• 한국환경복원기술학회지
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• 제17권1호
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• pp.173-184
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• 2014

Riparian areas are significant functional grounds for inhabiting ecological system on the river such as the self-regulation of the water quality and the foundation of important corridors. For such functional device to operate, consecutive land purchase scheme that prioritizes targeted areas with high pollutant load rate imposes sustainable development of the ecological riparian belt. The purpose of this study is focused on measuring the methodology for selecting land purchse order before establishing riparian belt in accordance with pollution loading estimation and the basin approach. The Yeongsan and Seomjin river which includes targeted areas of the land purchase have been classified into the large-medium-small(standard basin) influence areas based on their catchment rage, which than sub-divided the research area of Juam lake by 38 small basins and 223 units. Small basins with the high pollution load rates have been assessed as the first prioritized targets. For the second priority, the condition of the point pollutant sources, original area of the targets, original restored area were concerned. The final decision of the land purchase order targeted only those within 50 meter range from the basin. To validate the accumulated data, the on-site investigation went along the targeted zones, which the result shows that all prioritized areas included both point and non-point pollutant sources, and had not a small originally restored areas.

• 한국수자원학회논문집
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• 제39권10호
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• pp.881-890
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• 2006

SWAT 모형을 이용하여 대전 3대 하천 유역의 수문 분석 및 도시화에 따른 영향을 평가하였다. 물수지 분석결과에 의하면, 전체적으로 총 유출량 중 지하수 유출량이 44%정도, 중간 유출량이 6% 그리고 지표유출량이 50%이다. 도시화 영향 분석 결과 전체적으로 1975년에서 2000년까지 갑천유역의 약 5%가량의 도시화는 총 유출량의 변화에 있어서는 현저한 차이를 보이지 않았으나, 도시화 율이 32%정도 증가한 소유역의 경우 유출 성분 분석에서 첨두 유량의 경우 $25{\sim}66%$의 증가를 보였고, 지하수 유출량의 경우 $68{\sim}73%$의 감소를 확인 할 수 있었다. 그리고 도시화의 영향으로 토양수분량은 건기를 제외한 모든 시기동안 감소한 반면 침투량은 모든 시기동안 감소하였다. 도시화의 영향은 강우량이 적고, 증발량이 많은 갈수년에 더 크게 나타났다. 이 결과로부터 도시화의 영향으로 풍수기 동안의 홍수피해 폰가 및 갈수기 동안의 하천의 건천화 문제를 유추 할 수 있을 것이다. 결론적으로 본 연구에서 수행한 수문분석 및 도시화 영향분석 결과는 향후 대천 3대 하천의 생태하천복원을 위한 물순환 정상화 대책마련 및 하천의 유량확보방안 마련을 위한 기초자료로 사용될 수 있을 것이다.

• 한국습지학회지
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• 제21권4호
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• pp.305-311
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• 2019

최근 전 지구적인 기후변화는 예측이 어려운 이상 기후를 발생시키며 기존의 기후에 맞추어 수립된 재해 대응 방안으로는 충분한 방어 및 완화조치가 이루어지지 않고 있다. 특히, 반복되는 집중호우는 견고하게 구성되었던 도심지 홍수방어 체계에서도 피해를 발생시키고 있다. 따라서 본 연구에서는 강우의 공간적인 분포와 도시 특성을 고려하여 유출량의 변화를 분석하였으며, 이는 특정 지역에 집중되는 강우 양상과 불투수층이 많은 도시의 유출특성에 대한 연구이다. 서울 지역에서 한 곳에 집중되는 강우의 경우, 유역의 유입량 및 유출량 계산이 정확하게 이뤄지기 위해서는 유역에 내린 강우를 정확하게 측정해야 한다. 본 연구는 서울 기상청에서 제공 하고 있는 종관기상관측장비(Automated Surface Observing System, ASOS)와 방재 기상관측장비(Automatic Weather Stations, AWS)로 관측된 강우자료를 이용하여 서울 용답 빗물펌프장 유역과 가산1빗물 펌프장 유역에서의 유출량을 EPA-SWMM 모형을 사용하여 산정하고, 비교·분석을 하였다. 빗물펌프장 유역은 불투수 면적이 대부분인 작은 도시 유역이므로, ASOS 자료를 사용할 경우에는 유역과 강우 관측 지점의 거리가 멀어, 유역 내 내린 강우와 상이한 강우 자료를 이용하여 유출량을 계산하게 되는 경우가 많다. 본 연구에서는 유역 근처에 위치한 AWS에서 관측한 강우자료와 유역에서 멀리 떨어진 ASOS에서 관측한 강우자료의 차이를 분석하고, 이에 따라 달라지는 유출량을 계산하였다. 이를 통해 정확한 강우량을 사용하여 빗물펌프장을 운영하거나 도시 홍수 홍수 예보 등을 수행해야 한다는 것을 알 수 있었다. 또한, 본 연구의 결과는 설계강우량 산정 및 유출량 계산에 도움이 될 수 있을 것으로 판단된다.

