• 한국농공학회논문집
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• 제52권4호
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• pp.1-10
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• 2010

In this study, two estimation equations for preparing stream data for distributed storm runoff model were developed by analyzing the nonlinear relation between upstream flow-length and stream width, and between upstream flow-length and stream bed-slope. The equations for stream cell were tested in Chungjudam watershed (6,661 $km^2$) using KIMSTORM. Six storm events occurring between 2003 and 2008 were selected for the model calibration and verification before the test of equations. The average values of the Nash-Sutcliffe model efficiency (ME), the volume conservation index (VCI), the relative error of peak runoff rate (EQp), and the difference of time to peak runoff (DTp) were 0.929, 1.035, 0.037, and -0.406 hr for the calibrated four storm events and 0.956, 0.939, 0.055, and 0.729 hr for the two verified storm events respectively. The estimation equations were tested to the storm events, and compared the flood hydrograph. The test result showed that the estimation equation of stream width reduced the peak runoff and delaying the time to peak runoff, and the estimation equation of stream bed-slope showed the opposite results.

• 한국환경과학회지
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• 제24권4호
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• pp.437-447
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• 2015

Estimation of runoff peak is needed to assess water availability, in order to support the multifaceted water uses and functions, hence to underscore the modalities for efficient water utilization. The magnitude of storm rainfall acts as a primary input for basin level runoff computation. The rainfall-runoff linkage plays a pivotal role in water resource system management and feasibility level planning for resource distribution. Considering this importance, a case study has been carried out in the Hancheon basin of Jeju Island where distinctive hydrological characteristics are investigated for continuous storm rainfall and high permeable geological features. The study aims to estimate unit hydrograph parameters, peak runoff and peak time of storm rainfalls based on Clark unit hydrograph method. For analyzing observed runoff, five storm rainfall events were selected randomly from recent years' rainfall and HEC-hydrologic modeling system (HMS) model was used for rainfall-runoff data processing. The simulation results showed that the peak runoff varies from 164 to 548 m3/sec and peak time (onset) varies from 8 to 27 hours. A comprehensive relationship between Clark unit hydrograph parameters (time of concentration and storage coefficient) has also been derived in this study. The optimized values of the two parameters were verified by the analysis of variance (ANOVA) and runoff comparison performance were analyzed by root mean square error (RMSE) and Nash-Sutcliffe efficiency (NSE) estimation. After statistical analysis of the Clark parameters significance level was found in 5% and runoff performances were found as 3.97 RMSE and 0.99 NSE, respectively. The calibration and validation results indicated strong coherence of unit hydrograph model responses to the actual situation of historical storm runoff events.

• 대한토목학회논문집
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• 제26권1B호
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• pp.15-25
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• 2006

유역형상의 변화에 따라서 이동강우가 유출에 미치는 영향을 운동파이론을 적용하여 분석하였으며, 유역형상은 신장형유역과 정사각형유역 및 장방형유역에 대하여 분석하였고, 이동강우 분포형은 균등분포형, 전진형, 지연형, 중앙집중형을 사용하였다. 이와 같은 형상의 유역에 대하여 다양한 이동속도를 가진 강우가 유역내 하천의 상류방향, 하류방향, 횡방향으로 이동할 때 강우분포형에 따르는 유출수문곡선을 모의하여 그 특성을 비교분석하였다. 유출수문곡선의 모양과 첨두시간, 첨두유량은 시간적, 공간적으로 변화하는 강우와 유역형상에 의하여 크게 영향을 받는다. 횡방향의 이동강우에서는 상류방향과 하류방향의 경우보다 더 큰 첨두유량이 발생하며, 하류방향 이동강우의 첨두유량은 상류방향의 첨두유량보다 더 크게 나타났다. 신장형유역의 경우 하류방향 이동강우의 첨두시간은 상류방향과 횡방향의 경우보다 더 지체되며, 수문곡선의 총유출량과 기저시간은 강우속도가 증가함에 따라 감소하였다.

• 한국농공학회지
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• 제44권3호
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• pp.65-72
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• 2002

Rainfall and runoff data from a forested watershed and irrigated rice paddies at the Bal-an experimental watershed were monitored and analyzed to investigate the variations of runoff characteristics with different land use. The comparisons were conducted fourteen storm events ranging 21.8∼190.2 mm of rainfall. Field data showed that direct runoff from paddies and forested watershed are not significantly different in volume. The peak discharge from forest watershed was less than that from paddies far lighter storms, but became greater fur heavier storms. The peak runoff from the forest watershed was 39 percent greater than from the paddies. The results demonstrate that paddies play an important role to reduce peak discharge from heavy storms as compared to forest.

