a review of 11 000 patients in 1 year". British Journal of Healthcare Management 26, n. 1 (2 gennaio 2020): 27–33. http://dx.doi.org/10.12968/bjhc.2019.0029.

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Cancellations of elective operations have negative consequences, both for patients and the NHS. For the latter, reducing waiting times for surgical procedures remains a pressing concern, as does maintenance of adequate staffing. This study aimed to identify factors contributing to the cancellation of elective operations on the day of the procedure in order to suggest measures that could be taken to reduce these incidents. The retrospective details of just over 11 000 patients awaiting theatre admission for elective operations over a period of 1 year were obtained. The reasons behind last-minute operation cancellations were categorised as either patient factors or hospital factors. Data analysis suggested that the number of cancellations could be reduced by scheduling appointments with a senior doctor closer to the operation date.

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Rahmawati, Fajar Khanif, e Humaid Iswahyu Hafizh Rakha. "Advantages and Losses Analysis on Burning Hours by The Production Planning Control in Determining Time Implementation of Maintenance Activities". Vortex 2, n. 2 (30 giugno 2021): 1. http://dx.doi.org/10.28989/vortex.v2i2.981.

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Burning Hours is the one of policy in scheduling aircraft maintenance. With the burning hours the operator could performed aircraft maintenance before the due time. Burning Hours is indeed beneficial for flight operators to maintain the stability of the safety of the aircraft operation. Using the quantitative analysis method with the sample data’s from two aircraft, found that the burning hours affects to Burning Hours Cost loss for every aircraft meintenance activity. The value of Burning Hours Cost Loss and Potential Lost per Day needs to be considered by operators in scheduling maintenance activities, because it is possible that Burning Hours cannot be avoided in aircraft operation. Based on the data processing, the value of burning hours cost lost is not more than limit of potential lost per day. However it should also be considered if burning hours applied continuously will increase maintenance cost. Therefore, between maintenance planning department and the operation department should keep good coordination to minimize the burning hours cost loss. Keywords: Planning, Maintenance, Burning Hours

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Ge, En Shun, Qing Min Li e Ao Lin Huang. "Optimization of Condition-Based Maintenance Policy for Deteriorating System Based on Monte-Carlo Simulation". Advanced Materials Research 544 (giugno 2012): 44–48. http://dx.doi.org/10.4028/www.scientific.net/amr.544.44.

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Condition-based Maintenance (CBM) can not only efficiently improve the performance of deteriorating system but also guarantee the system operation safety. This paper assumes that the system state is periodically inspected, and a preventive maintenance is performed if the degradation level exceeds a threshold. The effect of maintenance is imperfect, which means that maintenance can restore the system state to somewhere between as good as new and as bad as old. The algorithm is presented to get the solution of long run cost based on Monte-Carlo simulation, and the joint optimization of inspection rate, the threshold value and the number of preventive maintenance activities is investigated for the minimization of long run cost rate. A case study is given to show the procedure of the maintenance model and simulation. Therefore, the correctness and rationality of the model are proved.

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Zhao, Xufeng, Khalifa N. Al-Khalifa, Abdel Magid Hamouda e Toshio Nakagawa. "What is Middle Maintenance Policy?" Quality and Reliability Engineering International 32, n. 7 (9 dicembre 2015): 2403–14. http://dx.doi.org/10.1002/qre.1944.

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Sugimura, Yoshihisa, Kazuhiko Ishiguro e Azuma Kato. "Possibility of Sustainable Entry into Overseas Port Operation Markets by Japanese Companies". Sustainability 14, n. 19 (26 settembre 2022): 12167. http://dx.doi.org/10.3390/su141912167.

