• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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• pp.221-226
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• 2001

HANARO, 30MW of research reactor, was installed at the depth of 13m of open pool, The $90\%$ of primary coolant was designed to pass through the core and to remove the reaction heat of the core. The rest $10\%$, of the primary coolant was designed to bypass the core. And the reactor coolant through and bypass the core was inhaled at the top of chimney by the coolant pump to protect that the radiated gas was lifted to the top of reactor pool. But, the part of core bypass coolant was not inhaled by the reactor coolant pump and reached at the top of reactor pool by natural convection and increased the radiation level on the top of reactor pool. To reduce the radiation level by protecting the natural convection of the core bypass flow, the hot water layer (HWL, hereinafter) was installed with the depth of 1.2m from the top of reactor pool. As the HWL was normally operated, the radiation level was reduced to five percent ($5\%$) in comparing with that before the installation of the HWL. When HANARO was operated with higher temperature than the normal temperature of the HWL by operating the standby heater, it was found that the radiation level was more reduced than that before operation. To verify the reason, the heat loss of the HWL was calculated. It was confirmed through the results that the larger the temperature difference between the HWL and reactor hall was, the more the evaporation loss was increased. And it was verified that the radiation level above was reduced more safely by increasing the capacity of heater.

• Journal of Radiation Protection and Research
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• 제31권3호
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• pp.115-122
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• 2006

We have screened the cytoprotective effect on $\gamma$-ray radiation induced oxidative stress from eighteen Korean plant extracts. Querus salicina, Clerodendron trichotomum, Lamium amplexicaule, Lozoste lancifolia and Malus baccata were found to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and intracellular reactive oxygen species (ROS). As a result, extracts of these plants reduced cell death of Chinese hamster lung fibroblast (V79-4) cells induced by $H_2O_2$ treatment. In addition, these extracts protected cell death of V79-4 cells damaged by $\gamma$-ray radiation. In addition, these extracts scavenged ROS generated by radiation. Taken together, the results suggest that Quercus salicina, Clerodendron trichotomum, Lamium amplexicaule, Lozoste lancifolia and Malus baccata protect V79-4 cells against oxidative damage by radiation through scavenging ROS.

• 한국식품영양과학회지
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• 제45권7호
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• pp.948-957
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• 2016

본 연구팀에서는 방사선에 의한 면역조혈계 및 위장관계 손상에 대한 방호를 위하여 당귀, 천궁, 작약 혼합물의 열수 추출물로부터 그 다당체 함량을 강화한 생약조성물 Hemo HIM을 개발한 바 있다. 본 연구에서는 열수 추출물에 기반을 두어 제조된 HemoHIM에 비하여 지용성 폴리페놀 성분을 강화함으로써 더 뛰어난 생리활성을 갖는 생약조성물을 개발하고자 30% 에탄올 추출과 열수 추출을 함께 시행하여 얻은 추출물을 기반으로 생약조성물 MH-30을 제조하였다. MH-30과 HemoHIM의 에탄올 분획 내의 성분을 HPLC로 비교 분석한 결과 수용성 성분에는 큰 차이가 없었으나 여러가지 지용성 성분이 MH-30에서 크게 증가하는 것을 확인하였으며, 특히 decursin의 함량은 8.7배로 크게 증가하였다. 다음으로 MH-30의 시험관 내 항산화 및 면역세포 활성화 효과와 방사선 조사 마우스에서 면역조혈계 및 재생조직의 방호 효과를 HemoHIM과 비교하여 관찰하였다. 항산화 활성을 비교하기 위한 시험관 내 hydroxyl radical 및 superoxide anion 소거 활성 평가에서 MH-30이 HemoHIM보다 높은 항산화 활성을 보였다. 림프구 증식능을 이용한 시험관 내 면역세포 활성화 시험에서는 MH-30과 Hemo HIM은 거의 비슷한 활성을 나타내었다. 방사선 조사 마우스에서 MH-30은 내재성 비장 조혈세포 집락수를 증가시키고 골수조직 내 세포사멸을 줄였으며, 위장관 재생조직인 소장움의 생존율을 증가시키는 등 방사선에 의한 면역조혈계와 재생조직 손상을 방호하는 효과를 보여주었다. 또한, 종합적인 방사선 방호 효과를 평가하는 지표인 방사선 조사 마우스의 30일 생존율도 MH-30 투여로 유의하게 증가함을 확인하였다. 특히 상기한 모든 마우스 실험에서 MH-30은 Hemo HIM보다 더 뛰어난 방호 효과가 있음을 관찰할 수 있었다. 이상의 결과들은 새롭게 개발한 생약조성물 MH-30이 면역 조혈계와 재생조직의 방사선 손상을 줄여주는 효과가 있으며 기존에 개발된 HemoHIM에 비해 더 뛰어난 활성을 갖고 있음을 보여주었다. 따라서 MH-30은 방사선 사고 또는 암환자의 방사선치료 시 발생할 수 있는 면역조혈계 및 재생조직의 손상을 경감시킬 수 있는 방사선 방호 물질로서 유용하게 활용될 수 있을 것으로 생각한다.

