• 한국물환경학회지
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• 제25권4호
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• pp.615-623
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• 2009

The research of the determination of event mean concentration (EMC) was focussed combined sewer overflows and highway runoff in korea. But those of non-urban areas are few. In this study, EMC and unit loading on land use types in Nogok watershed were estimated by runoff loading of non-point source (NPS) on non-urban area. Two monitoring sites were equipped with an automatic velocity meter, flow meter, and water sampler. Monitoring was conducted at two monitering site during the rainy season. The results show that the EMC ranges in forest land use are 1.3~2.6 mg/L for BOD, 2.0~16.1 mg/L for SS, 0.1~2.1 mg/L for TN, and 0.12~0.49 mg/L for TP. The unit loading of NPS in this study was difficult to compare directly with that used conventionally because of the difference of field investigation. In near future, it needs to conduct more systematic and long-term research about NPS within the watershed. The results of this research can be used to estimate the total pollution load management system (TPLMS) program in korea.

• 한국태양에너지학회 논문집
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• 제36권6호
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• pp.61-69
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• 2016

In this study, we analyzed five-year(2011~2015) data for D high school in Seoul area to analyze energy consumption characteristics in high school. The results are summarized as follows. (1) In the result of comparison analysis about 2015 energy consumption by usage, based on primary energy, 18% of energy was consumed in cafeteria, and 82% was consumed in main building. In the case of main building, base and constant load excepting hot water supply in restroom took 40%, heating including freeze protection took 20%, hot water supply in restroom took 14%, and cooling took 8% in order. (2) In the 2015 total energy consumption in D high school based on primary energy, heating energy takes 28%. The range and limit of energy savings coming from the reinforcement of insulation and window performance could be estimated. (3) To introduce new & renewable energy system in high school, electricity-based system is suitable than heat-based system because usage of electric energy is larger than that of heat energy in high school. (4) Five-year energy consumption unit according to heating degree-day showed a linearly increasing trend, and the coefficient of determination(R2) was 0.9763, which means high correlation.

• 한국작물학회지
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• 제36권4호
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• pp.319-323
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• 1991

벼의 도복에 관련하는 형질들의 포장도복과의 관련정도를 밝혀 벼의 이도복성육종의 기초자료를 제공코져 1900년대에서 1980년대에 재배 또는 육성된 10품종을 재배하여 실험한 결과를 요약하면 다음과 같다. 1 포장도복정도와 관련정도가 높은 형질들은 간장, 단위간하중(W/l), 단위 직경휨모멘트(W1/d), 도복지수(L), 하중비(W1/P), 임계도 복하중지수 (Ws$^2$/l$^4$)등 이었다. 2. 간장은 포장도복과 높은 상관(r=0.7607)을 보이나 간장만으로 품종의 도복정도를 판정하기는 미흡하였다 3. 측정의 난역도와 소모되는 시간을 고찰해 볼 때 도복저항성을 판정하는데 유용할 형질들은 간장, W/l, W1/d, Ws$^2$/l$^4$이었다. 4. 간경, 줄기단면적, 간벽의 두께, 줄기단면의 2차 관성 모멘트는 포장도복과 아무런 상관관계를 보이지 않았다. 5. 좌절강도(S)는 포장도복과 유의한 부의 상관 (r=-0.3986)을 보였다.

• 한국환경과학회지
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• 제11권9호
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• pp.945-954
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• 2002

The objective okgf this study is understanding and evaluation of temporal and spatial variation of pollutant loads by input sources for water quality management in Kamak Bay. Flow rate of rivers and ditches ranges from about $2,592-63,072m^3/d$ in October to $864-55,296m^3/d$ in January. In particular, the R2 predominated flow rate among input sources. Total COD, BOD, DIN and DIP loadings in January were about 896kg/d, 718kg/d, 2,152kg/d, and 154kg/d, respectively, which exceeded those of October. Lower POC/TOC levels are estimated in R2, and also in October. Temporal variation of pollutant loads were closely related to the human activity. Total discharging loadings of BOD, TN and TP by unit loading estimation were 4,993.0kg/d, 2,558.7kg/d, and 289.2kg/d, respectively, and were mainly affected by the population. Runoff ratio of BOD was about 0.14 in January Mean $NH_4^＋_-N$ and $PO_4\;^{3-}-P$ loadings from sediment were 16.23mg/$m^2$/d and 7.26mg/$m^2$/d, respectively. For the improvement of water quality in this area, not only pollutant loads of rivers and ditches but also benthic flux from sediment should be reduced within the limits of the environmental capacity.