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The Japanese government has set an overseas infrastructure deployment policy to involve Japanese companies in all upstream to downstream processes, that is, from project formation, procurement, and construction to operation and maintenance. Although Japanese companies have been hitherto involved in overseas port development through Official Development Assistance, their entry into overseas port operation projects has been limited, meaning the realization of the policy is not expected to be easy. This study thus examines the possibility of sustainable entry into overseas port operation markets by Japanese companies. Specifically, we review port governance in Japan, characteristics of the Japanese market in the global market, and the status of the participation of domestic terminal operators in Japan and overseas, and then identify the possibilities and methods of sustainable inclusion in the future overseas port operations by interviewing representative companies and the government. We finally provide future directions in terms of both increasing entry opportunities and improving the entry environment.

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An-Pi Chang e Jyh-Dong Lin. "DEFINING GREEN ROAD PROJECT MANAGEMENT SCOPE BY PDRI". International Journal of Engineering Technologies and Management Research 5, n. 10 (23 marzo 2020): 94–102. http://dx.doi.org/10.29121/ijetmr.v5.i10.2018.305.

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This study is about the project early operation content of the green road development, takes full account of the operation items of various stages of the life cycle, by the use of special case define the Project Definition Rating Index (PDRI). PDRI assessment framework, defining the need and scope of green road project development operations in the metropolitan area, and inquire set various assessment indicators of the work to complete building the overall indicator assessment system. From research in a policy aspect, as well as data collection out of instances of project case, research program obtains evaluation index operation item, and by semistructured interviews supplements insufficient evaluation index items and particularity needs. Research results will be beneficial to the application in the metropolitan regional overall development project. Building green road index evaluation system helps to avoid the environmental impact brought about by land development, reduce damage to people's life safety as a consequence from needs for road maintenance, alleviate future maintenance and management expenses, and is in line with the expected benefit of green road project sustainable development.

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Zhou, Xue, Yajian Ke, Jianhui Zhu e Weiwei Cui. "Sustainable Operation and Maintenance of Offshore Wind Farms Based on the Deep Wind Forecasting". Sustainability 16, n. 1 (29 dicembre 2023): 333. http://dx.doi.org/10.3390/su16010333.

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Offshore wind farms are becoming a pivotal solution to address the increasing energy demand worldwide and reduce carbon emissions to achieve a sustainable energy sector. Considering the higher operational and maintenance cost of offshore wind farms, it is important to make a good maintenance plan to guarantee the system’s reliability and reduce the total cost related to maintenance activities at the same time. Because maintenance planning is a long-term decision problem and the wind force is random, long-term wind force prediction is needed to help managers evaluate the loss caused by maintenances to be executed in the future. However, long-term wind force prediction is naturally complicated, which is much harder than the short-term (e.g., day-ahead) prediction widely investigated in the literature. In order to overcome this difficulty, we design a deep learning framework combining variational mode decomposition, a convolution neural network, long short-term memory network, and full-connected network. Using the public data from the city of Leeds, the prediction accuracy of the above framework is validated by comparing it with other prediction techniques. Then, the predicted wind force is input into the established optimization model determining preventive maintenances during a predefined period. Because the uncertainty of wind force is replaced by the prediction value, the optimization model can be established as a mixed-integer linear programing model, which only contains limited variables and can be solved quickly. Lastly, an abundance of numerical experiments are conducted to validate the effectiveness of the proposed optimization model, based on which some managerial insights are provided to the managers of offshore wind farms about the optimal operations and maintenance strategy. The research outcome will greatly promote the development of the wind power industry in the future.

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Monteiro Tavares, Carla Mericia, e Janusz Szpytko. "Maintenance strategy for vehicle with electronic fuel injection system". Journal of KONBiN 42, n. 1 (1 giugno 2017): 379–88. http://dx.doi.org/10.1515/jok-2017-0034.

