• Journal of Environmental Science International
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• v.17 no.2
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• pp.239-248
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• 2008

The purpose of this study is to examine appropriate sub-basin division numbers that best reflect the hydrological characteristics of the basin so as to propose the criterion for dividing the sub-basin in analyzing flood runoff in the future. The characteristics of flood runoff variations were based on the WMS HEC-1 model, and the area in the upstream of the Dongbyeon water level observatory and the Geum-ho water level observatory was chosen for analysis, and examined the characteristics of the changes in flood runoff. First of all, in the targeted basin, if the sub-basin division number was 4 (that is, the area of the divided sub-basin was about 25% of the total area). Next, as the sub-basin division number gradually increased, the peak rate of runoff increased as well, and in case the sub-basin was not divided, the peak rate of runoff occurred at the earliest time. Given these results, the spatial change characteristics will be best reflected when the sub-basin is divided for analysis of flood runoff in such a way that the area of the divided sub-basin is about 25% of the total area of the basin. However, as these results are based on a limited number (4) of storms, more storm events and other basins need to be included in the review of the sub-basin division methodology.

• Journal of the Korean association of regional geographers
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• v.4 no.1
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• pp.121-134
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• 1998

In this study, the satellite images and the GIS technique are used to select the basin characteristics parameters as the basis of water resources management of river basin. The study area is Geum-ho river basin and the hydrologic characteristics data are computed through the database of the basin characteristics parameters classified by subjects with 35 maps correspond to the study basin of 1:25,000 scale as the basic map. As the result, the drawing up of land use map through satellite image processing that provides the quantitative informations for the land is very efficient to analysis the extensive land use information of the basin, and exact analysis of mass surface data is possible and the feasibility of statistic computation between spatial subjects as it superpose on other subject map is ascertained. It is thought also that the analysis of the basin characteristics data can be utilized very effectively for the basin management and the analysis of basin surface area, once it is expressed numerically for database, since the superposition analysis with different subject map and the correlative analysis with the property data are possible although the tracing process of each subject in the basic map is not efficient. Especially, modification and renewal of the data for the change of land surface become easy, therefore more rapid and exact selection of the basin characteristics data and the construction of more efficient basin management plan are possible.

• Journal of Environmental Science International
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• v.15 no.9
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• pp.887-895
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• 2006

Through this research of the analysis on the frequency flood discharges regarding basin property factors, a linear regression system was introduced, and as a result, the item with the highest correlation with the frequency flood discharges from Nakdong river basin is the basin area, and the second highest is the average width of basin and the river length. The following results were obtained after looking at the multi correlation between the flood discharge and the collected basin property factors using the data from the established river maintenance master plan of the one hundred twenty-five rivers in the Nakdong river basin. The result of analysis on multivariate correlation between the flood discharges and the most basic data in determining the flood discharges as basin area, river length, basin slope, river slope, average width of basin, shape factor and probability precipitation showed more than 0.9 of correlation in terms of the multi correlation coefficient and more than 0.85 for the determination coefficient. The model which induced a regression system through multi correlation analysis using basin property factors is concluded to be a good reference in estimating the design flood discharge of unmeasured basin.

• Journal of Environmental Science International
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• v.9 no.3
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• pp.193-199
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• 2000

This study is carried out the analysis of the runoff characteristics for the design of the interior drainage systems by SWMM in urbanization basin. The basin analyzed in this study is Bumuh-chun basin which is located in Susung-gu of Taegu city. Huff method is used for rainfall distribution analysis. The optimal rainfall duration in Bumuh-chun basin is analyzed as about 90 minutes decided from comparison of arrival time and critical duration. Flood flow variation pattern is proposed through the comparison of the results of peak flow and peak time analyzed by SWMM about pre-urbanization and post-urbanization of Bumuh-chun basin. It is known that the variation of arrival time caused by the rapid increase of pavement rate in the upper area shows about 20∼25 minutes faster than pre- urbanization. Therefore, the management of surface water for design of water supply and drainage, and channel alteration has to considered the variation of geological factors according to urbanization.

• Journal of the Korean association of regional geographers
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• v.7 no.4
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• pp.93-104
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• 2001

The purpose of this study is to analyze the geomorphic characteristics of two erosional basins with same geological conditions. The study areas, the Okcheon basin ($36^{\circ}\;14'{\sim}36^{\circ}\;20'\;N,\;127^{\circ}\;32'\;30"{\sim}127^{\circ}\;37'\;37"\;E$) and Jincheon basin($36^{\circ}\;48'{\sim}37^{\circ}\;03'\;N,\;127^{\circ}\;22'{\sim}127^{\circ}\;36'\;E$), are located on middle part of the Geum river. The geological maps, a summit level map, and a drainage network map are created and analyzed the geomorphic characteristics. The main results are as follows: 1) The Okcheon basin and Jincheon basin are typical erosional basin, in which basin floor are composed of granite. 2) The formation of Okcheon basin and Jincheon basin resulted from differencial erosion after upwarping. 3) Okcheon basin and Jincheon basin are available for specialized agriculture area and a site of new settlement with satisfactory to accessibility.

