• 한국농공학회논문집
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• 제57권5호
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• pp.113-122
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• 2015

This study aims to evaluate future stream flow by the operation of agricultural reservoir group at the upper stream of the Miho River. Four agricultural reservoirs with storage capacities greater than one million cubic meters within the watershed were selected, and the RCP 8.5 climate change scenario was applied to simulate reservoir water storage and stream flow assuming that there are no changes in greenhouse gas reduction. Reservoir operation scenarios were classified into four types depending on the supply of instream flow, and the water supply reliability of each reservoir in terms of water supply under different reservoir operation scenarios was analyzed. In addition, flow duration at the watershed outlet was evaluated. The results showed that the overall run-off ratio of the upper stream watershed of the Miho River will decrease in the future. The future water supply reliability of the reservoirs decreased even when they did not supply instream flow during their operation. It would also be difficult to supply instream flow during non-irrigation periods or throughout the year (January-December); however, operating the reservoir based on the operating rule curve should improve the water supply reliability. In particular, when instream flow was not supplied, high flow increased, and when it was supplied, abundant flow, ordinary flow, and low flow increased. Drought flow increased when instream flow was supplied throughout the year. Therefore, the operation of the agricultural reservoirs in accordance with the operating rule curve is expected to increase stream flow by controlling the water supply to cope with climate change.

• 한국방재학회 논문집
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• 제11권2호
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• pp.147-156
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• 2011

홍수기 다목적댐 운영의 목적은 홍수조절용량을 최대한 이용하여 하류 주요 지점의 첨두홍수량을 저감시키거나, 계획홍수량을 초과하지 않도록 방류량과 방류시점을 조절함으로써 홍수피해규모를 최소화하는 것이다. 따라서 홍수기 다목적댐 운영에 있어 가장 중요한 것은 최적의 방류시점과 방류량의 결정이며 이를 통해 홍수기말 이수용량을 최대로 확보 하는 점이다. 본 연구에서는 다목적 최적화기법의 하나인 goal programming을 이용하여 홍수기 저수지 최적운영을 실시하였다. goal programming은 선형계획법 또는 비선형계획법을 이용하여 두 개 이상의 목적을 가진 문제의 최적 대안을 구하기 위해, 목표값으로부터의 편차의 합을 최소화하여 최적화하는 기법이다. 홍수기 다목적댐 운영에서 goal programming의 적용성을 검토하기 위해 실제 홍수 사상을 이용하여, 단일저수지 운영과 저수지 연계운영을 실시하였다. 단일저수지 운영을 적용하기 위한 시험유역으로는 충주댐 유역을 선정하였고 저수지 연계운영을 적용하기 위한 시험유역으로는 안동댐과 임하댐 유역을 선정하였다. goal programming의 결과 분석을 위해 저수지 모의운영 모형인 HEC-5 모형의 결과와 비교, 분석하였다. 검토 결과 goal programming을 이용할 경우 홍수기 말에 저수지 수위를 홍수기제한수위로 유지할 수 있었으며 주요 지점의 홍수량을 매 시간 적절히 계획홍수량 아래로 유지할 수 있었다. goal programming을 이용한 최적 운영의 경우 전 구간의 유입량을 알고 있다고 가정한 점에서 실제 저수지 운영과는 차이가 있으나, 적절한 제약조건을 적용하고 홍수예경보를 이용하여 예보된 유입량을 활용하면 최적의 방류량 시점과 방류량을 산정하여 홍수기 다목적댐을 효율적으로 운영할 수 있으며 주요 지점의 홍수량도 저감할 수 있을 것으로 판단된다.

