• 한국항만학회지
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• 제5권2호
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• pp.65-75
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• 1991

Tidal current and water level change in coastal waters are formulated in terms of mathematical models. A systematic discussion of the derivation of a set of governing equations, expressing conservation of mass and momentum is presented. A simplification is introduced by integrating all variables and equations over the total water depth, the Solution of the formulated problem is achieved by using the finite difference method(FDM). The applied study area is taken from Mokpo harbor and its adjacent coastal water which have significant hydrographical changes due to the construction of the estuary barrage and land reclamation work of estuary barren. Some comparisons with the observed current and water level changes the numerical solutions are found to be considerably fit well for the recent coastal water motion.

• 자원환경지질
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• 제45권5호
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• pp.525-533
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• 2012

겨울철동안 쌓여 봄에 놓은 눈 녹은 물(snowmelt), 즉 융설의 유출은 북반구 및 산간지역에서 매우 중요한 것으로 여겨지고 있다. 이러한 지역에서 융설로 인한 유동 및 이온의 이동에 대한 이해는 매우 중요하며 전세계적으로 꾸준하게 연구되고 있다. Lee et al. (2008a)와 Lee et al. (2008b)연구에서는 대기로부터 수송된 이온 및 오염원이 융설에 의해 눈속을 이동하는 것을 모사하기 위한 Mobile-Immobile water Model (MIM)을 개발하였다. 이 연구에 사용된 모델을 검증하기 위해서 물질수지계산(mass balance calculation) 및 해석해(analytical solution)를 이용한 모델결과와의 비교를 수행하였다. 일정시간동안 눈 속에서의 물질의 질량변화는 눈 표면에서 들어온 물질과 눈 기저부에서 빠져나간 물질의 질량 차이와 같아야한다는 사실을 이용하여 물질수지를 계산하였다. 파면(wave front)의 이동속도 및 기존문헌에서 알려진 해석 해를 이용하여 모델결과와의 비교도 시도하였다. 모델의 물질수지계산결과 질량 차이가 거의 발생하지 않았으며 모델결과와 해석해와의 비교 역시 두 결과가 거의 일치하였다.

• Geomechanics and Engineering
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• 제18권1호
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• pp.1-9
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• 2019

In this study, both 2D and 3D failure shapes of rock mass above the water-filled cavity are put forward when the surrounding rock mass cannot bear the pressure caused by the water-filled cavity. Based on the analytical expressions derived by kinematic approach, the profiles of active and passive failure patterns are plotted. The sensitivity analysis is conducted to explore the influences of different rock parameters on the failure profiles. During the excavation of the deep tunnels above the karst cavity, the water table always changes because of progressive failure of cavity roof. Therefore, it is meaningful to discuss the effects of varying water level on the failure patterns of horizontal rock layers. The changing laws of the scope of the failure pattern obtained in this work show good consistency with the fact, which could be used to provide a guide in engineering.

• 지구물리와물리탐사
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• 제7권1호
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• pp.25-32
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• 2004

We have carried out laboratory measurements of P-wave velocity and deformation strain during $CO_2$ injection into a porous sandstone sample, in dry and water-saturated conditions. The rock sample was cylindrical, with the axis normal to the bedding plane, and fluid injection was performed from one end. Using a piezoelectric transducer array system, we mapped fluid movement during injection of distilled water into dry sandstone, and of gaseous, liquid, and supercritical $CO_2$ into a water-saturated sample. The velocity changes caused by water injection ranged from $5.61\;to\;7.52\%$. The velocity changes caused by $CO_2$ injection are typically about $-6\%$, and about $-10\%$ for injection of supercritical $CO_2$, Such changes in velocity show that the seismic method may be useful in mapping $CO_2$ movement in the subsurface. Strain normal to the bedding plane was greater than strain parallel to the bedding plane during $CO_2$ injection; injection of supercritical $CO_2$ showed a particularly strong effect. Strain changes suggest the possibility of monitoring rock mass deformation by using borehole tiltmeters at geological sequestration sites. We also found differences associated with $CO_2$ phases in velocity and strain changes during injection.

