• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.500-507
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• 1998

The measures for water quality improvement have been planned to introduce for several reservoirs which were badly polluted among the sites included in the Network of Agricultural Water Quality Survey (NAWQS). Considering conditions of circumstances around reservoirs, self-purification systems such as natural ecosystem, oxidation ponds with plants, grassed waterways, weirs, and manmade plant-islands are taking into account enhancing to trap nutrients in waters running off from agricultural lands. The Pollutant Run off Ratios were analysed to predict the effects of water quality improvement for self-purification systems. The cost of water quality improvement was evaluated. The correlation equation between cost and irrigation area showing high correlation coefficient was derived.

• 한국농공학회지
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• 제39권2호
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• pp.1-8
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• 1997

Abstract The need for integrated reservoir system operation become more intense as the demands from the system increase. A deterministic, three-dimensional discrete incremental dynamic programming approach is presented to derive reservoirs system operational planning strategies. The developed H3DP model optimizes the monthly operation of the Hwachon and Soyang Projects on the North Han river and Chungju Main Project on the South Han river. By using the H3DP model, Hwachon project was reevaluated as a component of the upstream multipurpose storage reservoirs in the basin based on 1993 hydrology. This case study demonstrates the practical use of the developed model for the basin multi-reservoir system operation in an integrated, multipurpose fashion.

• Environmental Engineering Research
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• 제20권3호
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• pp.290-297
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• 2015

This paper presents the evaluation of the impact of climate change on water resources and yield capacity of Asa and Kampe reservoirs. Trend analysis of mean temperature, runoff, rainfall and evapotranspiration was carried out using Mann Kendall and Sen's slope, while runoff was modeled as a function of temperature, rainfall and evapotranspiration using Artificial Neural Networks (ANN). Rainfall and runoff exhibited positive trends at the two dam sites and their upstream while forecasted ten-year runoff displayed increasing positive trend which indicates high reservoir inflow. The reservoir yield capacity estimated with the ANN forecasted runoff was higher by about 38% and 17% compared to that obtained with historical runoff at Asa and Kampe respectively. This is an indication that there is tendency for water resources of the reservoir to increase and thus more water will be available for water supply and irrigation to ensure food security.

• 한국농공학회논문집
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• 제48권3호
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• pp.11-20
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• 2006

In this study, the actual water management were investigated and analyzed on site for effective use of the paddy irrigation water. And this study is tried to analyze the difference between simulated irrigation water according to current design method and actual water supply in experimental reservoirs. The reservoirs in Idong, Yongdeok and Misan, which are managed by Korea Rural Community & Agriculture Corporation, were selected fur field investigation. The purpose of this study is to suggest an improved method for irrigation water calculation through quantitative and periodical analysis considering the difference between design and actual field condition.

• 한국농공학회지
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• 제40권2호
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• pp.159-170
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• 1998

This study was initiated to investigate the applicability of the dredged soil from agricultural reservoirs on the crop cultivation. Four reservoirs were selected for this experiment, and properties of the dredged soils were analyzed physically and chemically. Soil textures were sandy loam(SL), silty loam(SiL), gravelly loam(GL), graveHy silty loam(GSiL), respectively. General chemical components, organic matter contents, main cations, heavy metals, etc. showed no adverse effects on crop growth. Tomato, cucumber, radish, Chinese cabbage were cultivated during 8 months period, in the soil treated with fertilizer and compost(Tmt.1), fertilizer(Tmt.2), compost(Tmt.3) and none (Tmt.4). Data for plant height, root zone depth and crop yield were collected and analyzed, and the yield for most crops showed increase as Tmt.1 >Tmt.2>Tmt.3>Tmt.4 by fertilizing methods, and as GL>GSiL>SL>SiL by soil textures. From the results, the crop cultivation using dredged soil was considered to be effective, due to its soil texture, organic matter content and fertilization.

