• 한국수자원학회논문집
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• 제40권1호
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• pp.1-10
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• 2007

더 많은 수자원을 확보하기 위한 하나의 대안으로서 다목적 저수지의 홍수조절공간과 이수공간 사이에서 용량 재할당 방안을 제안하였다. 저수용량 재할당이란 기존의 저수지에 물리적 변화 없이 좀 더 많은 편익을 얻을 수 있도록 상시만수위를 조정하는 관리 기법이다. 본 연구의 목적은 홍수조절에 미치는 악영향을 최소화하면서 용수공급에 필요한 용량을 증대시킬 수 있는 저수지 용량 재할당 방법론을 개발하는 것이다. 이 방법은 다양한 빈도별 유입홍수량에 대한 홍수기 저수지 모의운영, 중요지점까지 홍수추적, 하천최대허용유량 검토, 재할당 수위에 대한 저수지 공급능력 검토 등으로 구성되어 있다. 홍수조절을 위한 저수지 모의운영 모형으로는 Rigid ROM과 HEC-5를 사용하였다. 본 연구에서 제안된 방법을 금강 유역에 적용하였다. 특히 상류의 저수지가 존재할 때와 존재하지 않을 때를 고려하여 서로 경합하는 목적들 사이의 절충을 분석하였다.

• 동의생리병리학회지
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• 제26권5호
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• pp.707-713
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• 2012

Taraxacum coreanum Nakai (TM) has been investigated for its antidiabetic activity in streptozotocin induced diabetic animals, but few studies have been conducted to evaluate its efficacy for treatment of type II diabetic mice. This study was designed to evaluate the efficacy of the water extracts of TM for the treatment of type II diabetes. Twenty four mice(C57BLKS/J Iar $-+Lepr^{db}/+Lepr^{db}$) with type II diabetes were randomly assigned either to a experimental group A (leaves extraction of TM), experimental group B(roots extraction of TM), experimental group C(leaves, roots and flowers extraction of TM) or control group. Water extracts of TM were ingested for 10 weeks. The changes of body weight, level of blood glucose, numerical change of insulin-immunoreactive cells and level of blood insulin were measured after treatment of water extracts of TM. A reduction of the blood glucose level after treatment of TM was observed in all the experimental groups. Especially, experimental C group showed significant reduction of blood glucose level compared with control group. Experimental C group induced an increase the level of blood insulin and density of insulin immunoreactive cells after treatment of TM. These results show that water extracts of TM can improve the severity in type II diabetic mice.

• 한국지반신소재학회논문집
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• 제9권3호
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• pp.87-93
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• 2010

저수지의 수위변화는 저수지 주변 강기슭 사면파괴의 주요 요인이다. 중국의 삼협댐 저수위는 홍수량 조절을 위해 145m와 175m사이에서 변화한다. 삼협댐 저수위의 정상적 운영상태에서 저수위 변동속도는 0.67m~3.0m의 범위에 있다. 마지아고 사면은 자시강의 2.1km 상류 좌측기슭에 위치한다. 자시강은 삼협지역내에 있는 양츠강의 지류이다. 2003년 저수위가 95m에서 135m로 상승한 직후, 마지아고 사면의 후면부에서 길이 20m, 폭 3~10의 균열이 발생하였다. 지금은 균열 보수 후 특별한 징후는 보이지 않고는 있으나, 이 큰 균열은 마지아고 사면의 산사태 가능성을 암시하고 있었다. 이 연구에서는 침투해석에서 얻어진 간극수압을 저수위 변동에 따른 안전율 변화를 평가하기 위해 사용되었다. 안전율 평가는 한계평형해석에 의한 사면안정해석에 의해 수행되었다. 한계평형해석에서 전단강도에 미치는 부의 간극수압 효과는 불포화 흙에 대한 프레드런드의 전단강도식을 사용하여 고려하였다. 연구결과 강기슭사면의 안전율은 저수위의 상승, 하강에 따라 감소와 증가의 경향을 보이나, 가장 위험한 상태는 저수위가 최대높이를 장기간 유지할 때인 것으로 나타났다.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2001년도 추계학술대회
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• pp.193-202
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• 2001

