• 조명전기설비학회논문지
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• 제22권12호
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• pp.164-175
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• 2008

안개 및 대기의 교란이 광무선 통신에 주는 영향을 해석하기 위해 가시광선영역의 LD(laser diode) 및 적외선 영역의 LD 사용하고, 카세그레인 광학계를 이용하여 광을 송수신하게 하였으며, 광 소신소자로는 APD(avalanch photo diode)를 사용함을 가정하여 대기 중의 안개의 정도에 따른 가시도 및 교란의 세기를 나타내는 굴절률 구조상수에 따른 광 수신 전력, 잡음 전력을 고려한 SNR(signal to noise ratio)을 계산해 보고 각각의 통신 상태에서 BER(bit error rate)이 $10^{-9}$이 가능한 통신 거리를 알아보았다.

• 대한원격탐사학회지
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• 제37권1호
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• pp.97-110
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• 2021

Fog can cause large-scale human and economic damages, including traffic systems and agriculture. So, Korea Meteorological Administration is operating about 290 visibility meters to improve the observation level of fog. However, it is still insufficient to detect very localized fog. In this study, high-resolution grid-type visibility data were retrieved from irregularly distributed visibility data across the country. To this end, three objective analysis techniques (Inverse Distance Weighting (IDW), Ordinary Kriging (OK) and Universal Kriging (UK)) were used. To find the best method and parameters, sensitivity test was performed for the effective radius, power parameter and variogram model that affect the level of objective analysis. Also, the effect of data distribution characteristics (level of normality) on the performance level of objective analysis was evaluated. IDW showed a relatively high level of objective analysis in terms of bias, RMSE and correlation, and the performance is inversely proportional to the effective radius and power parameter. However, the two Krigings showed relatively low level of objective analysis, in particular, greatly weakened the variability of the variables, although the level of output was different depending on the variogram model used. As the level of objective analysis is greatly influenced by the distribution characteristics of data, power, and models used, care should be taken when selecting objective analysis techniques and parameters.

• Asian Journal of Atmospheric Environment
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• 제7권1호
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• pp.1-7
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• 2013

To establish the method for investigating the behavior of aerosol particles deposited on the leaf surface against fog water under natural conditions, scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) analysis and wash water analysis by ion chromatography after the washing treatment were performed using leaves of white birch collected from low part of the tree crown and the top of the tree in Sapporo City, Hokkaido, northern Japan. Each of collected leaves was divided into two parts according to the treatment performed: leaf surface (adaxial side) was 1) untreated, and 2) washed with deionized water with a pipette. In untreated samples, many particles of various shapes, including soil particles and organic debris, were deposited on the surface. Particles containing S were found on the surface of samples collected from only low part of the tree crown. After the washing treatment, SEM-EDX analysis revealed that soil particles and particles containing S had been washed off with water, although some particles such as soil particles and organic debris still remained on the leaf surface. The major anion such as $SO{_4}^{2-}$ was detected in wash water of all samples, although the peak of S in X-ray spectra was not detected from samples collected at top of the tree. The combination of SEM-EDX analysis with wash water analysis indicated that $SO{_4}^{2-}$ was deposited on the leaf surface in dissolved state and/or in state of submicron particles. These results suggested that fog water could remove soil particles and particles containing S and $SO{_4}^{2-}$ from the leaf surfaces, but not all particles. There was no difference in sampling position in the tree crown. Our study suggested that combination with SEM-EDX analysis and wash water analysis would be effective for investigation of the behavior of particles on the leaf surface against fog water.

• 생물환경조절학회지
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• 제15권3호
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• pp.211-216
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• 2006

지열을 이용한 열펌프 시스템이 온실의 냉방과 과채류의 묘소질에 미치는 영향을 구명하였다. 온실 내 기온은 주간에는 차광구에 비해서 포그+차광구가 $3{\sim}4^{\circ}C$ 낮았고, 야간에는 지열-펌프+차광구가 차광 및 포그+차광구에 비해 $5{\sim}7^{\circ}C$ 낮았다. 오이, 고추 및 토마토 묘의 초장은 차광이나 차광+포그구에 비해 지열-열펌프+차광구가 가장 짧았고, 엽면적과 건물중은 지열-열펌프+차광구가 다른 처리에 비해 약간 작았다. 결과적으로 건묘지수는 지열을 이용하여 냉방을 한 지열+차광구는 포그+차광구 및 차광구에 비해 모두 높게 나타났다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1413-1415
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• 1998

