• 물과 미래
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• 제29권4호
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• pp.139-147
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• 1996

유역의 하천형태학적 특성은 그 유역의 수문 및 수리학적특성과 밀접한 관계를 가지고 있다. 본연구는 우리나라 중부지방의 중소하천에 대한 계획하폭을 산정하는 공식을 제시하는데 목적이 있다. 계획홍수량과 유역면적 및 하천연장의 자료로서 하폭을 얻는데 다음과 같은 결론을 얻었다. : (1) 계획홍수량(Q)과 하폭(B)의 관계로 나타낸 하폭식은 $B=1.532A^{0.644.}$; (2) 유역면적(A)과 하폭(B)과의 관계로 나타낸 하폭식은 $B=12.392A^{0.511}$; (3) 하천연장(L)과 하폭(B)과의 관계로 나타낸 하폭식은 $B=10.509l^{0.852}$.

• 한국콘텐츠학회논문지
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• 제13권5호
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• pp.485-492
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• 2013

낙동강에 위치한 하회마을의 점사주는 상류의 댐에 의해 수량이 조절됨에 따라 토사수리학적 특성이 상당히 변화되었으며, 식생이 발생하는 등 옛 모습을 상실해 가고 있다. 이 연구는 낙동강의 중상류에 위치한 하회지구에 평면 이차원 하상변동 및 수질예측 수치모형인 KU-RLMS 모형을 적용하여 하회마을 앞의 점사주에 영향을 미치는 수리학적 특성 변화를 규명할 목적으로 수행하였다. 평면 이차원 수치모형을 이용한 흐름모의 조건은 고정상 수리모형실험의 실험조건에 대하여 수행하였다. 수치모의 결과 하회마을을 지나면서 부용대 앞의 좌안측에서 흐름이 가속되는 현상이 나타났고, 하회마을 직하류의 우안측에서는 순환이 발생하는 것으로 예측되었다. 이는 수리모형실험 결과와도 일치하는 경향이다. 계획홍수량 흐름조건의 경우 순환현상이 발생하는 하회마을 직하류의 우안측은 유속이 빠른 좌안측보다 약 1.0 m 이상 수위가 상승하는 것으로 예측되었으며, 수리모형실험 결과와도 일치함을 확인할 수 있었다.

• 한국농공학회지
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• 제27권4호
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• pp.42-52
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• 1985

This study was attempted to derivate empirical formulas for the runoff: ratio during ilood. season at three watersheds of Dan Yang, Chung Ju, and Yeo Ju are located at upper, middle, and lower portion of Nam Han river basin, respectively. Obtained formulas for flood runoff ratio can be applied as an element for the estimation, peak discharge for the design of various hydraulics structures which can be concidented with meteorological and topographical condition. The obtained through this study were analyzed as follows. 1.It was found that the magnitude of runoff ratio depends on the amount of rainfall for all studying basins. 2.Empirical formulas 'for the runoff' ratio were derivated as 1- 2,707 Rt0.345, 1-1.691 Rt0.242 and 1-1.807 Rt0.227 at Dan Yang, Chung Ju and Yeo Ju watershed, respectively. 3.The magnitude of runoff ratio was appeared in the order of Dan Yang, Chung Ju, and Yeo Ju are located at upper, middle and lower portion of Nam Han rivet basin, respectively. 4.It was assumed that in general the more it rains, the lesser becomes the ratio of loss rainfall. Especially, the ratio of loss rainfall for Dan Yang, upper portion of river basin was shown as the lowest among three watersheds. Besides, the magnitude of that was appeared in the order of Chung Ju and Yeo Ju watershed located at middle, and lower part of river basin, respectively. 5.Relative and standard errors of runoff ratio calculated by empirical formulas were shown to be within ten percent to the observed runoff ratio in all watersheds. 6.It is urgently essential that the effect of antecedent rainfall have an influence on the next coming flood should be studied in near future.

• 농촌계획
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• 제21권4호
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• pp.177-186
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• 2015

The main objective of this study was to assess the applicability of IoT (Internet of Things)-based flood management under climate change by developing intelligent water level monitoring platform based on IoT. In this study, Arduino Uno was selected as the development board, which is an open-source electronic platform. Arduino Uno was designed to connect the ultrasonic sensor, temperature sensor, and data logger shield for implementing IoT. Arduino IDE (Integrated Development Environment) was selected as the Arduino software and used to develop the intelligent algorithm to measure and calibrate the real-time water level automatically. The intelligent water level monitoring platform consists of water level measurement, temperature calibration, data calibration, stage-discharge relationship, and data logger algorithms. Water level measurement and temperature calibration algorithm corrected the bias inherent in the ultrasonic sensor. Data calibration algorithm analyzed and corrected the outliers during the measurement process. The verification of the intelligent water level measurement algorithm was performed by comparing water levels using the tape and ultrasonic sensor, which was generated by measuring water levels at regular intervals up to the maximum level. The statistics of the slope of the regression line and $R^2$ were 1.00 and 0.99, respectively which were considered acceptable. The error was 0.0575 cm. The verification of data calibration algorithm was performed by analyzing water levels containing all error codes in a time series graph. The intelligent platform developed in this study may contribute to the public IoT service, which is applicable to intelligent flood management under climate change.