The individual rotten water purification tank recently discharges wastewater and sewage through the outlet without purification ability. The outlet water and affiliated water purification tank with microorganism cultivator tank cultivates microorganism and then drops the value BOD, COD of sewage and discharges the quality of water into the outlet. The blower and water pump operating continuously prompts the waste of energy and deterioration of equipment. Each room of deposition tank, foaming tank, microorganism cultivator tank is equipment with the sludge detection senses so it can detect the density of each room. The power-drive plant of the blower and water pump which ate the system cultivating the microorganism must be made as fuzzy controlization (If the sludge amount of each room become higher, the rate of operation of blower and water pump must heighten, on the contrary, in case of row sludge amount, the total handling amount and microorganism handling amount of each room of control. Tank reducing the rate of operation must be DB. At present, the blower amount in proportion to the sludge and oxygen demanding amount has to control. Each mom must be checked outlet level of the outlet, also each room must flow backward discharge materials, and must operate feed-back control until we want to be come as a below value of BOD/COD(10PPM ; KS).

• 대한안전경영과학회지
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• 제3권4호
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• pp.53-63
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• 2001

The individual rotten water purification tank recently discharges wastewater and sewage through the outlet without purification ability. The outlet water and affiliated water purification tank with microorganism cultivator tank cultivates microorganism and then drops the value BOD, COD of sewage and discharges the quality of water into the outlet. The blower and water pump operating continuously prompts the waste of energy and deterioration of equipment. Each room of deposition tank, foaming tank, microorganism cultivator tank is equipment with the sludge detection senses so it can detect the density of each room. The power-drive plant of the blower and water pump which are the system cultivating the microorganism must be made as fuzzy controlization (If the sludge amount of each room become higher, the rate of operation of blower and water pump must heighten, on the contrary, in case of row sludge amount, the total handling amount and microorganism handling amount of each room of control. Tank reducing the rate of operation must be DB. At present, the blower amount in proportion to the sludge and oxyzen demanding amount has to control. Each room mus be checked outlet level of the outlet, also each room must flow backward discharge materials, and must operate feed-back control until we want to be come as a below value of BOD/COD(10PPM ; KS).

• 한국지반신소재학회논문집
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• 제9권3호
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• pp.77-85
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• 2010

저수지의 수위변화는 저수지 주변 강기슭 사면파괴의 주요 요인이다. 중국의 삼협댐 저수위는 홍수량 조절을 위해 145m와 175m사이에서 변화한다. 삼협댐 저수위의 정상적 운영상태에서 저수위 변동속도는 0.67m~3.0m의 범위에 있다. 마지아고 사면은 자시강의 2.1km 상류 좌측기슭에 위치한다. 자시강은 삼협지역내에 있는 양츠강의 지류이다. 2003년 저수위가 95m에서 135m로 상승한 직후, 마지아고 사면의 후면부에서 길이 20m, 폭 3~10의 균열이 발생하였다. 지금은 균열 보수 후 특별한 징후는 보이지 않고는 있으나, 이 큰 균열은 마지아고 사면의 산사태 가능성을 암시하고 있었다. 이 연구에서는 저수위 변화와 관련하여 사면내에서 간극수압의 변화를 모의하기 위해 불포화 및 포화 침투해석이 수행되었다. 얻어진 간극수압은 저수위에 따른 안전율 변화를 평가하기 위해 사용되었다. 연구결과 침윤선은 저수위 변화보다 상당히 지연된 반응을 보였고, 저수위의 상승-하강과정에서 침윤선은 각각 요면과 철면의 형상을 나타내었다. 또한 저수위의 변동은 사면의 전면부에만 영향을 미치고 있었고 후면부에는 영향을 미치지 않았다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.638-640
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• 2004

The gas stripper system of a nuclear power plant provides gas-free water to a reactor and a turbine system. The gas tripper unit has two control systems to regulate pressure and level independently. Because the level and the pressure interact as a control disturbance each other, continuous operation of the system is difficult. In this paper, We describe the controllability evaluation of the gas stripper system and the results of the optimally tuned control gains.

