Gamma 및 비Gamma군 분포모형에 의한 강우의 지점 및 지역빈도 비교분석 (I)

류경식,이순혁,Ryoo, Kyong-Sik,Lee, Soon-Hyuk 한국농공학회 2004 한국농공학회논문집 Vol.46 No.4

This study was conducted to derive the design rainfall by the consecutive duration using the at-site frequency analysis. Using the errors, K-S tests and LH-moment ratios, Log Pearson type 3 (LP3) and Generalized Extreme Value (GEV) distributions of Gamma and Non-Gamma Family, respectively were identified as the optimal probability distributions among applied distributions. Parameters of GEV and LP3 distributions were estimated by the method of L and LH-moments and the Indirect method of moments respectively. Design rainfalls following the consecutive duration were derived by at-site frequency analysis using the observed and simulated data resulted from Monte Carlo techniques. Relative root-mean-square error (RRMSE) and relative efficiency (RE) in RRMSE for the design rainfall derived by at-site analysis in the observed and simulated data were computed and compared. It has shown that at-site frequency analysis by GEV distribution using L-moments is confirmed as more reliable than that of GEV and LP3 distributions using LH-moments and Indirect method of moments in view of relative efficiency.

위험도를 고려한 설계홍수량 유도

류경식 ( Ryoo Kyong-sik ),이순혁 ( Lee Soon-hyuk ),맹승진 ( Maeng Sung-jin ) 한국농공학회 2004 한국농공학회 학술대회초록집 Vol.2004 No.-

모든 수공구조물은 재현기간에 따른 설계홍수량에 맞춰 설계하지만 이는 설계재현기간동안 예상된 설계홍수량보다 큰 홍수량이 발생할 수 있는 위험을 항상 내포하고 있다. 이와같은 위험성을 제거하기 위하여 설계재현기간에 따른 예상설계홍수량을 초과할 위험을 수치화하여 각 위험도에 맞는 설계홍수량을 제시하는 것이 무엇보다도 중요하다. 이에 본 연구에서는 우리나라 대표수계인 한강, 낙동강, 영산강, 섬진강의 7개 유역에 대한 연최대 홍수량을 사용하여 이들 자료에 대한 신뢰도를 판정하고, K-S test에 의해 GEV분포모형과 Gamma분포모형의 적합도를 검정한 후 L-모멘트법에 의해 각 분포형의 매개변수를 구하였고, L-모멘트법에 따른 설계흥수량을 유도하였다. 또한, 유도된 설계홍수량과 플로팅포지션법을 달리하여 비교분석한 후, 적정한 것으로 판단된 GEV분포모형에 대한 설계홍수량의 위험도 수준별 및 빈도별 홍수량을 유도하였다. 또한, 위험도를 고려치 않은 현존 빈도별 설계홍수량은 수공구조물의 안정성에 심대한 영향을 미칠 수 있으므로 수준별 위험도를 고려한 설계홍수량의 유도와 함께 위험도의 수준을 사회경제적인 측면을 고려하여 이에 맞게 설계홍수량을 결정함이 바람직할 것으로 고찰되었다. The purpose of this study is to derive design floods by the risk levels. Seven watersheds were selected for the application from Han, Nagdong, Yeongsan and Seomjin rivers. The tests for Independence, Homogeneity and detection of outliers were used Wald-Wolfowitz’s test, Mann-Whitney's test and Grubbs and Beck test respectively. The test of goodness of fit for the applied probability distribution was performed by Kolmogorov-Smirnov test. Comparative analysis of design floods was carried out between GEV and Gamma distributions. Consequently, Design floods were derived by the risk levels using GEV distribution.

