• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2010년도 학술발표회
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• pp.122-126
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• 2010

This paper elaborates on difficulties when ones tried to apply domestically developed technology to other countries from both technical and sociological aspects. Next, the author proposes possible solutions to expand the applicability of domestic technology. The main one is breaking down a technology to smaller components so that anybody can clarify the applicability of each component. The author presents an example of this methodology to flood hazard mapping.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.36-36
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• 2023

Sedimentation is a natural process that occurs in all reservoirs. Sedimentation problem reduces the storage capacity of the reservoir and limits its ability to provide water for various uses, such as irrigation, hydropower generation, and flood control. Therefore, predicting reservoir sedimentation is important for ensuring the efficient operation and sedimentation management of a reservoir and . In this study, the HECRAS model was applied to predict longitudinal distribution of deposited sediment in the Pleikrong reservoir to 2050. Different scenarios was considered: (i) no climate change, (ii) climate change (under two emissions scenarios, RCP4.5 and RCP8.5), and (iii) climate change and land use change (followed land use planning of the watershed). The computation results with different scenarios were analyses and compared. The results show that the reservoir reduced storage volume's rate and sedimentation proceed toward to the dam in the case of climate change is faster than in the case of no climate change. Analyses also indicates that following the land used planning could also improve the long-term problem of the reservoir sedimentation. The outcomes of this study will be helpful for a sustainable plan of sediment management for the Pleikrong reservoir.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2019년도 학술발표회
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• pp.149-149
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• 2019

Gross Primary production (GPP) and evapotranspiration (ET) are the two critical components of carbon and water cycle respectively, linking the terrestrial surface and ecosystem with the atmosphere. The ratio between GPP to ET is called ecosystem water use efficiency (EWUE) and its quantification at the forest site helps to understand the impact of climate change due to large scale anthropogenic activities such as deforestation and irrigation. This study was conducted at the FLUXNET forest site CN-Qia (2003-2005) using Community land model (CLM 5.0). We simulated carbon and water fluxes including GPP, ecosystem respiration (ER), and ET using climatic variables as forcing dataset for 30 years (1981-2010). Model results were validated with the FLUXNET tower observations. The correlation showed better performance with values of 0.65, 0.77, and 0.63 for GPP, ER, and ET, respectively. The model underestimated the results with minimum bias of -0.04, -1.67, and -0.40 for GPP, ER, and ET, respectively. Effect of climate 'CLIM' and '$CO_2$' were analyzed based on EWUE and its trend was evaluated in the study period. The positive trend of EWUE was observed in the whole period from 1981-2010, and the trend showed further increase when simulated with rising $CO_2$. The time period were divided into two parts, from 1981-2000 and from 2001 to 2010, to identify the warming effect on EWUE. The first period showed the similar increasing trend of EWUE, but the second period showed slightly decreasing trend. This might be associated with the increase in ET in the wet temperate forest site due to increase in climate warming. Water use efficiency defined by transpiration (TR) (TWUE), and inherent-TR based WUE (IT-WUE) were also discussed. This research provides the evidence to climate warming and emphasized the importance of long term planning for management of water resources and evaporative demand in irrigation, deforestation and other anthropogenic activities.

• 상하수도학회지
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• 제34권5호
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• pp.373-383
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• 2020

The purpose of this study was to evaluate the corrosion damage of large diameter metallic pipes buried in reclaimed land due to the corrosion effect by soil, and to propose a method of installing metal pipes in the reclaimed land. The results are as follow. First, the soil of the reclaimed land was gray clay, the soil specific resistance indicating soil corrosiveness was at least 120 Ω-cm, the pH was weakly acidic(5.04 to 5.60), the redox potential was at least 62 mV, the moisture content was at most 48.8%, and chlorine ions and sulfate ions were up to 4,706.1 mg/kg and 420 mg/kg. Therefore, the overall soil corrosivity score was up to 19, and the external corrosion effect seems to be very large. Second, the condition of straight part of pipes was in good condition, but most of KP joints were affected by corrosion at a severe level. The reason for this seems to be that KP joints accelerated corrosion due to stress and crevice corrosion in addition to galvanic corrosion in the same environment. Third, as a result of evaluating correlations of each item that affects the corrosion on the external part, the lower the soil resistivity and redox potential, the greater the effect on the KP joints corrosion, and the moisture content, chloride ion, and sulfate ion, the higher the value, the greater the effect on the corrosion of KP joints. In addition, among soil corrosion items, the coefficient of determination of soil resistivity with corrosion of KP joints was the highest with 0.6439~0.7672. Fourth, when installing metal pipes or other accessories because the soil of the reclaimed land is highly corrosive, it is necessary to apply a corrosion preventive method to extend the life of pipes and prevent leakage accidents caused by corrosion damage to the joint.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.383-383
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• 2005

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2004년도 학술발표회
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• pp.1271-1275
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• 2004

The purpose of this study is to present a standardized scheme for providing agriculture-related information at various spatial resolutions of satellite images including Landsat +ETM, KOMPSAT-1 EOC, ASTER VNIR, and IKONOS panchromatic and multi-spectral images. The satellite images were interpreted especially for identifying agricultural areas, crop types, agricultural facilities and structures. The results were compared with the land cover/land use classification system suggested by Ministry of Construction & Transportation based on NGIS (National Geographic Information System) and Ministry of Environment based on satellite remote sensing data. As a result, high-resolution agricultural land cover map from IKONOS imageries was made out. The results by IKONOS image will be provided to KOMPSAT-2 project for agricultural application.

