• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2007.11a
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• pp.187-192
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• 2007

A project is being implemented to develop the long distance energy transport technology using the chemical reactions. This project can be classified into three main research categories covering heat recovery reaction, long distance energy transport, and heat generation reaction. In this study, the methanol is selected as a system material since it shows several unique superior characteristics as follows: gaseous state of reactant and product, large heat of reaction, high yields of reaction at relatively low temperature, and also steady and economical supply. Furthermore, it is anticipated that the outcomes of this study can be widely applied to the related industries. A feasibility study was carried out to evaluate the economics of this technology which study was based on the following case: 10,000 households, 15km distance energy transportation, utilization of waste heat from power plant.

• Journal of Life Science
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• v.11 no.6
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• pp.574-581
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• 2001

This study was performed to evaluate the inhibition effects of fermented soybean on lipid perosidation and antioxidative relative enzyme activity. in vivo. Fermented soybean was induced the high SOD activity, while significantly inhibited on the peroxide value of linoleic acid and lipid perxidation from rat microsome induced by Fe$^{2+}$ ascorbate system, Sprague-Dawley(SD) male rats were fed basic diet, and experimental diets group added 200 or 500 mg/kg fermented soybean for 2 weeks. The effect of fermented soybean is also significantly increased catalase and glutathione peroxidase activities, while significantly inhibited the lipid peroxidation of rat liver microsome in a dose dependent manner. Therefore, these results suggest that fermented soybean has antioxidative activity which is related enzyme to prevention of oxidative stress.s.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.10a
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• pp.159-162
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• 2010

본 연구에서는 화재위험성이 높은 공동주택을 대상으로 실규모의 화재 재현 실험을 실시하였다. 여러 가지 발화 요인중 발생 빈도가 높은 6가지를 선정하여 재현실험을 실시하였으며, 실험결과를 토대로 화재감식 및 화재위험성을 분석하고자 하였다. 실험 결과 발화 후 약 4분이 경과후 화재가 빠른 속도로 성장하다가 5분경에 이르면서 내부로 화재가 완전히 전이 되는 것을 확인하였다. 화재시 발생되는 일산화탄소 농도는 최대 8200 ppm으로 측정되어 유독가스로 인한 질식사의 위험도 매우 높음을 보여주었다. 또한, 화재 현장의 화재감식을 실시함으로써 화재조사관의 현장 감식능력을 배양하고 화재조사경험 및 정보 공유를 위한 실질적인 기회를 제공하고자 하였다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.61-65
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• 2006

A thery was developed to design a high pressure vessel with combined structure of the metal and the composite to withstand the pressure of several tens of thousands psias to reduce the weight of the impulse motor which produces high level of thrust within several tens of seconds. The elastic-plastic stress analyses were carried out to prove the validity of the design theory A combustion chamber of the impulse motor was designed by the design theory, fabricated, and tested by the hydraulic pressure and the static firings. The bursting pressures from the tests were compared to those predicted by tile design theory and the stress analyses and found to be almost the same. It will be possible to design the high pressure vessel with combined structure of the metal and the composite very easily by the proposed design theory.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.2
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• pp.23-30
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• 2006

A thery was developed to design a high pressure vessel with combined structure of the metal and the composite to withstand the pressure of several tens of thousands psias to reduce the weight of the impulse motor which produces high level of thrust within several tens of seconds. The elastic-plastic stress analyses were carried out to prove the validity of the design theory. A combustion chamber of the impulse motor was designed by the design theory, fabricated, and tested by the hydraulic pressure and the static firings. The bursting pressures from the tests were compared to those predicted by the design theory and the stress analyses and found to be almost the same. It will be possible to design the high pressure vessel with combined structure of the metal and the composite very easily by the proposed design theory.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.4
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• pp.419-424
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• 2007

According to increase of consumer's desire for clean tap water, advanced treatment processes include with membrane, ozone, and granular activated carbon(GAC) were introduced. In order to evaluate the effect of advanced treatment processes for residual chlorine decay and trihalomethane(THM) formation in water distribution system, dissolved organic matter(DOC) removal of each advanced treatment process was investigated. The residual chlorine decay and THM formation using bottle tests were also evaluated. $UV_{254}$ removal in all advanced treatment was better than DOC removal. Especially, DOC by ozone treated was removed as 4% in contrast with sand filtered water, but $UV_{254}$ was removed about 17%. This result might be due to convert from hydrophobic DOC to hydrophilic DOC by ozonation. Ozone/GAC process was most effective process for DOC removal. The residual chlorine decay constants in treated water by sand filtration, ozonation, GAC adsorption, and ozone/GAC processes were 0.0230, 0.0307, 0.0117 and 0.0098 $hr^{-1}$, respectively. The sand filtered water was produced 81.8 ${\mu}g/L$ of THM after 190 hours of reaction time, as the treated water by ozone, GAC, and Ozone/GAC was less produced 6.0, 26.2, 30.3% in contrast with sand filtered water, respectively. Consequently, the durability of residual chlorine and reduction of THM formation were improved by advanced treatment processes.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.1
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• pp.42-55
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• 2017