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Abstract The introduction of new vehicles technology has been projected for advanced technologically places. Their use and operation, is a theme of big concern for developing countries. This work is part of the study for the creation and establishment of a maintenance strategy and policy, which will be acceptable in developing countries. The paper proposes a methodology for the identification of critical components of the electronic fuel injection system with failure mode, effects and criticality analysis tool (FMECA). With the elaboration of this work, was possible to visualize that the maintenance strategy for each component depends strongly on the availability of equipment for the diagnosis (fail detection). As future work, would be important to study the influence of others parameters that influence the maintenance and vehicle operation, as cost, environment, human aspect and vehicle operation. Another useful analyses would be, to analyses the data in a probabilistic interpretation in order to visualize influence of each component failure in the system failure.

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Damerdji, Rima Oudjedi, e Myriam Noureddine. "Maintenance Decision-Making Under the Cost Criterion and the Competing Risks Approach". International Journal of Decision Support System Technology 9, n. 1 (gennaio 2017): 32–48. http://dx.doi.org/10.4018/ijdsst.2017010103.

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The definition of an appropriated maintenance policy appears essential to avoid the system failures and ensure its optimal operation, while taking into account the criteria of availability and costs. This article deals with a maintenance decision-making for a system subject to two competing maintenance actions, corrective and preventive maintenance. To define this situation of dependent competing risks, the Alert Delay model seems well suited because it involves the notion of a delivered alert before system failure in order to perform preventive maintenance. This paper proposes an approach including both an extension of the Alert Delay model where the considered system follows an exponential distribution, and the total maintenance cost assessment of the system. These two concepts provide an aid decision-making to select the optimal maintenance policy based on the minimal cost. The proposed approach is validated in a computer system localized in a real industrial enterprise.

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Khanna, Aditi, Prerna Gautam, Biswajit Sarkar e Chandra K. Jaggi. "Integrated vendor–buyer strategies for imperfect production systems with maintenance and warranty policy". RAIRO - Operations Research 54, n. 2 (27 febbraio 2020): 435–50. http://dx.doi.org/10.1051/ro/2019029.

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Collaboration has evolved as a key component of many modern supply chains, supporting the competitive advantages of companies in a range of operations from manufacturing to sales. With this viewpoint, the present paper develops an integrated inventory model in which manufacturing is carried out at the vendor’s end so as to fulfill demand at the buyer’s doorway. As the production process is presumed to be imperfect it shifts from an “in-control” state to “out-of-control” state at any random time and yields non-conforming items. The vendor uses regular preventive maintenance actions for the efficient operation of the production system and offers free minimal repair warranty on the products sold to the buyer. Along with preventive maintenance actions the vendor also uses the rework process and restoration process as effective steps towards minimizing the imperfections of the production system. The proposed model solves the non-linear cost minimization problem through a generalized reduced gradient method by using Lingo 15.0. The aim is to jointly optimize the order size, backorder size and the number of shipments in order to minimize the integrated cost of the vendor and the buyer. Numerical analysis and sensitivity analysis is performed on key parameters that render some important supervisory insights.

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EL-FERIK, SAMI, e MOHAMMED BEN-DAYA. "INTEGRATED PRODUCTION MAINTENANCE MODEL UNDER IMPERFECT AGE-BASED MAINTENANCE POLICY AND NON-NEGLIGIBLE MAINTENANCE TIMES". Asia-Pacific Journal of Operational Research 27, n. 04 (agosto 2010): 539–58. http://dx.doi.org/10.1142/s0217595910002843.

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This paper deals with an integrated production maintenance model where preventive maintenance (PM) activities are carried out at the end of each production run or at failure, whichever of them occurs first. PM activities take a fixed amount of time. However, due to the random nature of failures, the stock built during the production period may deplete before the next production run starts, leading to some loss in demand. After N production runs, the process is replaced (or undergoes a major repair), which brings it to the "as-good-as-new" condition. A mathematical model is derived for this problem and a model analysis conducted to characterize optimal solutions. Numerical examples are used to illustrate the proposed model and conduct a sensitivity analysis with respect to key model parameters.

