• 한국물환경학회지
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• 제29권2호
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• pp.212-222
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• 2013

A watershed model was constructed using Hydrological Simulation Program Fortran to quantitatively predict the stream flows at major tributaries of Nakdong River basin, Korea. The entire basin was divided into 32 segments to effectively account for spatial variations in meteorological data and land segment parameter values of each tributary. The model was calibrated at ten tributaries including main stream of the river for a three-year period (2008 to 2010). The deviation values (Dv) of runoff volumes for operational stream flow forecasting for a six month period (2012.1.2 to 2012.6.29) at the ten tributaries ranged from -38.1 to 23.6%, which is on average 7.8% higher than those of runoff volumes for model calibration (-12.5 to 8.2%). The increased prediction errors were mainly from the uncertainties of numerical weather prediction modeling; nevertheless the stream flow forecasting results presented in this study were in a good agreement with the measured data.

• 생물환경조절학회지
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• 제25권4호
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• pp.270-276
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• 2016

This study analysed overall heat transfer coefficient, heat transmission, and rate of indoor air heating provided by water curtain in order to determine the heat transfer characteristic of double-layered greenhouse equipped with a water curtain system. The air temperatures between the inner and outer layers were determined by the water flow rate and inlet water temperature. Higher water flow rate and inlet water temperature resulted in the increased overall heat transfer coefficient between indoor greenhouse air and water curtain. However, it was found that with higher levels of water flow rate and inlet water temperature, indoor overall heat transfer coefficient was converged about $10W{\cdot}m^{-2}{\cdot}^oC^{-1}$. The low correlation of overall heat transfer coefficient between water curtain and air within double layers was likely because the combination of greenhouse shape, wind speed and outdoor air temperature as well as water curtain affected the heat transfer characteristics. As water flow rate and inlet water temperature increased, the heat transferred into the greenhouse by water curtain also tend to rise. However it was demonstrated that the rate of heat transmission from water curtain into greenhouse with water curtain system using underground water was accounted for 22% to 28% for total heat lost by water curtain. The results of this study which quantify heat transfer coefficient and net heat transfer from water curtain may be a good reference for economical design of water curtain system.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.773-777
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• 2005

This article is about using information technology to apply with water loss inspection system in District Metering Area (DMA). Inspector can check Flow rate and Minimum Night Flow; NMF via Smart Phone or PDA include sending SMS Alert in case the Pressure, Flow rate and NMF is over the range of controlling. This will be used as equipment to implement water loss in international proactive and can keep on water loss reduction more efficiency. The system consists of Data Logger which collects data of Flow rate from DMA Master Meter. PC is Wap Server which dial via modem in order to get data through FTP Protocal that will convert text file to Microsoft Access Database. Wappage will use xhtml language to show database on Wapbrowser and can show the result on Smart Phone or PDA by graph and table for system analysis.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.26-32
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• 2008

Middle Route Project, the largest water conveyance system in China delivers the water of Changjiang River to North China. In order to create canal operation simulation system, mathematical models are established based on the analysis of hydraulics about steady flow, unsteady flow, and check gate. By simulating the canal operation behavior, we improved the check gate control algorithm and predicted the change process of water surface and flow profile which is very valuable to actual canal operation.

• 생물환경조절학회지
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• 제2권1호
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• pp.1-8
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• 1993

Experimental and theoretical analyses were carried out to investigate the heat exchange characteristics of the nutrient solution cooling system utilizing ground water. The material of heat exchanger used in the experiment was polyethylene and the cross-flow type was adapted in which nutrient solution was mixed and ground water unmixed. For the exchanger surface area of 0.33$m^2$ and flow rates of ground water of 1-6$\ell$/min, NTU(number of transfer units) and effectiveness of experimental heat exchanger were 0.1-0.45 and 10-35％, respectively. Therefore these results showed that the hydroponic greenhouse of 1,000$m^2$(300 pyong) with the ground water of 10$m^2$/day could cover about 55-70％ of maximum cooling load in summer.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.251-251
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• 2000

Tangjin Power Plant is modern Korean standard plant which is made up Once Through Super Critical Boiler, Turbin, Generator and Flue Gas Desulfarization System. INFI-90 system fur control of the 500 MW Korean standard super critical once through boiler Mark-V for Turbine, EX-2000 fer Generator, WDPF for FGD were installed in Tangiin thermal power plant. There were two BFPTs, BFPM, 25% control valve, 35% control valve to control boiler feed water flow. It is very difficult to tune the Separator Tank level control system and change the mode from Wet to Dry. This paper focuses on test results and modification control logic for feed water control system in Tangjin power plant.