• 한국환경과학회지
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• 제7권4호
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• pp.451-460
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• 1998

The objectives of this study Is to evaluate the total runoff yield, peak flow and peak flow travel time depending on the urbanization, return period and rainfall patterns at the downstream of Manchon urban watershed in TaeGu City. SWM(Storm Water Management Model) is used for runog analysis based on 5 different steps of urbanization and 4 different types of Hufrs quartile according to 8 return periods. It is analyzed that the order of total runoff yield according to raiun patterns is Huffs 4, Huffs 2. Huffs 3 and Huffs 1 quartile, that of peak flow magnitude is Huffs 2, Huffs 1, Huffs 4 and Huffs 3 quartile at present development ratio. under the 60, 70, 80 and 90ft of urbanization to the 50% of urbanization by means of the rainfall patterns, the mean Increasing ratio of total runoff yield for each case is 4.55, 11.43, 16.07 and 20.02%, that of peak flow is 5.82, 13.61, 17.15 and 18.83%, the mean decreasing ratio of peak flow travel time Is 0.00, 2.44, 5.07 and 6.26%, the mean increasing ratio of runoff depth Is 4.51, 11.42, 16.02 and 20.05% respectively. the mean increasing ratio of total runoff yield by means of each and 19.71%. Therefore, as the result of this study. it can be used for principal data as to storm sewage treatment and flood damage protection planning in urban small watershed.

• 대한토목학회논문집
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• 제31권4B호
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• pp.369-376
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• 2011

마산항, 부산항 등 남동해안의 폭풍해일을 산정하기 위해 3차원 및 2차원 폭풍해일 모델을 구축하여 2003년 태풍 "매미"에 의한 폭풍해일을 수치계산하였다. 태풍 "매미"는 2003년 9월 12일 21시에 중심기압 950 hPa인 상태로 남해안에 상륙하였다. 마산항에서 태풍 "매미"에 의한 peak 시 폭풍해일의 현장관측치는 230 cm, 3차원 모델에 의한 계산결과는 238 cm, 2차원 모델에 의한 계산치는 208 cm이다. 부산항에서 관측된 폭풍해일은 89 cm, 3차원 모델과 2차원 모델에 의한 계산치는 각각 91 cm, 79 cm이다. 본 연구에 의한 3차원 폭풍해일 모델은 현지 폭풍해일을 거의 정확하게 추산하였다. 3차원 모델이 2차원 모델보다 폭풍해일의 peak 시에 현지 폭풍해일을 보다 정확하게 해석하였다. 또한, 2003년 태풍 "매미" 통과시 폭풍류를 수치계산하였다. 마산만 내에서 태풍으로 발생한 표층 유속은 30~60 cm/sec 크기로 만내로 유입하고, 저층에서는 20~40 cm/sec로 마산만에서 외해로 유출하는 흐름패턴을 보여주고 있다.

• 물과 미래
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• 제26권2호
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• pp.49-57
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• 1993

본 연구는 하수관거 설계시, 계획강우의 임계지속기간을 결정하기 위한 것으로서, 지속기간내의 시간적 강우분포형은 Huff의 4분위법에 의하였으며, 20분~240분의 9개의 지속기간을 10년 빈도강우에 대하여 검토하였다. 본 연구에서는 서울시 관내의 18개 유수지 배수구역을 대상으로 해석을 시도하였으며, 유출해석을 위하여 ILLUDAS 모형을 이용하였다. 하수관거의 설계수문량 기준이 되는 첨두유출량을 최대로 발생시키는 계획강우의 임계지속기간은 대체로 30,60분으로 판단되었다. 계획강우의 시간적 분포형별로 임계지속기간을 설정할 수 있도록 첨두유량-유역면적-임계지속기간의 관계도를 제시하였다.

