• Title/Summary/Keyword: river basin

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Primary Ecological Effect Analysis of Emergent Water Transportation in the Lower Reaches of Tarim River Based on RS Technology

  • Xu, Mei;Huang, ShiFeng;He, Yu
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1301-1303
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    • 2003
  • Tarim River is the biggest inland river in China, its problem of eco-environment is worsening in the lower reach. For keeping this trend within limits, the measure of emergent water transportation to the lower reach was taken. In this paper, the remote sensing technology will be applied to the analysis of eco-environment effect after water transportation. The result is: the vegetation index and cover ratio increased but not markedly, the eco-environment situation can't been improved obviously up to now. It is some effective but temporary . The continuity, quality and quality of water source for the Tarim River must been ensured.

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A Study on the River Discharge Measurement Techniques (하천유량 측정기법에 관한 연구)

  • 김성원;지홍기
    • Journal of Environmental Science International
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    • v.7 no.6
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    • pp.793-801
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    • 1998
  • In this study, the Dilution Method is used to measure river discharge through the hydraulic model test. the dilution method is divided into Constant-Rate-Infection Method and Slug-Injection Method in the river discharge measurement techniques. When the dilution method is applied in the hydraulic model flume, it is analyzed that the estimated error of constant-rate-injection method is less than that of the slug-in-jection method, and the result shows that floodflow analysis is more efficient than lowflow analysis as compared observed discharge with calculated discharge. The result of statistical error analysis shows that the constant-rate-injection method is appropriate technique for the measurement of the river discharge. Therefore, the dilution method among the river discharge measurement techniques can be applied for the river basin which can't be measured with current meter or unsteady-flow regime in the urban-small drainage or hydraulic structure equipment area and can be obtained more exact results than any other discharge measurement techniques.

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Diffusive Estimation of the Conservative Contaminant in River Estuary (하구의 보존성 오염물질 확산 예측)

  • Yoon, Jong-Su;Shin, Chan-Ki;Hwang, Dong-Jin
    • Journal of environmental and Sanitary engineering
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    • v.23 no.3
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    • pp.47-57
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    • 2008
  • This study was predicted the diffusion of the conservative contaminant using a two-dimensional hydraulic model. The research area is upper basin of Jakwang river where the possibility where the pollutant of vast quantity will flow is high. Using SMS model, we calculated two-dimensional stream flow. And using this result, predicted the conduct of the conservative contaminant by pollutant transfer diffusion calculation. And also we predicted flow and contaminant diffusion in the near estuary by constructed guide bank. As a result of study, pollutant effect scope of the conservative contaminant was predicted with the fact that will broaden because of interception by guide bank. As discharge was increased from the Jakwang river, The diffusion of the pollutant is accelerated, also the effect scope increases.

Assessment of Trophic State of Large Reservoir for Agriculture in Kum River Basin Using Remote Sensing (원격탐사를 이용한 금강수계 대형 농업용 저수지의 영양상태 평가)

  • Kim, Tae Keun
    • Journal of Korean Society for Geospatial Information Science
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    • v.9 no.1 s.17
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    • pp.19-25
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    • 2001
  • Satellite remote sensing, with its synoptic coverage, is used to evaluate the trophic state of large reservoir for agriculture in Kum River basin. The prediction model for chlorophyll-${\alpha}$ which was derived from Daecheong reservoir was applied to four LANDSAT TM imageries to generate a distribution map of trophic state. The chlorophyll-${\alpha}$ model was found to be reasonably reliable predictors for average trophic state value of reservoir. LANDSAT TM imagery data appears to have great utility in assessing trophic state of reservoir.

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A Generation of Synthetic Monthly Streamflows in the Han River Basin by Disaggregation Model (한강수계에 있어서 분해모형에 의한 모의 월유량 발생)

  • 강관수;선우중호
    • Water for future
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    • v.20 no.2
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    • pp.107-116
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    • 1987
  • The stochastic model has been developed for synthetic generation of hydrologic series that would be needed in the analysis, planning, design and operation of water resources system. In this study, after generating the yearly streamflows by multisite AR(1) model using the historical data in the Han River Basin, the monthly streamflows is generated by the disaggregation model. The model is verified of its applicability to domestic rivers, which is obtained through the statistical analysis and good ness of fit test using synthetic streamflows generated.

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A study on Average CN Estimation in River Basin using Satellite Data

  • Kwon, Bong-kyum;Jo, Myung-Hee;Ahn, Seung-Sep;Kiyoshi, Yamada
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.499-499
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    • 2002
  • The goal of this study is to apply and evaluate the precipitation outflow in river basin using satellite data and GIS for proposing the efficient watershed management method. Not only precipitation outflow data but also various spatial data such as digital map, soil map, geologic map and multi-temporal TM images were used. Using landcover classification result and soil map were applied to estimate the average CN. The CN value of 63.37 by SCS method was produced in AMC-2 condition otherwise the result of direct estimation with observation method was 63 CN value. The relative error of two results was 0.59%. It can be possible to apply the satellite data for precipitation outflow analysis. For more accurate and credible analysis of this, the more multi-temporal satellite and real observation data will be needed.