• 한국수자원학회논문집
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• 제33권6호
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• pp.733-744
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• 2000

불확실한 저수지 유입량과 수요량 때문에 최적의 저수지 조작기준은 정량화하기 쉽지 않다. 그렇지만 저수지 조작에 일정 수요를 충족시키면서 모의 발생시킨 유입량 시계열을 반영함으로써 음해 추계적 최적화 접근법을 이용하면 조작기준은 작성 가능하다. 이에 본 연구에서는 한강수계 7개 저수지 계통에 적절하도록 수력발전 최대화를 선형추적으로 모형화하고 최적제어를 이용하여 최적조작을 수행하였다. 이 때 2001년 수도권 용수수요를 만족시키도록 한 최적 조작 모형에는 다지점 마코브 모형에 의해 모의 발생된 유입량 자료가 입력된다. 그리고 최적 결과에 대하여 회구 분석과 통계 분석을 수행하여 월별 조작기준을 작성하고 계절별 저수위별 확률을 제시하였다. 이때 상대적으로 저수용량이 커서 조절능력이 좋은 화천댐, 소양강댐, 충주댐은 저류와 방류의 회귀 관계가 잘 형성되었다. 작성된 조작기준으로 실제 운영 기간동안에 대하여 모의조작을 수행하여 그 효율성을 검증하였다.

• 한국농공학회지
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• 제33권4호
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• pp.45-51
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• 1991

The objective of this paper is to show how the fuzzy sets theory can be applied to the reservoir operation guidelines for agricultural purposes. The concepts of the theory has been resented as a new tool for the decision problems which contains fuzziness and it's application can be found in operations research, expert systems, robotics, fuzzy computers, and pattern recognition. The fuzzy control system for the reservoir operation composed of a set of reservoir operation rules and a fuzzy inference engine was built. Water demand for paddy fields, water availability, and inflow to a reservoir were selected as main factors which determine the magnitude of reservoir release. The behavior of the control system was evaluated for different level of water demand and the results seemed to be reasonable.

• 한국농공학회논문집
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• 제53권1호
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• pp.17-28
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• 2011

This study was performed to ascertain the possibility of securing inflows to reservoir with low ratio of watershed to paddy field areas by outside diversion weir. The case of Maengdong reservoir and Samryong diversion weir was selected. Most of inflows to Maengdong reservoir with watershed area of $7.06\;km^2$ and total storage capacity of $1,269{\times}10^4\;m^3$ are filled with intake water from outside Samryong diversion weir. Only using water storage data in Maengdong reservoir from 1991 to 2009, the range of water intake in Samryong diversion weir to Maengdong reservoir was optimized to 0.135~30 mm/d, from which water intake to Maengdong reservoir was $1,672.9{\times}10^4\;m^3$ (70.1 %) and downstream outflow to Weonnam reservoir was $714.4{\times}10^4\;m^3$ (29.9 %). The parameters of DAWAST model for reservoir inflow were determined to UMAX of 313.8 mm, LMAX 20.3 mm, FC 136.8 mm, CP 0.018, and CE 0.007. Inflows to Maengdong reservoir were $427.1{\times}10^4\;m^3$ (20.3 %) from inside watershed, and $1,672.9{\times}10^4\;m^3$ (79.7 %) from outside. Paddy irrigation water requirements were estimated to $1,549{\times}10^4\;m^3$ on annual average. Operation rule curve was drawn by using daily inflow and irrigation requirement data. By securing the amount of inflow to Maengdong reservoir to about 80 % from outside Samryong diversion weir, water supply capacity for irrigation of $1,549{\times}10^4\;m^3/yr$ was analyzed to be enough. Additional water supplies for instream flow were analyzed to $1,412\;m^3/d$ in normal reservoir operation, $36,000\;m^3/d$ in withdrawal limit operation by operation rule curve from October to March of non irrigation period.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.486-492
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• 1999

One of the purpose of the reservoir operation is minimizing theinnudation area in the downstream reaches during flood period.l To execute the gate operation properly , it requires lots of real-time data such as rainfall, reservoir level, and water level in the downstrea. Gate operation model was developed with the flood discharge obtained from real-time flood forecasting model and the criterion prepared from the past history of gate operation. Water level in the downstream would be increased by the releasing discharge from the spillway and the area of paddy land flooded in a certain detph and time would be estimated usnig GIS map. Gate operation model was applied to the Yedang reservoir, and the flooded area, depth and time in the paddy land was estimaged.