• 물과 미래
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• 제35권5호
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• pp.51-59
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• 2002

In recent years the human impact on the environment becomes increasing lift threatening, calls for the better management of resources. In field of water quality of river flow, the best way to conserve water quality is specific efforts to control the pollutant loadings and treat the loadings in the basin to reduce the discharge of pollutant loadings to river. But in general the water quality influenced by the dam discharge. Especially in dry season, it is more dominant way to improve the water quality which contaminated with the pollutant loadings from the basin. The dam discharge amounts of the 2 dams in the Keum River that maintain the down stream water quality were estimated for the year of 1999, 2001, 2006, 2011, in case of irrigation and non-irrigation seasons. The pollutant loadings for the basin are estimated with the planning of treatment plants construction schedule for every sub-basins. The river flow rates were considered low flow as 2.33 year low flow and 10 year low flow. The QUAL2E model was used as a tool of simulation.

• The Korean Journal of Physiology
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• 제3권1호
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• pp.59-66
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• 1969

Experiments on thermoregulatory responses to cold immersion stimulus were carried out in September, 1968 (summer studies) and February, 1969 (winter studies). Eight each of ama and control subject were selected at random from a same community in Yong-Do Island, Pusan. The results obtained are summarized as follows: 1) The rate of fall in muscle temperature of forearm during a 30 min-immersion in $6^{\circ}C$ water bath was significantly slower in the ama in winter and was about the same in the two groups in summer. However, the magnitude of change in the skin temperature and the heat fluxes observed during immersion period was not significantly different either between groups or between seasons. 2) Both finger blood flow and skin temperature during one hr-immersion in $6^{\circ}C$ water bath decreased significantly in the ama as compared to the control. The magnitude of cold-induced vasodilatation during immersion period was significantly greater in the control in winter. However, the time of onset and blood flow at onset showed no significant relation between groups. 3) The magnitude of reactive hyperemia after a 5 min-arterial occlusion in both air and $15^{\circ}C$ water bath was significantly lower in the ana than in the control. In control subjects, post-occluded blood flow in water was significantly greater than in air, while in the ama it decreased to 1/2 of control values. The time required for the return of blood flow to resting values in the air was faster in the ama than in the control but was the same in water in the two groups. 4) The results suggest that vasoconstrictor tone increased in the ama in winter, indicating the development of vascular adaptation as a part of cold acclimatization.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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• pp.174-177
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• 2003

The automatic temperature control valve is used to control the flow rate of heating water in the large apartment complex and buildings. It is important to have simillar heating flow rate in the apartments, even though the apartment is top or bottom floors. To achieve those purposes, the automatic flow-temperature control valve was developed. The perfromance of this control valve is effected by the catridge shape and spring length. The flow capacity of this control valve is obtained with the different shape of catridges and with change of spring length.

• 한국산학기술학회논문지
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• 제11권3호
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• pp.1006-1015
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• 2010

본 논문은 호수 바닥이 오염된 서산 부남호의 수문을 개방했을 때 예상되는 오염물질의 확산에 관한 것으로 토사 부유물의 확산과 오염물질의 확산으로 나누어 모사하였다. 부남호의 수문을 열었던 예를 기준으로 극한 상황의 몇 가지 각본을 가지고 컴퓨터 모사를 한 결과 방수량 100톤/s를 기준으로 부유물은 50ppm의 농도로 3시간 방류하면 19시간 후 원상태로 회복되며, 극단적인 COD 8인 상태로 1시간 방류하다 중단하면 천수만에 위치한 가두리 양식장에 지장이 없음을 알았다.