• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.2
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• pp.171-178
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• 2009

Logistic support activities for weapon systems play an important role at maintenance activities in modern warfares. These activities are essential for keeping weapon systems ready at all time. However, maintenance supplies can be delayed without a proper information system. Further, increases of mean time to repair (MTTR) and unavailability of weapon systems can be occurred. In this study, a web based information system is developed for logistic chains of class 9 supplies. Utilizing web database technologies, the developed system can provide an environment for data exchange and sharing among various participants in the supply chain.

• Journal of the Korean Society of Safety
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• v.16 no.4
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• pp.213-217
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• 2001

Requirements for Device Networks differ greatly from those of typical data networks. Specifically, any device network technology which employs a fieldbus protocol is different from IP network protocol TCP/IP. In general, one needs to integrate fieldbus protocol and TCP/IP to realize device network over IP network or internet. Interoperability between devices and equipments is essential to enhance the quality and the performance of predictive maintenance(PM). This paper suggests a basic framework for web-based predicted maintenance and a method to guarantee interoperability between devices and equipments.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.481-486
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• 2008

The building HVAC systems have very different qualities of performance and durability with the superintendent's ability for management and maintenance. The poor management of these systems finally lead to the shortening of the life expectancy and result in the increase of operating costs and energy consumptions due to low efficiencies. So it is essential to try to develop ways to adequately maintain and to use the building facilities efficiently in order to preserve earth environment and the limited resource. In this study, the LCC based numerical calculation package will be developed for the efficient maintenance plan and the determination of the reasonable time of repair or replacement of equipments.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.235-240
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• 2008

Since urban railway transit is one of the most essential transportation systems, its power facilities must ensure high reliability and safety. Currently, urban railway operating organizations perform TBM (Time Based Maintenance) on power facilities. However, in order to improve management efficiency and system safety, CBM (Condition Based Maintenance) is preferred. Among various power facilities, mold transformers has been chosen as the object of study since it is widely used for the purpose of minimizing volume and weight, and due to safety against fire. In this paper, various transformer failure cases due to electric, thermal, mechanical and environmental factors have been collected and analyzed. In addition, investigation on national and international condition based maintenance cases and the characteristics of sensors widely used for transformer monitoring has been performed to suggest the optimal condition based maintenance technique for urban railway systems.

• Korean journal of aerospace and environmental medicine
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• v.30 no.3
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• pp.91-94
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• 2020

The coronavirus infectious disease-19 (COVID-19) pandemic has had a profound impact on the aviation industry. In order to overcome this crisis, airlines have made their efforts in various fields. Therefore, we tried to summarize these efforts of airlines. It is also essential to keep aircraft that have been in landing for a long time in optimal condition. In this paper, we tried to find out about efforts to maintain landing aircraft and maintenance of personnel. Through such constant care, airlines will be able to quickly respond to increasing aviation demand when the infectious disease situation is stabilized in the future. Finally, airlines and passengers must make several efforts to ensure that passengers are free from COVID-19 while traveling by air. These include general precautions to prevent infection, separation of airline personnel and passengers, changes in seat assignments and in-flight services, periodic aircraft disinfection, and prevention of in-flight infections.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.810-819
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• 2007

Usually the status of a bridge is determined by its structural capability and material strength. Consequently a lot of researchers have studied the failure, the fatigue, and the deterioration of the structure in terms of the structural function of a bridge. However, the overall performance of a bridge may be affected simply by the damage of one of its components. Therefore this study utilized a systematic classification and statistical analysis based on the existing bridge inspection data collected in Taiwan to reach the following goals: (1) assess the performance distribution and deterioration rate for bearing and expansion joint of bridge; (2) find out the right time to do the preventive and essential maintenance for the component of bridge with an empirical method, and to decide what time and which component of a bridge will receive preventive maintenance or regular maintenance.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.606-610
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• 1997

울진 원전 3,4 호기 확률론적 안전성 평가 (PSA) 모델을 risk monitor 모델로 변환하여 한국원자력연구소에서 개발한 risk monitor인 Risk Monster[1]에 설치하였으며 이를 이용하여 필수냉각수 계통(ESW;Essential Service Water) 펌프의 가동중 정비(on-line maintenance)의 가능성 여부를 연구하였다. ESW 펌프를 가동중 정비하더라도 안전성 측면에서 별 문제가 없으며 경제성 여부는 보다 정확한 검토가 요구되나 상당히 있는 것으로 판단된다. 한편 ESW펌프 한대의 고장이 원전 가동중에 미치는 위험도를 분석하였으며 그 결과 ESW펌프 한대의 고장에도 불구하고 원전 계속 가동에는 큰 문제가 없었다.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.150.3-150
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• 2001

Requirements for Distributed Monitoring and Control Networks (DMCN) differ greatly from those of typical data networks. Specifically, any DMCN technology which employs a fieldbus protocol is different from If network protocol TCP/IP. In general, one needs to integrate fieldbus protocol and TCP/IP to realize DMCN over IP network or internet Interoperability between devices and equipments is essential to enhance the quality and the performance of predictive maintenance (PM). This paper suggests a basic framework for LonWorks-based DMCN over IP network and a method to guarantee interoperability between devices and equipments.

• The Journal of the Korean dental association
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• v.55 no.1
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• pp.90-95
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• 2017

As residual ridge resorption occurs, complete dentures tend to become loose. Denture relining and rebasing are an essential element for improving a denture's stability and prevention side effect such as sore spot, epulis fissuratum. This paper focuses about health insurance is available for maintenance of complete denture and, methods of relining or rebasing.

• Journal of Electrical Engineering and Technology
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• v.6 no.4
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• pp.431-438
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• 2011

To ensure that equipment outages do not directly impact the reliability of the ISO-controlled grid, market participants request permission and receive approval for planned outages from the independent system operator (ISO) in competitive electricity markets. In the face of major generation outages, the ISO will make a critical decision as regards the scheduling of the essential maintenance for myriads of generating units over a fixed planning horizon in accordance with security and adequacy assessments. Mainly, we are concerned with a fundamental framework for ISO's maintenance coordination in order to determine precedence of conflicting outages. Simulated annealing, a powerful, general-purpose optimization methodology suitable for real combinatorial search problems, is used. Generally, the ISO will put forward its best effort to adjust individual generator maintenance schedules according to the time preferences of each power generator (GENCO) by taking advantage of several factors such as installed capacity and relative weightings assigned to the GENCOs. Thus, computer testing on a four-GENCO model is conducted to demonstrate the effectiveness of the proposed method and the applicability of the solution scheme to large-scale maintenance scheduling coordination problems.