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Fang, Tingchen, Yiming Zhao, Jian Gong, Feiliang Wang e Jian Yang. "Investigation on Maintenance Technology of Large-Scale Public Venues Based on BIM Technology". Sustainability 13, n. 14 (16 luglio 2021): 7937. http://dx.doi.org/10.3390/su13147937.

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Recently, the digital operation and maintenance of large-scale public venues have received increasing attention. The traditional building automation system (BAS), which can only provide information in a non-visualized way, is incapable of meeting the complex requirements of modern operation and maintenance. Therefore, a 3D-based building information modeling (BIM) technology is needed to improve operation and maintenance efficiency. In the paper, a BAS-to-BIM combined strategy is introduced, and the BIM-based maintenance object framework for large-scale public venues is re-built. The conversion method and lightweight method for the BIM maintenance model are introduced and a new type of public protocol, which can be used to attain a unified protocol layer that serves the BIM model, is proposed. In addition, this article presents the application of technologies, such as virtual/mixed reality, to improve the convenience of operation and maintenance. Finally, a practical project of a snow-sports stadium is given as an example to elaborate on the benefit of the proposed method. It indicates that the functions, for example, information integration, visualization, and positioning, introduced by BIM technology can effectively improve the quality and efficiency of project operation and maintenance.

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LIM, JAE-HAK, e DONG HO PARK. "OPTIMAL PERIODIC PREVENTIVE MAINTENANCE SCHEDULES WITH IMPROVEMENT FACTORS DEPENDING ON NUMBER OF PREVENTIVE MAINTENANCES". Asia-Pacific Journal of Operational Research 24, n. 01 (febbraio 2007): 111–24. http://dx.doi.org/10.1142/s0217595907001139.

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This paper considers a periodic preventive maintenance policy under which each preventive maintenance (PM) reduces the hazard rate of the repairable system, while keeping the pattern of hazard rate unchanged. For this model, the hazard rate at a given time t is affected by the improvement factor which depends on the number of PMs conducted until t. In addition to the periodic preventive maintenance, the system undergoes the minimal repair at each failure between the preventive maintenances. We derive mathematical formulas to evaluate the expected cost rate per unit time by computing the expected number of failures depending on the hazard rate of the underlying life distribution of the system. Assuming that the system is replaced by a new one at the N-th preventive maintenance, the optimal values of N and the preventive maintenance period, which minimize the expected cost rate, are solved and thus the best schedules for the periodic preventive maintenance policy are established. Explicit solutions for the optimal schedule for the periodic preventive maintenance are presented when the failure times follow the Weibull distribution.

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Indriartiningtias, Retno, Untung Fadel Ibrahim e Ika Deefi Anna. "Preventive Maintenance Policy to Improve the Effectiveness of XYZ Machine". E3S Web of Conferences 517 (2024): 05025. http://dx.doi.org/10.1051/e3sconf/202451705025.

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PT ABC which is a manufacturing company that produces steel pipes. The last period there was an XYZ machine that often downtime and disrupted the production process. The breakdowns indicate the ineffectiveness of machine. It was necessary to identify and analyze the problems that occurred and the factors that caused the problem. Measurement of machine effectiveness dan it caused is carried out using the OEE method. To avoid the recurrence of machine ineffectiveness, machine maintenance is carried out in a preventive manner according to the spare parts classification (there are 3 classifications of spare parts based on price, namely A under Rp.250,000, B between Rp.250,000 -Rp.500,000 and C above Rp.500,000). The results obtained for the average value of OEE for 1 year is 68%, which shows a value below the ideal OEE standard (85%) and needs to be evaluated. From the calculation of the largest losses value is in the reduce speed losses factor of 67%, it is necessary to minimize the difference in ideal cycle time with actual time (operation time). The best scheduling results is using the preventive maintenance policy method with the schedule of maintenance are: for classification A spare parts the maintenance every 3 months, class B every 5 months, and class C every 6 months.