홍수기 저수지 유입량 예측을 위한 다중회귀모형 개발

류경식(Ryoo Kyong-Sik),정구열(Chong Koo-Yol) 대한토목학회 2008 대한토목학회 학술대회 Vol.2008 No.10

RRFS 모형을 이용한 대청댐유역 유출성분분석

류경식 ( Kyong Sik Ryoo ),황만하 ( Man Ha Hwang ),이상진 ( Sang Jin Lee ),정우창 ( Woo Chang Jeong ),이배성 ( Bae Sung Lee ) 한국농공학회 2006 한국농공학회 학술대회초록집 Vol.2006 No.-

This study is for analysis of both the runoff attribute and the water accounting related in the water management. RRFS modelling with runoff attribute analysis was used to calculate naturalized streamflow at each sub-basin of the Daecheong Dam basin. Analysis of both the runoff attribute and the WAI(Water Accounting Index) was performed by monthly, yearly and basin in the Daecheong dam basin. Results show that base flow from direct flow concentrated in two month(July to August) is influenced in four month(July to October) and water use is unstable while the initial agricultural water(May) is supplied.

기왕 홍수자료를 통한 다목적댐 홍수빈도분석

류경식 ( Kyong Sik Ryoo ),이순혁 ( Soon Hyuk Lee ),황만하 ( Man Ha Hwang ),고익환 ( Ick Hwan Ko ) 한국농공학회 2006 한국농공학회 학술대회초록집 Vol.2006 No.-

This study is to derive the design floods by optimal distribution using the L-moment method. Parameters for the applied distributions were estimated by the L-moment for the annual flood flows of the each watersheds. Design floods obtained by the applied distributions were compared by the relative mean errors, relative absolute errors and root mean square errors. Results show that the optimal distributions for the each watersheds are that Soyang and Andong watersheds are Log-pearson type 3; Chungju watershed is Generalized Logistic; Namgang watershed is Generalized Pareto; Daecheong watershed is Gumbel; and Seomjin is Generalized Extreme Value.

Log-Pearson Type III 및 GEV분포모형에 의한 강우의 지점 및 지역빈도 비교분석

류경식 ( Ryoo Kyong Sik ),이순혁 ( Lee Soon Hyunk ) 한국농공학회 2003 한국농공학회 학술대회초록집 Vol.2003 No.-

This study was conducted to draw design rainfall for the regional design rainfall derived by the optimal distribution and method of frequency analysis. The design rainfalls were calculated by the regional and at-site analysis for Log-Pearson type III and GEV distributions and were compared with Relative efficiency(RE) which is ratio of Relative root-mean-square error (RRMSE) by the regional and at-site analysis for Log-Pearson type III and GEV distributions. Consequently, optimal design rainfalls following the regions and consecutive durations were derived by the regional frequency analysis for GEV distribution and design rainfall maps were drawn by GIS techniques.

물관리 운영차원에서 산정된 금강유역 용수이용현황

류경식 ( Ryoo Kyong Sik ),황만하 ( Hwang Man Ha ),이상진 ( Lee Sang Jin ) 한국농공학회 2007 한국농공학회 학술대회초록집 Vol.2007 No.-

In general method to estimate the water supplies in the large-scale basin, indirect estimation method such as unit loading factor method has been used. However, the estimated water supplies are much different to the real water supplies used in the any basin because these general methods estimate them considering water supply demands only. Especially, water supplies for irrigation are big different to the real water supplies in which the water supplies for irrigation are depend on the weather conditions such as evaporation, basin conditions such as infiltration, the reservoir operation rule for irrigation water, and distribution methods. Thus, a new estimation method is developed to estimate the real water demands which is essential factors for the effective water resources operation in the basin. This method is for estimating the water supplies and return rates based on the survey of the irrigation reservoirs and the analysis of effects to the stream flows, return flows, and water supplies for irrigation which water supplies and return rates are used in the basin water management model. The water supply usages in each subbasin are validated by comparisons between the simulated discharges from the basin water management model and the discharges measured in the control points.