• Journal of Nutrition and Health
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• 제29권9호
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• pp.934-942
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• 1996

This study was performed to investigate the influence of dietary fibers on the serum lipid level and bowel function in aged rats. Fiber sources of experimental diets were made from mugwort(M), butterbur(B), apple(A), sea mustard(S) by drying and milling. Each of fiber sources was mixed into the diet at the level of 5, 15% of diet. Sprague-Dawley strain, 13 month old male rats were divided into 9 groups by randomized complete block design : C, M5, B5, A5, S5, M15, B15, A15, S15. The animals were fed ad libitum each of experimental diets for 4 weeks. Control group showed lower food intake compare to the other groups. There were no significant difference between 5% groups and 15% groups in food intake. Fecal weight, dry fecal weight and fecal water content of control group were significantly lower than those of experimental groups, and fecal water content was increased by increasing level of dietary fibber. Apple group showed the lowest values, sea mustard group showed the highest. The shorter transit time was observed in the group of higher intake of dietary fiber. At the same level of dietary fiber, transit time of sea mustard group was shorter than the other groups. With increasing age, serum triglycerides, total cholesterol were increased and HDL-cholesterol was decreased. Fiber fed groups showed lower serum TG, TC and higher HDL-c level compare to the control group. Absorption rates of calcium, magnesium and phosphorus was tend to be lower in the group fed dietary fiber sources than control group. Mucosa weight and maltase activity in the small intestine were decreased by increasing age. As intake of dietary fiber increaed, mucosa weight in the small intestine was not different but maltase activity was decreased.

• 한국도로학회논문집
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• 제15권1호
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• pp.47-56
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• 2013

PURPOSES: This study is to evaluate a ground water level effect on frost heaving in road pavements. METHODS: The effects of water table on frost heaving in pavement systems were evaluated from the mechanical analysis using FROST program. The input parameters and boundary conditions were determined by considering climates, pavement sections, and material properties specially subgrade soil types in Korea. RESULTS: When the water table located above the freezing depth, amount of frost heaving caused by freezing the water in pavement itself was big enough to damage in pavement system, although pavement system consists of fully non-frost-susceptible materials with sufficient thickness of anti-freezing layer. The amount of frost heaving was decreased rapidly with increasing the distance between the water table and freezing depth. CONCLUSIONS: It was concluded that there is no engineering problems related with frost heaving in practical sense when the distance between freezing depth and water table is over 1.5m for having subgrade soils less than 50% of #200 sieve passing to meet specification on quality control in Korea.

• 한국물환경학회지
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• 제26권5호
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• pp.768-774
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• 2010

This study was conducted to provide a technical solution to treat effectively perchlorate from inorganic wastewater of zinc smelting. Despite an inhibition dissolved inorganic substances in the wastewater discharged from zinc smelting has demonstrated with the activity of microbes, biological treatment technology could reduce perchlorate to a satisfactory level under such stressful conditions. It was found that either conductivity or $SO{_4}^{2-}$ concentration of the wastewater was able to be used as the adequate index and the values were $2,450{\mu}S/cm$ and 1,200 ppm respectively. When $SO{_4}^{2-}$ increased from 0 to 16,000 ppm (conductivity : $428{\rightarrow}24,800{\mu}S/cm$), perchlorate biodegradation rate was reduced due to 1/10 times from 0.0365 to 0.0033/h, however, most of perchlorate was removed under the condition of hydraulic retention time (HRT) at 0.5day and mixed liquor volatile suspended solid (MLVSS) at 2,000 ~ 3,000 ppm.