• 대한전기학회논문지:전력기술부문A
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• 제48권10호
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• pp.1190-1197
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• 1999

The management of power factor(PF) in the distribution line is treated according to the measurement a month about the feeder unit at the substation. In Korea, we have not researched into power factor in distribution system due to it's less weight. The reactive power in advanced countries is controlled automatically by the compensative condenser switch on/off under the monitoring. This paper first presents the optimal condenser position and proper capacity by lagrangue factor ${\lambda}_{Q}$ which is the line loss index about reactive power unit. Therefore, the largest ${\lambda}_{Q}$ node is the condenser injection point and we find out the best condenser capacity when the line loss is saturated by the moderation of condenser volume. By this method, we suggest 0.6% uprising PF by injection of 15 kVA condenser. Additionally, PF is analysed into 5 areas; large city, middle city, small city, farm village, fishing village by the use of Power Platform which is classified the same concept of the low load management in KEPCO. Two feeders of each area are selected by the worst results of PF in specified areas.

• 대한교통학회지
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• 제22권2호
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• pp.109-119
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• 2004

COSMOS는 1990년부터 개발되어 현재까지 현장실험 및 시스템 검증과 여러 차례의 기능개선을 통하여 점차 안정화 되어가고 있으며, 그 효율성이 입증되어 서울시 전역으로 확산되고 있는 추세이다. 그러나 현재는 CI의 옵셋패턴이 한쪽 축 방향의 유입/유출 이동류에 의해서만 산출되고 있어, 다른 축방향에 속한 교차로는 자신과 무관한 옵셋패턴에 의해 운영되는 경우가 발생한다. 또한 Sub Area 결합/분리시 CI의 유입/유출 방향의 축에 속한 Sub Area와의 결합/분리만이 가능한 실정이다. 따라서 본 연구에서는 CI의 동서와 남북 축 각각의 유입/유출 방향을 설정하여, 두 축의 옵셋패턴과 현재 운영 주축을 계산하여 설정하도록 하였다. Sub Area 내의교차로들은 자신이 속한 축의 옵셋패턴에 의해 운영되며, 결합/분리시에는 주축방향간의 '결합'과 이외의 경우의 '연동'의 개념으로 운영되도록 하였다. 개선된 알고리즘은 COSMOS 운영 S/W에 탑재하여, 강남구 10여개 교차로를 대상으로 기능성 평가 및 효율성 평가를 실시하였다. 평가 결과 개선 알고리즘이 기존방식보다 통행시간을 감소시키는 것으로 나타났다.

• 한국안전학회지
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• 제25권3호
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• pp.15-21
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• 2010

A differential case equipped with LSD(limited slip differential) has several advantages over a normal type for rear wheel drive vehicles. Specially, the torque distribution can be done between left and right drive wheel in the state of limited slip differential. Also although LSD types are very various according to operating type, medium and torque distribution, a multi-clutch type is generally applied to rear wheel drive vehicles. So, this study presents the analysis of design parameters for development of a friction plate for multi-clutch type LSD using vehicle road test, the simulation of analytical model and the development of vehicle dynamics model by a benchmark product. According to this investigation, the design parameters which are pre-load of coil spring, friction plate and contact area quantity, friction coefficient and TBR(torque bias ratio) for a friction plate are derived from experiment and simulation and consequently, vehicle dynamics model has been constructed for the development of friction plate for multi-clutch type LSD.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.451-456
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• 2012

This study was carried out to evaluate thermal performance of the renewable hybrid heat supply system with solar thermal system and wood pellet boiler for Zero Carbon Green home of apartment houses. The hybrid heat supply system was set up at Korea Institute Energy Research in 2011. The system was comprised of the wood pellet boiler unit with heat capacity designed as 20,000 kacal/hr, a evacuated tubular solar collector 3.74 $m^2$ of aperture area at the $20^{\circ}$ install angle, a 0.3 $m^3$ hot water storage tank, a 0.15 $m^3$ hot water storage tank for space heating. Thermal performance tests for one-house of apartment house were carried out by hot water load and heating load in winter season through the hybrid heat supply system. As a result, hot water energy supplied by the hybrid heat supply system was 11kWh in a day. Solar thermal energy portion was 2.99kWh which is 27% of the total hot water energy supply. wood pellet boiler supply portion was 8.017kWh which is 73% of the total hot water energy supply.

