• 환경영향평가
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• 제19권1호
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• pp.1-13
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• 2010

Ammonia ($NH_3$) is an important pollutant that plays a key role in several air pollution problems. It can create odors and have negative impacts on animal and human health. The largest source contributing to Ammonia emission is the agricultural production, in particular animal operation, in Korea. The present study evaluated flux profiles of Ammonia emitted from the cattle housing using a dynamic flux chamber. We have developed the emission factor of Ammonia from the cow housing. Analysis of Ammonia flux variation was made with respect to manure surface temperature, pH, and ammonium concentration. Ammonia has been measured from calf and cattle housing between October and December in 2007. In the fall, average Ammonia flux from calf and cattle housing was estimated 1.342(${\pm}0.728$) and 1.323(${\pm}0.655$)mg/$m^2$/min, respectively. In the winter, average Ammonia flux was estimated 0.889(${\pm}0.362$)mg/$m^2$/min from the calf housing and 0.925(${\pm}0.511$)mg/$m^2$/min from the cattle housing. The correlation coefficient between Ammonia flux and ammonium concentration showed stronger relationship than the relationship between manure pH and temperature. In the fall, Ammonia emission factor from calf and cattle housing was estimated 4.46(${\pm}2.39$) and 6.03(${\pm}3.27$)kg-$NH_3$/animal/yr, respectively. In the winter, average Ammonia flux was estimated 2.88(${\pm}1.53$) from the calf housing and 4.24({$\pm}1.63$)kg-$NH_3$/animal/yr from the cattle housing.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1918-1920
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• 2005

The color and structure of urban constructions is a factor of urban landscape and shows their characteristics. Hence the modern buildings with their materials and external appearance makes up the urban image. But still yet, it was not easy to evaluate the value of visual landscape of buildings with objective measuring method. Most of all, it depends on the subjective estimation of a few talented or high educated experts with a sense of beauty. In relation to this kind of problems, it was tried here in this study to analyse the human response of brain wave pattern (EEG) with use of SD method, while the tested persons watched the urban landscape constructed in a visual reality. The tested persons were 10 adult males and females with no color blindness and intact cognitive function. Light source with color filter was used for color environment in chamber room. The signal of EEG is analysed digitally and grouped into the $\alpha$ and $\beta$ waves. The result showed that relative power of $\alpha$ wave ratio increased in natural landscape scenary clearly. From these results it was possible to evaluate the human response, which was affected by urban color and structure stimulation and it might be useful as an indicator of visual cognition amenity toward the design of urban construction environment.

• 한국물환경학회지
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• 제29권2호
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• pp.184-195
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• 2013

Urbanization from agricultural/forest areas has been causing increased runoff and pollutant loads from it. Thus, numerous models have been developed to estimate NPS loading from urban area and Long-Term Hydrologic Impact Analysis (L-THIA) model has been used to evaluate effects of landuse changes on runoff and pollutant loads. However, the L-THIA model could not consider rainfall intensity in runoff evaluation. Therefore, the L-THIA model, capable of simulating runoff using 10-minute rainfall data, was applied to the study areas for evaluation of estimated runoff and NPS. The estimated Nash-Sutcliffe coefficient (NSE) values were over 0.6 for runoff, BOD, TN, and TP for most sites and watershed. The calibrated model was further extended to other counties for pollutant load potential evaluation. Pollutant load potential maps were developed and target areas were identified. As shown in this study, the L-THIA 2012 can be used for evaluation runoff and pollutant loads with limited data sets and its estimation could be used in identifying pollutant load hot spot areas for implementation of site-specific Best Management Practices.

• 한국해안·해양공학회논문집
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• 제23권1호
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• pp.11-17
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• 2011

항만콘크리트 구조물의 내구성 저하의 중요한 요인은 염소이온침투에 의한 철근의 부식이다. 따라서, 항만콘크리트 구조물의 염소이온 깊이와 깊이별 염소이온농도를 정량적으로 파악할 수 있다면, 구조물의 잔존수명을 사전에 비교적 정확하게 평가할 수 있다. 이러한, 구조물에서의 염소이온농도를 예측하기 위해서는 모델식의 개발이 필요하고 모델식은 정확한 현장데이타를 기반으로 한다. 이에 본 연구에서는 현장 항만구조물에 대한 코어시료를 채취하고 본 시료들에 대한 염소이온침투깊이와 깊이별 염소이온농도를 측정하고자 하였다. 시료는 1차로 완도항, 마산항, 인천항에서 채취하였고, 2차로 여수항과 동해항에서 채취하였다. 수직 높이별 영향을 파악하기 위해서 대기부, 비말대, 간만대로 나뉘어 각 층별 8개의 시료를 획득하였다. 채취된 시료중에서 4개는 강도 실험을 실시하였고, 나머지 4개로 내구성 실험을 실시하였다. 2개의 시료에 대해서는 질산은 변색법을 이용하여 염소이온 침투깊이를 측정 하였다. 나머지 2개의 시료는 깊이별로 5 mm 두께의 절편을 채취하고 이를 ASTM C 114의 시험법에 따라 염화물 이온농도를 측정하였다. 측정결과를 바탕으로 지역과 수직위치에 따른 염소이온 침투의 특성을 파악하였다.

