• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.183-186
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• 2008

All measures to cope with flooding rely on flood predictions to some extent, and the effectiveness of these measures is dependent on the quality of flood predictions. It is important to track properly the movements of the river-bankline in numerical modeling because the location of it varies continuously in the flood inundation. In this study, the wet and dry treatment is used to describe the moving river-bankline accurately (Cho, 1996). An oscillatory flow motion in a parabolic basin is used to validate the performance of the developed model based on quadtree grids. As a result of a simulation, a reasonable agreement is observed with analytical and Cho's results.

• Journal of Environmental Science International
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• v.21 no.4
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• pp.471-478
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• 2012

In this study, the flow characteristic analysis at the curved-channel of the actual channel section is compared and reviewed using the 2D RMA-2 model and the 3D FLOW-3D model. the curve section with curve rate 1.044 in the research section is analyzed applying the frequency of he project flood of 100 years. According to the result, the issue for the application of the FLOW-3D Model's three-dimensional numeric analysis result to the actual river is found to be reviewed with caution. Also, application of the 3D model to the wide basin's flood characteristic is determined to be somewhat risky. But, the applicability to the hydraulic property analysis of a partial channel section and the impact analysis and forecast of hydraulic structure is presumed to be high. In addition, if the parameters to reflect the vegetation of basin and the actual channel, more accurate topological measurement data and the topological data with high closeness to the current status are provided, the result with higher reliability is considered to be drawn.

• Journal of Environmental Science International
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• v.24 no.4
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• pp.359-369
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• 2015

This study analyzed the velocimetry of runoff and measured the flood discharge by applying the SIV (Surface Image Velocimetrer) to the daytime and nighttime flow image data with special reference to Seong-eup Bridge at Cheonmi stream of Jeju during the flow by the severe rainstorm on May 27, 2013. A 1000W lighting apparatus with more than 150 lux was installed in order to collect proper nighttime flow image applied to the SIV. Its value was compared and analyzed with the velocity value of the fixed electromagnetic wave surface velocimetry (Kalesto) at the same point to check the accuracy and applicability of the measured velocity of flow. As a result, determination coefficient $R^2$ values were 0.891 and 0.848 respectively in line with the velocity distribution of the daytime and nighttime image and the flow volume measured with Kalesto was approximately 18.2% larger than the value measured with the SIV.

• Water for future
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• v.29 no.1
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• pp.163-179
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• 1996

Flood flow characteristics of the Han River (from Goan to Indo Bridge) are analyzed using 1-dimensional St. Venant equations. NETWORK, a finite difference model, is used to calculate each term (local acceleration term, convective acceleration term, pressure force term, gravity force term, and friction force term) of the momentum equation and to analyze the flow characteristics. By the result of the study, as the general characteristics of flow in a channel that acceleration terms are very small and the other three terms are much greater is presented, three terms(pressure force term, gravity force term, friction force term) are to be main terms which decide the characteristics of flow. Specially in this region the acceleration term is noted so large that it cannot be ignored according to the shape of hydrograph and the region.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.437-441
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• 2009

The modern times is as special as from the river, the river is very important of our life. The importance to preserve the river environment has been issued and the river developing method is being changed to use potential function of nature as well as flood control. Essential element of the river restoration is a vegetation. The flow resistance by vegetation along the river banks is greatly increase the flood stage. Therefore, the flow resistance due to vegetation in the river and roughness coefficient changes to understand the hydraulic characteristics is an important elements in the river restoration. The purpose of this study is to analyze the flood stage and the aspects of riverbed changes due to the corridor restoration with river vegetation. In order to simulate the flood stage and riverbed changes, HEC-RAS, RMA-2, and SED-2D model were applied for the upstream and downstream in study reaches, respectively.

• Journal of Wetlands Research
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• v.19 no.3
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• pp.335-344
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• 2017

In this study, We proposed a method to estimate the design flood by area ratio in an ungauged basin. For that, the discharge parameters was determined by calibration of observed data at the watershed outlet and then peak flow was estimated by area ratio. In order to verify suggested method, peak flow was compared the observed discharge of the small river basin and the design flood discharge of river implementation projects. The results were summarized as follows. As a result of comparing the discharge by the area ratio and observed discharge, the difference of peak flows were analysed 14 ~ 25%. When the discharge calculated with area ratio of small river was compared with the design flood discharge of river implementation projects, the relative error was analyzed to be less than 20%. It means that suggested method in this study is appropriate.

• Spatial Information Research
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• v.11 no.2
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• pp.155-170
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• 2003

Flood inundation analysis system using GIS has been developed to simulate inundation in airport drainage areas. The model developed in this study has been synthetically presented and constructed the preprocess for database construction and input data preparing through a graphic user interface, GUI system and the postprocess processing graphically output resulted in mainprocess analysis model linked GIS(ArcView/Avenue). The mainprocess analysis model was simulated in real phenomenon caused by inflow of storm sewer system by simulation flooding due to backwater effect and surcharged flow in storm sewer system by simulating interaction coupling the overland flow analysis model and storm sewer system analysis model. In the future, the flood inundation analysis system developed in this study will be a great contribution to systematic decision-making for establishing the flood-mitigation management and facilities improvement plan to flooding damage in airport.

• Journal of the Korean association of regional geographers
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• v.14 no.2
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• pp.105-113
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• 2008

The purpose of this paper is to analyze the influences of extreme flood on urban stream's habitat environment at Shincheon stream in Daegu. In case of Shincheon stream, as any extreme floods have not flowed over the artificial bank, an extreme flood have an effects on inner part of confined channel. To make riparian park along Shincheon channel, Concrete and rubber weirs are constructed. These weirs interrupted flow of running water as obstacles during extreme flood, and running water moved aside into and destructed banks of lower-flow-channel. In reach of no weir, as all small-scale topographic bedforms were eliminated, habitat environment of river ecosystem was simplified, and biodiversity of river ecosystem was decreased. As simplified riverbed become irregular bedforms through frequent small-scale-floods, river ecosystem will become vigorous.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.1460-1461
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• 2005

• Magazine of the Korean Society of Agricultural Engineers
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• v.9 no.1
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• pp.1277-1279
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• 1967