This study deals with the aging effect of EPDM, to understand the surface hydrophobicity mechanism and electrical characteristics due to UV irradiation and salt fog. A mini chamber was fabricated for this test. The specimen was subjected a specific aging cycle. With the result of various analysis methods and investigation, we could make a advanced understanding to the aging mechanism, like as the relationships of the surface morphology and surface electrical characteristics.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.258-261
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• 2001

In this paper, aging characteristics of silicone rubber used for outdoor insulation have been investigated with regards to salt fog condition and heat aging effect. We look over the change of properties of silicone rubber in salt fog chamber with average leakage current monitoring for observing the transformation of surface degradation properties of silicone rubber with different ATH(alumina trihydrate, $Al_2O_3{\cdot}3H_2O$) filler contents. Surface resistivity, SEM(Scanning Electro Microscope) were measured.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.258-261
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• 2001

In this paper, aging characteristics of silicone rubber used for outdoor insulation have been investigated with regards to salt fog condition and heat aging effect. We look over the change of properties of silicone rubber in salt fog chamber with average leakage current monitoring for observing the transformation of surface degradation properties of silicone rubber with different ATH(alumina trihydrate, Al$_2$O$_3$$.$3H$_2$O) filler contents. Surface resistivity, SEM(Scanning Electro Microscope) were measured.

• Journal of Photoscience
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• 제3권2호
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• pp.65-69
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• 1996

In this paper, it was studied about the red-sensitive layer. UV-Vis data of the dye at monomeric and J-state were considered with respect to their performance(contrast, density and fog) in photographic emulsion. The sensitizing effect of the dye is found to be strongly structuredependent. Naphthothiazolo carbocyanine dye can be used as red-sensitizing dye for the spectral sensitization of photographic emulsion.

• 생물환경조절학회지
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• 제25권1호
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• pp.24-29
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• 2016

본 연구는 여름철 참외 시설재배시 저압포그 처리에 의한 온도하강 및 과실 품질 향상 효과를 구명하기 위하여 수행하였다. 2015년 7월 26일 10시부터 18시까지의 하우스 내부의 평균 온도는 무처리구 $43.0^{\circ}C$에 비해 저압포그 처리구에서 $35.4^{\circ}C$로 무처리구에 비해 $7.6^{\circ}C$ 정도 낮았다. 8월 13일 과실의 특성을 조사한 결과, 과중은 무처리구의 432g에 비해 96g 더 가볍고. 과육부 당도 $11.0^{\circ}Brix$에 비해 $1.3^{\circ}Brix$ 더 높았으며 색도(a값)도 5.1에 비해 1.5 더 높아 우수하였다. 6월 23일부터 50일간 참외의 품질을 조사한 결과, 기형과율은 무처리구의 42.6%에 비하여 저압포그 처리구에서는 27.3%로 15.3%p 감소하였고, 상품과율은 무처리구의 57.4%에 비하여 저압포그 처리구에서 72.7%로 15.3%p 증가하였다. 10a당 수량은 무처리구의 2,234kg에 비하여 저압포그 처리구에서 26% 증가하였다. 이상의 결과를 보아, 여름철 고온기 참외 시설 재배시 저압포그 처리로 온도하강 효과가 우수하여 품질이 향상되고 수량이 증가한 것으로 판단되었다.

• 조명전기설비학회논문지
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• 제16권4호
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• pp.30-37
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• 2002

본 논문은 옥외용 절연재료로 사용되는 싸이클로알리파틱계 에폭시 재료의 여러 가지 컴파운드 비에 따른 내후성, 내트래킹 및 염무시험 결과를 나타낸 것이다. 시험 결과, 내후성 시험 동안의 자외선 조사로 인하여 표면에 결합쇄의 절단으로 표면 발수성 손실이 나타났다. 자외선 차단제와 산화안정제 및 실리콘 오일 첨가제가 포함된 시료에서 내후성이 우수한 것으로 나타났으며, 충전재 중 ATH가 포함된 시료에서 내트래킹성의 향상을 확인하였다. 염무시험에서는, 에폭시 수지 내에 실리콘 오일 성분이 포함된 시료가 누설전류 억제 효과를 나타내었다. 본 논문을 통하여 옥외용 절연재료로 사용되는 싸이클로알리파틱 절연재료의 옥외성능에 실리콘 오일성분이 표면에너지를 낮추고 발수성을 오랜 기간 유지할 수 있어 옥외 성능에 바람직함을 알 수 있었다.