대규모 유역에서의 적정 용수이용량 산정

류경식 ( Ryoo Kyong-sik ),황만하 ( Hwang Man-ha ) 한국농공학회 2007 한국농공학회논문집 Vol.49 No.3

In general method to estimate the water supplies in the large-scale basin, indirect estimation method such as unit loading factor method has been used. However, the estimated water supplies are much different to the real water supplies used in the any basin because these general methods estimate them considering water supply demands only. Especially, water supplies for irrigation are big different to the real water supplies in which the water supplies for irrigation are depend on the weather conditions such as evaporation, basin conditions such as infiltration, the reservoir operation rule for irrigation water, and distribution methods. Thus, a new estimation method is developed to estimate the real water demands which is essential factors for the effective water resources operation in the basin. This method is for estimating the water supplies and return rates based on the survey of the irrigation reservoirs and the analysis of effects to the stream flows, return flows, and water supplies for irrigation which water supplies and return rates are used in the basin water management model. The water supply usages in each subbasin are validated by comparisons between the simulated discharges from the basin water management model and the discharges measured in the control points.

호우사상에 따른 댐 유역 수문사상 변화 분석

류경식(Ryoo, Kyong-Sik),추태호(Choo, Tai-Ho) 한국산학기술학회 2008 한국산학기술학회 학술대회 Vol.- No.-

최근 지구 온난화에 따른 이상기후 변화로 인해 게릴라성 집중호우와 같은 다양한 강우패턴이 발생되고 있으며 홍수기 저수지 유입량은 비록 동일 양의 강우가 발생한 경우라도 선행강우량, 무강우일 수, 호우발생전 초기유입량 등과 같은 수문사상들로 인해 많은 차이가 발생되고 있는 실정이다. 따라 서 본 연구에서는 신속함이 요하는 홍수기 저수지 운영시 신속한 의사결정을 돕기 위해 과거 홍수기 댐 유입율과 유역 수문사상과의 관계를 분석하고자 한다. 이를 위해 한강수계내 다목적 댐인 소양강, 충주 및 횡성댐의 과거 호우사상을 대상으로 유역내 각종 수문사상들을 독립변수로 한 회귀분석을 실시하여 홍수 이벤트 발생전 유역상황을 토대로 예상되는 강우에 따른 예상 유출율을 산정한다. 과거 호우사상에 대한 유출율 산정은 직접유출과 기저유출을 분리한 후 직접유출이 종료되는 시점까지의 유출량과 강우량의 비로서 산정하였으며 직접유출과 기저유출 분리방법은 주파수 분리방법을 이용하고자 한다.

관측년수변화를 고려한 설계강우량 산정

류경식 ( Ryoo Kyong-sik ),이순혁 ( Lee Soon-hyuk ),황만하 ( Hwang Man-ha ),이상진 ( Lee Sang-jin ) 한국농공학회 2005 한국농공학회 학술대회초록집 Vol.2005 No.-

The objective of this study is to check into variation trends of design rainfall according to change of the number of years for observed data. To make comparative study of the relation between design rainfall and recorded year, this study was used maximum rainfall for 24-hr consecutive duration at Gangneung, Seoul, Incheon, Chupungnyeong, Pohang, Daegu, Jeonju, Ulsan, Gwangju, Busan, Mokpo and Yeosu rainfall stations. The tests for Independence, Homogeneity and detection of outliers were used Wald-Wolfowitz's test, Mann-Whitney's test and Grubbs and Beck test respectively. To select appopriate distribution, the distribution of genaralized pareto(GPA), generalized extreme value(GEV), generalized logistic(GLO), lognormal and pearson type 3 distribution is judged by L-moment ratio diagram and Kolmogorov-Smirnov (K-S) test. Design rainfall was estimated by at-site frequency analysis using L-moments and Generalized extreme value(GEV) distribution according to change of the number of years for observed data. Through the comparative analysis for design rainfall induced by L-moments and GEV distribution, relationship between design rainfall and recorded year is provided.