• 생태와환경
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• 제41권3호
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• pp.360-366
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• 2008

본 연구는 심수층의 고정 취수구를 통해 방류하는 안동댐을 대상으로 1일 최대 99.4 mm, 총 299.1 mm인 단일사상의 강우로 유입된 고탁수의 호소 내 시 공간적인 거동과 방류수의 탁도가 감소하는 경향을 조사하였다. 유입된 고탁수는 중류지점부터 호소 바닥에서 이탈되어 중층 밀도류로 최하류까지 이동하였다. 강우 이전의 호소 내 탁도는 10 NTU 이하의 균일한 분포를 보였으나 강우에 의해 수심 16 m에 최고 290 NTU의 고탁수대가 형성되었다. 고탁수는 강우 후 3일부터 방류수의 탁도를 상승시켰으며 5일째에 129 NTU로 최고 탁도를 보였다. 댐까지 이동한 탁수층은 취수구 상부 5 m 이내의 수심에 최고 농도로 분포하였으며 하류 방류에 의해 탁수층의 두께와 농도가 감소하였다. 방류수의 탁도가 30 NTU까지 감소하는데 38일, 강우 이전의 상태로 회복되는데 87일이 소요되었으며, 감소경향의 상관계수는 각각 0.96, 0.97이었다. 중층에서 밀도류를 형성한 고탁수는 취수구 직상부에 분포하면서 취수구 방향으로 점차 유인되어 하류로 배출되었으며 호소 바닥으로의 침강은 일어나지 않았다. 안동호로 유입된 고탁수는 심층에 위치한 취수구를 통해 효과적으로 배출되므로 취수구 위치는 고탁수 배제에 적정한 것으로 판단된다.

• 한국농공학회논문집
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• 제57권3호
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• pp.101-108
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• 2015

The purpose of this study was to evaluate the safety of the small reservoir, which is distributed in a rural area, based on systemic reliability. It has been estimated that safety of respective reservoir the calculation of failure probability for individual reservoirs can evaluate the safety of the reservoir of the study area. The change of safety for watershed could be figured out as that result. Probability of failure was increased from $3.90{\times}10^{-5}$ to $1.35{\times}10^{-4}$ in Naesu-inpyung reservoir, from $1.33{\times}10^{-5}$ to $4.77{\times}10^{-5}$ in Buyeon reservoir and from $4.24{\times}10^{-5}$ to $2.55{\times}10^{-2}$ in Dalakmal respectively. From the results, the collapse of the upper stream reservoir was analyzed qualitatively that may affect the safety of the reservoir on the downstream area.

• 한국물환경학회지
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• 제30권1호
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• pp.31-43
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• 2014

Recently, Andong Reservoir and Imha Reservoir located in Nakdong River basin (Korea) are being connected by a tunnel (length 2km, diameter 5.5m) for a conjunctive use. The objectives of this study were to construct a two dimensional(2D) laterally-averaged model for two reservoirs, and examine the effects of connection on the water transportation and temperature stratification in the reservoirs. The 2D models for each reservoir were calibrated using field data obtained in 2006, and applied to the linked system for the year of 2002 when a severe flood intruded into Imha Reservoir during the typhoon Rusa. Simulation results showed that 364 million $m^3$ of water can be conveyed from Imha to Andong, while 291 million $m^3$ of water from Andong to Imha after connection. It resulted in 1.38 m increase of annual averaged water level in Andong Reservoir, whereas 3.75 m decrease in Imha Reservoir. The structures of thermal stratification in both reservoirs were influenced in line with the flow exchanges. In Andong Reservoir, the location of thermocline moved upward about 10 m compared to an independent operation. The results imply that the persistent turbidity issue of Imha Reservoir might be shifted to Andong Reservoir during a severe flood event after connection.

• 한국농공학회논문집
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• 제58권2호
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• pp.53-63
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• 2016

Monitoring of cyanobacteria bloom in reservoir systems is important for water managers responsible of water supply system. Cyanobacteria affect the taste and smell of water and pose considerable filtration problems at water use places. Harmful cyanobacteria bloom in reservoir have significant economic impacts. We develop a new method for estimating the cyanobacteria bloom using Landsat TM and ETM+ data. Developed model was calibrated and cross-validated with existing in situ measurements from Daecheong Reservoir's Water Quality Monitoring Program and Algae Alarm System. Measurements data of three stations taken from 2004 to 2012 were matched with radiometrically converted reflectance data from the Landsat TM and ETM+ sensor. Stepwise multiple linear regression was used to select wavelengths in the Landsat TM and ETM+ bands 1, 2 and 4 that were most significant for predicting cyanobacteria cell number and bio-volume. Based on statistical analysis, the linear models were that included visible band ratios slightly outperformed single band models. The final monitoring models captured the extents of cyanobacteria blooms throughout the 2004-2012 study period. The results serve as an added broad area monitoring tool for water resource managers and present new insight into the initiation and propagation of cyanobacteria blooms in Daecheong reservoir.