• 대한전자공학회논문지TC
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• 제40권11호
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• pp.72-76
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• 2003

마이크로 스트립 선로 구조에서 접지면에 슬롯을 갖는 DGS는 디지털 회로의 스위칭 모드 잡음에 의한 영향으로부터 아날로그/RF 회로를 보호할 수 있다. 그러나 기본적인 구조는 접지면의 불연속에 의해 불요 전자파를 기준값 이상으로 방사하여 전자파 장애를 일으킬 수 있다. 본 논문에서 제안된 구조인 주름진 DGS는 전자파 방사를 상대적으로 억압할 수 있으며 또한 슬롯에 저항을 두고 이를 이용하여 전자파 방사의 억압을 제어할 수 있다.

• Journal of Advanced Marine Engineering and Technology
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• 제27권4호
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• pp.479-486
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• 2003

This paper presents the Performance of PV(Photovoltaic) system. the design of MPPT and the battery characteristic. The output power of PV depends on the environmental factors such as insolation and cell temperature. It is proposed that the MPPT is based on an simple power control algorithm. Furthermore the converter has to maintain the optimum duty ratio. A switching strategy of converter for battery may Protect against excessive discharge and overcharge. This paper includes discussion on system reliability power quality and effects of the randomness of the wind and the solar radiation on system design.

• 한국포장학회지
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• 제12권1호
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• pp.45-53
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• 2006

Thermal insulation is used in a variety of applications to protect temperature sensitive products from thermal damage. Several factors affect the performance of insulation packages. Among these factors, the thermal resistance of the insulating wall is the most important factor to determine the performance of the insulating package. In many cases, insulating wall consists of multi-layered structure and the heat transfer through this structure is a very complex process. In this study, an one-dimensional mathematical model, which includes all of the heat transfer principles covering conduction, convection and radiation in multi-layered structure, were developed. Based on this model, several heat transfer phenomena occurred in the air space between the layer of the insulating wall were investigated. From the simulation results, it was observed that the heat transfer through the air space between the layer were dominated by conduction and radiation and the low emissivity of the surface of each solid layer of the wall can dramatically increase the thermal resistance of the wall. For practical use, an equation was derived for the calculation of the thermal resistance of a multi-layered wall.

• BMB Reports
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• 제47권4호
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• pp.209-214
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• 2014

Ultraviolet B (UVB) radiation induces the production of reactive oxygen species (ROS) that promote apoptotic cell death. We showed that cytosolic $NADP^+$-dependent isocitrate dehydrogenase (IDPc) plays an essential role in the control of cellular redox balance and defense against oxidative damage, by supplying NADPH for antioxidant systems. In this study, we demonstrated that knockdown of IDPc expression by RNA interference enhances UVB-induced apoptosis of immortalized human HaCaT keratinocytes. This effect manifested as DNA fragmentation, changes in cellular redox status, mitochondrial dysfunction, and modulation of apoptotic marker expression. Based on our findings, we suggest that attenuation of IDPc expression may protect skin from UVB-mediated damage, by inducing the apoptosis of UV-damaged cells.

• 대한가정학회지
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• 제42권1호
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• pp.99-113
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• 2004

To protect farmers from solar radiation and UV, the movable sunshade tent was designed and its protection efficiency was measured in the artificial chamber and outdoors. Sunshade tent and the existing farmer's hat were examined. The results were as followes； Heart rate, total body weight loss and temperature of clothing microclimate on the chest and the back were lower in using sunshade tent than those in wearing existing hat in two experiments. In subjective sensation, subjects answered to feel significantly hotter and more uncomfortable in wearing existing hat in two experiments. Rectal temperature was significantly lower using the sunshade hat in experiment at outdoors(p<0.001).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 D
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• pp.2828-2830
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• 2000

When changing old parts of the System or establishing new system of the Nuclear power plane it's contribution that given effective economics and learning radiation detector and protect contamination for human, It will be contributed to minimizing pollution of employee for radioactivity as spread of supply with the products in cheaper price then foreign products in new or existing N.P.P.

• 한국환경과학회지
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• 제11권10호
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• pp.1117-1123
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• 2002

Coating ceramic balls activate water molecular in water as radiate far-infrared radiation of high efficiency, and then prevent formation of scale and corrosion of pipe. Therefore, but only keep away drop of heat exchange efficiency of boiler, not also remove formed scale. As a result, pipe of boiler has clean and has form thin protection film in inner of pipe. Also, the water treated by rust preventing system using the ceramic balls, that is harmless, tasteless, odorless, and non-toxicity in the human body, and it can use drinking water. This rust preventing system can save energy and protect environment.