• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.679-682
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• 2008

Probability precipitation is one of the most important factor for designing the hydrology structures. Probability precipitation is calculated based on the frequency analysis on each durations of annual maximum rainfall data. For frequency analysis we need a conversion factor between the rain data per random-time interval and fixed-time-interval. In this study, the minutely precipitation data on observatory of the Meteorological Administration are used for 37 stations. Therefore, we should conversion factors between the rain data per minute and fixed-time-interval.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(2)
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• pp.1245-1246
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• 2005

• 대한토목학회논문집
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• 제29권2B호
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• pp.141-153
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• 2009

우리나라에서 발생하는 호우의 발생원인은 태풍과 집중호우로 구분할 수 있다. 태풍은 비정기적으로 우리나라에 영향을 끼치며 막대한 강우를 유발시키며, 집중호우는 전선형 호우와 같은 장마와 지형성 호우인 국지성 호우를 의미한다. 태풍과 집중호우는 매년 우리나라에 극한강우를 발생시킴으로써 침수 등의 재해를 유발시키고 있다. 따라서 본 연구에서는 호우의 원인을 태풍과 집중호우로 구분하여, 집중호우로 인한 강우자료를 이용하여 확률강우량을 산정하였다. 집중호우에 대한 평가는 돌발홍수와 같은 짧은 지속시간의 호우에 대한 분석에 활용할 수 있다. 확률강우량의 산정방법은 일반적인 매개변수적 지점빈도해석과 EST를 적용하였다. EST의 적용을 위하여 해수면온도 및 습윤지수와 같은 수문기상인자와 집중호우로 인한 연최대시간강수량과의 상관성 분석을 수행하였다. 상관성 분석 결과에서 우리나라의 집중호우로 인한 강우량은 해수면온도와 밀접한 관련이 있는 것으로 나타났다. 또한, EST에 의해 산정된 확률강우량은 빈도해석한 확률강우량에 비하여 경기도 등의 우리나라의 서중부 지역에서 보다 큰 결과를 나타내었다. 따라서 우리나라의 서중부 지역에서는 집중호우로 인한 극한강우 발생에 대비해야 할 필요성이 있다.

• 한국수자원학회논문집
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• 제50권12호
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• pp.889-896
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• 2017

본 연구에서는 무심천 유역을 대상으로 지표수-지하수 통합해석 모형인 SWAT-MODFLOW를 이용하여 수량이 부족한 하천으로 지하수를 이용한 물공급 방안을 모색하였다. 2011년부터 2015년까지 다양한 모의실험을 수행한 결과 극한가뭄이 도래했던 2015년에 지하수 공급에 의한 월 유출량의 변화는 현 양수시 23%, 최대 양수시에는 68.3%의 증가를 나타냈다. 이를 연간 지하수 함양량으로 산정할 경우 현 이용량을 적용하면 연평균 강수량의 6.2%인 75 mm, 최대 이용량 적용시 연평균 강수량의 24%인 290 mm에 해당하여 연간 안정적인 공급이 가능한 것으로 나타났다. 본 연구는 가뭄에 취약한 지표수자원과 달리 지하수는 하천수 부족시 물공급의 효과적인 대안이 될 수 있을 것으로 판단된다.

• 한국농공학회지
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• 제43권4호
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• pp.57-68
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• 2001

It is matter of common knowledge to give impetus to the water resources development to cope with increasing demand and supply for the water utilization project including agricultural living and industrial water owing to the economic and civilization development in recent years. Regional design rainfall is necessary or the design of the dam reservoir levee and drainage facilities for the development of various kinds of essential waters including agricultural water. For the estimation of the regional design rainfall classification of the climatologically an geographically homogeneous regions should be preceded preferentially This study was mainly conducted to derive the optimal regionalization of the precipitation data which can be classified by the climatologically and geographically homogeneous regions all over the regions except Cheju and Wulreung islands in Korea. A total of 65 rain gauges were used to regional analysis of precipitation. Annual maximum series for the consecutive durations of 1, 3, 6, 12, 24, 36, 48 and 72hr were used for various statistical analysis. Both K-means clustering and mean annual precipitation methods are used to identify homogeneous regions all over the regions. Nine and five homogeneous regions for the precipitation were classified by the K-means clustering and mean annual methods, respectively. Finally, Five homogeneous regions were established by the trial and error method with homogeneity test using statistics of $\chi$$^2$ distribution.

• 대기
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• 제32권1호
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• pp.1-15
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• 2022

Recently, Japan's Meteorological Research Institute presented the d4PDF database (Database for Policy Decision-Making for Future Climate Change, d4PDF) through large-scale climate ensemble simulations to overcome uncertainty arising from variability when the general circulation model represents extreme-scale precipitation. In this study, the change of precipitation characteristics between the historical and future climate conditions in the Yongdam-dam basin was analyzed using the d4PDF data. The result shows that annual mean precipitation and seasonal mean precipitation increased by more than 10% in future climate conditions. This study also performed an analysis on the change of the return period rainfall. The annual maximum daily rainfall was extracted for each climatic condition, and the rainfall with each return period was estimated. In this process, we represent the extreme-scale rainfall corresponding to a very long return period without any statistical model and method as the d4PDF provides rainfall data during 3,000 years for historical climate conditions and during 5,400 years for future climate conditions. The rainfall with a 50-year return period under future climate conditions exceeded the rainfall with a 100-year return period under historical climate conditions. Consequently, in future climate conditions, the magnitude of rainfall increased at the same return period and, the return period decreased at the same magnitude of rainfall. In this study, by using the d4PDF data, it was possible to analyze the change in extreme magnitude of rainfall.