• 한국환경보건학회지
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• 제22권4호
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• pp.33-42
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• 1996

This research is to show the application of runoff model and runoff analysis of urban storm drainage network. the runoff models that were used for this research were RRL, ILLUDAS, and SWMM applicative object basin were Geucknak-chun and Sangmu drainage basin located in Seo-Gu, Kwangju. The runoff analysis employed the design storm that distributed the rainfall intensity according to the return period after the huff's method. The result from the comparative analysis of the three runoff models was as follows The difference of peak runoff by return period was 20-30% at Sangmu drainage area of $3.17 Km^2$, while less than 10% at Geucknak-chun drainage area of $12.7 Km^2$. The peak runoff were similar to all models. At the runoff hydrograph the times between rising and descending points were in the sequence of RRL, ILLUDAS and SWMM, but the peak times were similar to all models. The conveyance coefficient to examine the conveyance of the existing drainage network was 0.94-1.37, which means insecure, in Geucknak-chun drainage basin and 0.69-1.16, which means secure, in sangmu drainage basin.

• 대한토목학회논문집
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• 제42권3호
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• pp.333-342
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• 2022

기후변화의 영향으로 집중호우가 증가하고 있으며, 이로 인한 침수피해가 매년 발생하고 있다. 본 연구는 저영향개발(LID) 시설의 우수 유출저감 효과를 분석하기 위하여, 용두빗물펌프장 유역을 대상으로, 미국 환경보호청(EPA)의 우수유출관리모형(SWMM)을 이용하여, 과거와 미래의 대표 강우사상에 대한 유출분석을 수행하였다. 그 결과 과거 강우사상과 비교하여 미래 대표 강우사상에 대한 침투량은 3.17 % 증가하였지만, 지표면 유출량 및 첨두유량은 각각 32.50 % 및 128.77 % 증가하였다. 이러한 지표면 유출량과 첨두유량의 증가를 감소시키기 위하여 투수성 포장, 옥상녹화 및 빗물정원을 선정하였다. 세 가지 LID 시설의 매개변수와 설치 면적 비율을 조정하여 LID 시설의 적용성을 평가하였다. 그 결과 첨두유량과 지표 유출량을 감소시키고 침투량과 저류량를 증가시키는 투수성 포장, 옥상 정원 그리고 빗물 정원의 적정 매개변수를 찾을 수 있었다. 또한 투수성 포장, 옥상녹화, 빗물정원의 적용 비율이 2:1:3일 때, 첨두유량 26.85 %, 침투량 12.10 %, 지표면 유출량 15.11 %, 저류량 509.47 %의 저감효과가 나타났다. 재현기간별 우수 유출저감 효과를 분석한 결과, 재현기간이 증가할수록 첨두유량과 지표면 유출량의 비중은 늘어나고 침투량과 저류량의 비중은 줄어드는 것으로 나타났다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2021년도 학술발표회
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• pp.153-153
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• 2021

Storm Storm event is one of major issues in South Korea due to devastating damage at its landfall. A series of statistical study on the historical typhoon records consistently insist that the typhoon translation speed (TS) is on slowdown trend annually, and thus provides an urgent topic in assessing the extreme storm surge under future climate change. Even though TS has been regarded as a principal contributor in storm surge dynamics, only a few studies have considered its impact on the storm surge. The landfall angle (LA), another key physical factor of storm surge also needs to be further investigated along with TS. This study aims to elucidate the interaction mechanism among TS, LA, coastal geometry, and storm surge synthetically by performing a series of simulations on the idealized geometries using Delft3D FM. In the simulation, various typhoons are set up according to different combinations of TS and LA, while their trajectories are assumed to be straight with the constant wind speed and the central pressure. Then, typhoons are subjected to make landfall over a set of idealized geometries that have different depth profiles and layouts (i.e., open coasts or bays). The simulation results show that: (i) For the open coasts, the maximum surge height (MSH) increases with increasing TS. (ii) For the constant bed level, a typhoon normal to the coastline resulted in peak MSH due to the lowest effect of the coastal wave. (iii) For the continental shelf with different widths, the slow-moving typhoon will generate the peak MSH around a small LA as the shelf width becomes narrow. (iv) For the bay, MSH enlarges with the ratio of L/E (the length of main-bay axis /gate size) dropping, while the greatest MSH is at L/E=1. These findings suggest that a fast-moving typhoon perpendicular to the coastline over a broad continental shelf will likely generate the extreme storm surge hazard in the future, as well as the slow-moving typhoon will make an acute landfall over a narrow continental shelf.