• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3D
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• pp.407-415
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• 2008

This study presents the methodology to link with aerial photos for advancing the accuracy of topographic survey data that is used to calculate water volume in urban stream. First, GIS spatial interpolation technique as Inverse Distance Weight (IDW) and Kriging was applied to construct the terrain morphology to the sand-bar and grass area using cross-sectional survey data, and also validation point data was used to estimate the accuracy of created topographic data. As the result of comparison, IDW ($d^{-2}_{ij}$, 2nd square number) in Sand-bar area and Kriging Spherical model in grass area showed more efficient results in the construction of topographic data of river boundary. But the differences among interpolation methods are very slight. Image classification method, Minimum Distance Method (MDM) was applied to extract sand-bar and grass area that are located to river boundary efficiently and the elevation value of extracted layers was allocated to the water level point value. Water volume with topographic data from aerial photos shows the advanced accuracy of 13% (in sand-bar) and 12% (in grass) compared to the water volume of original terrain data. Therefore, terrain analysis method in river linking with aerial photos is efficient to the monitoring about sand-bar and grass area that are located in the downstream of Dam in flooding season, and also it can be applied to calculate water volume efficiently.

• Journal of Wetlands Research
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• v.22 no.3
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• pp.194-199
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• 2020

Unlike in the past, the world is facing water shortages due to climate change and difficulties in simultaneously managing the risks of flooding. The Four Major Rivers project was carried out with the aim of realizing a powerful nation of water by managing water resources and fostering the water industry, and the construction period was relatively short compared to the unprecedented scale. Therefore, the prediction and analysis of how the river environment changes after the Four Major Rivers Project is insufficient. Currently, part of the construction section of the Four Major Rivers Project is caused by repeated erosion and sedimentation due to the effects of sandification caused by large dredging and flood-time reservoirs, and the head erosion of the tributaries occurs. In order to solve these problems, the riverbed maintenance work was installed, but it resulted in erosion of both sides of the river and the development of new approaches and techniques to keep the river bed stable, such as erosion and excessive sedimentation, is required. The water agent plays a role of securing a certain depth of water for the main stream by concentrating the flow so much in the center and preventing levee erosion by controlling the flow direction and flow velocity. In addition, Groyne products provide various ecological environments by forming a natural form of riverbeds by inducing local erosion and deposition in addition to the protection functions of the river bank and embankment. Therefore, after reviewing the method of determining the shape of the Groyne structure currently in use by utilizing the mobile limit flow rate and marginal reflux force, a new Critical Movement Velocity(${\bar{U}}_d$) and a new resistance coefficient formula considering the mathematical factors applicable to the actual domestic stream were developed and the measures applicable to Groyne installation were proposed.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.2
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• pp.64-71
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• 2012

This is a basic study for recovering original form of Nongsanbyeoleop(農山別業) in Gangjin, Jeonnam, created in the latter part of Joseon period and the estimation of originla form at the time of creation was conducted by analyzing related literature and inspecting the actual site. "Joseokruki(朝夕樓記)" of Dasan Jung, Yak Yong could estimate spatial structure and using form of Nongsanbyeoleop and the arrangement of spatial structure in literature could be confirm by on-the-site inspection. The results of this study are as follows. The first, Nongsanbyeoleop managed spatial factors applying natural topography. For the spatial characteristics of Nongsanbyeoleop, the location of ancestral ritual space including deceased father's tomb and tomb house far from the main levee of Yun, Kwang Taek, a father of Yun, Seo Yu by 1.9km and housekeeping could be confirmed. The second, spatial estimation by "Joseokruki" could be possible. "Joseokruki" describes Joseokru.Youngmojae.Hanokkwan.Cheokyunjung.Sangam as construction factors, Wundang.Kookdan.Nokwunoh. as plant factors, