• 환경영향평가
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• 제19권3호
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• pp.247-257
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• 2010

Watershed runoff and turbid water dynamics were simulated in the Youngju Dam, being constructed. The runoff flow and suspended solids were simulated and then thermal stratification and turbid water current in the reservoir were predicted by HSPF and CE-QUAL-W2 model, respectively. Considering selective withdrawal, we hypothesized 3 withdrawal types from the dam, i.e. surface layer, middle layer and the lowest layer. The maximum concentration of SS was 400mg/L in reservoir and it was decreased by the withdrawal. The inflowed turbid water fell to 30 NTU after 12 days regardless of the withdrawal types, but the surface layer withdrawal was a better type at turbid water discharge than the others. In current environmental impact assessment(EIA), we concluded that runoff and reservoir water quality predicted by HSPF and CE-QUAL-W2 was desirable, and appropriate parameters were selected by continous monitoring after EIA.

• 환경영향평가
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• 제21권5호
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• pp.715-724
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• 2012

In this study, we simulated water temperature in the downstream according to withdrawal types of dam using EFDC model. Three scenarios were assumed as water was released from the surface layer, the middle layer, and the bottom layer at intervals of 10m depth. In case of the surface layer withdrawal, the water temperature rose from March and lowered gradually after it reached a peak in August. The middle and the bottom layers effluence temperatures were lower than the surface layer temperature by maximum $15.9^{\circ}C$(in July), but after September, temperature inversion appeared. It was advantageous for the surface layer withdrawal to decrease cold damage and fog in downstream area and was possible to the middle and the bottom layers withdrawal from August to September. However, the reliability of model should be improved by accumulating the real-time information of water temperature.

• 한국물환경학회지
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• 제27권6호
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• pp.743-753
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• 2011

One of the most important water management issues of Soyang Reservoir, located in North Han River in Korea, is a long term discharge of turbid water to downstream during flood season. Installation of a selective withdrawal structure (SWS) is planned by the reservoir management institute as a control measure of outflow water quality and associated negative impacts on downstream water use and ecosystem. The objective of the study was to explore the effectiveness of the SWS on the control of outflow turbidity under two different hydrological years; one for normal flood year and another for extreme flood year. A two-dimensional (2D), laterally averaged hydrodynamic and water quality model (CE-QUAL-W2) was set up and calibrated for the reservoir and used to evaluate the performance of the proposed SWS. The results revealed that the SWS can be an effective method when the ${\Theta}$ value, the ratio between the amount of turbid water that containing suspended sediment (SS) greater than 25 mg/L and the total storage of the reservoir, is 0.59 during the normal flood year. However, the effectiveness of the SWS could be marginal or negative in the extreme flood year when ${\Theta}$ was 0.83. The results imply that the SWS is an effective alternative for the control of turbid water for moderate flood events, but not a sufficient measure for large flood events that are expected to happen more often in the future because of climate change.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.400-401
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• 2005

• 생태와환경
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• 제37권4호통권109호
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• pp.423-430
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• 2004

본 연구는 선택 취수하는 저수지에서 장마 전후에 탁수의 거동을 파악하고자 하였다. 강수량은 11월-5월에 적었고, 6월-10월에 풍부하여 대비가 되었다. 수문에 의한 방류는 선행 강수량과 유입량이 각각 50mm, $80\;m^3^s{-1}$이상일 때 조작되었고, 그 외 기간은 대부분 취수탑을 통해 배출되었다. 하류부를 중심으로 비교할 때, 장마 전후 수중 탁도 차이는 평균값이 29.9NTU로서 장마 후에 크게 증가하였다. 탁수에 포함된 입자 크기의 범위는 0.435-$482.9\;{mu}m$이었고, 전 정점에서 clay성분의 미세립자로 갈수록 크기 분포가 더욱 조밀하였을 뿐만 아니라 상대적으로 차지하는 비율도 높았다. 탁수의 입자 분포에서 clay는 94.4-98.9%, silt는 1.1-5.6% 범위로서 총 입자수의 대부분을 차지하였다. 입자 분포에 의한 탁수의 흐름을 분석한 결과, 저수지의 하류부에서 총입자수는 저층에서 표층으로 갈수록 선형적인 증가가 뚜렷하였다. 이것은 저수지의 수리학적 환경과 밀접한 관련성이 있었고, 선택취수탑과 수문을 통한 방류에 의한 영향이 큰 것으로 추정되었다. 하천으로부터 유입된 탁수는 중류부에서 침강되다가 하류부에서 재부유하는 현상이 발생함으로서 표층-중층을 통한 탁수 이동이 현저하였다. 따라서, 향후 저수지 수질관리 측면에서 이에 대한 육수학적 영향을 규명할 필요성을 제시하고자 한다.