• 한국수자원학회논문집
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• 제41권12호
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• pp.1211-1218
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• 2008

본 연구의 목적은 다목적 유전자 알고리즘을 이용하여 우수유출 저류지를 소유역에 분담하여 설치 계획하는데있다. 이를 위해 우수유출 저류지의 위치 및 규모를 최적화하기 위한 모형을 개발하였다. 이 모형은 크게 2가지로 나뉘어 지는데, 유역유출모형과 최적해를 구하기 위하여 도입한 다목적 유전자 알고리즘(MOGAs)이다. 이러한 최적화 모형을 모의하기 위하여 목적함수는 첨두유출량과 저류지 저류용량의 함수로 설정하고, 제한조건은 기본적으로 구조적 제한과 저류용량 및 운영목적에 따라 설정하였다. 본 연구를 위해 만들어진 최적화 모형은 안양시 관양유역에 실제 적용해 보았으며, 그 결과 주어진 제약조건내에서 상류지역에 저류지가 설치되는 경우가 최적값으로 나타난 것을 통해 적절하게 잘 모의된 것으로 보인다. 그밖에 On-line 및 Off-line 저류지가 동시에 건설되는 경우에도 함께 최적화 모의가 가능한지도 살펴보았다. 본 연구를 통해 제시한 방법론은 향후 도시유역내의 홍수피해 저감계획시 활용될 수 있을 것이다.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.54-55
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• 2015

Increase of impervious areas due to expansion of housing area, commercial and business building of urban is resulting in property change of stormwater runoff. Also, rapid urbanization and heavy rain due to climate change lead to urban flood and debris flow damage. In 2010 and 2011, Seoul had experienced shocking flooding damages by heavy rain. All these have led to increased interest in applying LID and decentralized rainwater management as a means of urban hydrologic cycle restoration and Natural Disaster Prevention such as flooding and so on. Urban development is a cause of expansion of impervious area. It reduces infiltration of rain water and may increase runoff volume from storms. Low Impact Development (LID) methods is to mimic the predevelopment site hydrology by using site design techniques that store, infiltrate, evaporate, detain runoff, and reduction flooding. Use of these techniques helps to reduce off-site runoff and ensure adequate groundwater recharge. The contents of this paper include a hydrologic analysis on a site and an evaluation of flooding reduction effect of LID practice facilities planned on the site. The region of this Case study is LID Rainwater Management Demonstration District in A-new town and P-new town, Korea. LID Practice facilities were designed on the area of rainwater management demonstration district in new town. We performed analysis of reduction effect about flood discharge. SWMM5 has been developed as a model to analyze the hydrologic impacts of LID facilities. For this study, we used weather data for around 38 years from January 1973 to August 2014 collected from the new town City Observatory near the district. Using the weather data, we performed continuous simulation of urban runoff in order to analyze impacts on the Stream from the development of the district and the installation of LID facilities. This is a new approach to stormwater management system which is different from existing end-of-pipe type management system. We suggest that LID should be discussed as a efficient method of urban disasters and climate change control in future land use, sewer and stormwater management planning.

• 한국수자원학회논문집
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• 제43권3호
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• pp.275-282
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• 2010

암거의 규격 설계는 상류부의 수위를 과다하게 상승시키지 않는 상태에서 안전하게 계획홍수량을 하류로 소통시킬 수 있도록 최적의 단면을 결정하는 것이다. 현재 국내 암거 설계는 한국도로공사(1991)에서 발표한 "도로배수계획"을 이용하고 있는데, 이는 주로 미국도로성(FHWA)에서 발표한 설계기법을 따른 것이다. 이 기법은 계산 도표를 이용하여 설계하는 방법으로 주관적인 오차가 생길 수 있으며 전산해석에 있어서도 큰 장애요인이 될 수 있다. 본 연구에서는 기존 연구에서 기술된 암거 설계법을 전반적으로 재검토하여 일부 수식 전개 과정에서 발생한 오류를 수정하고, 암거의 규격 산정 시 암거의 형상을 미리 결정하여 암거 프로그램 개발 시 효율적일 것으로 판단되는 새로운 방법을 개발하였다. 특히 원형 암거의 수리해석 시 한계수심과 한계조건 속도수두의 해를 미국도로성에서는 계산도표를 이용하여 구하는 기법을 제시한 반면에 본 연구에서는 양해적 산정식으로 구하는 기법을 개발하였다.

