• Proceedings of the Korean Reliability Society Conference
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• 2000.11a
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• pp.335-342
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• 2000

Preventive maintenance(PM) is an action taken on a repairable system while it is still operating, which needs to be carried out in order to keep the system at the desired level of successful operation. The PM improves the reliability of the system by predicting the possible failures and thereby preventing such failures from its occurrence. In this paper, we develop the optimal preventive maintenance policies based on the aperiodic PM model. We investigate an aperiodic preventive maintenance policy and propose several optimal PM policies which minimize the expected cost over an infinite time span. Park, Jung and Yum(2000) determine the optimal period and the optimal number of PMs based on Canfield's(1986) periodic model. Our techniques to derive the optimal preventive maintenance policies based on our aperiodic PM model is similar to those in Park, Jung and Yum(2000), which can be considered as the special case of our results.

• Journal of Korean Society of Rural Planning
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• v.12 no.1 s.30
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• pp.11-21
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• 2006

The purpose of this study is to verify the result of the previous studies and to clarify the types and activation factors of maintenance activities of the naturally favorable water space through the participation of residents in rural areas, through a further survey of the area proposed as a program in the existing study review and previous study related to the participation of residents. The survey was conducted through the survey of 1,242 households and 1,335 persons intended for Japanese rural areas. The study result is summarized as follows. The types of the maintenance activities in the areas intended for the survey have been classified into 'rural type' and 'combination type' through the analysis results by the references like the comparison analysis, job percentage and main utilization purpose of facilities for each type of maintenance and operation activities. In case of the 'rural type' area, residents were doing maintenance activities centered on the group activities rather than personal maintenance activities. Also, the activities of maintenance & operation group members were more active than non-members, and the water-friendly utilization to the facilities was not directly affecting the maintenance activities of residents. In case of the 'combinational type' area, there was no common characteristic according to each area, and the participation percentage in the maintenance activities was low compared with the 'rural type' area. According to the analysis result based on the participation degree of personal maintenance activities, the repair of facilities as a naturally favorable water space, implementation of projects reflecting the opinions of residents, educational programs conducted in order to motivate the participation of residents, etc. have been analyzed as the factors affecting the activation of maintenance activities of residents. Through the above results, for continuous maintenance activities to be made with residents as a main body in the future, it is necessary to support maintenance groups on an administrative level and procure experts for the production and operation of programs that can increase the participation percentage of residents.

• Journal of Korean Society of Archives and Records Management
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• v.22 no.2
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• pp.135-154
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• 2022

Through this study, the following proposals were made to secure the operability of local governments' records management systems (RMSs). First, for the stable operation and maintenance of RMS, establishing a noninterruptible system with regular operation support is necessary. Second, improving the maintenance quality above a certain level by establishing an integrated RMS maintenance system is imperative. Third, systematically managing the RMS infrastructure compatibility list should be vital to provide clear standards for maintaining local governments' RMS structure.

• Journal of the Korea Society for Simulation
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• v.30 no.1
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• pp.65-73
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• 2021

The maintenance of the guided missiles typically requires the efficient management of spare parts and maintenance time. This study analyzed the impact of the maintenance time on operational availability. This study classifies the maintenance team with consideration of the skill level of the Harpoon guided missile maintenance and the goal is to analyze the impact on the operational availability with the skill levels quantitatively. Based on the real maintenance data of Harpoon guided missiles, a simulation model is constructed and analyzed. The analysis of the simulation result shows the trade-off between the maintenance time and operational availability. It is expected that the simulation model can help the maintenance policies of guided missiles.

• Journal of Energy Engineering
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• v.20 no.2
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• pp.154-162
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• 2011

PMT(Preventive Maintenance Template) is a standardized maintenance program that describes maintenance items & period as operation condition to increase component reliability at the component level. The existing maintenance programs are focused on time based maintenance to inspect and repair component depend on fixed period. But recently, we have developed advanced maintenance program(named PMT) to increase reliability and optimize maintenance program of the plant significant component. This paper presents how to develop the PMT for nuclear power plant's static exciter.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.3
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• pp.147-154
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• 2023

In the case of river facilities, the management of this information differs depending on national and regional rivers, therefore, there is no integrated management in place. There is concern about the loss of facility information owing to the insufficient accumulation of information during their design and construction stages. Additionally, as a result, the utilization level of facility information during the maintenance and operation stages is insufficient. To ensure effective maintenance and operation of river facilities, it is necessary to secure data consistency and increase efficiency by organizing facility information according to a standardized classification system. This study proposes a strategy for implementing the BIM standard classification system in the river sector, considering facility characteristics. The goal is to introduce a BIM information model for 3D-based river facilities, and enable efficient maintenance and operation conversion.

• Journal of Information Technology Services
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• v.21 no.3
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• pp.43-61
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• 2022

With the development of information technology, IT-based services in public administration has become more indispensable. As a result, the importance of IT maintenance projects to improve the efficiency of IT services and secure service levels is growing. Due to the nature of IT maintenance projects on local government, which mainly involve small and medium-sized IT companies in the region, business participating companies often do not have an appropriate methodology for service quality management. To solve this situation, the government has prepared a service level agreements (SLAs) that can be applied to IT maintenance projects. However, most local governments do not use SLAs for IT maintenance projects. As a result, various problems such as failure of the IT maintenance project or deterioration of quality are occurring Thus, this paper suggested major indexes to evaluate which service factors affect the efficient operation of information systems and the improvement of service quality in IT maintenance projects of local governments and analyzed the importance of indexes based on AHP method. Using this research method, this study found the theoretical implications on the outsourcing service of IT maintenance.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.6
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• pp.1901-1910
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• 2014

Current domestic and overseas BIM practice and research efforts show very few examples that design and construction BIM data could be successfully used for efficient operation and maintenance (O&M) of infrastructure in particular. This study takes public wastewater treatment plant requiring an enhancement of operation and maintenance capability into account to develop a prototype BIM-based maintenance management system. The system is designed and implemented following a typical system development procedure and validated by the system outputs per four scenarios being considered to be main maintenance activities: The research results are expected to contribute to the upgrade of current wastewater treatment plant maintenance level, which is more demanded as water-related regulation and policy direction changes to region-based large scale O&M and asset management adoption, and overseas market participation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.9
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• pp.1507-1513
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• 2010

The $CO_2$ emission can be decreased due to freedom of generator maintenance scheduling(GMS). This paper proposes assessment of $CO_2$ emission considering generator maintenance scheduling(GMS) and evaluates effect of the GMS on $CO_2$ emission. And also, this paper assesses the $CO_2$ emission and the probabilistic production cost simulation of nuclear and thermal power generators considering operation of hydro and pumped generator. The minimum reliability criterion level satisfied production cost minimization function model is used in this paper. The practicality and effectiveness of the proposed approach are demonstrated by simulation studies for a real size power system in Korea in 2010.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.2
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• pp.103-111
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• 2015

In general, no particularly well-established standards have been in place so far, for the method of evaluating the deteriorated level of pipes and ducts of industrial facilities. For that reason, the evaluation depends upon various studies which are based on the analysis of the residual life, thickness thinning, closure rate, and scale thickness that measure a few specific positions of pipes. It also depends upon the expertise in business operation and the specific techniques conducted by the inspection companies and institutions. This research introduces the concept of measuring units per section and the selection method of measurement points per section. Furthermore, specific methodologies were developed to plan and analyze deterioration level of industrial pipes and ducts by engineers and managers using a section map. Consequently, applying the outcomes from this study to the plant equipment of the incineration facility resulted in saving 42% of the repairing and remodeling cost.