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A Study of Probability Functions of Best Fit to Distribution of Annual Runoff -on the Nakdong River Basin- (년유출량의 적정확률 분포형에 관한 연구 -낙동강 유역을 중심으로-)

  • 조규상;이순탁
    • Water for future
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    • v.7 no.2
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    • pp.107-111
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    • 1974
  • Annual runoff in the Nakdong river basin has been analyzed to find the probability functions of best fit to distribution of historical annual runoff. The results obtained are as follows; (1) Log-normal 3-parameter disrtibution is believed as the probability function of best fit to historical distribution (2) Log-normal 3-parameter disrtibution is believed as the best fit probability function among Log-normal dist-ributions. (3) In the test of goodness of fit, $x^2-test$ shows that probability of $x^2-valus$ in Log-normal 3-parameter distribution is nearly more than 90%. But in the Simirnov-Kolmogorov test, hypotheses for the probability distributions cannot be rejected at significance level 5% & 1%. (4) Among 7 gauging stations, Dongchon & Koryung-Bridge's records show lower fitness to the theoretical probability functions than other 5 gauging station's

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A Comparison of the Methods for Estimating the Missing Precipitation Values Ungauged (미계측 결측 강수자료 보완 방법의 비교)

  • Yoo, Ju-Hwan;Choi, Yong-Joon;Jung, Kwan-Sue
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1427-1430
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    • 2009
  • The amount and the continuity of the precipitation data used in a hydrological analysis may exert a big influence on the reliability of the analysis. It is a fundamental process to estimate the missing data caused by such as a breakdown of the rainfall recording machine or to expand a short period of rainfall data. In this study the eight methods widely used as methods for estimating are compared. The data used in this research is the annual precipitation amount during 17 years at the Cheolwon station including an ungauged period of 15 years and its five surrounding stations. By use of this certified method the ungauged precipitation values at the Cheolweon station is estimated and the areal average of annual precipitation for 32 years at the Han River basin is calculated.

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Case analysis of the drought events in Geum river basin with climatic water balance. (기후학적 물수지에 의한 금강유역 가뭄사례 분석)

  • Kim, Joo-Cheol;Ahn, Jung-Min;Lee, Sang-Jin;Hwang, Man-Ha
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1452-1456
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    • 2009
  • Water related disasters frequently occur in these days due to global warming and climatic change. This give us that the trend of mal-distribution of available water resources would be increased and the environment of water resources management getting much worse. Therefore the establishment of the effective strategy should be required for water resources management urgently. In this paper the hydrological characteristics and corresponding social phenomena of the drought events in Geum river basin are inspected in depth. The word, social phenomena, means not the quantitative damage but the qualitative social influences and its main characters are analyzed by the collections of the mass media articles. This study will be helpful in prognosticating the future drought occurrence and the establishment of counterplan to them.

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Modeling and Analysis of Soil Moisture Dynamics in the Large River Basin (넓은 유역에 있어서의 토양 수분 동력학의 모델링과 분석)

  • 이재수
    • Proceedings of the Korea Water Resources Association Conference
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    • 1994.02a
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    • pp.449-456
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    • 1994
  • 넓은 지역(Arkansas River Basin)에 대하여 토양 수분을 기본으로한 물 수지 모델이 계절별 년별 시간단위로 연구되었다. 지표면과 대기 수분사이의 상호 작용과 재순환 효과에 대한 연구가 유역의 매개 변수화 과정에서 수행되었으며 대규모의 지표면과 대기사이의 상호 작용에 의하여 넓은 지역의 지표 수문은 장기간의 확률분포함수에 있어서 두가지 즉 건조와 습한 안정상태의 영향을 받는다. 토양수분 균형 방정식에서 추계학적 변동은 주위환경 변동에 의하여 야기되는 안정상태 사이의 변이와 함께 분리된 선호하는 통계학적 안정상태를 초래한다. 과거의 자료를 바탕으로 비선형 물수지 모델이 Arkansas강 유역에 대하여 검정되었다. 모델에서 안정상태 사이의 평균 변이시간이 물리과정의 추계학적 표현과 검정된 모델변수들로부터 계산되었다. 본 연구는 안정상태 사이의 변이시간 혹은 거주시간, 즉 시스템이 주어진 안정상태에 머무는 시간(가뭄이나 홍수상태의 지속기간)의 예측과 밀접한 관계가 있다.

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