• Journal of the Korea Safety Management & Science
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• v.7 no.1
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• pp.101-115
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• 2005

This study deals with the procedure of safety improvement, productivity increase ,and tact-time reduction through setting up the system about preventive maintenance. Actually, it is hard to establish and carry out preventive maintenance, even though we recognize the importance of the system concerning time, cost, labor, and so forth. In this study in the viewpoint of cost we are for achieving maximum efficiency by change and reduction of planning process adapted to the special work group. At first we briefly will mention the kind ,the necessity ,and the concept of preventive maintenance ,and then divide the equipment used in the assembly line into the two whether it is necessary or not by way of estimating the breakdown loss ,comparing with general establishment of preventive maintenance and modifying it to the case. At the second step we will establish the operation system of plan management related to production and quality in the special case. Check period and category will be set by dividing the assembly equipment into LCL and Focus in the third step. The forth step will contain the operation procedure in detail. And then we must make check and repair record periodically. Finally, on the basis of the record the selection of checking of significance will be conducted. This results in safety improvement, tact time reduction, and productivity improvement.

• Proceedings of the Safety Management and Science Conference
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• 2004.11a
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• pp.131-141
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• 2004

This study deals with the procedure of safety improvement, productivity increase, and tact-time reduction through setting up the system about preventive maintenance. Actually, it is hard to establish and carry out preventive maintenance, even though we recognize the importance of the system concerning time, cost, labor, and so forth. In this study in the viewpoint of cost we are for achieving maximum efficiency by change and reduction of planning process adapted to the special work group. At first we briefly will mention the kind, the necessity, and the concept of preventive maintenance, and then divide the equipment used in the assembly line into the two whether it is necessary or not by way of estimating the breakdown loss, comparing with general establishment of preventive maintenance and modifying it to the case. At the second step we will establish the operation system of plan management related to production and quality in the special case. Check period and category will be set by dividing the assembly equipment into LCL and Focus in the third step. The forth step will contain the operation procedure in detail. And then we must make check and repair record periodically. Finally, on the basis of the record the selection of checking of significance will be conducted. This results in safety improvement, tact time reduction, and productivity improvement.

• Industrial Engineering and Management Systems
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• v.7 no.1
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• pp.51-56
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• 2008

With growing demand for zero defects, predicting reliability of software systems is gaining importance. Software reliability models are used to estimate the reliability or the number of latent defects in a software product. Most reliability models to estimate the reliability of software in the literature are based on the development lifecycle stages. However, in the maintenance phase, the software needs to be corrected for errors and to be enhanced for the requests from users. These decrease the reliability of software. Software Reliability Growth Models (SRGMs) have been applied successfully to model software reliability in development phase. The software reliability in maintenance phase exhibits many types of systematic or irregular behaviors. These may include cyclic behavior as well as long-term evolutionary trends. The cyclic behavior may involve multiple periodicities and may be asymmetric in nature. In this paper, SGRM has been adapted to develop a reliability prediction model for the software in maintenance phase. The model is established using maintenance data from a commercial shop floor control system. The model is accepted to be used for resource planning and assuring the quality of the maintenance work to the user.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.856-863
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• 2009

The problem of urban decay in Hong Kong has drawn much attention of both practitioners and academics. Poorly managed buildings not just give a negative image to the Pearl of the Orient in the region, but also pose potential risk hazards to the health and safety of the general public. While it is necessary to devise a comprehensive plan on redevelopment and urban planning, preserving the existing buildings to maintain their conditions for habitation can be a short-term option to safeguard quality standard. With the increasing number of ageing buildings in Hong Kong, a lot of research efforts have been devoted to managing repair and maintenance projects properly (for example those initiated and funded by the Construction Industry Institute, Hong Kong; and the current study financially supported by The Hong Kong Polytechnic University). Given the short duration and more diversified nature of work, building repair and maintenance works are found to be more difficult to monitor and regulate when compared with new works. This paper aims to provide a comprehensive analysis on the problems of running building maintenance projects. An extensive review of contemporary literature was firstly conducted, which forms a solid basis for developing an empirical study on the problems and difficulties of running building maintenance projects from the viewpoints of industrial practitioners with a view to formulating effective strategies for managing maintenance projects successfully.

• Proceedings of the Korean Nuclear Society Conference
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• 2001.05a
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• pp.124.2-124
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• 2001

• Journal of Korean Society on Water Environment
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• v.36 no.1
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• pp.29-35
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• 2020

To manage the non-point source pollution and restore the water circulation, many technologies including infiltration or reservoir systems were installed in the urban area. These facilities have many problems regarding maintenance as their operation period becomes lengthier. The purpose of this study was to estimate the optimal maintenance timing through a long-term load test on the infiltration trench as one of the low impact development techniques. An infiltration trench was installed in the demonstration test facility, and stormwater was manufactured by Manual on installation and operation of non-point pollution management facilities from the Ministry of Environment, Korea and entered into the infiltration trench. Particle size distribution (PSD), suspended solids (SS) removal efficiency, and infiltration rate change tests were performed on inflow and outflow water. In case of the PSD, the maximum particulate size in the outflow decreased from 64 ㎛ to 33 ㎛ as the operating duration elapsed. The SS removal efficiency improved from 97 % to 99 %. The infiltration rate changed from 0.113 L/sec to 0.015 L/sec during the operation duration. The maintenance timing was determined based on the stormwater runoff requirements with these changes in water quality and infiltration rate. The methodologies in this study could be used to estimate the timing of maintenance of other low impact development techniques.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.03a
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• pp.284-293
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• 2002

Using the life cycle cost concept, optimum maintenance and retrofit planning for reliable seismic performance is suggested the overall life cycle cost to be minimized including the initial cost, the costs of inspection, repair, and failure. Limit states of the bridges are defined. And failure probabilities are computed through crossing theory. The effect of maintenance and retrofit is represented using the probability of damage detection and event tree analysis. Optimization of maintenance and retrofit planning method proposed from this research was applied to numerical examples. The analysis incorporates the acceleration and site conditions prescribed in the code, and the quality of inspection methods.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.114-116
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• 2005

This paper presents a maintenance application for power transformer. High quality maintenance and accurate diagnosis are essential for all transformers, especially for older ones. The developed application provides maintenance guides for dry type transformer and oil-filled transformer to prevent any malfunctions and to lengthen the lifetime of transformers. Based on windows application, TTS (text to speech) and 3D graphics technologies have been used to enhance the user friendly interface. Developed application is helpful for both expert and novice operators at substation.

• Proceedings of the KSR Conference
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• 2003.10b
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• pp.585-590
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• 2003

The execution with respect to tunnel structure has been carried out more important than maintenance until present time. There is a lot of interests on the maintenance of institution that is used by the nation, because of the recent miserable accidents. Consequently there need an organizational and efficient system. This paper has presented the sort, source and part of damage of tunnel structures etc. and then performed to analyze about the special quality of tunnel structure through input detailed safety assessment report data as well as fulfilment statical analysis. In conclusion, the paper's intention is presenting the maintenance system base on those.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1033-1037
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• 2010

Railway signal facilities are very important because they are directly related to safe train operation. By the result of the unification of signal and station control, station control staffs have been having a hard time to grasp the knowledge about signal facilities and the fault restoration ability in a short term since the existing manuals were only made with text materials. To meet the growing demand to educate the maintenance work in actual and effective way, the maintenance manuals and periodic procedures was developed in the forms of video clips and animations with quality contents onto a DVD enabling not only to improve the maintenance works for signal facilities but to contribute budget saving and profit generating.