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Mizutani, Satoshi, e Toshio Nakagawa. "Maintenance Overtime Policy with Cumulative Damage". International Journal of Mathematical, Engineering and Management Sciences 3, n. 2 (1 giugno 2018): 123–35. http://dx.doi.org/10.33889/ijmems.2018.3.2-010.

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We propose an extended maintenance overtime policy for the cumulative damage model where an operating unit suffers some damage due to shocks. It is assumed that the total damage is additive, and the unit fails when the total damage has exceeded a prespecified damage level. It is supposed that we start to observe occurrence of shocks after time T, and the unit is replaced at Nth (N=1,2,…) shock over time T or at failure, whichever occurs first. That is, we propose a new policy by extending maintenance overtime policy. One example is a rental of system such as industrial equipment with some reservations. For such systems, they should be maintained or replaced at a prespecified number of uses over a scheduled time. For such a model, we obtain the mean time to replacement and the expected costs rate. Further, we discuss about optimal number N^* and time T^* which minimizes the expected cost rate when shocks occur in a Poisson process. Finally, numerical examples are given, and suitable discussions are made.

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Qiu, Qingan, Lirong Cui, Jingyuan Shen e Li Yang. "Optimal maintenance policy considering maintenance errors for systems operating under performance-based contracts". Computers & Industrial Engineering 112 (ottobre 2017): 147–55. http://dx.doi.org/10.1016/j.cie.2017.08.025.

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Kreimer, Joseph, e Abraham Mehrez. "An optimal operation policy for real-time n-server stand-by systems involving preventive maintenance". European Journal of Operational Research 69, n. 1 (agosto 1993): 50–54. http://dx.doi.org/10.1016/0377-2217(93)90089-6.

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Wang, Tingsong, Guangxu Gao, Kai Wang e Jia Shi. "Integrated operation models with quay crane maintenance in a container terminal". Ocean & Coastal Management 251 (maggio 2024): 107101. http://dx.doi.org/10.1016/j.ocecoaman.2024.107101.

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Jayakumar, Archana, e Sohrab Asgarpoor. "MAINTENANCE OPTIMIZATION OF EQUIPMENT BY LINEAR PROGRAMMING". Probability in the Engineering and Informational Sciences 20, n. 1 (12 dicembre 2005): 183–93. http://dx.doi.org/10.1017/s0269964806060128.

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Optimal levels of preventive maintenance performed on any system ensures cost-effective and reliable operation of the system. In this paper a component with deterioration and random failure is modeled using Markov processes while incorporating the concept of minor and major preventive maintenance. The optimal mean times to preventive maintenance (both minor and major) of the component is determined by maximizing its availability with respect to mean time to preventive maintenance. Mathematical optimization programs Maple 7 and Lingo 7 are used to find the optimal solution, which is illustrated using a numerical example. Further, an optimal maintenance policy is obtained using Markov Decision Processes (MDPs). Linear Programming (LP) is utilized to implement the MDP problem.

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Zhou, Binghai, e Zilong Liu. "Optimizing preventive maintenance: a deteriorating system with buffers". Industrial Management & Data Systems 116, n. 8 (12 settembre 2016): 1719–40. http://dx.doi.org/10.1108/imds-01-2016-0026.

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Purpose Making decisions on preventive maintenance (PM) policy and buffer sizing, as is often studied, may not result in overall optimization. The purpose of this paper is to propose a joint model that integrates PM and buffer sizing with consideration of quality loss for a degenerating system, which aims to minimize the average operation cost for a finite horizon. The opportunistic maintenance (OM) policy which could increase the output and decrease the cost of the system is also explored. Design/methodology/approach A joint PM and buffer size model considering quality loss is proposed. In this model, the time-based PM and the condition-based PM are taken on the upstream and the downstream machine, respectively. Further, the OM policy based on the theory of constraints (TOC) is also considered. An iterative search algorithm with Monte Carlo is developed to solve the non-linear model. A case study is conducted to illustrate the performance of the proposed PM policies. Findings The superiority of the proposed integrated policies compared with the separate PM policy is demonstrated. Effects of the policies are testified. The advantages of the proposed TOC-based OM policy is highlighted in terms of low-cost and high-output. Originality/value Few studies have been carried out to integrate decisions on PM and buffer size when taking the quality loss into consideration for degenerating systems. Most PM models treat machines equally ignoring the various roles of them. A more comprehensive and integrated model based on TOC is proposed, accompanied by an iterative search algorithm with Monte Carlo for solving it. An OM policy to further improve the performance of system is also presented.

