• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.943-947
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• 2005

This study was intended to interpose an objection about the analysis of rainfall spatial distribution without a proper standard, and offer the improved approach using 1,he geostatistical analysis method to analyze it. For this, spatially distributed daily rainfall data sets were collected for 41 weather stations in study area, and variogram and correlation analysis were conducted. In the results of correlation analysis, it was found that the longer distance between the stations reduces the correlation of the rainfall data, and maltes the characteristics of the rainfall spatial distribution. The variogram analysis shows that correlation range was less than 50 km for the 17 daily rainfall data sets of total 91 sets. It says that it involves some rike, to determine the application method for rainfall spatial distribution without some qualifications, hence the Application standards of the Rainfall Spatial Distribution Analysis Technique, were essential and that was contingent on characteristics of rainfall and landscape.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2010년도 정기 학술발표대회
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• pp.51.2-51.2
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• 2010

A novel approach of Poisson cluster stochastic rainfall generator was validated in its ability to reproduce important rainfall and watershed response characteristics at 104 locations of the United States. The suggested novel approach - The Hybrid Model(THM), as compared to the traditional ones, has an additional function to account for the year-to-year variability of rainfall statistics. The two-sample Kolmogorov-Smirnov test was used to see how well THM and traditional approach of Poisson cluster rainfall model reproduce the distribution of the following hydrologic variables: monthly maximum rainfall depths with 1, 3, 6, 12, and 24 hour duration, monthly maximum flow peaks at the virtual watersheds with Curve Number of 50, 60, 70, 80 and 90; and monthly runoff depths at the same virtual watersheds. In all of the testing variables, THM significantly outperformed the traditional approach. This result indicates that the year-to-year variability of rainfall statistics contains important information about the characteristics of rainfall processes that were not considered by the conventional approach of Poisson cluster rainfall modeling and that further considering it in rainfall simulation will enhance the performance of the rainfall models.

• Environmental Engineering Research
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• 제21권3호
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• pp.226-232
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• 2016

Rainfall is one of crucial factors that impact on our environment. Rainfall data is important in water resources management, flood forecasting, and designing hydraulic structures. However, it is not available in some rural watersheds without rain gauges. Thus, effective ways of interpolating the available records are needed. Despite many widely used spatial interpolation methods, few studies have investigated rainfall center characteristics. Based on the theory that the spatial distribution of convective rainfall event has a definite center with maximum rainfall, we present a mathematical interpolation method to estimate convective rainfall distribution and indicate the rainfall center location and the center rainfall volume. We apply the method to estimate three convective rainfall events in Santa Catalina Island where reliable hydrological data is available. A cross-validation technique is used to evaluate the method. The result shows that the method will suffer from high relative error in two situations: 1) when estimating the minimum rainfall and 2) when estimating an external site. For all other situations, the method's performance is reasonable and acceptable. Since the method is based on a continuous function, it can provide distributed rainfall data for distributed hydrological model sand indicate statistical characteristics of given areas via mathematical calculation.

• 한국물환경학회지
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• 제21권2호
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• pp.184-189
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• 2005

Impacts of non-point source pollution on water quality are well known. In this paper, effects of land use, precipitation characteristics, discharge characteristics on non-point source pollutant loadings at urban, agricultural and forestry watersheds were discussed. Rainfall runoffs from fifteen rainfall events were sampled and analysed at two urban watersheds, one rural watershed, and one forestry watershed. EMCs (Event Mean Concentration) were calculated based on monitored flow rates and concentrations. Statistical analysis carried out with runoff loadings and affecting variables indicated that runoff loadings are weakly correlated with the rainfall intensity and the dry days before rainfall events while showed no correlations with rainfall depth nor runoff quantity. By comparing EMCs between study watersheds on log-normal cumulative probability scale, EMCs ranking were in the descending order of urban watershed>agricultural watershed>forestry watershed for SS, TCOD, TN, and TP.

• 한국농공학회논문집
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• 제53권3호
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• pp.53-58
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• 2011

This study is analyzed the characteristics of the soil erosion with the geotechnical conditions and rainfall conditions, such as the ground slope, the compaction ratio, rainfall intensity and duration of rainfall etc. To this ends, a series of model test are conducted on clayey sands. From the results, the variation of soil loss is analyzed with the geotechnical and the rainfall conditions. The amount of soil loss is decreased as the increase of compaction ratio and is increased as the ground slope, rainfall intensity and the duration of rainfall.

