• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.599-602
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• 2003

The objective of this study is to analyze the function of the paddy-field in purifying water quality. This study was carried out is based on the data in the six case studies. To improve purification function of paddy field, the following farming management is required. 1) A guideline to control the inlet and outlet of the paddy plot is need to minimize drainage water by means of a reasonable irrigation management. 2) A guideline for fertilizer application in consideration of loading nutrients dissolved in irrigation water. 3) The reuse system of agricultural drainage water is required to minimize impacts on water quality of surface water(reservoir and river).

• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.161-163
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• 2006

This paper introduce the technology of peak demand reduction using automatic water tank pumping system on the apartment. That systems on the apartments installed water tank can control pumping(electricity) demand. Generally, system peak demand is occurred at the same time on workday and many water pumps consume electric power randomly. At this point, shift of operating time of water pump can reduce peak demand using automatic water tank pumping system. We were operating this system on some apartments for test of effect of peak demand reduction. and we represent result of demand shift. This result suggests that spread of the automatic water pumping system can contribute to reduce system peak demand and reduce system operation cost.

• Journal of Environmental Science International
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• v.18 no.2
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• pp.187-195
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• 2009

This study was investigated to control the corrosion and scale at the cooling water system in steel works. Laboratory and field tests were performed for the indirect cooling water system of plate mill. Throughout the experiment, various factors such as leakage of pipes, heating rate and capacity, and the reaction between existing and substitute inhibitors were carefully monitored. The results showed that the harmful effect of high temperature could be minimized, and satisfactory corrosion/scale controls were effectively achieved using inhibitor, even at the increased temperature of $80^{\circ}C$. The batch and field tests in the gas scrubbing cooling water system of blast furnace and cooling water system of corex plant indicated that the new inhibitor was more effective for the prevention of corrosion and scale than the existing one.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.698-699
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• 2015

가로등은 공공 부문 전력 사용량 중 절대적인 비중을 차지하지만 불필요한 전력 소모로 인한 낭비요인이 적지 않았다. 통상적으로 가로등은 조금만 어두워도 안전사고 우려가 높아 법적 기준보다 10~20% 정도 밝게 설계되고 있는 실정이다. 그래서 도로조명의 가로등은 에너지절약을 위하여 격등방식으로 사용하고 있으나 등주사이의 조도분포가 균일하지 않아, 조도가 낮은 곳에서 운전자가 불안감을 느끼고 피로가 증가하여 사고로 이어지며, 조도조절이 불가능해 차량 이동이 적은 새벽 시간까지 밝게 유지해야 하는 비효율이 발생, 불필요한 전력소모로 이어지는 등의 문제점에 대해서 본 고에서는 가로등에 디밍제어 시스템을 구현하여 안정적인 조도 유지하고 에너지 절감효과를 증가시킬 수 있는 방안에 대해 고찰하고자 한다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.405-407
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• 2005

To evaluate the main hydrogeochemical characteristics, river waters are investigated using element리 and isotopic compositions in South Korea. In this area, the chemical compositions are mostly classified into three groups; $Ca^{2+}-{HCO_3}^-$ type, $Ca^{2+}-Cl^{-}-{NO_3}^-$ type and $Ca^{2+}-{HCO_3}^{-}-Cl^{-}-{NO_3}^-$ type. These types are affected by two major factors: water-rock interaction and anthropogenic inputs such as sewage and fertilizers. Based on the values of ${\delta}^{18}O$ and ${\delta}D$, most of waters are originated from precipitation except two samples contaminated. The lithology and geography of basins mainly control the water chemistry. Elemental and isotopic compositions show that water chemistry are mainly controlled by three end members, especially by carbonate dissolution, and suggest that anthropogenic input affect the water chemistry. Also, three weathering sources are identified: silicates, dolomite and limestone.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.2
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• pp.207-214
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• 2013

To evaluate characteristics of water quality in Jeju, a study was implemented for Han stream and retention ponds. Inflow water quality of retention ponds was heavily dependent on precedent rainfall, and no pesticide was detected due to the little artificial pollution sources. A smooth settling efficiency curve was noticed because heavy particles were already settled down in front of the retention pond. There were weak relationships between retention time and water quality, and this can be attributable to high concentration of pollutants influx at peak inflow. In addition, as Han stream retention pond has a role of groundwater recharge, inflow control based on water quality as well as quantity is needed to maximize pollutant removal at the retention ponds.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.790-793
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• 2004

TM/TC system is composed of control center, reservoirs, pumping stations and twelve canal systems. For this system we developed water management program which includes flood forecast program, drought reduction program, irrigation scheduling program and database program. With these program we expect that operators improve the irrigation efficiencies of the irrigation systems due to the timely irrigation on a right place, in a proper quantity and refute tile cost of maintenance and reduce flood and drought damages. In agricultural engineering respect, the databases including water level, rainfall, the amount of flowing can be useful to the researcher who make a study of hydrology and hydraulics in . rural area. Water management program records all of the TM/TC data to MDB format file per 10 minutes.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1464-1468
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• 2007

The restoration project of Cheonggyecheon was conducted to creates the refreshing water-friendly environment in the downtown Seoul. It already have passed almost 2 years after restoration. This project changed environment of Cheonggyecheon dramatically, so historic hydrological data became useless. There are not so many hydrological data to manage and control this newly restored urban stream. The main purpose of this study is collecting and analysing the hydrological data of Cheonggyecheon. At first, we analysed the mechanism of Cheonggyecheon discharge using the sewage design maps and some GIS data. We also monitored the water levels and discharges of 5 main points of Cheonggyecheon. Rating curves of these 5 points were derived. There were 249 blocks of water gates which were located at both sides of bank. We also monitored the behaviors of these water gates. Through the these monitorings, some equations were derived to give useful information to the manager of Cheonggyecheon.

• Journal of Plant Biology
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• v.18 no.4
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• pp.143-149
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• 1975

For the evaluation of drought resistance of the plant, the growth of Lespedeza bicolor Turcz. var. japonica Nakai was analyzed by the control of water content of soil: 1. The growth of leaf, stem and root showed high value in accordance with the increase of soil water content. 2. The formation of nodule was alos increased as the content of soil water became higher. 3. The highest water content of the plant was shown in the plots of 30 and 40% of water centent in soils and in the middle of the growing period (August-September). 4. The C/F ratio in the early period of the growth(July) was similar in each plot, but showed a higher value as the water centent of soil became higher at the later period(October). 5. The T/R ration increased in early period of the growth as the soil water content became higher, but it was decreased to the value of 1 in each plot.

• Journal of Wetlands Research
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• v.4 no.1
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• pp.51-61
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• 2002

The wetland is a biologically integrated system consisting of water, soil, bacteria, plants, and animals. The wetland helps sustain the ecosystem, control the micro-climate and flood, maintain the ground water level, and provide fishing grounds. From the environmental standpoint, the wetland plays a vital role in reducing water pollution by filtering out sand and other polluted matters, producing oxygen, absorbing chemicals and nutrients. For these reasons, interest in restoring the wetlands has been steadily increasing. Artificial wetland, which is also referred to as created wetland or constructed wetland, is an alternative to natural wetland. Like natural wetland, artificial wetland is environmentally friendly and can effectively lower pollutant levels. The Korea government is actively reviewing the construction of artificial wetlands in mining and water supply areas to decrease nonpoint pollutant sources. This paper attempts to develop a pollutant removal model for the water quality improvement function of artificial wetlands. Artificial wetland can improve the quality of the water; however, depending on the type of water inflow, vegetation and hydrology, its effect can be different.