• 한국해양공학회지
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• 제21권2호
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• pp.42-49
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• 2007

It has been known that shallow-water regions, such as tidal flats, sea grass and sea weed beds have water purification capability, and they also serve as nursery grounds for many fishes. On the other hand, tidal flat areas are economically attractive sites for reclamation, to be used for developing industries. When developing shallow-water areas, we have to propose a plan to mitigate the environmental impact associated with such a development plan. However, it is difficult to estimate the affects on the ecosystem and water purification, and the literature related to this matter is insufficient. In order to evaluate the ability of coastal tidal flat and to predict the future changes, it is necessary to develop a reliable prediction technique and construction of data by using a field investigation. In this study, we carried out a numerical model test for the tidal flat ecosystem, using the pelagic system and the benthic system, simultaneously, in order to show a change in the tidal flat ecosystem. The flow of nitrogen, phosphorus and carbon has been identified as a primary consideration of marine ecosystem components, and the capability of water purification and the change of the tidal flat were predicted using this flow. In order to make a more reliable prediction, a field investigation to determine tide, current and creatures of the object coastal area has been done. The purification capability of this shallow-water region is estimated from the model results. According to the results of experiments, the tidal flat has a capability of water purification (Sink) of 11mgN/m2/day, but the other area has a load (Source) of 20mgN/m2/day. As a result, we could confirm that the tidal flat of an object coastal area plays an important role in water purification.

• 한국농공학회논문집
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• 제48권6호
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• pp.89-100
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• 2006

In order to estimate delivered nutrients load from non-point sources in the Gap stream watershed in Daejeon, a distributed watershed model SWAT2000 was used so that it could predict the impact of land management practices on water, sediments and chemicals yields in large complex watersheds with varing soils, land uses and management condition over long period of time. The SWAT2000 was applied to the Daejeon (Indong), Yudeung (Boksu) and Gap (Hoeduck) streams for TMDL (Total Maximum Daily Load) of nutrients. The observed water quality and streamflow data of the year of 2002 and 2003 were used for calibration, and those of the year 2004 and 2005 were used for validation. Simulated results were evaluated by Estimation Efficiency Analysis (COE), Regression Analysis $(R^2)$ and Relative Error (R.E.) for the nutrients amounts on the monthly and yearly basis by comparing observed load with estimated load obtained by using SWAT2000 simulations. The COE value fur T-N was ranged from 0.59 to 0.78, $R^2$ values for T-N ranged from 0.65 to 0.84, and R.E values fur T-N load ranged from 4% to 20%. COE value far T-N was ranged from 0.59 to 0.73, $R^2$ values for T-P ranged from 0.67 to 0.82, and R.E values for T-P load ranged from 3% to 25%. Estimated results of SWAT2000 simulation for 3 sites (Indong, Boksu, Hoedeok) were reasonably satisfactory. This study indicated that SWAT2000 model could be applicable to estimate the nutrients load from the Gap stream watershed in Korea.

• 한국전자통신학회논문지
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• 제7권5호
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• pp.1079-1085
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• 2012

현재 전 세계의 많은 과학자들이 지속 가능한 에너지원을 찾기 위하여 많은 노력을 하고 있지만, 태양광에너지가 궁극적인 해답이 될 것으로 받아들여지고 있다. 이러한 광 에너지는 조명용, 발열용, 통신용 등으로 사용될 수 있으며, 심지어 최근에는 광에너지로 동작하는 광자구동 모터에 대한 연구결과도 나오고 있다. 본 논문에서는 이러한 광에너지를 광섬유를 통해 전송할 수 있는 기술에 대해 이론적인 분석을 수행하였다. 특히, 한 가닥의 광섬유에 여러 개의 코어(core)가 삽입된 멀티코어(multi-core) 광섬유를 이용한 광에너지 전송의 에너지 전송량에 대해 예측해 보았다. 본 논문의 분석 결과에 따르면, 한 가닥의 멀티코어 광섬유로 약 2 kW 의 광에너지 전송이 가능할 것으로 예측되었으며, 초고압선처럼 수 cm 의 직경으로 광섬유 다발을 묶을 경우에는 10 MW 이상의 광에너지 전송이 가능할 것으로 예측되었다. 이는 도체 전력선과 비교하여 절반수준의 에너지 전송량으로 충분한 경쟁력이 있을 것으로 생각된다.

