• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.232-232
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• 2015

Land use and climate changes are the important factors to determine the runoff and sediment loads from the watershed. The changes also affected to runoff volume/pattern to the dam operation and may cause flood and drought situations in the downstream area. Sirikit Dam is one of the biggest dams in Thailand which cover about 25 % of the runoff into the Central Plain where the Bangkok Capital is located. The study aims to determine the effect of land use change to the runoff/sediment volume pattern and the rainfall-runoff-sediment relationship in the different land use type. Field measurements of the actual rainfall, runoff and sediment in the selected four sub-basins with different type of land use in the Upper Nan Basin were conducted and the runoff ratio coefficients and sediment yield were estimated for each sub-basin. The effect of the land use change (deforestation) towards runoff/sediment will be investigated. The study of the climate change impact on the runoff in the future scenarios was conducted to project the change of runoff volume/pattern into the Sirikit Dam. The improvement of the Sirikit Dam operation rule was conducted to reduce the weakness of the existing operation rules after Floods 2011. The newly proposed dam operation rule improvement will then be evaluated from the water shortage situations in the downstream of Sirikit Dam under various conditions of changes of both land use and climate when compared with the situations based on the existing reservoir operation rules.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.106-106
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• 2021

라오스 남능강 유역에는 현재 11개의 수력 발전 댐이 운영되고 있으며 최근에 설치된 댐을 제외하고는 오래전에 개발된 운영규정 곡선에 근거하여 운영하고 있다. 즉 댐의 증설에 따른 하천 유량의 변동과 발전소의 설비용량증설 등의 발전환경이 충분히 반영되지 못한 상태로 운영하고 있으며, 이로 인해 통합수자원 관리의 최적화 차원의 일환으로 최대 전력생산을 위한 새로운 저수지 운영규정 곡선 개발이 필요하게 되었다. 저수지 운영규정 곡선(reservoir operation rule curve)은 일반적으로 주어진 저수지의 규모와 저수지로의 유입량 그리고 발전소의 설비용량 등의 발전환경을 종합적으로 고려하여 연간 발전량을 최대로 생산할 수 있도록 최적화 기법 등을 활용하여 개발한다. 본 고에서는 이를 위해 범용적인 동적 계획법(Dynamic Programming:DP)프로그램인 CSUDP를 활용하여 최초의 최적 저수지 운영규정 곡선을 제시하고 이에 의한 발전량을 모의하기 위해 HEC-ResSim package를 활용하였으며, 최종적으로는 기존의 운영규정 곡선, 운영실적, 그리고 현장 운영자의 의견 등을 종합적으로 고려하여 댐 운영 시나리오(단독, 연결, 댐별 상업 발전 시기 등)별로 운영규정 곡선을 개발하고 라오스 정부(EdL)에 제시하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.837-841
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• 2010

농업용 저수지는 주로 관개용수를 공급하는 역할을 해 왔으나 4대강 살리기 사업의 저수지 둑 높이기로 확보한 저수량을 이용하여 하류하천의 유지유량 공급과 홍수조절용량으로 이용하기 위한 저수지의 운영률 설정을 요구하고 있다. 관개용수를 공급하면서 하천유지유량을 상시공급, 유량부족시 공급, 30일, 60일, 90일 집중 공급 등 시나리오별 공급효과와 홍수기 홍수조절용량을 단계별로 설정하여 각 운영효과를 분석해 저수지 운영률을 합리적으로 설정할 수 있는 방법을 검토하였으며, 탑정저수지와 미호저수지에 대해 적용한 사례를 제시하였다.

• Journal of Korea Water Resources Association
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• v.37 no.5
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• pp.353-361
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• 2004

Effective storage in agricultural reservoir has been determined through the reservoir simulation operation based on the water budget analysis. Since each watershed has the native property for runoff, considering the runoff yielding from the basin is feasible to the determination of reservoir effective storage. In this study the stochastic linear programming model considering mainly runoff from watershed has been also formulated to analyze the effective storage of the exiting reservoir. The linear decision rule coupled with chance-constrained model in the linear programming model contributes to reduce the size of linear program model without considering the period of analysis. The Geum-Gang reservoir located in Ansung have been adopted to evaluate the effective storage. It has been shown that the effective storage based on the linear programming model is greater than that based on the water budget analysis. It has been also desired that once the effective storage is obtained through the linear programming model, operation of the reservoir should be performed to check the designed capacity.