• 한국수자원학회논문집
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• 제52권spc2호
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• pp.791-799
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• 2019

본 연구는 보가 다수 분포하고 있는 만경강을 대상으로 항공사진(1948, 1967, 1973, 1989, 2010)을 이용하여 서식처 유형을 분류하고, 시간에 따른 서식처 구조 변화를 설명하였다. 서식처 구조는 지형과 하도서식처 중 물이 있는 서식처로 구분되었으며, 지형은 나지, 식생부, 수면부, 경작지, 교란지로 분류하였으며, 하도서식처는 자연여울, 인공여울, 평여울, 머리완도, 꼬리완도, 중앙완도, 못, 첩수로로 구분하여 면적을 산출하여 백분율로 비교하였다. 1970년대 골재채취와 1980년대 보 설치로 인하여 나지는 소멸되고 수면부와 식생부는 급격히 증가함에 따라, 평여울은 급격하게 감소한 반면, 흐름이 다소 정체되어 습지와 유사한 중앙완도 서식처의 비율은 급격하게 증가하였다. 또한, 나지와 식생부 위에 존재하는 머리완도, 꼬리완도, 못과 같은 서식처는 보 설치 이후 사라지거나 일부만 남아있다. 본 연구는 생태적인 하천관리를 위한 기초자료로서 향후 교란에 따른 하천 환경의 잠재력을 파악하는데 기초자료로 이용할 수 있을 것으로 판단된다.

• 한국수자원학회논문집
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• 제45권8호
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• pp.805-814
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• 2012

대부분의 수문자료는 지상관측을 통해 얻어진다. 그러나 어떤 지역은 접근이 어렵거나 장기적인 관측에 어려움이 있기 때문에 지상관측을 대체하거나 보완할 새로운 방법이 요구된다. 시 공간적 한계를 극복할 수 있는 대안으로 미항공우주국 NASA에서 2002년 지구 중력장을 측정하는 GRACE(Gravity Recovery And Climate Experiment) 인공위성 자료가 존재한다. 본 연구에서는 GRACE Level-2 중력자료를 이용하여 공간평활화 반경별(0 km, 300 km, 500 km)로 한반도의 수자원변화량(GRACE-based TWSC)을 산정하였다. 산정된 결과의 타당성을 검증하기 위해, 지상 수문 관측자료를 이용한 수자원 변화량(land-based TWSC)과의 비교를 시도하였다. Land-based TWSC는 WAMIS의 강우량, 증발 산량 및 GLDAS의 유출량 자료를 이용해 계산하였다. GRACE-based TWSC와 land-based TWSC의 RMSE 검정 결과, 공간평활화 반경 500 km의 위성자료가 한반도에 가장 적합한 것으로 나타났다. 한반도의 월별 평균 TWSC는 0.986 cm/month로 나타났고, 이러한 큰 변화폭 때문에 안정적수자원 확보를 위한 대처 방안의 마련이 필요한 것으로 평가된다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2021년도 학술발표회
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• pp.204-204
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• 2021

Terrestrial water storage (TWS) includes all components of water (e.g., surface water, groundwater, snow and ice) over the land. So accurately predicting and estimating TWS is important in water resource management. Although many land surface models are used to predict the TWS, model output has errors and biases in comparison to the observation data due to the model deficiencies in the model structure, atmospheric forcing datasets, and parameters. In this study, Gravity Recovery And Climate Experiment (GRACE) satelite TWS data is assimilated in the Community Land Model version 5 with a biogeochemistry module (CLM5.0-BGC) over East Asia from 2003 to 2010 by employing the Ensemble Adjustment Kalman Filter (EAKF). Results showed that TWS over East Asia continued to decrease during the study period, and the ability to simulate the surface water storage, which is the component of the CLM derived TWS, was greatly improved. We further investigated the impact of assimilated TWS on the vegetated and carbon related variables, including the leaf area index and primary products of ecosystem. We also evaluated the simulated total ecosystem carbon and calculated its correlation with TWS. This study shows that how the better simulated TWS plays a role in capturing not only water but also carbon fluxes and states.

• 한국수자원학회논문집
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• 제33권S1호
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• pp.11-19
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• 2000

The role of river in the global water cycles and the modelling the horizontal water transport by rivers in the global scale are discussed. Due to the consolidation of the various hydrological information of the planet, now it is possible to monitor and simulate the quantity of the water carried by rivers. Land surface models that were developed originally for giving the boundary condition of the atmospheric and/or climatic models can be fairly used for river runoff simulations at least monthly scale, and it is promissing the approach will be a powerful tool to investigate the future water resources management.