• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 하계학술발표대회 논문집
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• pp.102-102
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• 2007

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.175-176
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• 2015

Insulation in buildings are one of the crucial factors for energy reduction, and depending on the application areas and properties of the insulation requirements, various different types of insulation materials are being developed, produced, and used. Amongst these is the aircaps often used as packing materials. Because of their porous nature, they are highly efficient in preventing heat and are consequently used overseas often as insulation materials and as part of cold water concrete insulation curing method. This paper studies the recently developed usage of aircaps in waterproofing materials and evaluated their performance as supplementary insulation materials.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• 제23권1호
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• pp.1-11
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• 1995

Thermospheric neutral winds and temperatures have been collected from the ground-based Fabry-Perot interferometer (FPI) at Thule Air Base ($76.5^{\circ}N{\;}69.0^{\circ}W$), Greenland since 1985. The thermospheric observations are obtained by determining the Doppler characteristics f the [OI] 6300 ${\AA}$ emissions of atomic oxygen. The FPI operates routinely during the winter season, with a limitation in the observation by the existence of clouds. For this study, data acquired from 1985 to 1991 were analyzed. The neutral wind measurements from these long-term measurements are used to investigate the influence of solar cycle variation on the high-latitude thermospheric dynamics. These data provide experimental results of the geomagnetic polar cap are also compared with the predictions of two semiempirical models : the vector spherical harmonics (VSH) model of Killeen et al. (1987) and the horizontal wind model (HWM) of Hedin et al. (1991). The experimental results show a good positive correlation between solar activity and thermospheric wind speed over the geomagnetic polar cap. The calculated correlation coefficient indicates that an increase of 100 in F10.7 index corresponds to an increase in wind speed of about 100 m/s. The model predictions reveal similar trends of wind speed variation as a function of solar activity, with the VSH and HWM models tending to overestimate and underestimate the wind speed, respectively.

• Journal of Biosystems Engineering
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• 제26권4호
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• pp.331-336
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• 2001

This study was to develop a kerosene flame weeder. An air compressor was driven though the PTO of a tractor to provide necessary air for fuel combustion and proper pressure to supply fuel from fuel tank to the nozzle. It was found that the flame was extinguished very easily by wind and vibration of the tractor. This trouble could be solved by attaching a burner cap, which is a modified venturi tube, at the end of the nozzle. The constructed flame weeder was tested for the weeding capability in the prepared field. Weed extinction rate and weight decrease rate were analysed. Measured maximum flame temperature was 1,121$\^{C}$ when the fuel consumption was 13.41 kg/h and fuel supply pressure was 88.2 kPa. The maximum temperature occurred at 20cm from the front end the burner, and it decreased to 46$\^{C}$ as the distance increased to 110cm. The flame length of up to 70cm, where the flame temperature was higher than 372$\^{C}$, would be used for weeding purpose. Weed extinction rate and weight decreasing rate increased as the fuel consumption increased. The flame weeder was evaluated to be a practical weeder through improvement as the weed extinction rate and weight decrease rate were analysed to be 75% and 85%, respectively when the fuel consumption was 116.87kg/ha.

• 한국식품영양과학회지
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• 제14권4호
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• pp.419-427
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• 1985

삿갓이 완전히 펴진 표고버섯의 부위별(別)에 따른 지질(脂質)의 특성(特性)과, 삿갓이 펴지지 않은 표고버섯의 건조방법(乾燥方法)에 따른 지질(脂質)의 변화(變化)를 연구(硏究)한 결과(結果)는 다음과 같다. 1. 삿갓이 펴진 표고버섯의 삿갓부위(部位)의 총지질(總脂質) 함량(含量)은 4.58%이었고 자루부위(部位)는 2.6%이었으며 거의 대부분(大部分)이 중성지질(中性脂質)$(46.7{\sim}48.8%)$과 연지질(憐脂質)$(42.0{\sim}43.8%)$로 구성되어 있었으며 탕지질(糖脂質)은 적었다$(9.2{\sim}9.5%)$. 2. 중성지질(中性脂質)의 주요성분(主要成分)은 tryacylglycerol이었고 연지질(憐脂質)은 phosphatidyl ethanolamine이었다. 또한 지질산(脂質酸)의 조성(組成)은 각지질(各脂質) 및 부위(部位)에 따라 현격하게 달랐으며 $C_{18:2},\;C_{16:1}$ 및 $C_{18:1}$ 지방산(脂肪酸) 순(順)으로 함유(含有)되어 있었다. 3. 삿갓이 펴지지 않은 표고버섯의 총지질(總脂質)은 2.5%(자루)${\sim}3.7%$(삿갓)이었고 총지질함량(總脂質含量), 과산화물가(過酸化物價) 및 카아보닐價(價)는 건조방법(乾燥方法)에 따른 차이(差異)를 보이지 않았으며 총지질(總脂質)의 산가(酸價)는 일건시료(日乾試料)가 생시료(生試料) 및 열풍건조시료(熱風乾燥試料) 보다 약간 낮았으나 일건시료(日乾試料) 중(中)의 중성지질함량(中性脂質含量)은 다른 시료(試料)보다 높았다. 4. 가장 많은 部分을 차지한 중성(中性) 및 연지질(憐脂質)의 주요성분(主要成分)의 삿갓이 완전히 펴진 표고버섯과 같았고 탕지질(糖脂質)은 digalactosyldiglycerol이었으며 일건시료(日乾試料)의 연지질중(憐脂質中) phosphatidiyl ethanolamine과 phosphatidyl choline함량은 생시료(生試料) 및 열풍건조시료(熱風乾燥試料)보다 낮았다. 5. 모든 건조시료의 각(各) 지질(脂質) 중(中)의 주요(主要) 지방산조성은 삿갓이 펴진 시료의 경우와 비슷하였고 일건시료(日乾試料)의 $C_{18:2}$ 지방산(脂肪酸)함량은 다른 시료보다 높은 반면 $C_{16:0}$ 지방산은 낮았다. 한편일건시료 중의불포화지방산 함량은 열풍건조시료 및 생(生)시료보다 낮았다.

• 대한환경공학회지
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• 제28권11호
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• pp.1112-1117
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• 2006

• 대한방사선치료학회지
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• 제6권1호
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• pp.89-93
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• 1994

Authors have measured virtual source distance of electron beam from CL/1800 medical linear accelerator, with newly designed method. Beam scanning was performed with the direction of beam axis in the air. Compared results between this study and well established in phantom measurement shows good agreement with in experimental error. And we have found that build-up cap plays very important role in air measurement because of charge build up. The method of in-air measurement of virtual source distance is very easy to set-up and generate accurate results.

• 한국작물학회지
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• 제43권2호
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• pp.77-82
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• 1998

Aerenchyma development in rice (Oryza sativa L.) roots is quite important for adaptation to waterlogged or reduced soil conditions. Anatomical observations were carried out to clarify the development of schizogenous and lysigenous aerenchyma in elongating crown roots of rice. The crown roots of 3rd and 4th phytomer were taken from rice plants of the 8th leaf stage grown by hydroponic culture. The schizogenous intercellular spaces in the cortex of crown root tip were observed using a light microscope with semi ultra-thin sections and the lysigenous aerenchyma in mature tissue of crown root were observed using a cryo scanning electron microscope (cryo-SEM) with freezing fracture method. The schizogenous intercellular spaces in the root tip exist obviously in the middle portion of cortical cell layers close to the root-root cap junction, but not in root cap, stele and outer cell layers of cortex. The air spaces were formed at the junction of four neighbouring cells of inner cortex in the transverse sections, and between longitudinal cell layer connected along the root axis. Although many of those spaces were filled with liquid, some spaces seem to exist as air spaces. The lysigenous aerenchyma in the cortex, which hardly filled with liquid, emerged at 3-4 cm segment from the root tip and increased toward the basal region of root axis. The developing process of lysigenous aerenchyma was primarily separation of a radial row of cells caused by the shrinking and collapsing of cortical cells and then formation of septa along the radial cell rows by the fusion of cell wall with each other. These results suggest that the schizogenous and lysigenous aerenchyma playa role as a passage for the movement of oxygen into the root tip region where oxygen is required for respiration.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2008년도 추계학술대회 논문집
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• pp.71-72
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• 2008

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.23-27
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• 2002

Two $^{192}$ Ir HDR brachytherapy sources were calibrated with a Farmer ionization chamber in air method and in a PMMA cylindrical phantom. The calibration air method used ionization chamber with buildup cap, and 8 variation distances for center-to-center of the source to chamber. In the optimum distance the measured activity, especially for the high activity source, deviation was 0.3% from the activity provided by manufacturer. Calibration with a PMMA cylindrical phantom was less sensitive, and suitable for quick check method with accuracy less than 10%.