• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.162-164
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• 2000

소수력 발전은 국토의 효율적 이용과 함께 녹색의 재생에너지로 정부차원에서 건설자금과 기술을 지원하고 있다. 1984년부터 한국에너지기술연구소에서 소수력입지 조사분석, 한국형 소수력발전시스템 개발연구가 활발하게 수행되었다. 소수력발전소의 중요한 과제는 경제성 있는 지점의 선정과 운영기술의 확립으로 나타났다. 본 연구에서는 저수지에서 취수하는 광역상수도에서 소수력발전소에 대한 설계와 운영방안을 제시하고자 한다.

• Journal of the Korean Professional Engineers Association
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• v.42 no.3
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• pp.22-26
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• 2009

As Korea's water resources are dominated by intense summer rainfall and steep mountainous territory, it is inevitable for most of the rainfall in Korea to flow into sea immediately and directly. It cannot help having severe conditions which droughts and floods occur repeatedly due to the seasonal and geological conditions in Korea. Those kinds of disasters will be expected more frequently and seriously in the future because of the unexpected climate changes in the world. Therefore, Korean government will plan to develop small and medium-size dams environmentally friendly, multi-regional water supply system continuously and alternative water resources such as river bank filtrations, rainwater storages and underground dams, in order to prevent floods as well as to secure stable water supply.

• Proceedings of the Membrane Society of Korea Conference
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• 1995.10a
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• pp.58-73
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• 1995

Membrane filtration is a promising technology for efficient solid/liquid separation in water purification. In FY 1991, the Ministry of Health and Welfare, Japanese Government launched a comprehensive research project "MAC 21" for development of membrane technology and its application to public water supply. The project was conducted by the Water Purification Process Association (WPPA), under the supervision of the Institute of Public Health. By the research project from FY 1991 to FY 1993, we confirmed that microfiltration (MF)/ultrafiltration (UF) technology was applicable to water purification and MF/UF was a effective method for the removal of such contaminants as particulate matter and coliforms. The Guideline Committee organized under the Technical Committee prepared a the guidelines on application of membrane system to small-scale public water supplies, based on the results as written above. The guidelines has been published in Dec., 1994 by WPPA.4 by WPPA.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.144-148
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• 2002

This study was carried out to investigate sewage treatment efficiencies using water hyacinth (Eichhornia crassipes) and watercress (Oenanthe Javanica). In the hyacinth system about 30% of COD introduced was removed during 2 days of hydraulic retention time, and about 30$\sim$50% of COD was removed in the watercress system during 1.2$\sim$2 days of hydraulic retention time. Therefore, COD loading of $76\sim170$ kg $COD/ha{\cdot}day$ was removed during 2$\sim$3 days of hydraulic retention time at the 0.18 $m^2$ area in the water hyacinth-watercress continuous system. Also 40$\sim$50% of N and P in the sewage were removed in the tested water hyacinth-watercress system Although COD, N and P concentrations in the final effluent were still higher than the limits of waste discharge, applicability of this waste water treatment system should be further investigated as an alternative method far small scale sewage treatments.

• Membrane and Water Treatment
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• v.2 no.3
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• pp.147-158
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• 2011

Membrane distillation process was used for desalination of hot (333 K) geothermal water, which was applied in the plant producing heating water. The investigated water contained 120 g salts/$dm^3$, mainly NaCl. The mineral composition was studied using an ion chromatography method. The obtained rejection of solutes was closed to 100%, but the small amounts of $NH_3$ also diffused through the membrane together with water vapour. However, the composition of obtained distillate allowed to use it as a makeup water in the heating water system. The geothermal water under study was concentrated from 120 to 286 g NaCl/$dm^3$. This increase in the solution concentration caused the permeate flux decline by a 10-20%. The geothermal water contained sulphates, which was subjected to two-fold concentration to achieve the concentration 2.4-2.6 g $SO{_4}{^{2-}}/dm^3$ and the sulphates then crystallized in the form of calcium sulphate. As a results, an intensive membranes scaling and the permeate flux decline was observed. The XRD analysis indicated that beside the gypsum also the NaCl crystallites were deposited on the membrane surfaces. The fresh geothermal water dissolved the mixed $CaSO_4$ and NaCl deposit from the membrane surface. This property can be utilized for self-cleaning of MD modules. Using a batch feeding of MD installation, the concentration of geothermal water was carried out over 800 h, without significant performance losses.