• 한국농공학회지
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• 제29권4호
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• pp.59-72
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• 1987

Although long-term runoff analysis is important as much as flood analysis in the design of water works, the technological level of the former is relatively lower than that of the latter. In this respect, the precise estimation model for the volume of successive runoff should he developed as soon as possible. Up to now, in Korea, Gajiyama's formula has been widely used in long-term runoff analysis, which has many problems in applying in real situation. On the other hand, in flood analysis, unit hydrograph method has been exclusively used. Therefore, this study aims at trying to apply unit hydrograph method in long-term runoff analysis for the betterment of its estimation. Four test catchment areas were selected ; Maesan area in Namlum river as a representative area of Han river system, Cheongju area in Musim river as one of Geum river system, Hwasun area in Hwasun river as one of Yongsan river system, and Supyung area in Geum river as one of Nakdong river system. In the analysis of unit hydrograph, seperation of effective rainfall was carried out firstly. Considering that effective rainfall and moisture condition of catchrnent area are inside and outside of a phenomenon respectively and the latter is not considered in the analysis, Initial base flow(qb)was selected as an index of moisture condition. At the same time, basic equation(Eq.7) was established, in which qb can take a role as a parameter in relating between cumulative rainfall(P) and cumulative loss of rainfall(Ld). Based on the above equation, computer program for estimation model of qbwas seperately developed according to the range of qb, Developed model was applied to measured hydrographs and hyetographs for total 10 years in 4 test areas and effective rainfall was estimated. Estimation precision of model was checked as shown in Tab- 6 and Fig.8. In the next stage, based on the estimated effective rainfall(R) and runoff(Qd), a runoff distribution ratio was calculated for each teat area using by computerised least square method and used in making unit hydrographs in each test area. Significance of induced hydrographs was tested by checking the relative errors between estimated and measured runoff volume(Tab-9, 10). According to the results, runoff estimation error by unit hydrograph itself was merely 2 or 3 %, but other 2 or 3 % of error proved to be transferred error in the seperation of effective rainfall. In this study, special attentioning point is that, in spite of different river systems and forest conditions of test areas, standardized unit hydrographs for them have very similar curve shape, which can be explained by having similar catchinent characteristics such as stream length, catchinent area, slope, and vegetation intensity. That fact should be treated as important factor ingeneralization of unit hydrograph method.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2017년도 학술발표회
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• pp.181-181
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• 2017

Low impact development (LID) practices has become important to mitigate the damage from natural disasters in urban areas. Thereby many hydrological simulation models can simulate the hydrological impact of LID practices. However, commonly used models are not able to provide specific information to most users such as where LIDs should be placed and what kind of LID should be designed. In this study, a decision support system which can be used with the EPA's SWMM was developed for the determination of LID types and locations of LID practices, named Water Management Prioritization Module (WMPM), was applied to a urbanized university campus. Eight sub-catchments were selected as feasible candidate areas for the planning of LID practices. Pre-designated infiltration trenches and permeable pavements were applied to each selected sub-catchments, followed by peak and total runoffs comparison between before/after planning of LIDs. Moreover, TOPSIS, one of a multi-criteria decision analysis method was used in the procedure of selecting target sub-catchment areas and final prioritization of LID types and locations. As a result, sub-catchments S4 with permeable pavements and S16 with infiltration trenches has shown the most decrease in total and peak runoffs, respectively. Therefore, WMPM was found to be effective in determining the best alternative among various scenarios generated and simulated.

• 한국지형학회지
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• 제25권3호
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• pp.1-18
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• 2018

In Korea, 64% of the land is known as mountain area, but the definition and classification standard of mountain are not clear. Demand for utilization and development of mountain area is increasing. In this situation, the unclear definition and scope of the mountain area can lead to the destruction of the mountain and the increase of disasters due to indiscreet permission of forestland use conversion. Therefore, this study analyzed the variables and criteria that can extract the mountain boundaries through the questionnaire survey and the terrain analysis. We developed a mountain boundary extraction algorithm that can classify topographic mountain by using selected variables. As a result, 72.1% of the total land was analyzed as mountain area. For the three catchment areas with different mountain area ratio, we compared the results with the existing data such as forestland map and cadastral map. We confirmed the differences in boundary and distribution of mountain. In a catchment area with predominantly mountainous area, the algorithmbased mountain classification results were judged to be wider than the mountain or forest of the two maps. On the other hand, in the basin where the non-mountainous region predominated, algorithm-based results yielded a lower mountain area ratio than the other two maps. In the two maps, we was able to confirm the distribution of fragmented mountains. However, these areas were classified as non-mountain areas in algorithm-based results. We concluded that this result occurred because of the algorithm, so it is necessary to refine and elaborate the algorithm afterward. Nevertheless, this algorithm can analyze the topographic variables and the optimal value by watershed that can distinguish the mountain area. The results of this study are significant in that the mountain boundaries were extracted considering the characteristics of different mountain topography by region. This study will help establish policies for stable mountain management.