• Proceedings of the Korea Water Resources Association Conference
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• 2003.05b
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• pp.611-614
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• 2003

Yi-dong experimental basin is operated for research on the rural basin characteristics and accumulation of a long term data by hydrological observation equipments. It is basin area 9,440ha, length 14.4km and slope 0.67%. Hydrological observation network is constructed of rainfall meter 4points, reservoir storage level 3points and river water level 2points.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.34-40
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• 1998

The existing flood runoff models, Complex Hydrograph and HEC-1, have some problems which do not properly represent runoff characteristics on the Korean paddy basin and their basin slopes. In this study, FAS(Flood Analysis System) was developed in order to supplement those problems, which was built calibrating runoff curve number for paddy basin and applying basin slopes to classify 5 levels. And also the FAS can synthesize the flood hydrographs of subbasin and analyze flood routing along a stream. To verify the applicability of the FAS, the computed flood hydrographs were compared with the observed hydrographs from the four watersheds. In the small basin smaller than 10$\textrm{km}^2$, the results of the FAS did not completely agree with the observed ones due to concentration time delay of paddy storage effect while in the medium and large size basin showed good agreements between the observed and computed ones. Therefore, it was concluded that the FAS could be applied for the flood analysis of Korean watershed which was characterized by paddy storage effect.

• Journal of The Geomorphological Association of Korea
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• v.24 no.2
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• pp.41-49
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• 2017

From the results of the CIA analysis (A-CN-K and A-CNK-FM ternary diagram), we concluded that granitic grus experienced low chemical alteration and contains plenty of sandy material The chemical alteration of Geochang and Gajo Basin advanced further than that of Yeongju-Bonghwa basin, but does not come to spatial differentiation as Chuncheon Basin. The weathered mantles of inner hills in the basin exhibit very weak alteration, and there is little spatial differentiation of chemical alteration between footslope of mountains, footslope hills. Most of hills are still in incipient weathering stage and have plenty of sandy materials. Therefore the chemical characteristics of granitic hills in Geochang and Gajo basin show that granitic weathered mantles are not saprolite formed by alteration but may be just grus (sandy weathered mantles).

• Magazine of the Korean Society of Agricultural Engineers
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• v.38 no.5
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• pp.64-73
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• 1996

When typhoon occurs, the meteorological conditions get worse and can cause a large damage from storm and flood . This damage, however, can be minimized if a precise analysis of the runoff characteristics by typhoon tracks is used in the flood contorl This paper aims at the analysis of storm occurrence and runoff characteristics by typhoon tracks in Nakdong river basin. Therefore, the data of 14 typhoons which invaded Nakdong river basin during the period from 1975 to 1991 were collected, analyzed, and studied. The major results of this study are as followings; 1) The frequency of the typhoon occurrence here in Korea was affected by the storms three times a year on the average. The highest-recorded frequency was during the months of July to September. 2) The survey of the track characteristics depending on the forms of the storm in the Nakdong river basin showed that typhoon storm advanced from the south of the basin to the north, while the frontal type storm was most likely to advanced from the west to the north. 3) Typhoon tracks are classified into three categories, 6 predictors with high correlation coefficient are finally selected, and stepwise multiple regression method are used to establish typhoon strom forecasting models. 4) The riview on the directions of progress of the storm made it clear that the storm moving downstream from upstream of the basin could develop into peak discharge for ca short time and lead to more flood damage than in any other direction.

• Journal of The Geomorphological Association of Korea
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• v.23 no.3
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• pp.57-66
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• 2016

The objective of this study is to find out geomorphological characteristics of historical ruins where people produced and consumed large jar coffins excavated in the Yeongsan river basin using the map of old drainage network to restore distribution network. For this purpose, we chose the 21 consumption sites. The results are as follows. First of all, large jar coffins(relics, 47.6% of total) in the Yeongsan River basin were located in Sampo stream basin, almost all of them were located within the Yeongsan River main stream basin and Sampo stream basin. Also, distance from all consumption site to river was within about 2km. Therefore, it is thought that the all consumption sites are located at the place of the gift of nature that was very favorable to water transport of jar coffins. The results of this study may be used as basic data for research of cultural relics in the Yeongsan river basin.