• Fire Science and Engineering
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• v.27 no.3
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• pp.38-46
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• 2013

Permanent water supply and water sprinkling systems are essential to protect major forests and facilities from forest fire. Back in 2005, Naksan Temple, a valuable cultural asset of Korea, was burned down in a forest fire that took place in Yangyang. This started a series of movements including installing water supply facilities and managing forests near important cultural assets. As for the existing facilities, however, they were installed without any standard guidelines for management and installation according to each constructor's specifications, which were based on the National Fire Safety Code 109. Unfortunately, this is not effective in protecting facilities from forest fires such as they have a small protection area, limited simultaneous sprinkling, and a difficult the movement of fire hose. Against this background, the study examines the condition of water supply facilities currently in use, identifies their deficiencies, and suggests how to improve the criteria for water supply service to effectively prevent forest fire. Specifically, three systems were proposed: Water Sprinkler Tower System for preventing spread of crown fires, and Forest Fire Hydrant System and Portable Water Spray System to be effective for suppressing surface fires. In addition, the standards on the performance and components of water pumps are also suggested.

• Journal of Korean Society on Water Environment
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• v.25 no.5
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• pp.792-802
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• 2009

The objective of this study is to construct the watershed management system with link of the non-point sources model and to estimate delivery ratio duration curves for various pollutants. For the total water pollution load management system, non-point source model should be performed with the study of the characteristic about non-point sources and loadings of non-point source and the allotment of pollutant in each area. In this study, daily flow rates and delivered pollutant loads of Nakdong river basin are simulated with modified TANK model and minimum variance unbiased estimator and SWAT model. Based on the simulation results, flow duration curves, load duration curves, and delivery ratio duration curves have been established. Then GIS analysis is performed to obtain several hydrological geomorphic characteristics such as watershed area, stream length, watershed slope and runoff curve number. As a result, the SWAT simulation results show good agreements in terms of discharge, BOD, TN, TP but for more exact simulation should be kept studying about variables and parameters which are needed for simulation. And as a result of the characteristic discharges, pollutants loading with the runoff and delivery ratios, non-point sources effects were higher than point sources effects in the small-scale test bed of Nakdong river basin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.2
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• pp.149-153
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• 1992

The antimutagenic effect of green-ye1low vegetables on the mutagenicities induced by N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) and N-nitrosodimethylamine (NDMA) in Salmonella assay system and also their inhibitory effect on AZ-521 human gastric cancer cells were studied. Twenty-four items from twenty six kinds of vegetables(92%) revealed antimutagenic activity toward MNNG (p< 0.0l, 0.05). Perilla leaf, Korean cabbage, cauliflower, lettuce, mustard leaf, water dropwort, small water dropwort, carrot and burdock inhibited the mutagenicity more than 80%. The methanol extracts of the vegetables also showed the antimutagenic activity toward NDMA (p< 0.01, 0.05). Especially, perilla leaf, kale, soybean sprout and onion inhibited more than 80% of the NDMA induced mutagenicity in S. typhimurium TA100. Small water dropwort and perilla leaf exhibited the strong inhibitory effect (97~100%) on the growth of the AZ-521 human gastric cancer cells. Soybean sprout, water dropwort, broccoli, crown daisy, green red pepper, red pepper leaves, spinach, cabbage and sweet potato also inhibited growth of the cancer cells (p < 0.001~0.05).

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.6
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• pp.15-20
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• 2008

Hydraulic analysis of water distribution system can be divided into demand-driven analysis and pressure-driven analysis. Demanddriven analysis can give unrealistic results to simulate hydraulic conditions under abnormal operating conditions such as sudden demand increase and pipe failure. In Korea, demand-driven analysis has been used to establish emergency water supply plan in many water projects, but it is necessary to use pressure-driven analysis for establishment of emergency water supply plan. In this study, WaterGEMS model that was developed for pressure-driven analysis is used to evaluation of emergency water supply plan of J city. As the results, it was able to draw up more efficient plan for water supply in small block, and established emergency water supply plan of J city was determined to be appropriate.

• Journal of Environmental Impact Assessment
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• v.17 no.1
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• pp.47-56
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• 2008

Total Maximum Daily Load(TMDL) is a core basin management system to assign total emissions of pollutants to unit basin and emission source within a limit of the target water quality and to secure sustainability. considering "Environment and development" together. By current technical guidance of TMDL, the water quality in the riverbed of which the target water quality is noticed, must achieve the target; and the water quality standard for evaluating achievement of the target should be prescribed as non-excessive probability quality of water on the basis of the pertinent water quality documents. Therefore, the study calculated the target water quality by each unit basin which the target water quality must be noticed through the analysis of probability for water quality documents in rivers at the time of establishing a plan, and the study evaluated the achievement possibility of the target water quality by analyzing and comparing the target water quality plan with the standard water quality to evaluate the achievement of the target water quality. As the result, applying the proposed method to Mihocheon River system, it is concluded that selected the target water quality (Each BOD 3.3mg/1 and BOD 3.0mg/1) in Miho A and Musim A is available. Of course, it showed that the target water quality: BOD 2.5mg/1 in Miho A and BOD 3.0mg/1 in Musim A, could be achieved if the small reduction in B unit area was implemented.