• 한국환경과학회지
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• 제7권6호
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• pp.833-843
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• 1998

It is noted that the red tides and the oxygen-deficient water mass are extensively developed in Masan Bay during summer. The nutrients mass balance was calculated in Masan Bay, using the three-dimensional numerical hydrodynamic model and the material cycle model. The material cycle model was calibrated with the data obtained on the field of the study area in June 1993. The nutrients mass balance calculated by the combination of the residual currents and material cycle model results showed nutrients of surface and middle levels to be transported from the inner part to the outer part of Masan Bay, and nutrients of bottom level to be transported from outer part to inner part of Masan Bay. The uptake rate of DIN in the box A1(surface level of inner part) was found to be 337. 5mg/$m^3$ㆍday, the largest value in all 9 boxes and that of DIP was found to be 18.6mg/$m^3$ㆍday in box A1, and the regeneration rate of DIN was found to be 78.2mg/$m^3$ㆍday in the box A3(bottom level of inner part), and that of DIP was found to be 18.6mg/$m^3$ㆍday in box A1. The regenerations of DIN and DIP in the water column of the entire Bay were found to be 7.66ton/day and 760kg/day, respectively. And the releases of DIN and DIP from the sediments of the entire Bay were found to be 2.86ton/day and 634kg/day, respectively. The regeneration rate was 2.5 times as high as the release rate in DIN, and 1.2 times in DIP. The results of mass balance calculation showed not only the nutrients released from the sediments but the nutrients regenerated in water column to be important in the control and management of water quality in Masan Bay.

• 해양환경안전학회지
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• 제24권5호
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• pp.545-552
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• 2018

본 연구에서는 갈대군락의 영양염 물질수지 모델 구축을 위한 기초연구로서, 갈대군락 Mesocosm 실험을 통해 수층-갈대(뿌리, 잎, 줄기)-토양의 영양염(DIN, DIP) 농도의 춘계 및 하계 모니터링 결과를 이용하여 물질수지를 산정하였으며, 결과는 다음과 같다. 1) 갈대의 생체량은 춘계에는 지하경이 지상경에 비해 약 6.3~9.7 % 높으며, 하계에는 지상경이 지하경에 비해 약 19.2~21.2 % 높게 나타났으며, 갈대의 성장속도는 Mesocosm Tank A가 Mesocosm Tank D에 비해 지상경과 지하경 모두 2~3배 정도 빠르게 나타났다. 2) Mesocosm Tank에서의 갈대의 영양염(DIN, DIP) 농도는 춘계와 하계 모두 각각 2~3 %로 차이가 적었다. 3) Mesocosm Tank별 생체량의 차이는 최대 23 %로 나타나지만, 갈대가 흡수하는 영양염의 농도는 최대 3 % 정도로 차이가 적었다.

• 한국환경과학회지
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• 제20권7호
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• pp.919-927
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• 2011

A ecosystem model was applied for understanding of circulation process of state variables in marine ecosystem. A mass balance was conducted by calculating the physical process. The sensitivity analysis was conducted to know which coefficient is the most effective factor to the state variables in the model. The results of the mass balance indicate that the primary production was 58.6 ton C/day in the case of mass flux. DIN and DIP in nutrient ingestion of phytoplankton were each 7.9 ton N/day, 1.1 ton P/day. POC and DOC in mineralization of organic matter were each 10.8 ton C/day, 40.6 ton C/day. The results of sensitivity analysis showed that the maximum growth rate of phytoplankton was the most important factor for overall state variables. In the case of nutrients, Half saturation constant of DIN, and mineralization rate of DOM for COD were important factor.

• 한국식품영양학회지
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• 제14권2호
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• pp.106-112
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• 2001

The purpose of this study was to investigate to the effect of regular exercise on nutrients intakes and energy balance related to food habit and nutrient knowledge of college women. This study was conducted from May to June in 2000. One hundred and forty female students made their three day dietary records by 24-hr recall method and one day activity record. The questionaires were designed to fine out food habit and nutrition knowledge status. The height. weight and blood pressure were measured and also body fat mass and lean body mass measurements were performed. The results obtained are summerized as follows. Average height and weight of E(exercise) group were found to be increased than those of NE(non-exercise) group. The percent of body fat and body fat mass(kg) in E group were slightly lower than those of NE group. Calorie intake of NE group was 1,664kca1 per day. This was composed of carbohydrate 60%kcal. protein 14%local and fat 24%local. Calorie, calcium, iron, vitamin A, vitamin B$_2$ and niacin intakes of NE group were lower than those of RDA and calorie intake of E group was 2.313kca1 per day. This was composed of carbohydrate 54%, protein 13% and fat 31%. Other nutrients such as iron, vitamin A, niacin and vitamin C were lower than those of RDA. Daily energy expenditure and physical activity of E group were 2,397.6$\pm$49.2kca1; 1,035.7 $\pm$36.5kcal, respectively and it was higher than those of NE group.

