• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1288-1290
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• 2003

The maintenance CALS system for car of urban transit is a part of standardization and development of urban transit system, and We have been performed the establishment of maintenance CALS system from 2001 to 2005. The RAMS for management computerization system are utilized in a variety of CALS system for user's convenience and safety in maintenance. Ever since its inception though, the urban transit has searched for ways to improve reliability, availability, maintainability and safety of the railway subsystem. In this paper, This system include RAMS(reliability, availability, maintainability and safety) and expert system of the vehicles shall be enhanced in the future.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1997.10a
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• pp.193-196
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• 1997

In this paper we consider a Bayesian theoretic approach to periodic incomplete preventive maintenance with minimal repair at failure. We assume that the system failure rate is increasing as the frequency of PM increases and that the system is replaced at the K-th PM under this maintenance strategy. The optimal policies which minimize the expected cost rates are discussed. We seek the optimal periodic PM interval x and replacement time K under a Weibull failure intensity. Assuming suitable prior distribution for the Weibull parameters, we derive the posterior distribution incorporating failure data and obtain the updated optimal replacement strategies.

• Journal of Sensor Science and Technology
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• v.25 no.2
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• pp.91-102
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• 2016

The objective of this paper is to propose a heuristic algorithm to optimize the railway track maintenance scheduling, a NP-hard problem, by reflecting conditions of the actual field more quickly and easily. We develop the mechanism based on Binary Artificial Bee Colony (BABC) and Binary Harmony Search (BHS), and verify their performance through simulation experiments. Our proposed BABC and BHS mechanisms were applied to problems composed of 30, 60, 100, and 200 operations for railway track maintenance scheduling to carry out experiments and analysis. On comparing it with the results solved by CPLEX, it is found that the mechanism could present an optimal solution within limited time by user.

• Korean Management Science Review
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• v.24 no.1
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• pp.77-90
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• 2007

Taguchi assumed that a product characteristic has the uniform distribution in its preventive maintenance limit when deriving the expected loss generated by the quality deviation. But it is reasonable to assume that a product characteristic has the normal distribution than the uniform distribution. On this paper, we first find the optimum inspection interval and the optimum preventive maintenance limit under the truncated triangular distribution. Secondly we use the beta-general distribution and compare with the truncated triangular distribution. By using the numerical examples, we find the optimum inspection interval and the optimum preventive maintenance limit under their distributions. As a result, we find that the beta-general distribution gives the best solution and easy calculation.

• Korean Management Science Review
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• v.24 no.2
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• pp.81-93
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• 2007

Achieving a target operational availability is more economical and efficient than having many quantities of the weapon system, since the cost of weapon system becomes expensive. The intent of this study is twofold; first, we develop the simulation model to determine the optimal inventory level of the maintenance float while achieving a target operational availability of the Korean-made helicopter. The quantity decision model considers following factors such as a reliability. a turn around time(TAT). a protection level for inventory, and so on. Second, we analyze whether the existence of a lateral transshipment among bases and the reduction of TAT relate to an inventory level and the operational availability. The research result shows that both TAT and lateral transshipment have an effect on reducing the inventory level of the maintenance float and improving an operational availability.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.326-331
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• 2005

RCM developed by American air industry in early 1960, its process is most realistic for some physical assets and it permits the system to maintain given function status through decision of demand about optimum maintenance. Therefore, many industries have selected RCM technique and have carried out RCM in order to solve many problems concerning maintenance management. Through the execution of RCM, we can solve actual problems And finally we will be able to develop more and more maintenance activities with RCM notion. In this study, we will consider the application of KTX-RCM which is set up with basic theory of RCM and constructed to improve trainset safety, availability and regularity of KTX, linking with CMMS(Computerized Maintenance Management System).

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.10
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• pp.63-73
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• 2018

As the life cycle of buildings is expected to increase, new constructions will decrease and the proportion of remodeling and repair will increase. Therefore, there is an increasing need for overall performance management of old buildings. In 2020, the proportion of buildings over 30 years old is expected to reach a half. As a result, the demand for securing and improving the performance in the stage of using the building is increasing due to the change in the demand for the building, such as the decrease in the construction permit and the increase in the use of the existing building. From this perspective, the study sought to consider institutional measures to organize the preventive and conservative maintenance of buildings. For this purpose, the conceptual goals of inspection for building maintenance were set through a literature review, and the status and problems associated with building maintenance were analyzed to suggest ways to improve the inspection system for building maintenance.

• The Journal of Sustainable Design and Educational Environment Research
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• v.13 no.2
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• pp.13-25
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• 2014

The recent trend has been consistently raised by the media of educational environment issues such as deteriorated existing school facilities, water-leaks due to the lack of proper maintenance and poor toilet facilities. For the efficient use of the budget to be used for maintenance of school facilities, an effort to extend the life of the facility to the max is needed. However, current maintenance system of school facilities is to deal with the defects after discovered, and consequently the durable period is shortened due to early deterioration of facilities and efficient budget execution cannot be realized. For this reason, the result emphasizes the need to improve maintenance management system of school facilities, and proposes a systematic bill of school facilities maintenance according to expert investigation and correlation analysis through school facilities maintenance-related information that is distributed to a number of laws.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.10 no.1
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• pp.37-43
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• 2014

Nuclear power plants(NPPs) are consisted of power production functions and safety functions preventing leakage of radiation. Operators working in NPPs shall maintain these functions during an operation period through various activities such as improvement & modification, corrective maintenance, preventive maintenance and surveillance test. According to the performance of these work activities, there are configuration changes in NPPs systems. Its changes cause the increase of safety risks(CDF) and plant trip risks. Recently, the importance of risk management is increasing gradually in the operation process of NPPs. Therefore, this paper presents the work management methods using the various risk monitoring systems during power operation and overhaul period. Also this paper suggests the optimum application ways of risk systems for work management.

• International Journal of Highway Engineering
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• v.14 no.6
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• pp.13-23
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• 2012

PURPOSES : This study is to improve the highway management and rehabilitation efficiently by method for asset management. METHODS : Based on the literature review, The concept of this paper is to investigate the use of asset values from a Bridge management system to improvement of maintenance system more efficiently. This study is suggested for an evaluation method based on the current bridge condition by Written-down replacement cost of the assets. RESULTS : We suggests the optimization methodology of road asset valuation for budge distribution and performance measure. CONCLUSIONS : We evaluate all of national highway's bridge by the optimization methodology of road asset valuation, and suggest application methods of asset result.