• Water Engineering Research
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• 제2권1호
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• pp.1-10
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• 2001

The frequency analyses for the precipitation data in Korea were performed. We used daily maximum series, monthly maximum series, and annual series. For nonparametric frequency analyses, variable kernel estimators were used. Nonparametric methods do not require assumptions about the underlying populations from which the data are obtained. Therefore, they are better suited for multimodal distributions with the advantage of not requiring a distributional assumption. In order to compare their performance with parametric distributions, we considered several probability density functions. They are Gamma, Gumbel, Log-normal, Log-Pearson type III, Exponential, Generalized logistic, Generalized Pareto, and Wakeby distributions. The variable kernel estimates are comparable and are in the middle of the range of the parametric estimates. The variable kernel estimates show a very small probability in extrapolation beyond the largest observed data in the sample. However, the log-variable kernel estimates remedied these defects with the log-transformed data.

• 농촌계획
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• 제21권2호
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• pp.127-135
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• 2015

In recent years, meteorological disasters have frequently occurred in rural areas. As a result, there have been growing concerns over the protective measures needed. In order to avoid natural risks and damage, and to strengthen countermeasure to meteorological disasters, local governments needs to be prepared. Therefore, this paper seeks to prevent meteorological disasters through mapping of inundation vulnerability in agricultural land, Chungcheongnam-do. In doing so, this study were considered 5 variables (i.e. precipitation, region of altitude below 50m, region of slope gradient is below 10 degree, distance from river within less 50m) for creating vulnerability map. The precipitation was excluded in five variables. Since, the precipitation which include Daily maximum precipitation, 2-Daily maximum precipitation, summer precipitation was not any correlation among them. The results of analysing four variables, exclusive of precipitation, were showed that the agricultural lands where located in Dangjin, Buyeo, Hongseong and Asan were low correlation of inundation vulnerability by overlapping analysis. Moreover, The correlation analysis was showed low correlation between each factors and the annual average area of agricultural lands' inundation, whereas, the correlation analysis which was overlapping each factor showed high correlation. In conclusion, in order to create reliable vulnerability map in agricultural lands, Chungcheongnam-do, it must be considered to overlap analysis of the four main factors such region of altitude below 50m, region of slope gradient is below 10 degree, distance from river within less 50m. We suppose that this study's analysis can help to set the preparedness site of agricultural lands inundation.

• 한국방재학회 논문집
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• 제11권2호
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• pp.113-125
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• 2011

본 연구에서는 1973년부터 2009년까지 전국 기상관측소 59개 지점에 대한 연강수량, 지속시간별 연최대강수량, 그리고 한계치별(threshold) 강수일수 등 극한지수를 이용하여 지역특성에 따른 추세특성을 분석하였다. 그리고 59개 지점에 대한 위치적 특성을 구분하기 위하여 고도, 위도, 경도, 유역, 내륙 및 해안(동해, 서해, 남해), 도시화 및 비도시화 등으로 분류하여 지역특성에 따른 추세분석을 실시하였다. 강수량 자료에 대한 추세분석 결과, 강수일수를 제외한 대부분의 변수들은 증가하는 경향성이 나타났다. 지역특성별 증가특성의 경우 고도가 높아질수록 증가추세가 뚜렷하였고, 유역별로는 한강유역의 증가추세가 가장 크고 영산강유역의 증가추세가 가장 작았으며, 위도별로는 위도가 높아질수록 증가추세가 커졌다. 해안별 특성은 동해안의 증가 추세가 가장 크고 남해안의 증가 추세가 가장 작았으며 이는 해안의 고도차에 따른 영향으로 판단된다. 위도증가에 따라 내륙의 평균 증가폭은 해안 전체의 평균 증가폭과 비슷했다. 경도별로는 내륙에서 태백산맥에 해당하는 부분이 가장 큰 증가추세를 보였다. 도시화 지역이 비도시화 지역에 비하여 상대적으로 큰 증가추세를 보였다. 증가추세는 전반적으로 고도와 위도가 증가할수록 증가추세가 뚜렷하고 통계적으로 유의한 것으로 나타났다.

• The Korean Journal of Ecology
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• 제12권4호
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• pp.245-256
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• 1989

Nitrogen cycling was in vestigated in Piuns koraiensis plantations with different ages, 1, 2, 3, 6, 9 and 11 years, which were reforested after clear-cutting. Annual N input by bulk precipitation was 10kg., and output by runoff decreased as the plantation aged, especially in-N. The standing N content of the whole vegetation increased approximately 5 times through 11 years. Understory surpassed P. koraiensis plants in the distribution of standing N content for the initial 9 years, but reversed thereafter. Annual N uptake of P. koraiensis plants increased greatly through 11 years, but that of understory increased somewhat until 9 years and decreased thereafter. The maximum N uptake of the whole vegetation was made in the 9-yr-old plantation. In the 1-yr-old one, 59% of the maximum was already absorbed by understory which mainly consisted to herbs. The recycling coefficient, ratio of annual return to rptake, of the whole vegetation decreased as the plantation aged and the value of understory was greater than that of P koraiensis plants. On the contrary, the N use efficiency, ratio of the net primary production to N uptake, of the whole vegetation increased as the plantation aged and the value of understory was less than that of P. koraiensis plants. Consequently, it is emphasized that understory played an important role in such plantation reforesred after clear-cutting for the initial 9 years.