• 물과 미래
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• 제25권2호
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• pp.99-110
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• 1992

담수화호에서는 온도 및 염도차에 의하여 성층류가 발생하며 수심이 깊은 담수화호의 경우 그 형상이 더욱 뚜렷하다. 본 연구는 깊은 담수화호를 대상으로 내부환경면이 잘 발달된 이층류에 있어서 저층배수관의 유출수 염분농도를 실험을 통하여 규명하였다. 실험에 이용된 저층배수관은 세가지 유형으로 유입층과 배수관의 유출수 염분농도차를 무차원으로 수식화 하였고 유입층의 상층부 흐름이 순간적으로 배수되는 밀도층의 한계조건을 밀도 Froude수와 배수관의 직경 및 수심의 함수로 방정식을 유도하였다.

• The Korean Journal of Pain
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• 제20권2호
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• pp.92-99
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• 2007

Background: A correlation between a T-type voltage activated calcium channel (VACC) and pain mechanism has not yet been established. The purpose of this study is to find out the effect of ethosuximide and mibefradil, representative selective T-type VACC blockers on postoperative pain using an incisional pain model of rats. Methods: After performing a plantar incision, rats were stabilized on plastic mesh for 2 hours. Then, the rats were injected with ethosuximide or mibefradil, intraperitoneally and intrathecally. The level of withdrawal threshold to the von Frey filament near the incision site was determined and the dose response curves were obtained. Results: After an intraperitoneal ethosuximide or mibefradil injection, the dose-response curve showed a dose-dependent increase of the threshold in a withdrawal reaction. After an intrathecal injection of ethosuximide, the threshold of a withdrawal reaction to mechanical stimulation increased and the increase was dose-dependent. After an intrathecal injection of mibefradil, no change occurred in either the threshold of a withdrawal reaction to mechanical stimulation or a dose-response curve. Conclusions: The T-type VACC blockers in a rat model of postoperative pain showed the antihyperalgesic effect. This effect might be due to blockade of T-type VACC, which was distributed in the peripheral nociceptors or at the supraspinal level. Further studies of the effect of T-type VACC on a pain transmission mechanism at the spinal cord level would be needed.

• Journal of Chest Surgery
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• 제33권2호
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• pp.132-138
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• 2000

Background: Inhaled nitric oxide therapy causes selective pulmonary vasodilation in congenital heart diseases with pulmonary hypertension. However discontinuation of inhaled nitric oxide therapy may be complicated by abrupt life-threatening rebound pulmonary hypertension(RPH) The purpose of this study was to prevent by comparing group I(without RPH n=13) and group II(with RPH n=6) to determine the risk factors involved inthe development of the RPH. Material and Method: Between Januarty 6, 1998 and April 14, 1999. we studied 19 consecutive children who were treated with inhaled nitric oxide for clinically significant pulmonary hypertension after an open heart surgery for congenital heart disease. the ratio of males and females was 12:7 ranging in age from 10 days to 6040 days(16 years) To identify the effects of nitric oxide between two groups we measured heart rate mean and systolic pulmonary arterial pressure mean and systolic systemic arterial pressure central venous pressure pH paO2/FiO2 and O2 saturation before and after the initiation and just before the withdrawal of the inhaled nitric oxide. result: In 6 of 19 patients(32%) withdrawal of inhaled nitric oxide caused RPH. In the two groups inhaled nitrix oxide decreased in pulmonary arterial pressure(PAP) without decreasing the systemic arterial pressure(SAP) and increased PaO2/FiO2 Compared with patients who had no RPH(group I) patients who had RPH(group II) were older in age (1204$\pm$1688 versus 546$\pm$1654 days p<0.05) received less nitric oxide therapy(34$\pm$18 versus 67$\pm$46 hours p<0.05) has shorter weaning process(5$\pm$3 versus 15一13 hours p<0.05) and received lowerconcentration of initial nitric oxide supply(11$\pm$8 versus 17$\pm$8 ppm p>0.05) and lower concentration just before the withdrawal nitric oxide(4.2$\pm$2.6 versus 5.6$\pm$2.6 ppm, p>0.05) Conclusion : We speculate that older age shorter of nitric oxide therapy shorter weaning process are the risk factors of RPH.

• Journal of Ginseng Research
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• 제38권4호
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• pp.256-263
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• 2014