Since the phases and patterns of the climate adaptability of vegetation can greatly differ from region to region, an intensive pixel scale approach is required. In this study, Partial Least Squares (PLS) regression on satellite image-based vegetation index is conducted for to assess the effect of climate factors on vegetation productivity and to predict future productivity of forests vegetation in South Korea. The results indicate that the mean temperature of wettest quarter (Bio8), mean temperature of driest quarter (Bio9), and precipitation of driest month (Bio14) showed higher influence on vegetation productivity. The predicted 2050 EVI in future climate change scenario have declined on average, especially in high elevation zone. The results of this study can be used in productivity monitoring of climate-sensitive vegetation and estimation of changes in forest carbon storage under climate change.

• Applied Microscopy
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• v.29 no.3
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• pp.363-376
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• 1999

This study aims to demonstrate the effect of chitosan oligosaccharide on the ultrastructural changes in the mouse liver toxicated by carbon tetrachloride $(CCl_4)$. A healthy male ICR mouse that weighted $27{\pm}2gm$ was used for experiment. The experimental group was divided into three groups; the group A; the pretreated group with chitosan oligosaccharide, the group B; the simultaneous group, the group C; treated only the $CCl_4$. The group A was simultaneously treated with chitosan oligosaccharide and $CCl_4$ after pretreated with chitosan oligosaccharide for 7 days. The group B injected $CCl_4$ and chitosan oligosaccharide to the intraperitoneal. The group C injected with only $CCl_4$ to the intraperitoneal. The results were as follow: In the group A, the nuclear membrane and the mitochondria were observed almost normal in shapes at overall the time. Some lamellae of the RER (rough endoplasmic reticulum) destructed until 48 hours but ribosome attached. The destructed lamellae reformed at 72 hours but the smooth membrane vesicles not observed. The lysosomes observed at 72 hours. At 96 hours, all organelles showed in normal shapes. In the group B, changes of nuclear membranes were relatively lighter than group C. Mitochondria observed normal shape through the time. Parts of RER reformed the lamellae, other parts dilated inner cavity. And lipid droplet observed around the 24 hours. Glycogen and lysosome observed 48 hours and 72 hours, respectively. In the group C, nuclear membrane was irregular and nuclear cytoplasm condensed through the time. The lamellae of RER destructed from 24 to 96 hours. Smooth membrane vesicles observed in the cytoplasm at 48 ours. Mitochondria was less effected by toxic. And from the 24 hours, the variable sizes of lipid droplets observed in tile cytoplasm. These results suggest that chitosan oligosaccharide attenuates the toxic effect of the carbon tetrachloride in the mouse liver.

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.175-184
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• 2013

Organic carbon and total nitrogen stable isotope ratios of suspended materials were determined at 3 stations (from Mongtan Bridge to Youngsan river estuary barrage) (n=6, each) from November 2008 to August 2009, in order to understand the origin of particulate organic matter at the Estuary of Youngsan River. Allochthonous organic matter, ammonia-N and silicate were increased after heavy rain (in August). Carbon isotope ratios were significantly different between stations in November and August, and it was possible to determine the origin of organic matter. The heavier nitrogen isotope ratios, as well as higher phosphate concentrations, were found in November than other sampling times. Livestock wastewater and farmland input was likely the main causes of these high values. In addition, YS3 station, the nearest site to estuary barrage, appears to be affected by a substantial amount of livestock wastewater and farmland input, considering that nitrogen isotope ratios were heavier than those at the upper sites. These results suggest that the analysis of stable isotope ratios is a simple but useful tool for the determination of organic matter origin in aquatic environments.

• Applied Biological Chemistry
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• v.17 no.3
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• pp.219-234
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• 1974

A series of experiments was conducted to study the behavior of the phosphorus added to the soils having the high phorphorus fixing capacity derived from volcanic ash in Cheju Island. Soil samples were taken from different depths of 0-10, 10-30, and 30-50cm in six citrus orchards where heavy application of phosphate fertilizer has been practised. Various forms of phosphorus were determined and phosphorus adsorption experiments were performed. The results obtained can be summarized as follows: 1. The content of inorganic phosphorus fractions determined by the method of Chang and Jackson was: water soluble P