• 한국농공학회지
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• 제30권3호
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• pp.95-105
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• 1988

This study refers to the development of a hydrologic model simulating daily inflow and release rates for irrigation 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 or this study is to develop a Daily Irrigation Reservoir Operation Model(DIROM) combining the inflow and the release models which depicts the daily water level fluctuations of an irrigation reservoir, and to evaluate the applicability of the model. DIROM was applied to four reservoirs and daily water levels were simulated and compared to the observed data. The model behaviour was also compared with that of a ten - day based model, Reservoir Operation Study(ROS) which has been applied for determining the design capacity of reservoirs. Various combinations of measured and simulated inflow and release rates for tested reservoirs were used to define the daily water level fluctuations. Simulated release rates and measured inflow data resulted in larger errors, and simulated inflow and release rates produced the smallest errors in water level comparison. Two resevoir operation models, DIROM and ROS were applied to the same reservoir and the simulation results compared. The computational errors of DIROM ware smaller than those of ROS, and DIROM was more sensitive to meteorological conditions. DIROM demonstrated its potenial applicability in water management and operation.

• 대한토목학회논문집
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• 제32권4B호
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• pp.221-232
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• 2012

본 연구에서는 이상홍수 발생 시 저수지의 안전성을 확보함과 동시에 두 개의 저수지를 효율적으로 연계운영하여 하류의 홍수피해를 줄이기 위한 모형을 개발하였다. 이상홍수 발생 시 저수지 최적연계운영을 위해 선형계획법을 사용하였고, 저수지 운영에서 유입량, 저수지 수위, 유입량의 증감 등의 요소에 포함된 불확실성을 해결하기 위해 퍼지제어기법을 도입하였다. 선형계획법을 이용하여 이상홍수 유입에 따른 저수지 최적연계운영규칙을 찾아내고, 퍼지제어기법을 사용하여 신속하고 정교한 운영이 요구되는 이상홍수 유입상황에 사용할 수 있는 모형을 개발하였다. 본 연구에서는 낙동강 상류에 위치한 안동댐과 임하댐을 대상으로 각 댐의 저수지에 100년 빈도의 홍수와 PMF가 유입될 때 안동시의 계획홍수량을 초과하지 않도록 저수지최적연계운영을 실시하였고, 최적연계운영규칙과 퍼지제어기법을 사용하여 댐 하류지점의 유량과 각 댐별 저류량, 유입량, 유입량의 증감에 따라 방류량을 결정하는 모형을 개발하였다. 개발된 모형은 안동댐과 임하댐의 각 저수지 및 안동시의 유황에 따라 결정되는 224개의 퍼지규칙으로 정리되었으며, GUI를 통해 현재 유황을 입력하면 각 댐의 방류량을 간단히 결정할 수 있다.

• 경영과학
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• 제29권1호
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• pp.1-14
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• 2012

The goal of the multi-reservoir operation planning is to provide an optimal release plan that maximize the reservoir storage and hydropower generation while minimizing the spillages. However, the reservoir operation is difficult due to the uncertainty associated with inflows. In order to consider the uncertain inflows in the reservoir operating problem, we present a Stochastic Dynamic Programming (SDP) model based on the markov decision process (MDP). The objective of the model is to maximize the expected value of the system performance that is the weighted sum of all expected objective values. With the SDP model, multi-reservoir operating rule can be derived, and it also generates the steady state probabilities of reservoir storage and inflow as output. We applied the model to the Geum-river basin in Korea and could generate a multi-reservoir monthly operating plan that can consider the uncertainty of inflow.

• 한국물환경학회지
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• 제22권6호
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• pp.1088-1093
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• 2006

In this study, the method of annual sediment estimation for reservoir long-term operation is proposed. Long-term daily precipitation and evaporation are predicted by Markov Chain. Using these values, reservoir inflow is simulated by NWS-PC model. Reservoir sediment load is estimated by sediment rating relation curve which is observed. From the simulation results, it was found that each simulated value by Markov Chain and NWS-PC was well compared to the observed ones and also estimated reservoir sediment was appropriate to the compared values using empirical equations. It is thought that the proposed method for estimation of reservoir sediment can be useful used to operate the reservoir.