• Journal of the Korean Data and Information Science Society
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• v.22 no.4
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• pp.775-784
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• 2011

In this paper, we consider the periodic preventive maintenance model for repairable system following the expiration of non-renewing free replacement-repair warranty (NFRRW). Under this preventive maintenance model, we derive the expressions for the expected cycle length, the expected total cost and the expected cost rate per unit time. Also, we determine the optimal preventive maintenance period and the optimal preventive maintenance number by minimizing the expected cost rate per unit time. Finally, the optimal periodic preventive maintenance policy is given for Weibull distribution case.

• 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.

• Journal of the Korean Institute of Educational Facilities
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• v.26 no.6
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• pp.29-37
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• 2019

The research institute has a function to get the research outcome through the various experiments, data collection and analysis. Therefore, research building is important to keep the research condition or experiment environment. But buildings would be deteriorated and leaded into the deterrence of research. Maintenance is planned to protect the research building condition through various general repair or heavy repair. The heavy repair is generally conducted in massive repair scope or main components preparation. In this paper, it aimed at analyzing the effect of the massive or main components repair with inputted cost and its resulted output. In order to analyze the effect of a massive repair, it used the Benefit/Cost analysis and sensitivity analysis. Results of this study are as follows : The benefit/cost analysis shows that research building whose researcher continuously live and study has good effect. On the contrary, pace of the the experimental function is not good effect in benefit/cost analysis. But the experimental function is indispensible to get the research outcom for the research goal. Therefore, the experimental function will be planned to repair and get the historical repair data because the proper repair time would be prepared to cut down the repair cost.

• Journal of Applied Reliability
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• v.11 no.2
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• pp.167-176
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• 2011

This paper introduces models for preventive maintenance policies and considers periodic preventive maintenance policy with minimal repair when the failure of system occurs. It is assumed that minimal repairs do not change the failure rate of the system. The failure rate under prevention maintenance received an effect by a previously prevention maintenance and the slope of failure rate increases the model where it considered. Also the start point of failure rate under prevention maintenance considers the degradation of system and that it increases quotient, it assumed. Per unit time it bought an expectation cost from under this prevention maintenance policy. We obtain the optimal periodic time and the number for the periodic preventive maintenance by using Nakagawa's Algorithm, which minimizes the expected cost per unit time.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.11
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• pp.3200-3206
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• 2009

This paper describes the problem of existing maintenance system for mail sorting machnies, and presents to-be considerations of maintenance system based on AHP (Analytic Hierarchy Process) analysis with efficiency and economic aspects. There are standard procedure for diagnosis and repair of mail sorting machine as preventive and operational maintenance, roles and missions of maintenance technical support center for upgrade of maintenance skill in this paper. The proposed maintenance system will be adapted for more safety and efficiency maintenance of mail sorting machine.

• Smart Structures and Systems
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• v.15 no.4
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• pp.949-961
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• 2015

The goal of this study is to present numerical modeling and analytical testing in order to evaluate an innovative space truss typed temporary structure, which is used to maintenance and repair of road tunnels. The present space truss structure has merits to use UL-700 high strength steel tube as members and to carry out maintenance and repair works of road tunnels without blocking cars and transportations. Numerical modeling and analytical testing of the space truss are investigated by using commercial engineering software, i.e., ABAQUS 6.5-1, and then it is verified that the truss structure has both structural safety and effective function for maintenances and repairs of road tunnels.

• Proceedings of the Korean Geotechical Society Conference
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• 1998.10a
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• pp.257-266
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• 1998

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1983.10a
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• pp.118-123
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• 1983

A minicomputer system with the purpose of automations the operations of a Repair Service Bureau is described. SLMOS automates three major functional areas-administration, testing, and report senerations In the administration of repair sevice SLMOS performs a database maintenance functions alons with trouble collection and tracking. Trough ALT, automated testing of customer lines is performed, and the results of the test are utilized to dertermine the action taken to effect a repair. Certain problem areas may be detected and corrected by using the reports senerated by Trouble Report statics and Analysis System.

• KIEAE Journal
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• v.12 no.5
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• pp.29-34
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• 2012

A rental housing has a key role to supply the living space to non-ownership. A public rental housing is particularly aimed at providing the living space for the low-income households with a low rent fee. Therefore, the local government would try to maintain the facilities of the rental housing and to get the decent living condition. For getting the required living condition, it should make a maintenance plan, which contains the repair time, repair scope and targeted component and finishings. This study is aimed at providing the optimal repair time in 12 components and components of the rental housing which is controlled by the local government. The optimal repair time has two steps to get the final result. First, it would draw the 1'st repair time with the probabilistic and empirical approach. Second, comparing the drawn data and the service life, the optima repair time would be provided with considering the components' attributes. Result are as follows : First, the optimal repair time would be considered with the component attributes. There are user's convenience, its safety and physical aspect. Second, the kitchen utensils, elevator and water tap has a optimal time of 16, 19, 17 years respectively which is considered with physical aspect. In addition, the optima repair time of the wiring appliance and lighting equipment are 12 years and 10 years respectively.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.1
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• pp.223-230
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• 2006

In this paper the method for repair LCC evaluation of reinforced concrete structures deteriorated by chloride attack was constructed. Also, the FEM analysis for chloride ion penetration into concrete was conducted to evaluate the repair LCC which was decided by the number of repair times including early stages of construction and repair construction during the service life of structures. As a result, the number of repair times is obtained from the comparing the concentration of the chloride ion in a rebar position, and the critical chloride ion concentration of rebar corrosion through the FEM analysis considering the kind of repair materials and methods. Also, the repair LCC could be calculated by the number of repair times during the service life of structures.