• 한국수자원학회논문집
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• 제34권5호
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• pp.415-426
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• 2001

재해영향평가제도가 시행된 이후 평가서에는 홍수량 산정 및 개발로 인해 증가된 유출량에 대한 대처방안으로 저류지용량을 산정할 때 임계지속기간의 개념을 도입하여 각종 수문량이 산정된다. 임계지속기간은 수공구조물의 종류, 유역특성과 계획강우의 시간적분포 및 재현기가, 유출모형에 따라 변화한다. 본 연구에서는 저류지 설계시 소요용량을 결정하기 위해 기존 연구에서 제안한 바 있는 저류비의 개념을 이용하여 산정된 저류지용량과 강우지속기간에 따른 저류지용적이 최대가 되는 때의 저류지용적 등을 비교·분석함으로써 저류지 설계시 적정용량을 산정하는 방법을 제안하였다. 추후 유출수문곡선으로부터 최대부하를 야기시키는 계획강우의 임계지속기간을 정하는 문제는 다양한 유출모형과 실적자료를 통한 강우-유출해석과 연계시켜야 할 것으로 판단된다.

• 한국안전학회지
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• 제33권4호
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• pp.119-126
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• 2018

In recent years, as flood damage caused by heavy rains increased, the great-depth tunnel using urban underground space is emerging as a countermeasure of urban inundation. The great-depth tunnel is used to reduce urban inundation by using the underground space. The drainage efficiency of great-depth tunnel depends on the intake design, which leads to increase discharge into the underground space. The spiral intake and the tangential intake are commonly used for the inlet facility. The spiral intake creates a vortex flow along the drop shaft and reduces an energy of the flow by the wall friction. In the tangential intake, flow simply falls down into the drop shaft, and the design is simple to construct compared to the spiral intake. In the case of the spiral intake, the water level at the drop shaft entrance is risen due to the chocking induced by the flowrate increase. The drainage efficiency of the tangential intake decreases because the flow is not sufficiently accelerated under low flow conditions. Therefore, to compensate disadvantages of the previously suggested intake design, the multi-stage intake was developed which can stably withdraw water even under a low flow rate below the design flow rate. The hydraulic characteristics in the multi-stage intake were analyzed by changing the flow rate to compare the drainage performance according to the intake design. From the measurements, the drainage efficiency was improved in both the low and high flow rate conditions when the multi-stage inlet was employed.

• 한국농공학회지
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• 제37권3_4호
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• pp.34-47
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• 1995

It is experienced fact as a regular annual event that the structure to he designed on unreasonable flood for the agricultural structures including reservoirs have been brought not only loss of lives, but also enormous property damage. For the solution of this problem at issue, this study was conducted to develop an optimal runoff hydrograph model by comparison of the peak flows and time to peak between observed and simulated flows derived by linear time-invariant and linear time-variant models under the condition of having a short duration of heavy rainfall with uniform rainfall intensity at nine small watersheds which are within the range of 55.9 to 140.7 square kilometers in area in Han, Geum, Nagdong and Yeongsan Rivers. The results obtained through this study can be summarized as follows. 1. Storage constants and Gamma function arguments were calculated within the range of 1.2 to 6.42 and of 1.28 to 8.05 respectively by the moment method as the parameters for the analysis of runoff hydrograph based on linear time-invariant model. 2. Parameters for both linear time-invariant and linear time-variant models were calibrated with nine gaged watershed data, using a trial and error method. The resulting parameters including Gamma function argument, N and storage constant, K for linear time-invariant model were related statistically to watershed characteristic variables such as area, slope, length of main stream and the centroid length of the basin. 3. Average relative errors of the simulated peak discharge of calibrated runoff hydrographs by using linear time-variant and linear time-invariant models were shown to be 0.75 and 5.42 percent respectively to the peak of observed runoff hydrographs. Correlation coefficients for the statistical analysis in the same condition were shown to be 0.999 and 0.978 with a high significance respectively. Therefore, it can be concluded that the accuracy of a linear time-variant model is approaching more closely to the observed runoff hydrograph than that of a linear time-invariant model in the applied watersheds. 4. Average relative errors of the time to peak of calibrated runoff hydrographs by using linear time-variant and linear time-invariant models were shown to be 16.44 and 19.89 percent respectively to the time to peak of observed runoff hydrographs. Correlation coefficients in the same condition were also shown to be 0.999 and 0.886 with a high significance respectively. 5. It can be seen that the shape of simulated hydrograph based on a linear time- variant model is getting closer to the observed runoff hydrograph than that of a linear time-invariant model in the applied watersheds. 6. Two different models were verified with different rainfall-runoff events from data for the calibration by relative error and correlation analysis. Consequently, it can be generally concluded that verification results for the peak discharge and time to peak of simulated runoff hydrographs were in good agreement with those of calibrated runoff hydrographs.