• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.147-148
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• 2006

Recently, due to increasing the application of power electronic equipment, harmonics generated from the non-liner load are fairly produced. Harmonics can cause a variety of problems such as the overheating of distribution transformer, the breakdown of device and communication interference. Interest about power quality decline of power system is very increased. In this paper, we are measured the harmonic voltage and current o( power system to analyze harmonic characteristics, and it is analyzed Total Harmonic Distortion(THD). Also, we Ere modeled power system using PSCAD/EMTDC. And it is analyzed harmonic voltage and current in steady-state. The study results have been indicated the utility about harmonics analysis and modelling for power system.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 압출 및 인발 심포지엄
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• pp.79-82
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• 1999

This paper presents a study of cold combined forward-backward extrusion product. The case of product with thin wall in piercing process occur defects of deformation and breakdown during piercing process and the center web of product with thin thickness cause flow defect. Such defect is made by the difference of material flow. Methods of the material flow control in the two directions and forming process to remove this flow defect is proposed. The effectiveness of the proposed methods is examined by comparison experiment and finite element simulation.

• 한국융합학회논문지
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• 제3권1호
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• pp.7-11
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• 2012

지능형 자동차의 최종 목표는 사고 위험이 전혀 없는 무인 자동차이다. 지능형 자동차의 구현을 위해서는 무선 네트워크 데이터 통신 기술이 중요하다. 본 논문에서는 데이터 통신 기술이 구현이 되었을 때를 가정하여 네트워크 침입 기술에 대해 알아보고, 사용자 인증 및 데이터 위 변조시 그에 따른 보안 취약점과 그에 따른 대응기법을 생체인식 알고리즘 통해 적용하고자 한다. 확실한 사용자 인증 기법과 데이터 전송 기술에 대한 암호화를 통해 더욱 더 안전한 대응 기법을 제안하고자 한다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.1155-1158
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• 2003

In this paper, we studied on the electrical characteristics of insulation material of elastomer epoxy. As the results of test, properties of epoxy represent differently according to elastomer contents. Also, its permittivity, tan ${\delta}$ and BDV(Break-Down Voltage) strength show big difference when those compare before moisture absorption test and after moisture absorption test. From this test we find results that mush elastomer contents can cause insulation properties to degrade.

• 전기학회논문지
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• 제64권1호
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• pp.196-200
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• 2015

The switching noise in the power electronics of the power conversion equipment (Power Conditioning System) for large energy storage devices are generated. Since the burst-level transient noise from being generated in the power system at a higher power change process influences the control circuit of the low voltage driver circuit. Noise may cause the malfunction of the control device even if no dielectric breakdown leads to a control circuit. To overcome this, this paper proposes the installation of an additional nano-surge protection device on the power supply DC output circuit of the battery management unit.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.974-979
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• 2007

From '1994 Gwacheon accident of the Electric Multiple Unit(EMU)' till '2004 Seoul subway 2 lines Guui station accident', the accident is increasing at day and the service demand of the citizen is coming to be various. But it does not deal with technical or operation side demands. There is a possibility of saying that the accident of the EMU or deficit operation is caused by the RCM. The EMU where the efficiency is good though does the time passes and it becomes old anger and does not display that efficiency not only the cause of formation accident does becomes. The breakdown about under occurring before getting up an accident, appropriately shifting the parts is to a maintenance very the pending question fact which is important is a possibility of doing. From there is by an EMU, RCM in reliability base grudge is a tool of confirms an improvement point and the place where it judges. From the research which it sees will present about technical development plan of RCM.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1993년도 제18회 학술대회 초록집
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• pp.77-84
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• 1993

Systems with journal bearings generally operate in large scale and under severe loading conditions such as steam generator turbines and internal combustion engines, in contrast to the machineries using rolling element bearings. Failure of the bearings in these machineries can result in the system breakdown. To avoid the time consuming repair and considerable economic loss, the detection of incipient failure in journal bearings becomes very important. In this experimental approach, acoustic emission monitoring is employed to the detection of incipient failure caused by intervention of foreign particles most probable in the journal bearing systems. It has been known that the intervention of foreign materials, insufficient lubrication and misassembly etc. are principal factors to cause bearing failure and distress. The experiment was conducted under such designed conditions as inserting alumina particles to the lubrication layer in the simulated journal bearing system. The results showed that acoustic emission could be an effective tool to detect the incipient failure in journal bearings.

• 산업공학
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• 제18권3호
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• pp.308-316
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• 2005

Delayed repair to the failure of weapon system can cause enormous damages to military operation. Various materials like diagnostic equipment, general and special tools, technical manuals(maintenance manual and illustrated parts breakdown) and drawing documents are required for maintenance. For existing weapon systems the distributed environment of these various materials reduces the maintenance effectiveness of maintenance crew. In this paper, to provide the information of maintenance procedures and supply to the maintenance crew we develope a digital interactive electronic technical manual of the technical documents which can be used easily in computer through question and answer method and improve maintenance effectiveness and minimized repairing time.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1173-1174
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• 2015

내연 발전기(50 MW, 13.8 kV) 출력단자에서 차단기까지 연결된 13.8 kV XLPE(cross-linked polyethylene) 케이블에서 운전중에 절연파괴로 인해 지락이 발생하였다. XLPE 케이블의 건전성을 확인하기 위해 절연저항과 절연진단 시험을 수행하였다. 교류전압을 1~10 kV까지 증가하면서 XLPE 케이블의 유전정접 측정결과 A상과 C상은 0.1%로 일정하게 측정되었다. 반면에 B상의 유전정접은 1 kV에서 0.54%, 2 kV에서 0.68%, 3 kV에서 0.82%, 4 kV에서 1.12%로 증가하였다. 그리고 교류전압을 약 4.3 kV 인가 중에 진단장비가 차단되었다.

• 대한관절경학회지
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• 제13권1호
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• pp.53-57
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• 2009

The pretibial cyst is a very rare complication after anterior cruciate ligament (ACL) reconstruction. It occurs whatever kind of graft choice or kind of graft fixation method at tibial side. It have been known such as graft necrosis at tibial side, extra-articular leakage of joint fluid through tibial tunnel, foreign body reaction due to breakdown of the bioabsorbable screw and incomplete incorporation of graft to bony tunnel as the cause of pretibial cyst. We experienced one case of pretibial cyst which had undergone ACL reconstruction with autogenous hamstring graft fixed with biodegradable interference screw. We report a rare case of pretibial cyst with literature review.