• 한국응용과학기술학회지
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• 제36권4호
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• pp.1164-1171
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• 2019

Dietary supplements derived from natural sources are an essential factor in optimizing athletic performance. It has been proposed that the extract of Momordica charantia (M. charantia) that is known as a bitter melon can be potentially used as a novel supplement for health promotion. This pilot study aimed to examine the effects of the M. charantia extract when administered in the form of a sports drink, and we evaluated changes in body composition and metabolic factors in tennis players after 4-week consumption of the extract. Eight male college tennis players were instructed to consume an M. charantia extract 6 times per day (3 in the morning and 3 in the afternoon, and the total daily intake was 600 ml). Collected data were analyzed using paired t-tests to examine the changes over time after consumption of the M. charantia extract. The results revealed a significant increase in the trunk muscle mass, basal metabolic rate, and daily calorie intake (p < 0.05). Levels of protein, minerals, and total body water showed an increased tendency (not statistically significant), whereas intracellular water and extracellular water showed a decreased trend. Furthermore, fat-free mass, skeletal muscle mass, and muscle mass showed an increased tendency. In conclusion, consumption of the M. charantia extract caused an increase in parameters related to protein, muscle mass, and metabolism. It seems that follow-up studies related to fatigue, inflammation, and stress hormones related to the M. charantia extract consumption would be needed.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1199-1202
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• 2005

Inside of working PDP, there exist highly reactive conditions in the gap between two glass panels. MgO film and phosphor have been investigated as a function of discharge, also phosphor and sealing frits have been investigated as a function of temperature. Changes of impurity generation of MgO, phosphor and sealing fits were measured by using x-ray photoelectron spectroscopy (XPS) and quadropole mass spectroscopy (XPS) and quadropole mass spectrometer (QMS). Impurities such as CO, $CO_2$, OH and $H_2O$ were increased during discharge and heating treatment. Gaseous impurities such as carbon compounds and water deteriorated the characteristics of PDP operation during of lifetime. So metal is used to remove the impurities of phosphor and sealing frits during hearting, the result that the quantity of the impurities such as carbon monoxide and water was reduced.

• 동의신경정신과학회지
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• 제3권1호
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• pp.25-45
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• 1992

Many phychiatrists have reported that the change of serotonin concentration would cause mental disorder and affect the pathological conditions such as schizophrenia, depression and eating behabior. The end product of serotonin metabolism was excreted as 5-HIAA in urine. Serum lipids, according to the report, were concerned with obesity, said it was. This study aims to observe the changes of plasma serotonin, urinary 5-HIAA and serum lipids, making use of Fat Cell Mass rate of 27 normal persons and 42 psychosomatic patients. For this, I also observed the change of serotonin, 5-HIAA and lipids of the psychosomatic patients by the use of 3 kinds of herbs as treatment medication on the basis of physical symptoms and the results were obtained as follows; 1. Urinary 5-HIAA is correlated with the body water rate(r=0.381), while reversely correlated with the Fat Cell Mass rate(r=-0.330). 2. Compared the control group with the patients group for the serum lipids value, they showed the significant results ; $146.4{\pm}5.71$ mg/dl and $166.9{\pm}6.56$ mg/dl in the total cholestrol value over- weights, $471.2{\pm}42.99$ mg/dl in the total lipid value, and $158.1{\pm}6.50$ mg/dl and $181.1{\pm}6.30$ mg/dl in the phospholipid of the obesity, respectively. 3. With comparison of each group to other group to the others for Fat Cell Mass rate, the total cholesterol showed the significant differences when the Fat Cell Mass rate was 20% or more, HDL-cholesterol value when 30% or more, and triglyceride when 30% or more, respectively. 4. there was significant variations in the relations between Fat Cell Mass rate and body water, which body mass index was increased as the body water was decreased. 5. Fat Cell Mass rate was correlated with Cholesterol(r = 0.420), triglyceride (r = 0.443), and $\beta$-lipoprotein(r = 0.450) of serum lipids, while reversely correlated with HDL -Cholesterol(r = -0.354) and urinary 5- HIAA had the correlation coefficient of -0.330. 6. What related with body water rate urinary 5-HIAA (r = 0.381) and $\beta$-lipoprotein(r = -0.405). 7. there were significant changes in the total cholesterol value and HDL-Cholesterol Value of serum lipids after dose of Ondamtang, significant increase in the 5-HIAA value after dose of Samulansintang, and significant devrease in the Trigylceride value of serum lipids after dose of Shihosogansan. As a result, it was seen that there was direct correlations among the Fat Cell Mass, urinary 5-HIAA, and serum lipids and stress from the mental conditions was not correlated directly to Serotonin, 5-HIAA, and serum lipids. I would like to conclude, therefore, that the detailed study should be performed on the function of serotonin of hypothalamus.

