• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.36
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• pp.287-295
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• 1995

This paper is concerned with cost analysis model in periodic maintenance policy. Generally periodic maintenance policy in which item is repaired periodic interval times. And in the article minimal repair is considered. Mimimal repair means that if a unit fails, unit is instantaneously restored to same hazard rate curve as before failure. In the paper periodic maintenance policy with minimal repair is as follows; Operating unit is periodically replaced in periodic maintenance time, if a failure occurs between minimal repair and periodic maintenance time, unit is replaced by a new item until tile periodic maintenance time comes. Also unit undergoes minimal repair at failures in minimal-repair-for-failure interval. Then total expected cost per unit time is calculated according to scale parameter of failure distribution. Maintenance cost factors are included operating, fixed, minimal repair, periodic maintenance and new item replacement cost. Numerical example is shown in which failure time of system has weibull distribution.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.143-144
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• 2013

Unit module system produce units in the factory and assemble in the field. This unit module system has advantages of shortening the process of construction. However, it is still in the early research related to setting the unit module which is transported by truck to the field. Therefore, when transporting the unit module, this goal of study develops fixed devices. And suggesting device were performed that simulations analyzed maximum stress and assessed the safety.

• Proceedings of the KIEE Conference
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• summer
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• pp.394-396
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• 2004

In order to reduce the sheath circulating current, same arrangement and balanced length of cable are required for the underground cable system. But practically, changing the whole arrange of cable which is already constructed is impossible. Therefore, It is necessary to apply the restraining-unit of sheath circulating current at the cross-bonding wire of insulated joint because the impedance of restraining-unit is able to reduce sheath circulating current at a normal condition. Even at a transient state, the restraining-unit must maintain electrical and mechanical characteristics. In this paper, the features of restraining-unit developed by LG Cable as well as the electrical test results are described. It proves that the restraining-unit is applicable to the underground cable system where sheath circulating current rises.

• Solar Energy
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• v.18 no.4
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• pp.11-22
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• 1998

Floor panel heating system using hot water is the primary heating system of domestic residential building. This paper presents the results of performance analysis of the heat pump system with air source evaporator and single unit dual sink(SUDSk) condenser. The heat exchanger combines two separated condensers into a single condenser and the object of the SUDSk condenser is to release energy to dual sinks, i.e. air for air heating system and water for panel heating system in one single unit. Simulation program is developed for single unit dual source(SUDS) SUDSk heat pump system and some experimental data are obtained and compared with simulation results. Differences of heating capacity and COP in dual source operating mode are 7% and 8% respectively. Simulation results are in good agreement with test results. Therefore, developed program is effectively used for design and performance prediction of dual source dual sink heat pump system with SUDS evaporator and SUDSk condenser.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.10
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• pp.1005-1013
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• 2009

In this paper, the performance improvement of a decentralized brake system for railway rolling stocks is investigated. In order to verify the effectiveness of the decentralized brake system, it is compared to the truck unit brake system which has only one control unit per a truck. The adaptive sliding mode control scheme is used to realize a robust anti-slip brake control system. Through computer simulations, it is verified that the decentralized brake system has better braking performance than the truck unit brake system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.203-206
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• 2001

This paper presents a straightness measurement system for flat and long workpieces. The measurement system consists of a laser optical unit, a CCD camera and processing system, and a carrier system with a stylus. The carrier system accompanies the stylus, which displaces a retroreflector along the surface profile. The optical unit is used to optically amplify the displacement of retroreflector. The CCD camera and processing system finally identifies the vertical displacement of the stylus unit. The developed system is applied to two surfaces: ground surface and LM guide surface. The experimental results show that the developed system can measure the straightness of flat surfaces within sub-micron error.

• Pallet News
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• s.78
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• pp.3-15
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• 2015

본 원고는 지난 2015년 6월 25일 중국 상하이에서 열린 제 10차 아시아파렛트시스템연맹(APSF) 정기총회 발표 원고로 서병륜 회장(APSF명예회장, KPCA회장, LogisALL그룹 회장)이 '새로운 Unit Load System의 꿈' 이라는 주제로 발표 하였습니다.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.373.4-373
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• 2001

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.728-728
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• 2006

• Journal of the Korean Society for Precision Engineering
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• v.19 no.10
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• pp.7-14
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• 2002