• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 추계총회 및 학술대회 논문집
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• pp.124-124
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• 2012

부식 현상은 산업과 실생활에서 경제적, 인간의 생활과 안전에서 손실을 일으키는 요인이다. 자동차 부품, 선박 부품 및 전자 부품 산업 등 다양한 분야에서 수명 및 고장율 시험에 대한 관심이 증가하고 있다. 넓은 분야에서 염수분무시험을 적용하고 있지만, 실제 야외환경에서 발생하는 부식과의 상관관계가 확실하게 규명되어 있지 않다. 그리고 이렇게 넓은 산업전반에서 적용하고 있는 염수분부시험 방법은 시료의 부식 저항성을 판단하기 위한 시험시간이 오래 걸리고 이런 이유로 적정한 시험시간을 설정하기 어려울 뿐만 아니라 고내식성 시료의 부식평가가 어렵다는 단점을 가지고 있다. 본 연구에서는 부식의 형태에서 균일부식 현상을 이용하여 옥외 노출 부식시험과 염수분무시험, 가속부식시험 환경에 노출된 시료의 무게 감량을 측정하여 가속계수 도출과 함께 부식 정도를 예측할 수 있는 방법을 연구하였다.

• 한국통신학회논문지
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• 제29권3A호
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• pp.288-292
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• 2004

최근 들어 hot spot 서비스를 비롯한 무선랜의 활용이 급격히 증가하고 있다. 전에는 주로 옥내에서 유선랜 대용으로 사용이 국한되었지만, 무선랜의 데이터 전송속도와 성능이 크게 향상되어 옥내에서의 mobile computing 용도뿐만 아니라 옥외에서 인터넷 접속용이나 무선 브리지용으로도 그 사용이 증대되고 있다. 본 논문에서는 고속이동환경에서의 무선랜의 데이터 전송속도를 측정하여 ITS(Intelligent Transport System)나 Telematics, LBS(Location Based System) 등의 응용 분야에서 그 사용 가능성을 검증하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2408-2410
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• 1999

The ageing process was checked by leakage current monitoring in Inclined-Plane Method. In order to monitor leakage current, DAS with 12-bit, 8-channel A/D converter was prepared. The monitored components of leakage current were averages of the rms and peak, max peak, cumulative charge, and the number of peaks in the ranges of 1-10, 10-20, 20-30, 30-40, 40-50, >50 mA. And, erosion depth was measured to be used as the index of the ageing. So, the results of leakage current components and erosion depth measurement were compared to find one or more components of which trends of changes were similar to that of erosion.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.212-216
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• 2001

The conventional tracking testing as IEC-60587 is widely used in surface aging measurement of outdoor insulator because those testing can carry out very short time in Lab-testing. Also IEC-60587 testing is able to offer the standard judgement of relative degradation level of outdoor HV machine/system. Therefore it is very useful method compare to previous conventional tracking testing method and effective Lab-testing method. But surface discharges(SD) have very complex characteristics of discharge pattern so it is required estimation research to development of precise analysis method. In recent, the study of IRR-camera is carrying out discover of temperature of power equipment through condition diagnosis and system development of degradation diagnosis. In this study, SD occurred from procelain insulator, used 22.9[KV] distribution, is measured with partial temperature distribution in real time, the degradation grade of SD is analyzed through produced patterns in SD concentration according to applied time.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.106-109
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• 2001

In this paper, we have investigated the degradation of shed materials of outdoor insulators by UV-radiation by using corona-charging and XPS analysis. The accumulated charges on polymeric surface having intrinsic hydrophobic property have a negative impact on retaining its hydrophobicity. Therefore, shorter decay times of surface charges are preferred. The surface voltage decay on UV-treated silicone rubber and EPDM show a different decay trend with UV treated time. From the XPS analysis, the oxidized groups of silica-like structure in silicone rubber increase with UV treatment time. For EPDM, the oxidized carbon groups of C=O, O=C-O increase as elapse of UV radiation time. These oxidized surface for each material have different electrostatic characteristics, so deposited charges may be expected to have different impacts on their surface hydrophobicity. The degradation mechanism based on our results is discussed.

• 한국전기전자재료학회논문지
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• 제20권2호
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• pp.183-187
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• 2007

Fractal mathematics is being highlighted as a research method for classification of image. But the application of Fractal dimension(FD) has been requited the complicated calculation method because of its complex repetition progressing. In this paper, it has been developed the new approach method to express the Fractal Dimension(FD) for aging level calculation and estimation system of outside insulator using special image processing algorithm. As a result after FD testing, the recognized aging estimation of FD has a very characteristics compared to the conventional visual inspection.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.214-215
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• 1994

The VCB(Vacuum Circuit Breaker), which has been used in power distribution system, have prevented the performance of the phase modifying equipment (Condenser Bank and Shunt Reactor) and the important parts in the electric power system because of the transient voltage in opening and closing circuit. So, we developed the 25.8kV $SF_6$ gas GCB(GAS Circuit Breaker), which had the few occurance of the surge in opening & closing circuit and had the high reliability, based in our own technology.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1500-1502
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• 1997

We investigated the tracking and erosion resistance of the silicone rubber by Inclined-Plane Method. And, with the variation of the accelerated conditions such as the applied voltage and composition of contaminant, the change of the tracking characteristics according to such conditions was evaluated. The leakage current significantly increases with the increasing voltage, but the weight loss remains almost the same. The voltage above 5.0 kV isn't recommended because tracking breakdown occurs as fast as it does without erosion, and the typical discharge waveform was the form of rectifying wave.

• 한국태양에너지학회 논문집
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• 제28권3호
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• pp.27-34
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• 2008

A series of outdoor tests were conducted on a fiber optic solar concentrator system for its performance on daylighting. The system is comprised of four main components - a parabolic dish reflector, a convex mirror, a homogenizer tube and an optical fiber cable. Results show that the system could be successfully applied for indoor lighting if some improvements are made for light transmiting (optical) cables. A maximum concentration ratio of 90 was observed delivering the illuminance of 4,800 lux at a distance of 1.2m from the diffuser for the outdoor illuminance of 102,100 lux.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.877-882
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• 2008

The purpose of this study is to analyze the characteristics of outdoor thermal environment of flat-type apartment houses and tower-type apartment houses in summer by numerical simulation. After inputting a building condition at CAD, we calculated the surface temperature for two apartments by using the numerical simulation of a clear sky day in summer in Seoul. The results indicated that the variation in Heat Island Potential(HIP) of tow apartments were not only in the day but also in the night. According to form of apartment the flat-type apartment houses appeared $1.3^{\circ}C$ more highly tower-type apartment houses.