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Bukša, Ante, Ivica Šegulja e Vinko Tomas. "Adjustment of Maintenance Approach for Improved Operability and Safety of Ship Navigation". PROMET - Traffic&Transportation 22, n. 2 (27 gennaio 2012): 95–103. http://dx.doi.org/10.7307/ptt.v22i2.168.

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By adjusting the maintenance approach towards the significant components of ship’s engines and equipment, through the use of operational data from the ship machinery’s daily reports, higher operability and navigation safety can be achieved. The proposed maintenance adjustment model consists of an operation data analysis and risk analysis. The risk analysis comprises the definition of the upper and the lower risk criterion, as well as the definition of a risk index. If the risk index is higher than the lower risk criterion, the component is significant, while it is not significant and has an acceptable risk index if the risk index is lower than the lower risk criterion. For each significant component with a risk index found to be “unacceptable” or “undesirable”, an efficient maintenance policy needs to be adopted. The assessment of the proposed model is based on data regarding the power engine original operation throughout a 13-year period. The results of engine failure examinations reveal that the exhaust valve is the most vulnerable component with the highest rate of failure. For this reason the proposed model of adjusting the maintenance approach has been tested on the exhaust valve sample. It is suggested that the efforts to achieve higher ship operability and navigation safety should go in the direction of periodical adjustments of the maintenance approach i.e. choosing an efficient maintenance policy by reducing the risk indices of the significant engine components. KEY WORDS: maintenance adjustment approach, risk analysis, risk index, lower risk criterion, upper risk criterion, significant components, ship navigation

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Zhao, Bo Ya, Song Yang, Zhe Zhang e Ri Sheng Sun. "Control Improvement of the Reactor Protection System". Applied Mechanics and Materials 71-78 (luglio 2011): 4199–202. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.4199.

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In this paper an optimal maintenance policy for a Reactor Protection System (RPS) for a nuclear plant was developed. RPS consists of continuously operating sub-systems that were subject to random failures. A block system diagram for RPS had been proposed that facilitates analyzing of individual sub-systems separately. The proposed maintenance policy is the Age Replacement model, which incorporated both corrective and preventive maintenances. A Markov model was used to optimize the preventive maintenance interval of those sub-systems whose failure and repair rates were exponentially distributed. Finally, a sensitivity analysis had been performed and recommendations for maintaining the required RPS availability have been suggested.

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Cai, Yiwei, John J. Hasenbein, Erhan Kutanoglu e Melody Liao. "SINGLE-MACHINE MULTIPLE-RECIPE PREDICTIVE MAINTENANCE". Probability in the Engineering and Informational Sciences 27, n. 2 (28 marzo 2013): 209–35. http://dx.doi.org/10.1017/s0269964812000423.

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This paper studies a multiple-recipe predictive maintenance problem with M/G/1 queueing effects. The server degrades according to a discrete-time Markov chain and we assume that the controller knows both the machine status and the current number of jobs in the system. The controller's objective is to minimize total discounted costs or long-run average costs which include preventative and corrective maintenance costs, holdings costs, and possibly production costs. An optimal policy determines both when to perform maintenance and which type of job to process. Since the policy takes into account the machine's degradation status, such control decisions are known as predictive maintenance policies. In the single-recipe case, we prove that the optimal policy is monotone in the machine status, but not in the number of jobs in the system. A similar monotonicity result holds in the two-recipe case. Finally, we provide computational results indicating that significant savings can be realized when implementing a predictive maintenance policies instead of a traditional job-based threshold policy for preventive maintenances.