• 기술사
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• 제30권4호
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• pp.99-116
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• 1997

In order to obtain safe drinking water, free from surface contamination, a study to determine the potential for developing a bank-filtrate system in the Iryong and Yongsan, Nakdong River Basin, Korea was conducted. The main type of aquifer In the study area is alluvial, consisting mostly of sand and gravel. The hydraulic conductivity(k) of the Iryong and Yongsan test areas were 8.63${\times}$10$^-2$cm/s and 9.90${\times}$10$^-2$cm/s, respectively, indicating that these areas are satisfactory for bank filtrate production. Pilot plants(IRPL and YSPL) were set up In Iryong and Yongsan to monitor the change in the quality of bank-filtered water and to determine the effect pumping had on the surrounding hydrogeologic system. The pilot plants operated continuously for about two months and the data obtained were used to validate the groundwater flow model. Computer simulations were conducted to predict the effects of producing bank filtrate using MODFLOW. MODPATH was also linked with the flow model to analyze particle tracking. According to the results of the model simulations and the hydrogeologlc study, long-term pumping, the minimization of drawdown and the availability of uncontaminated sell and groundwater conditions for the catchment area were all Important factors for successful bank-titrate system development.

• 농촌계획
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• 제8권2호
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• pp.42-49
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• 2002

Since legislation of Rural Minor Road Improvement Act 1990, a quarter of its total length had been paved now. However, over 80% of arterial road length(national+provincial roads) had been paved, so, road improvement policy should be focussed on the local road(county+rural minor roads) from now. Generally, in the greater part of coastal plain and island areas, arterial road intensity(total road length/total catchment area) is relatively low, but local road intensity is relatively high. So, in terms of balanced development, much more efforts for rural minor road improvement should be concentrated in coastal plain and islands areas. In Chonnam Province, the maximum differentials of minor rural road improvement ratio was over 20%(the lowest; 14.1% in Goheung, the highest; 35.6% in Goksung) in 1999, but the improvement budget have been allocated in proportion to unpaved road length of each county by the provincial government. However, the differentials should not be fairly narrowed in the near future if the present budget allocation policy be maintained. To solve this problem, target differentials of rural minor road improvement between regions should be set up for each planning year and road improvement budget be allocated according to this policy change.

• 한국수자원학회논문집
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• 제32권5호
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• pp.565-577
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• 1999

프랙탈 기하학은 불규칙적이고 복잡한 자연 현상을 수학적으로 나타낼 수 있는 방법을 제시해 줄 수 있으며, 자기상사성을 가지고 있는 하천의 형상을 비롯한 하도망의 구성은 프랙탈 차원을 가지고 있는 프랙탈 현상이라 할 수 있다. GIUH란 유역의 수문학적 응답인 IUH에 하천의 지형학적인 특성을 적용한 강우-유출 모형으로, Horton의 차수비를 이용하여 지형학적인 특성을 반영할 수 있으며 하천 유역에서 프랙탈 차원은 길이비, 면적비, 분기비 등 Horton의 차수비를 이용하여 산정할수 있다. 프랙탈 GIUH 모형을 제시하였다. 프랙탈 GIUH 모형은 Rosso(1984)가 제시한 GIUH-Nash 모형의 형상계수와 규모계수 등의 매개변수 산정시 유역의 자기상사성을 대변할 수 있는 프랙탈 차원을 직접 적용하였으며, 하천의 길이비와 분기비 만의 함수로 나타내었다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.40-48
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• 2008

The Waimea Basin is located on the northern tip of the South Island of New Zealand. It is a highly productive area with intense water use with multi-stakeholder interest in water. Irrigation from the underground aquifers here makes up the largest portion of used water; however the same aquifers are also the key urban and industrial sources of water. The Waimea/Wairoa Rivers are the main sources of recharge to the underlying aquifers and also feed the costal springs that highly valued by the community and iwi. Due to the location of the main rivers and springs close to the urban centre the water resource system here has high community and aesthetic values. Recent enhanced hydrological modelling work has shown the water resources in this area to be over allocated by 22% for a 1:10 year drought security for maintaining a minimalistic flow of 250 l/s in the lower Waimea River. The current irrigated land area is about 3700 hectares with an additional potential for irrigation of 1500 hectares. Further pressures are also coming on-line with significant population growth in the region. Recent droughts have resulted in significant water use cutbacks and the threat of seawater intrusion in the coastal margins. The Waimea Water Augmentation Committee (WWAC) initiated a three year stage 1 feasibility study in 2004/2005 into the viability of water storage in the upper parts of the catchment for enhancing water availability and its security of supply for consumptive, environmental, community and aesthetic benefits downstream. The project also sought to future proof water supply needs for the Waimea Plains and the surrounding areas for a 50 - 100 year planning horizon. The broad range stage 1 investigation programme has identified the Upper Lee Catchment as being suitable for a storage structure to provide the needs identified and also a possibility for some small scale hydro electricity generation as well. The stage 2 detailed feasibility investigations that are underway now (2007/2008), and to be completed in two years is to provide all details for progressing with the next stage of obtaining necessary permits for construction and commissioning a suitable dam.