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.106-108
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• 1987

Until now, inflow has been handled an independent log-normal random variable in the problem of planning the long-term operation of a multi-reservoir hydrothermal electric power generation system. This paper introduces the detail study for making rule curve by applying weekly time interval for handling inflows. The hydro system model consists of a set of reservoirs and ponds. Thermal units are modeld by one equivalent thermal unit. Objective is minimizing the total cost that the summation of the fuel cost of equivalent thermal unit at each time interval. For optimization, stochastic dynamic programming(SDP) algorithm using successive approximations is used.

• Journal of Environmental Science International
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• v.14 no.6
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• pp.533-542
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• 2005

In this study, an optimization technique was developed from the application of Allocation Rule. Average Allocation coefficients of the Andong and Imha dam compare constant water supply condition with vary water supply condition that are above the contribute ratio $67\%\~50\%$ the Andong dam in Rule(A)-Rule(C). In the Refill Season, Andong dam water supply contribution is higher than Imha dam at the Control point water supply. In the Allocation analysis results, Rule(A) is calculated storage ratio because Andong dam contribute to Control point larger than Imha dam which Andong dam storage is larger than Imha dam storage. Rule(B) calculated sum of the storage and inflow ratio for Andong dam and Imha dam, as Andong dam contribution is higher than Imha dam. Rule(C) calculated that sum of storage, inflow and water supply is divided average storage ratio, as the best results of the Allocation coefficients and water supply capacity. The results of storage analysis is larger vary water supply condition than constant water supply condition and the results of water supply analysis is larger vary water supply condition than constant water supply condition. Water supply deficit is decrease $30\%$ for vary water supply condition.

• Water for future
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• v.25 no.1
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• pp.83-92
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• 1992

Selection of the best operation rule among a set of alternatives for a multipurpose reservoir system operation requires to evaluate many minor criteria I n addition to the major objectives assessed to the system, These problems are sufficiently complex and difficult that they are beyond heuristic decision rules and experiences in case several noncommensurable multiple criteria are included in the evaluation. With the assistance of multicriterion decision analysis techniques, it is possible to select the best one among various alternatives by systematically comparing and ranking the alternatives with respect to the criteria of choice. Evaluation criteria for multipurpose reservoir system operating rules were identified and defined, and the multicriterion decision analysis techniques were applied to evaluate the fore developed operating rules of the existing Chungju multipurpose project according to the identified nine multiple criteria. The application result shows that the methodology is very efficient to select the best operation alternative among a finite number of operating rules with many evaluation criteria for a large scale reservoir system operation.

• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.1
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• pp.33-40
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• 1992

Up to now, monthly water balance analysis has been dominantly used for the water resources planning. But, it is more reasonable to explain the variation of spatial and temporal distribution of water by the daily water balance model with daily streamflow data. Since we are recently facing the problems of regional unbalance of water quantity, and of multiuse of irrigation water, and of deterioration of water quality, it is urgently needed to develop the daily water balance model to solve those problems and establish the rational plannings of agricultural water resources. In the circumstances, Daily water Balance(DAWABA) model for irrigation reservoirs was developed and the operation rule of irrigation resorvoir during drought season was established.

• Water for future
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• v.19 no.2
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• pp.149-156
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• 1986

The generated sequences of monthly flows were analyzed based on the range concept. With the optimum operation rule of the reservoirs as the one which maximizes the wateruse downstream the waterrelease from the reservoir was determined and with \ulcorner consideration to the mean inflows and the range of monthly flows the required reservoirs capacity was stochastically determind. It is suggested that the result obtained in this study would be applied to approximately estimate, in the stage of preliminary design, the required capacity of a reservoir in question with the limited information such as the mean monthly inflow and the period of reservoir operation. For the determination of a reservoir capacity Rippl's mass-curve method has been long used with the past river flow data assuming the same flow records will be repeated in the future. This study aims to find out a better method for determining the reservoir capacity by employing the analytical theory based on the stochastic process. For the present study the synthetic generation methods of Thomas-Fiering type was used to synthetically generate 50 years of monthly river inflows to three single-purpose reservoirs and three multi-purpose reservoirs.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.2B
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• pp.93-101
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• 2012

HEC-ResSim, reservoir operation model, is applied to Seomjin river dam in order to establish a rational method for water supply and flood control by dam operation. In order to minimize downstream flood damage for Seomjin river basin and adjacent regions, reservoir routing is applied to several frequency flood events within the framework of rainy seasonal operation rule and then the characteristics change of hydrological behavior for the downstream of study area is investigated in depth. Its quantitative efficiency and estimation method is evaluated on the basis of the adjustment scheme of conservation water surface elevation for flood control and water secure; reservoir routing considering preliminary release and variable restricted water level; and its effect to water supply; and downstream flood-duration analysis.