• 한국수산과학회지
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• 제47권6호
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• pp.1026-1036
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• 2014

Real-time monitoring for environmental factors (temperature, salinity, chlorophyll-a, etc.) and fugacity of carbon dioxide ($fCO_2$) was conducted at an oyster Crassostrea gigas farm in Goseong Bay, south coast of Korea during 2-4th of November, 2011. Surface temperature and salinity were ranged from $17.9-18.7^{\circ}C$ and 32.7-33.8, respectively, with daily and inter-daily variations due to tidal currents. Surface $fCO_2$ showed a range of $390-510{\mu}atm$ and was higher than air $CO_2$ during the study period. Surface temperature, salinity and $fCO_2$ are showed significant correlations with chl.-a and nutrients, respectively. It means when chl.-a value is high in surface water of the oyster farm, active biological production consume $CO_2$ and nutrients from environments and produce oxygen, suggesting a tight feedback between biological processes and environmental reaction. Thus, factors affecting the surface $fCO_2$ were evaluated using a simple mass balance. Temperature and biological productions by phytoplankton are the main factors for $CO_2$ drawdown from afternoon to early night, while biological respiration increases seawater $CO_2$ at night. Air-sea exchange fraction acts as a $CO_2$ decreasing gear during the study period and is much effective when the wind speed is higher than $2-3m\;s^{-1}$. Future studies about organic carbon and biological production/respiration are required for evaluating the roles of oyster farms on carbon sink and coastal carbon cycle.

• Nutritional Sciences
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• 제4권1호
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• pp.34-38
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• 2001

The purpose of this study was to compare the energy expenditure of normal-weight and overweight Korean middle-aged women (40-60 yr). Middle-aged oveweight ($BMI\;{\geq}\;25$, n= 20) and normal-weight women were ($BMI\;{\leq}\;23$, n = 20) were recruited in Seoul. Anthropometric measurements, body composition, energy intake, daily activity time, and energy costs of some daily activities were measured. Energy expenditure at rest and while reading the newspaper, washing dishes, mopping the floor, and walking on a treadmill at 1.0, 2.0, 3.5mph were measured by indirect calorimeter and total daily energy expenditure was estimated by summation of energy costs of different activities. The overweight group had significantly higher values of body weight, triceps skinfold thickness, thigh circumference, waist circumference, hip circumference, BMI, WTR, WHR, body surface area, percentage body fat, fat mass, fat free mass (FFM), and muscle mass compared to normal-weight group. The energy intakes of both groups were close to RDA and other nutrient intake status was also satisfactory. There were no significant differences in intakes of energy and nutrients between the two groups. Overweight subjects showed lower energy expenditure per kg body weight for reading the newspaper, washing dishes and mopping the floor, and walking on a treadmill at 2.0 and 3.5 mph, however, energy expenditure per kg FFM did not differ between the two groups. Daily energy expenditure for all activities was significantly higher in the overweight compared to the normal-weight group due to higher body weight. Both overweight and normal-weight groups showed negative energy balance between energy intake and energy expenditure, and there was no significant difference in energy balance between the two roups. Total daily energy expenditure correlated highly with FFM and body surface area. The result of present study does not offer an explanation on the energy imbalance and weight gain of overweight women.

• 한국물환경학회지
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• 제23권5호
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• pp.607-612
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• 2007

In this study, we investigated the variations of the kinetic coefficients and Chemical Oxygen Demand (COD), N and P mass used for assimilation of a sequencing batch reactor (SBR) system with the variation of SRTs; SRTs of 7.5, 10.0, 12.5, 15.0 and 20.0 days were tested in one cycle of SBR operation to determine the optimum conditions for the operation of the SBR and estimate its COD, nitrogen and phosphorus removal efficiencies. The SBR system was operated under the conditions as follows: an operation time of 6 hours per cycle, a hydraulic retention time (HRT) of 12 hours, an influent COD loading of $0.4kg/m^3/day$, and an influent nitrogen loading of $0.068kgT-N/m^3/day$. The yield coefficient (Y) and decay rate coefficient ($k_d$) were estimated to be 0.4198 kgMLVSS/kgCOD and $0.0107day^{-1}$ by calculating the removal rate of substrate according to the variation of SRT. Considering total nitrogen amount removed by sludge waste process, eliminated by denitrification, and in clarified water effluent with reference to 150 mg/cycle of influent nitrogen amount, the percentage of nitrogen mass balance from the ratio of the nitrogen amount in effluent (N output) to that in influent (N input) for Runs 1~5 were 95.5, 97.0, 95.5, 99.5, and 95.5%, respectively, which is well accounted for, with mass balances close to 100%.

