• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1176-1181
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• 2006

The purpose of this study was to estimate water supply analysis and reliability indicators by using allocation rule(AR) about Andong Dam and Imha Dam which have parallel reservoirs system. According to the analysis results of allocation rule, for Rule(A) and Rule(B), the contribution of water supply in Andong Dam was 60% more than in Imha Dam, and for Rule(C), the contributions in Andong Dam and Imha Dam were almost equal. In Rule(C), supply is allocated by the ratio which divides the sum of storage and inflow by the mean storage according to the storage state and supply capability state of Andong Dam and Imha Dam. This Rule(C) showed good results in the water supply capability analysis and reliability analysis of parallel reservoirs. In the analysis criteria of water supply in parallel reservoirs system, monthly water change quantity showed better results than monthly constant water quantity in water supply analysis. On the basis of this study, the new technique for water supply analysis was developed to be applied to parallel reservoirs, and this operation rule will establish the efficient operation measures in the application to several kinds of parallel reservoirs system.

• Water for future
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• v.18 no.4
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• pp.347-359
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• 1985

This study aims at the development of DP-Model for the establishment of monthly optimal operation policy of single multi-puppose reservoir by which the water demand of downstream can be satisfied under the various physical constraints. Series, A. B. C. of inflow are selected out of future monthly inflow data which are simulated form the past monthly average inflow of Andong dam site. the neight possible alternatives in each inflow series are established in order that Andong dam can supply the water demand of Nagdong main stream of 30% to 100%. Nextly, the reservoir rule curves is derived for each alternative by the detailed seguential analysis of stroage, future inflow and water demand based on the reservoir continuite equation. Then, and alternative which can satisfy the objective function of system based on the rule curves in the exteream is determined as an optimal operation policy from the application of developed DP=Model.

• Korean Journal of Hydrosciences
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• v.4
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• pp.65-79
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• 1993

Selection of the best operating rule among a set of alternatives for a multipurpose reservoir system operation requires to evaluate many minor criteria in 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 four existing operating rules of the Chungju multipurpose project according to the identified nine multiple criteria. The application results show 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.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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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.

• Journal of Korea Water Resources Association
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• v.38 no.9 s.158
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• pp.761-770
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• 2005

This study applied the fuzzy logic control for the construction of the reservoir operation model which can consider uncertainty of the predicted inflow in determining reservoir release during flood period. The control rule is usually constructed based on the opinion of experts which is a general technique. To improve the drawback of general technique, this study constructed the Fuzzy-Tabu search model automatically established by the fuzzy rule using Tabu search which is a global optimization technique. As the results, the peak release is decreased and the flood control efficiency is improved. The total release is also decreased and this represents the benefit in water use. Consequently, it is confirmed that the effect of flood control can be increased through the constructed model. It also shows that the available water resources after the flood is more increased. So, the proposed Fuzzy-Tabu search model could be better than the actual reservoir operation methodology in the aspect of water use.

• Journal of Korea Water Resources Association
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• v.37 no.6
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• pp.487-497
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• 2004

Adding important new projects such as reservoirs which regulate a river discharge to a river system, existing operation methods should be changed considering these conditions. Since an original operation rule used for an existing system has been designed to be compatible to inputs and outputs of the existing system, the operation rule should be changed to consider the new projects. In this study, the technique of constructing new operation rules considering objectives of both old and new projects is suggested when new project is added to the river system. Reservoir operation rule using both stochastic inflow and optimization technique is developed. As a result of applying the technique to Geum river basin, the efficiency of the technique is verified.

• Journal of Industrial Technology
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• v.3
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• pp.69-74
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• 1983

For the determination of a reservoir capacity Rippl's mass-curve method has long been 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. 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 water-use downstream the waterrelease from the reservoir was determined and with due consideration to the mean inflows and the range of monthly flows the required reservoirs capacity was stochastically determined. It was possible to repersent the so-determined reservoir capacity in terms of the mean monthly inflows and the number of subseries in the determination of ranges. 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.

• Korean Journal of Agricultural Science
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• v.38 no.2
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• pp.331-341
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• 2011

To provide variation of water supply for instream flow from reservoirs with various magnifications of paddy irrigation area to watershed area, 8 reservoirs were selected to draw operation rule curve and to analyze water supplies from reservoirs. Reliability of 90% for supplying irrigation water from reservoir was able to maintain and instream flow water was able to be supplied only in the reservoir with magnification of paddy irrigation area to watershed area above 3. The more magnification of paddy irrigation area to watershed area increased, the more ratio of irrigation water to total water storage decreased, and the more ratio of instream flow water to total water storage increased. From the heightening 113 reservoirs in Korea, annual irrigation water was estimated to 1,146.05 $Mm^3$ in normal operation, 839.57 $Mm^3$ in withdrawal limited operation, and annual instream flow water was estimated to 149.68 $Mm^3$ in normal operation, 283.19 $Mm^3$ in withdrawal limited operation. It was concluded that withdrawal limited operation was followed to have the premise of saving irrigation water, more instream flow water was able to be supplied from reservoirs with high magnification of paddy irrigation area to watershed area.

• Journal of Korea Water Resources Association
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• v.35 no.5
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• pp.501-510
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• 2002

During drought or impending drought period, the reservoir operation method is required to incorporate demand-management policy rule. The objective of this study is focused to the development of demand reduction rule by incorporating hedging-effect for a single reservoir system. To improve the performance measure of the objective function and constraints, we could incorporate three risk performance criteria proposed by Hashimoto et al. (1982) by mixed-integer programming and also incorporate successive linear programming to overcome nonlinear hedging term from the previous study(Shih et al., 1994). To verify this model, this hedging rule was applied to the Daechung multi-purpose dam. As a result, we could evaluate optimal hedging parameters and monthly trigger volumes.

• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.2
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• pp.81-91
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• 1998

Water level of irrigation reservoir during the flood season could be kept to a certain level, so called, flood control level by releasing the flood inflow in advance in order to reduce the peak discharge of next coming flood and the damage of inundation. Concept of restriction intensity of water supply was introduced to evaluate the influence of flood control volume on the irrigation water supply. Restriction intensity can be calculated by multiplying the ratio of restriction to the days of restriction which are obtained from the operation rule curve and daily water level of irrigation reservoir and it has the dimension of % day. The method of restriction intensity was applied to the Yedang irrigation reservoir with the observed data of 30 years to review whether the present flood control volume is reasonable or not, and suggest the optimal flood control volume, if possible.