• 한국수자원학회논문집
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• 제32권6호
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• pp.685-695
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• 1999

홍수예경보란 홍수예측시 적기에 홍수예경보를 발령하여 홍수피해를 경감시키고자 하는 방재활동의 일환으로 이는 홍수조절과정을 전제로 한다. 유역내에서 홍수조절을 직접 수행할 수 있는 곳은 홍수조절용량을 갖추고 있는 다목적 댐으로 홍수시 다목적 댐의 역할은 매우 중요하다고 할 수 있다. 홍수예경보시스템에서 이러한 다목적 댐의 저수지 운영과 관련된 부분의 바로 저수지 운영모듈이다. 본 연구에서는 한강홍수통제소에 구축된 저수지 운영모듈의 현황과 문제점을 고찰하여 한정된 범위내에서 개선작업을 수행하였고 결과적으로 Technical ROM과 ARD ROM을 추가적인 저수지 운영모듈로 구축하였다. 새로이 구축된 저수지 운영모듈을 이용하여 홍수시 한강 홍수통제소는 Technical ROM과 같은 확정론적인 모의방법을 통해 우선 홍수통제에 관한 1차적인 계획을 수립하고, 이후 승인된 방류량에 따라 ARD ROM을 이용하여 최종적인 홍수통제 및 예측 업무를 수행할 수 있을 것이다.

• Water Engineering Research
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• 제3권1호
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• pp.57-62
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• 2002

This research is intended to integrate long-term operation rules and real time operation policy for conservation & flood control in a reservoir. The familiar Yield model has been modified and used to provide long-term rule curves. The model employs linear programming technique under given physical conditions, i.e., total capacity, dead storage, spillways, outlet capacity and their respective elevations to find required and desired minimum storage fur different demands. To investigate the system behavior resulting from the above-mentioned operating policy, i.e., the rule curves, the simulation model was used. Results of the simulation model show that the results of the optimization model are indeed valid. After confirmation of the above mentioned rule curves by the simulation models, gate operation procedure was merged with the long term operation rules to determine the optimum reservoir operating policy. In the gate operation procedure, operating policy in downstream flood plain, i.e., determination of damaging and non-damaging discharges in flood plain, peak floods, which could be routed by reservoir, are determined. Also outflow hydrograph and variations of water surface levels for two known hydrographs are determined. To examine efficiency of the above-mentioned models and their ability in determining the optimum operation policy, Esteghlal reservoir in Iran was analyzed as a case study. A numerical model fur the solution of two-dimensional dam break problems using fractional step method is developed on unstructured grid. The model is based on second-order Weighted Averaged Flux(WAF) scheme with HLLC approximate Riemann solver. To control the nonphysical oscillations associated with second-order accuracy, TVD scheme with SUPERBEE limiter is used. The developed model is verified by comparing the computational solutions with analytic solutions in idealized test cases. Very good agreements have been achieved in the verifications.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.64-67
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• 2006

The main purpose of this research was to investigate the effects of urbanization on the groundwater system in the Gap river basin, a sub-basin of the Geum river basin. In this analysis, we constructed a water cycle analysis system using SWAT. Then, changes in soil moisture and recharge rate due to land-use changes were investigated using different land-use data estimated in 1975 and 2000. Simulation results were analyzed for both draught (2001) and flood (2003) years to take into account different hydrologic conditions. It was shown that recharge rate in the most urbanized area (31% change) was reduced by 17% for both periods due to urbanization. The results also indicated that soil moisture decrease due to urbanization was more sensitive in the drought year (2001) than in the flood year (2003), We expect that the results of this research can contribute to providing useful information for managing urban rivers considering river restoration and flood control.

• 농업과학연구
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• 제48권3호
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• pp.515-526
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• 2021

The frequency of typhoons and torrential rainfalls has increased due to climate change, and the concurrent risk of breakage of dams and reservoirs has increased due to structural aging. To cope with the risk of dam breakage, a more accurate emergency action plan (EAP) must be established, and more advanced technology must be developed for the prediction of flooding. Hence, the present study proposes a method for establishing a more effective EAP by performing flood and inundation analyses using one- and two-dimensional models. The probable maximum flood (PMF) under the condition of probable maximum precipitation (PMP) was calculated for the target area, namely the Gyeong-cheon reservoir watershed. The breakage scenario of the Gyeong-cheon reservoir was then built up, and breakage simulations were conducted using the dam-break flood forecasting (DAMBRK) model. The results of the outflow analysis at the main locations were used as the basis for the one-dimensional (1D) and two-dimensional (2D) flood inundation analyses using the watershed modeling system (WMS) and the FLUvial Modeling ENgine (FLUMEN), respectively. The maximum inundation area between the Daehari-cheon confluence and the Naeseong-cheon location was compared for each model. The 1D flood inundation analysis gave an area of 21.3 km², and the 2D flood inundation analysis gave an area of 21.9 km². Although these results indicate an insignificant difference of 0.6 km² in the inundation area between the two models, it should be noted that one of the main locations (namely, the Yonggung-myeon Administrative and Welfare Center) was not inundated in the 1D (WMS) model but inundated in the 2D (FLUMEN) model.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.539-542
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• 2003

In South Korea, flooding is controlled with large or small reservoirs scattered spatially over the territory. Because recent unexpected hard-rain events requires more flood control capacities, the pre-release system is considered with the most economical alternative. In this case time and volume of discharge should be determined by the simulation. But, existing pre-release simulation system has the problem of specificity. Therefore, GASS is considered to estimate the pre-release time and volume with different configurations of pre-release system. This paper shows that pre-release simulation system could be constructed with arranging GASAtmosphere, GASWatershed, Reservoir, Gate components using GASS. It is also shows that GASS could be used as a foundation for constructing pre-release simulation system that is easy to use and is flexible to reflect the changing configurations of reservoir systems.