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PARK, J. H., S. C. LEE, J. W. HONG e C. H. LIE. "AN OPTIMAL BLOCK PREVENTIVE MAINTENANCE POLICY FOR A MULTI-UNIT SYSTEM CONSIDERING IMPERFECT MAINTENANCE". Asia-Pacific Journal of Operational Research 26, n. 06 (dicembre 2009): 831–47. http://dx.doi.org/10.1142/s021759590900250x.

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A block preventive maintenance (PM) policy for a multi-unit system composed of identical units is investigated in this paper. The block PM model of this paper considers periodic inspection and periodic imperfect maintenance. The imperfect maintenance effects are formulated using improvement factor and age reduction model. We define variables of maintenance policy as the inspection period and the PM period and obtain an optimal maintenance policy which minimizes the average total cost. A numerical example is presented, and some sensitivity analyses for model parameters are also investigated.

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Nam, Seong-Nam, Thao Thi Nguyen e Jeill Oh. "Performance Indicators Framework for Assessment of a Sanitary Sewer System Using the Analytic Hierarchy Process (AHP)". Sustainability 11, n. 10 (14 maggio 2019): 2746. http://dx.doi.org/10.3390/su11102746.

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In this study, performance indicators (PIs) for assessing services of the sanitary sewer system in South Korea were evaluated based on general opinions collected from experts in the field. The analytic hierarchy process (AHP) was then carried out. The evaluated set of PIs consisted of five major criteria: management, operation and maintenance, service, environment, and finance. Using the experts’ survey incorporated into the AHP tool, the prioritization of the five criteria was performed, consisting of a total of 14 indicators and 34 checklists on three levels. Of the criteria groups, operation and maintenance was found to be the most important indicator, comprising 43% of all the scores. The AHP results showed that, of the 34 checklists, 13 indicators were explained as candidates of key PIs: on-the-job training and work role and responsibility from management, sewer condition inspection, pump, sewer maintenance, flow rate/water quality/odor monitoring from operation and maintenance, complaint resolution from service, inflow volume from environment, and operational cost in annual expenditures from finance. The PIs developed in this study are expected to be used by stakeholders involved in the provision of sewer services, such as undertaking companies, policy-making bodies, and financing agencies.

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Wari, Ezra, Weihang Zhu e Gino Lim. "A Corrosion Maintenance Model Using Continuous State Partially Observable Markov Decision Process for Oil and Gas Pipelines". Algorithms 16, n. 7 (18 luglio 2023): 345. http://dx.doi.org/10.3390/a16070345.

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This paper proposes a continuous state partially observable Markov decision process (POMDP) model for the corrosion maintenance of oil and gas pipelines. The maintenance operations include complex and extensive activities to detect the corrosion type, determine its severity, predict the deterioration rate, and plan future inspection (monitoring) schemes and maintenance policy. A POMDP model is formulated as a decision-making support tool to effectively handle partially observed corrosion defect levels. It formulates states as the pipeline’s degradation level using a probability distribution. Inline inspection (ILI) methods estimate the latest state of the pipeline, which also defines the initial state of the optimization process. The set of actions comprises corrosion mitigation operations. The errors associated with the ILI method are used to construct the observation function for the model. The sum of inspection, maintenance operations, and failure costs for a given state and action are formulated as rewards. Numerical experiments are made based on data collected from the literature. The results showed that different policies, whether derived from solvers (theoretical) or determined from practical experience, can be compared to identify the best maintenance alternative using the model. It was also observed that the choice of the solvers is important since they affect the discounted rewards and the run time to obtain them. The model approximates the parameters and uncertainty associated with the propagation of corrosion, proficiency of inspection methods, and implementation of maintenance policies. Overall, it can be applied to improve the maintenance decision-making process for the oil and gas pipeline as it incorporates the stochastic features of the operation.

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