• 환경생물
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• 제31권1호
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• pp.19-36
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• 2013

남해 동부해역에서 해수는 계절에 따라 서로 다른 수질환경 특성의 수괴들에 의해 조절되는 것으로 밝혀졌다. 홍수기인 여름철 표층수는 북한한류 기원의 동해 냉수괴 특성의 수괴-A (East Sea Cold Water), 담수의 영향이 강한 연안성 수괴-B (river-dominated coastal water), 연안 염하구성 수괴-C (coastal pseudo-estuarine water)로 구분된다. 특징적으로 높은 영양염과 엽록소 농도를 갖는 저염의 염하구성 수괴-B는 홍수기인 여름철에 해안선에서 수 십 km 떨어진 해역까지 짧은 기간 일시적으로 형성되며, 집중호우 등 몬순(monsoon)기후 특성을 갖는 우리나라 연안역에서 육지-해양간 물질 순환에 상당한 역할을 할 것으로 사료된다. 여름철 저층수는 저온-고염의 냉수인 저층 냉수괴-D(bottom cold water)가 지배적이며, 표층수의 수괴들과 비교하여 전체적으로 수온, pH, 용존 산소량은 낮은 반면, 높은 영양염 농도 특성을 갖는다. 여름철 저층 냉수괴의 높은 영양염 농도는 강한 성층과 낮은 수온으로 인하여 식물플랑크톤 번식이 제한되어 보존-축적된 결과로, 갈수기인 겨울철 영양염의 주요 공급원으로 작용한다. 갈수기인 겨울철 연구해역의 해수환경은 여름철과 다르게 대마난류수 (수괴-E)가 광범위하게 분포하며, 해안선을 따라 연안역의 좁은 범위에 대마난류수가 약간 변질된 연안성 수괴-F가 분포한다. 특히 광양만, 마산만 등의 반폐쇄성 지형의 여러 만(bay)들에 위치하는 연안성 수괴-F에서는 갈수기인 겨울철에도 낮은 수심과 느린 유속 등에 의해 기초생산력이 높으며, 이로인한 겨울철 영양염 고갈(depletion) 현상이 뚜렷하게 나타난다. 또한 남해 연안성 수괴와 대마난류 수괴사이에 연안전선이 발달하며, 이러한 전선은 직간접적으로 남해의 기초생산력을 조절하는 중요 환경요소로 작용할 것으로 예상된다. 결론적으로 연구해역은 계절적으로 다른 특성의 수괴의 수괴가 복합적으로 분포하며, 여름철의 수질환경과 일차 생태계는 크게 연안 염하구성 수괴와 저층의 냉수괴 발달 정도에 따라 변화할 것으로 예상되며, 겨울철에는 외양에서 유입되는 대마난류 수괴의 특성에 따라 지배될 것으로 분석된다. 또한 용존무기인이 잠재적 제한영양염으로 작용하는 서해 연안역과 달리 남해 연안역은 대부분 용존무기질소가 잠재적 제한영양염으로 작용하는 것으로 밝혀졌다. 이러한 제한영양염의 차이는 서해와 남해 연안역이 서로 다른 환경과 다른 생태계 구조를 갖고 있음을 지시한다.

• 한국습지학회지
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• 제10권3호
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• pp.1-7
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• 2008

본 연구에서는 논에서의 영양물질 제거능력에 대하여 평가하였다. 논을 인공습지라는 관점으로 보고 전라남도 함평군 엄다면 화양리의 논 지구(이하 학야지구)를 시험지구로 선정하여 2004년 5월부터 9월까지 영농기 기간동안 조사하였다. 학야지구를 대상으로 물수지 및 물질수지를 조사하여 논에서의 T-N, T-P의 제거능력을 조사한 결과 지표유출 부하로 T-N, T-P가 각각 20.82 kg/ha, 1.55 kg/ha로 나타났으며, 이는 연구대상 논에 총 투입된 T-N, T-P의 13.2%와 6.4%에 해당되는 양이다. 연구 결과는 투입된 대부분의 영양물질이 논에서 처리됨을 보여주었다.

• 한국식품영양과학회지
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• 제26권3호
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• pp.521-527
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• 1997

This study was aimed to investigate the nutriational status of Korean female college students who are attending school at a longdistance. Physique calssification by anthropomethic indexes, Body mass index(BMI) & Brocas' index and the body fat distrubition were investigated. The energy balance was also examined comparing caloric intake with caloric expenditure. The result of this study are followings; (1) Average height and weight were 158±17.8 cm, 51.7±7.8 kg. This results were not quite different from '84 Korean Adult Standard of 159.5cm, 52.5kg. (2) By Broca's index, 25.89% of subjects was underweight 67.0% was normal weight and 7.06 was overweight. By BMI, 40% of subjects was underweight, 58.8% was normal weight and 1.2% was overweight. (3) According to % fat measured. By BIA, 7% in subjects was underweight, 64.2% was normal weight, 22% was overweight and 6.1% was obesity. This result differed from BMI's result. It may be measurement error due to the difficulty of removing metal sticking to underwear and tooth correction. (4) The intakes of the nutrients except protein, P, vitamin B₁ complexes, were lower than the intakes indicated by Korean Recommended Allowances. 95) Average caloric intake a day was 1545±394.4 kcal, which was much lower than the RDA. The caloric expenditure was much more than caloric intake, which showed negative energy balance in the subjects of this study.