• 한국농공학회지
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• 제30권2호
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• pp.95-104
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• 1988

This study refers to the development of a hydrologic model simulating daily inflow and release rates for inigation reservoirs. A daily - based model is needed for adequate operation of an irrigation reservoir sufficing the water demand for paddy fields which is closely related to meteorological conditions. And the objective of this study is to develop a reservoir release rate model and then to calibrata the parameters. The release rates model considers daily water demands , water supply for transplanting, minmum release for maintaining canal flow, and maxirnun and regular flooding depth for determining effective rainfall on paddy fields. Each of the factors in the model was regarded as a lumped pararuter representing the average condition of a whole irrigated area. The water demand was estimated form the potential evapotranspiration by Penman method, the effective rainfall, and the infiltration on paddy fields. The release model was found to be capable of adequately simulating daily reservoir releases based on meteorological data.

• Journal of Ecology and Environment
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• 제37권2호
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• pp.99-104
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• 2014

We estimated the influence of environmental factors on zooplankton communities at 25 reservoirs during winter (December 2010 to January 2011). Among zooplankton groups, Cyclops vicinus is more dominant during winter, and this is positively related to withered vegetation area and dissolved oxygen level. Therefore, the presence of withered vegetation might be considered as an important factor to determine C. vicinus distribution during winter. We considered that withered vegetation might be utilized as a habitat for C. vicinus, as well as provide an attachment substrate for periphytic algae. Abundance of periphytic algae can lead to high concentration of dissolved oxygen. Although copepods prefer high water temperatures for increasing their population growth, if Cyclops can overcome low temperature stress that leads to disruption of population, their population growth initiation in the next growing season (i.e. next spring) is possibly propelled by the winter population.

• ALGAE
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• 제22권2호
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• pp.69-85
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• 2007

From six reservoirs in Gyeonggi-do, we have collected the distribution and standing crop of phytoplankton since Nov. 2005 through Sep. 2006. As a result, the phytoplankton appeared totally 340 taxa belong to 7 classes, 15 orders, 5 suborders, 32 families, 4 subfamilies, 84 genera, 283 species, 43 varieties, 9 forms and 5 unidentified species. The standing crop was shown as minimum was 0.3 × 106 cells and maximum was 5,950 × 106. The relation of standing crop with TN, TP and Chl-a showed as positive. Total 12 taxa including 2 taxa of blue-green algae occurred to every seasons at six lakes, and it was thought that they distributed in mesotrophic state. Also, Achnanthes minutissima, Aulacoseira granulata, Eudorina elegans, Gloeocystis ampla, Pandorina morum, Pediastrum simplex var. duodenarium, Scenedesmus ecornis were regarded as the indicators of eutrophic state. From the estimation of LTSI and TSI, it was shown that the rest of lakes except for Idong reservoir of winter were eutrophic states.

• 대한화학회지
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• 제16권4호
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• pp.219-228
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• 1972

Geochemical investigation of river waters and reservoirs in Seoul city on fluorine contents were conducted between June in 1969 and February in 1970. Fluorine contents of most river waters and reservoirs in Seoul city were between 0.09 and 0.32 mg/l. It was found that fluorine contents of Han River and rivers running through the outskirt of the city were relatively less than those of the river waters running through the residential areas and the industrial areas. Fluorine contents were less seasonally variable than chlorine ones. Some implications of those results were discussed in detail.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.326-329
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• 2003

When an electrokinetic process is applied to a HOC-contaminated soil, hybrid types combined with soil flushing, chemical oxidation, and bioremediation are generally used. Especially when the electrokinetic process is combined with bioremediation, the hybrid technology can solve several limits of bioremediation such as low microbial mobility, low soil temperature, and shortage of nutrients in subsurface circumstance. Because microbial surface is charged negatively, the microorganism moves from cathode to anode under electrical field. In this study, mixed culture mainly-consisted by Pseudomonas sp. was applied to remediate pentadecane-contaminated kaolinite with particle size less than 300${\mu}{\textrm}{m}$. This remediation system was named ‘electrokinetic bioaugmentation’ and consisted of model aquifer, electrode reservoirs, bioreactor, power supply, and pump. The mixed culture above 0.5 of optical density in bioreactor was supplied to two reservoirs and penetrated soil when the electric current was applied. To enhance the removal efficiency, the optimal medium composition, electric current, and voltage were investigated.