• 한국어병학회지
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• 제26권3호
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• pp.173-183
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• 2013

2012년 7월에서 9월초까지 경상남도 연안의 해상 가두리 양식장에서 사육중인 조피볼락의 대량폐사가 발생하였으며, 피해량은 1,802,000마리로 집계되었다. 폐사 해역의 수온은 최대 $28.4^{\circ}C$까지 상승하였으며, 일간 수온변화의 폭은 최대 $6.5^{\circ}C$로 급격한 상승과 반복적인 변화가 확인되었다. 49개 어업권 194마리를 대상으로 생물학적 질병을 조사한 결과, 일부 양식장의 조피볼락에서 참돔이리도바이러스(red seabream iridovirus, RSIV), Vibrio sp.와 Vibrio spp. 또는 Microcotyle sp. 등의 주요 병원체가 확인되었다. 대량폐사의 주요 원인은 고수온과 동반하여 나타나는 반복적인 일간 수온변화, 그리고 생물학적 질병이 폐사의 증가에 영향을 미친 것으로 판단된다.

• 한국방재학회 논문집
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• 제10권5호
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• pp.109-116
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• 2010

강우로 인한 침투 및 지하수위 상승은 산사태나 사면 활동의 주요 원인이다. 이러한 경우 사면의 안전율을 확보하기 위하여 사면 경사를 완만하게 하거나, 보강재를 이용하여 저항력을 높여주는 공법이 사용된다. Mass Nail 공법은 Nail 보강공과 경사면 배수공, 표면 녹화공을 동시에 적용할 수 있는 환경 친화적인 경사면 보강 공법이다. 본 연구에서는 Mass Nail로 보강된 사면의 보강효과를 확인하기 위해 강우로 인한 사면의 함수비 변화를 고려하여 실내 모형 실험을 수행하였다. 그 결과, 무보강 사면에 대한 Mass Nail 보강 사면의 안전율은 약 1.4~2.3배 증가하였고, 함수비를 10%에서 22%로 증가 할 경우 무보강 사면에서 최대 응력은 12%~24%, 평균 18% 감소하였고, Mass Nail 경사면 보강법을 적용한 사면은 4%~23%, 평균 14% 감소함을 알 수 있었다.

• Journal of the korean society of oceanography
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• 제31권4호
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• pp.164-172
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• 1996

CREAMS (Circulation Research of the East Asian Marginal Seas) Expeditions have provided a rare opportunity to carry out precise measurements of salinity, temperature and chemical tracers extensively in all major basins of the East Sea (Japan Sea) in 1993-1996 for the first time in more than 60 years since Uda's investigation (Uda, 1934). Studies revealed unequivocal evidence that the East Sea Proper Water (ESPW), previously known as a single homogeneous water mass, is indeed made of several distinct water masses. CREAMS data further confirmed the earlier observations of Gamo et al. (1986) that properties in Deep Waters in the East Sea have been changing during at least the last 25 years. There is evidence, especially from the analysis of the DO profile, that these changes may result from a major change in the mode of deep water formation: from bottom water formation in the past to intermediate/deep water formation in recent years. The causes for these changes are not clear at the present time, but nay include natural variation and may also reflect recent global changes in regional scale. A moving-boundary box model is presented to describe current observations, predicting the turnover time of the total deep and bottom waters to the cold surface waters to be ${\sim}$80 years in 1996.