Background: Korean Red Ginseng (KRG) is known to have antianxiety properties. This study was conducted to investigate the anxiolytic effects of KRG extract (KRGE) during ethanol withdrawal (EW) and the involvement of the mesoamygdaloid dopamine (DA) system in it. Methods: Rats were treated with 3 g/kg/d of ethanol for 28 d, and subjected to 3 d of withdrawal. During EW, KRGE (20 mg/kg/d or 60 mg/kg/d, p.o.) was given to rats once/d for 3 d. Thirty min after the final dose of KRGE, anxiety-like behavior was evaluated in an elevated plus maze (EPM), and plasma corticosterone (CORT) levels were determined by a radioimmunoassay (RIA). In addition, concentrations of DA and 3,4-dihydroxyphenylacetic acid (DOPAC) in the central nucleus of the amygdala (CeA) were also measured by high performance liquid chromatography (HPLC). Results: The EPM test and RIA revealed KRGE inhibited anxiety-like behavior and the over secretion of plasma CORT during EW. Furthermore, the behavioral effect was blocked by a selective DA D2 receptor (D2R) antagonist (eticlopride) but not by a selective DA D1 receptor (D1R) antagonist (SCH23390). HPLC analyses showed KRGE reversed EW-induced decreases of DA and DOPAC in a dose-dependent way. Additionally, Western blotting and real-time polymerase chain reaction (PCR) assays showed that KRGE prevented the EW-induced reductions in tyrosine hydroxylase (TH) protein expression in the CeA and TH mRNA expression in the ventral tegmental area (VTA). Conclusion: These results suggest that KRGE has anxiolytic effects during EW by improving the mesoamygdaloid DA system.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.556-559
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• 2007

고탁수 장기화 문제를 해결하기 위한 방법으로는 고탁수층을 선택취수하여 우선 배제함으로써 하류하천의 고탁수 발생일수를 최소화하는 방법이 있는데, 이와 같은 선택적 취수기법은 저수지 운영에 있어서 고탁수층을 우선 배제한 후 홍수기 이후에 저수지내로 유입되는 청수를 담수하여 호소 내 탁도 저감 효과를 얻을 수 있다. 본 연구에서는 선택취수 시 성층수괴의 동수역학적 변화를 분석하기 위하여 국내에서 처음으로 Two-tank 기법을 이용하여 성층구조를 구현해 내었는데, 소금물의 밀도변화를 이용하여 수심 1m의 성층수조를 만들었고, 밀도경사가 상이한 성층구조에서 취수조건을 변화시키면서 비교란 유속계인 PIV 시스템을 이용해 유속의 흐름을 Vector와 Contour로 분석하였다. 선택취수에 대한 흐름의 동수역학적 분석결과 취수유량보다는 밀도성층경사 변화에 더 민감한 반응을 보였다. 취수유량을 줄이거나 밀도성층경사를 급하게 했을 때에는 선택취수 영역(withdrawal zone)의 수직방향 폭은 줄어드는 반면, X축으로의 영향범위는 증가함을 나타냈다. 취수유량을 증가시키거나 성층밀도경사를 완만히 했을 땐 선택취수 영역(withdrawal zone)의 수직방향 폭은 증가하였고 X축으로의 영향범위는 축소됨을 나타내었다. 이 결과는 Richardson 수로도 판단되어지는데, Richardson 수가 증가하면 유속에 비해 상대적으로 밀도성층경사가 크다는 것인데 이럴 경우 선택취수 영역(withdrawal zone)의 수직방향 폭 최대가 되고 선택취수 영역(withdrawal zone)의 수직방향 폭은 최소가 된다. 선택취수 영역(withdrawal zone)의 수직방향 폭이 최소가 되면 취수구 직경 D의 1.8배의 값을 가지고 Richradson 수가 최소가 되더라도 취수구 직경 D의 3.3배를 벗어나지 않는다는 결과를 도출할 수 있었다.링 목적으로 사용될 수 있다. 본 연구에서 개발한 영상수위계는 한강홍수통제소 관할의 전류, 청담대교 등 4개소 낙동강 홍수통제소 2개소, 지자체 등에 적용되었으며, 적용 결과 비교적 안정적이면서 정확하게 수위를 측정하는 것으로 나타났다. 한편 기존 CCD 카메라 이외에 CCTV를 이용한 영상수위계를 개발하여 영상의 화질 개선뿐 아니라 하천화상 감시 기능을 강화하였다.소류의 섭취율은 높았다. 집단간의 상관도를 보면 교육별로 김치, 장아찌, 콩이 각각 p>0.5 수준에서 유의한 차가 없었고, 나머지는 유의한 차가 있었다. 연령별로는 멸치가 유의한 차가 없었고(p>0.5), 수입별로는 콩이 유의한 차가 없었다(p>0.5). 4. 영양지식(營養知識) 검토 가정생활(家庭生活)에 필요(必要)한 일반적(一般的)인 영양지식(營養知識)은 대체적으로 낮은 편이었다. 어린이 영양, 편식의 해로움, 비만증의 해로움, 임신부 그리고 수유부 영양에 대하여는 일반적으로 알고 있다고 하였으며, 그다음으로 이유기 영양, 어린이 발육에 필요한 식품, 식품과 영양소와의 관계, 우유의 성분, 노인영양에 대하여 잘 알고 있는 비율이 낮았으며, 인체의 영양소, 식단작성여부, 간식의 이론, 식품감별법에 대하여는 가장 낮은 비율을 나타냈다. 각 영양지식은 교육정도가 높을수록 영양지식이 높았고, 교육별 집단간의 유의한 차가 나타났다. (0.001