• 한국농공학회논문집
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• 제53권4호
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• pp.11-19
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• 2011

PADDIMOD2 was deloped to estimate nonpoint source pollution from paddy rice fields. The PADDIMOD2 was enhanced to estimate runoff and pollutant load during non-growing as well as growing season and to be easily used for public by development of Excel based system. Nutrient concentration and hydrology were based on Dirac delta function and continuous source function, and tank model for growing season and Event Mean Concentrations (EMCs) and SCS-Curve Number method for non-growing season. The PADDIMOD2 consists of three main component (input data, parameters data, and output data) by including eight Excel spread sheets. As a result of model application, total precipitation and irrigation were 1,051.7 mm and 439.2 mm, respectivley and surface runoff and water loss including infiltration and evapotranspiration were 463.0 mm and 947.9 mm, respectively. Annual nutrient loadings of T-N and T-P from study area were 6.7 kg/$km^2$/day and 0.5 kg/$km^2$/day, respectively. Development of PADDIMOD2 was focused on minimizing input data and maximizing user friendly system and is expected to be useful tool to evaluate various non-structure BMPs and estimate unit load from paddy rice fields for application at Korean TMDL.

• 한국습지학회지
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• 제9권3호
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• pp.43-49
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• 2007

최근 환경부의 환경정책은 수질오염총량관리제도의 전국적인 확대를 앞두고 다양한 토지이용에서 발생되는 비점오염물질의 관리를 추진하고 있다. 특히 도로, 고속도로 및 주차장 등의 포장된 지역은 수계 인근에 존재하고 있기에 비점오염원 관리에서 우선순위로 인정되고 있다. 본 연구의 토지이용인 주차장은 많은 차량의 운행, 정차 및 주차로 인하여 다량의 입자상 물질이 포함된 비점오염물질의 축적이 높은 토지이용이다. 또한 높은 포장율로 인하여 강우 발생시 다량의 강우유출수가 비점오염물질을 함유하여 배수구로 유출되는 특성을 가지고 있다. 이러한 맨홀은 강우시 유출된 강우 유출수를 짧은 기간이지만 체류시켜 입자상 물질을 처리하는 기능을 가지고 있다. 따라서 본 연구는 주차장 맨홀에서의 퇴적물을 채취하여 입자상 물질 입도별 중금속의 함량을 조사함으로써 맨홀에 의한 비점오염물질의 제거율을 분석하고자 한다. 또한 중금속으로 오염된 퇴적물의 효과적 관리방안을 제시하기 위하여 본 연구는 수행되었다. 이러한 연구를 위하여 채취된 퇴적물의 입도분석이 시행되었으며, 입도분포별 중금속의 오염도를 조사하였다. 입도분석을 수행한 결과 $425-850{\mu}m$ 사이의 입도가 가장 많은 범위를 차지하고 있는 것으로 나타났다. 입도 크기와 중금속의 함량을 분석한 결과 입도크기가 적을수록 높은 중금속의 함량을 나타내었다. 중금속 중에서 Cu, Pb, Zn의 함량이 전체 중금속의 30% 정도를 차지하는 것으로 나타났는데 그 이유는 이러한 오염물질이 차량의 타이어와 엔진파트에 많이 함유된 중금속이기 때문이다. 본 연구를 통해 주차장의 맨홀은 비점오염물질의 제거에 많은 기여를 한다는 것을 확인할 수 있었으며, 향후 주차장의 비점오염원 관리에 있어서 맨홀의 개량을 통해 더욱 더 높은 비점오염물질의 제거를 수행할 수 있다는 것을 확인할 수 있었다.