• Nutrition Research and Practice
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• 제9권1호
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• pp.37-42
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• 2015

BACKGROUND/OBJECTIVES: Red grape seeds as functional food are a good source of important bioactive components such as phenolics and antioxidants, which decrease oxidative stress that contributes to the pathogenesis of hepatotoxicity. The current study was conducted in order to evaluate the protective effect of red grape dried seeds (RGDS) on antioxidant properties, lipid metabolism, and liver and kidney functions of rats with paracetamol (750 mg/kg) induced hepatotoxicity. MATERIALS/METHODS: RGDS was added to the basal diet at 5, 10, and 20%. Thirty five adult male rats were assigned to five groups (n = 7) for a six-week feeding period; group (1) normal control, group (2) induced control, groups (3, 4, and 5) fed a diet with RGPS at different levels, 5, 10, and 20%, respectively. At the end of the feeding period, animals' blood and tissues were collected for estimation of serum lipid profile, serum liver, and kidney biomarkers. The protection was measured by detecting lipid peroxidation (LPO), glutathione (GSH), superoxide dismutase (SOD), Catalase (CAT) (in liver tissues), and liver histological examination. RESULTS: The results showed a significant (P < 0.05) decrease in levels of serum cholesterol, triglycerides, low density lipoprotein (LDL-C), and very low density lipoprotein (VLDL-C), with a significant increase in level of high density lipoprotein (HDL-C) for RGDS groups compared to induced control. Rats administered a diet containing RGDS levels produced significant (P < 0.05) hepatoprotection by decreasing the activities of liver enzymes, kidney parameters, and lipid peroxidation, while levels of GSH, SOD, and CAT were increased significantly to near the normal levels. CONCLUSION: The RGDS 20% group was more effective than others against hepatotoxicity of paracetamol, which may be attributed to RGDS total phenols and antioxidant contents, which were 1.438 mg and 1.231 mg, respectively.

• Journal of Nutrition and Health
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• 제45권4호
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• pp.303-314
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• 2012

The purpose of this study was to investigate the relationship between dietary fat intake, anthropometric data, blood lipids, C-reactive protein, and adiponectin in Korean male college students. Forty-eight subjects were divided into 2 groups based on dietary fat intake: UERF (under 30% of energy ratio for fat source), AERF (above 30% of energy ratio for fat souce). We collected dietary intake data using 24-hour dietary recall for 3 days. Anthropometric and biochemical parameters were measured by using standard methods. Segmental body composition analysis was carried out using an 8-electrode multifrequency bioelectrical impedance method of body fat estimation. There was no significant difference in anthropometric data and serum lipid profile between UERF and AERF group. Serum C-reactive protein level was significantly higher in the AERF group compared to the UERF group. Although there was no significant difference in serum adiponectin level between UERF and AERF groups, subjects had lower adiponectin levels. Correlation data show that serum adiponectin level was positively correlated with vegetable intake (p < 0.05). In addition, dietary fat intake had a positive correlation with meat (p < 0.01), whereas a negative correlation with grain (p < 0.01), vegetables (p < 0.05), and fish (p < 0.05). These results suggest that the increased fat intake of non-obese Korean male college students is associated with their increased serum C-reactive protein concentration. Therefore, proper guidelines on fat intake and nutrition education are necessary for the prevention and management of metabolic syndromes.

• 한국가스학회지
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• 제24권5호
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• pp.20-28
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• 2020

불산 누출사고 발생 시 피해영향범위 예측을 수계산, 영향평가 시뮬레이션, CFD 시뮬레이션을 활용하여서 예측하고 실제 환경영향보고서와 비교·분석하였다. 수계산은 누출원모델과 확산모델을 활용하여서 계산하였으며 영향평가 시뮬레이션은 우리나라 환경부에서 제공하는 KORA, 미국 환경부의 ALOHA, 상용화 프로그램 중 비교적 널리 사용 중인 PHAST를 사용하였고, CFD 시뮬레이션은 STAR-CMM+ 프로그램을 활용하였다. 사용자 입장에서 편리성, 신속성, 수용성, 경제성 등을 고려할 때 불산 누출사고 영향예측에 가장 적절하게 사용할 수 있는 프로그램은 ALOHA와 KORA 이었다. 아울러, 본 연구결과는 정부의 정책개발과 기업의 안전부서에서 피해영향범위 프레임워크를 선정하고 불필요한 규제, 불필요한 안전투자를 최적화하여 정부 또는 기업의 제한된 자원을 효율적으로 활용하는 데 도움이 될 것으로 기대된다.