• 한국환경과학회지
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• 제14권11호
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• pp.995-1004
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• 2005

As a research establish reservoir safety operation for small dam systems. This study presents hydrologic analysis conducted in the Duckdong and Bomun dam watershed based on various rainfall data and increase inflow. Especially the Duckdong dam without flood control feature are widely exposed to the risk of flooding, thus it is constructed emergency gate at present. In this study reservoir routing program was simulation for basin runoff estimating using HEC-HMS model, the model simulation the reservoir condition of emergency Sate with and without. At the reservoir analysis results is the Duckdong dam average storage decrease $20\%$ with emergency gate than without emergency gate. Also, the Bomun dam is not affected by the Duckdong flood control augmentation.

• 한국관개배수논문집
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• 제19권1호
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• pp.77-86
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• 2012

The aim of this study was to analyze the operation plan for heightened agricultural reservoir, in terms of water supply to downstream paddy fields and instreams. Operation of agricultural reservoir before the heightened reservoir project is easy to manage because of its single purpose, which is irrigation water supply. However, after proceeding the heightened project, there is needed to be set the operation rule because of its multiple purpose, which is water for irrigation and supply to the stream. In this paper, propose the method of design the criteria of supply to the stream and operation rule curve for the heightened reservoir. According to simulation results by proposed operating rule for the Gumsa reservoir, the yearly amount of water supply to the stream can be 2,588 thousand $m^3$, 3 times of the heightened space (2,588 thousand $m^3$).

• 한국농공학회논문집
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• 제50권6호
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• pp.75-81
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• 2008

The purpose of this study was to develop an optimum equipment model considering various objective functions and variables of agricultural reservoir. Traditional optimum function for feasibility assessment is based on economic benefit, but we tried new approach of feasibility assessment based on the number of beneficiary. The data of Yuraimi reservoir and Yongbong reservoir in Yesan-gun such as numbers of related people, construction costs, safe diagnosis have been gathered for applying developed model. Data are used for determining optimum strategy with restricted cost. For verifying results of optimum maintenance, real maintenance data of Yuraimi reservoir were compared with simulated strategy. Results show that simulated maintenance strategies are 3 times more effective than real maintenance data.

• 한국물환경학회지
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• 제29권6호
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• pp.799-807
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• 2013

Reservoir sedimentation is one of the major concerns for sustainable reservoir operation. Since sediment concentration of the rivers in the Himalayan Mountain is very high, a proper sediment management scheme is necessary. This paper presents long-term reservoir sedimentation and sediment flushing based on the gate operation. Focused on the reservoir to be constructed for the Patrind hydropower project in Pakistan, 4 different flushing scenarios were proposed in this study to prevent successive sedimentation. By extending flushing period and by increasing the flushing discharge for 2 times, the flushing rate increases up to 53.2% and 43.6% in proportion to flushing period and discharge, respectively. Based on the simulation presented in this paper, it is expected to establish efficient sediment management plan to increase hydro power generation and sediment flushing simultaneously.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.1612-1615
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• 2009

Water supply reliability indexes (WSRI) is estimated for assessment of water supply capacity in the downstream for parallel reservoir system in Nakdong River, South Korea, using allocation rule (AR) according to the water supply capacity of each reservoir and the characteristic of parallel reservoir system. The result of the analyzing parallel reservoir system for Andong and Imha reservoir in Nakdong River does not include evidences available enough to decide whether the results of water supply analysis are excellent in the current reliability evaluation or not. However, AR (C) shows a good result in the water supply capacity for each reservoir based on the connected operation system and the total water supply capacity at the control point of downstream by the average water supply capacity and possible range of water supply capacity suggested by this study. The average water supply capacity is analyzed by the reliability of monthly average water supply capacity. Furthermore, the possible range of water supply capacity is estimated by the standard deviation when water deficit occurs. Therefore, AR (C) is useful to establish and estimate the planning water supply capacity according to the monthly water supply condition and the possible range of water supply capacity when the water supply capacity deficit occurs, South Korea.

• 한국물환경학회지
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• 제24권1호
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• pp.44-53
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• 2008

To recognize the spatial and temporal variability of water temperature and dissolved oxygen in the Youngsan reservoir formed after dike construction, water temperature and dissolved oxygen data have been observed and analyzed from April, 2002 until March, 2003. As the results, certain stratifications were not distinctly observed in the Youngsan reservoir during summer, which was estimated due to the drainage characteristic from the Youngsan water gates. The yearly variation of water temperature in the Youngsan reservoir is shown seasonally ups and downs by the heat exchange between the atmosphere and the reservoir. On the other hand, dissolved oxygen and water temperature in the Youngsan reservoir have been shown inversed proportional correlation. As the calculation results of residence time and water exchange rate, it is considered that the feature of oxygen distribution is determined by the drainage characteristics caused the shortest residence time during summer, which also disturbed the formation of stratification in the Youngsan reservoir.