• 한국수자원학회논문집
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• 제42권11호
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• pp.933-951
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• 2009

지구온난화에 따른 기후변화가 우리나라의 물순환 과정에 영향을 미칠 수 있다. 강우는 여러 기상인자들과 복잡한 영향을 주고 받으며 발생한다. 따라서 강우는 물순환 과정에서 기후변화에 따른 영향을 크게 받는 인자 중의 하나이다. 본 연구에서는 강우특성을 나타낼 수 있는 여러 시계열 자료를 구축하였다. 또한 강우의 발생 시계열을 연별, 계절별 및 월별로 구성하여 분석하였다. 분석 방법은 시계열 자료의 평균과 표준편차의 변동성 분석과 경향성 분석을 수행하였다. 또한, 최근 10년 동안에 강우특성의 변화에 대한 상대오차를 계산하여 과거 자료들과 비교하였다. 분석 결과에서 강우자료의 고유 특성인 무작위성에 의하여 뚜렷한 통계적 결과는 나타나지 않았다. 그러나 일반적으로 최근 10년간 강우량은 증가하였으며, 강우일수는 감소하는 추세를 보였다. 또한, 계절별과 월별에 따른 강우특성의 변화가 다르게 나타나고 있음을 확인할 수 있다.

• 한국농공학회논문집
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• 제52권6호
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• pp.75-83
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• 2010

The objective of this paper is to study the discharge characteristics of pollutant loads in small watershed according to probability rainfall using the Hydrologic Simulation Program-Fortran (WinHSPF). The subwatershed of Gosam reservoir watershed in Gyeonggido province was simulated and the probability rainfall of study area was estimated by recurrence interval and duration. The probability rainfalls are 156.5, 205.9 and 277.4 mm for 6 hrs, 12 hrs and 24 hrs in 10 year frequency, and each probability rainfalls is distributed by Huff's 4th quantiles method and applied to HSPF. The pollutant loads were high for initial rainfall. The concentrations of TN, TP and BOD were high as rainfall duration is shorter and rainfall intensity is higher.

• 한국방재학회 논문집
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• 제10권3호
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• pp.147-154
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• 2010

본 연구에서는 강우에 기인하는 산사태에 의한 토사발생특성을 분석하였다. 이를 위해 1차원 불포화 지하수해석을 수행하여 강우에 따른 토양수분의 거동을 추정하였으며, 무한사면해석법을 이용하여 토양수분상태에 따른 유역단위 사면안정해석을 수행하였다. 이 때, 산사태의 발생 및 파괴깊이에 영향을 주는 토양심 및 여러 식생인자들을 고려하였다. 강우사상의 특성에 따른 토사발생특성 분석 결과, 산사태에 의한 토사의 발생에는 강우강도와 강우의 시간적 군집상태가 결정적인 영향을 미친다는 것을 알 수 있었다. 극치강우에 의한 유역 내 토사발생특성 분석결과, 태풍 '루사' 시의 잔여강우량이 다른 극치사상들에 비하여 매우 크게 나타났으며, 이러한 잔여강우량이 발생된 토사의 운송에 기여하였을 것으로 파악되었다. 아울러, 소수의 극치강우에 의하여 발생한 토사량이 유역 내 전체 토사발생량의 많은 부분을 차지함을 알 수 있었다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.132-134
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• 1999

Rainfall characteristics for designing the optimum millimeter-wave communication systems from two rainfall data set was analyzed. Two rainfall data sets were compared; one-minute rainfall rate data, one-hour synoptic observation data. Each data set has different observation method, sampling frequency. We looked for tendency and quality confluence between two data sets. We showed several results using one-minute rainfall data by millimeter-wave attenuation model. A climatological one-minute rainfall rate data set over Korean Peninsula will be made after data quality control procedure

• 한국습지학회지
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• 제4권2호
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• pp.43-56
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• 2002

About 12 rain gauge stations of Korea, annual maximum rainfall series of before and after 1980 whose durations are 1, 2, 3, 6, 12, 24, 48, 72 hours respectively were composed and statistical characteristics of those time series were calculated and probability rainfall were estimated by L-moment frequency analysis method and compared each other in order to investigate the recent quantitative rainfall variations. And also, distribution curves of each statistical variations for each duration were constructed by using Kigging method to look into spacial rainfall variation aspects. As a result, We could confirm recent rainfall increase in the South Korea. And spatial increase pattern of standard deviation and frequency rainfall appeared analogously each other. 1n the cases of comparatively short rainfall duration, we could see relatively low increase or decrease tendency in Chungchong Province, Cholla-bukdo, Cholla-namdo eastern part, Kyongsang-namdo western part area. While, variations happened great1y in seaside district of east coast, southwest seashore, Inchon area etc. In the cases of longer durations relatively low increase was showed in southern seashore such as Yeosoo area and as distance recedes from this area, showed gradually augmented tendency. The aspect of mean looks similar tendency of above except that the variation rate of almost seaside district are big in the case of shorter durations. In addition, rainfall increases of short durations which became the center of hydrologist and meteorologist are unconfirmed in this study.