• 한국농공학회논문집
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• 제66권1호
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• pp.49-66
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• 2024

Extreme rainfall will become intense due to climate change, increasing inundation risk to agricultural land. Hydrological and hydraulic simulations for the entire watershed were conducted to analyze the impact of climate change. Rainfall data was collected based on past weather observation and SSP (Shared Socio-economic Pathway)5-8.5 climate change scenarios. Simulation for flood volume, reservoir operation, river level, and inundation of agricultural land was conducted through K-HAS (KRC Hydraulics & Hydrology Analysis System) and HEC-RAS (Hydrologic Engineering Center - River Analysis System). Various scenarios were selected, encompassing different periods of rainfall data, including the observed period (1973-2022), near-term future (2021-2050), mid-term future (2051-2080), and long-term future (2081-2100), in addition to probabilistic precipitation events with return periods of 20 years and 100 years. The inundation area of the Aho-Buin district was visualized through GIS (Geographic Information System) based on the results of the flooding analysis. The probabilistic precipitation of climate change scenarios was calculated higher than that of past observations, which affected the increase in reservoir inflow, river level, inundation time, and inundation area. The inundation area and inundation time were higher in the 100-year frequency. Inundation risk was high in the order of long-term future, near-term future, mid-term future, and observed period. It was also shown that the Aho and Buin districts were vulnerable to inundation. These results are expected to be used as fundamental data for assessing the risk of flooding for agricultural land and downstream watersheds under climate change, guiding drainage improvement projects, and making flood risk maps.

• 한국측량학회지
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• 제24권3호
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• pp.299-309
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• 2006

최근 세계적인 기상이변으로 대규모의 자연재해가 발생되고 있으며, 도시지역의 인구 과밀화와 시설물의 대형화로 피해규모도 대형화되고 있다. 본 연구에서는 매미 태풍 시 침수피해가 크게 발생하였던 마산시 월영동지역에 대해 도시홍수량을 추정할 수 있는 SWMM모형을 이용하여 빈도강우와 해수위별 침수예상지를 추정하고 이것을 GIS데이터베이스와 연결하여 침수예상피해를 분석하였다. 그 결과, GIS자료를 이용하여 대상지역을 소유역으로 구분하고 홍수추정모형인 SWMM을 이용하여 침수위치와 침수심을 예측함으로서 빈도강우와 해수위 상승에 따른 침수예상지역을 정확하게 예측할 수 있었다. 또한 침수가 예상되는 지역에 대해 건물용도별로 침수위험도를 예측하거나 침수에 따른 대피계획수립에 이용할 수 있는 자료를 제공할 수 있었으며, 향 후 웹이나 무선통신기술 등과 연계된 재난관리체계구축에 대한 연구가 이뤄질 경우 활용성이 증대될 것으로 판단된다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.44-51
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• 2005

Water flow in rivers during flood season can be 10 to 100 fold higher than normal seasons (low precipitation) in Japan and predicting flood runoff is essential for operating reservoirs with discharging gates. Abundant experiences and knowledge are requisites for operators to be able to make efficient decisions at work. This research investigated a method to transfer technical knowledge by acquiring skills and knowledge from actual dam operators and by using the information to construct an educational training system. The purpose of the research was to enable the execution of a secure and rational reservoir operation during flood period. The educational training system for reservoir operation was developed with the focuses on acquiring knowledge on hydraulics and hydrology and learning about decision making related to the reservoir operation as well as the timing of control. The system is capable of conducting education that corresponds to individual levels in each location. Of the educational training methods, a lecture method that uses textbooks is effective for the understanding of basic knowledge and concepts while a training method that uses a simulation device is essential for the practice of advanced and specialized procedures in specific fields. Simulation devices are used in operational training for airplane flight and driving cars and trains. The educational system presented here was designed to provide further assistance to those who have acquired basic knowledge and concepts through textbooks and also to at low them to perform the satisfactory operation of dam equipment. Our research proposes a method which can realize a system to acquire technical skills-the skills which are the foundation of technical knowledge and operation.

• 한국농공학회논문집
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• 제58권1호
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• pp.39-51
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• 2016

Extreme floods occur more often recently as the frequency of extreme storm events increase due to the climate change. Because the extreme flood exceeding the design flood can cause large-scale disasters, it is important to predict and prepare for the future extreme flood. Flood flow is affected by two main factors; rainfall and land use. To predict the future extreme flood, both changes in rainfall due to the climate change and land use should be considered. The objective of this study was to simulate the future design flood in the Hwangguji river watershed, South Korea. The climate and land use change scenarios were derived from the representative concentration pathways (RCP) 4.5 and 8.5 scenarios. Conversion of land use and its effects (CLUE) and hydrologic modelling system (HEC-HMS) models were used to simulate the land use change and design flood, respectively. Design floods of 100-year and 200-year for 2040, 2070, and 2100 under the RCP4.5 and 8.5 scenarios were calculated and analyzed. The land use change simulation described that the urban area would increase, while forest would decrease from 2010 to 2100 for both the RCP4.5 and 8.5 scenarios. The overall changes in design floods from 2010 to 2100 were similar to those of probable rainfalls. However, the impact of land use change on design flood was negligible because the increase rate of probable rainfall was much larger than that of curve number (CN) and impervious area.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.66-67
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• 2005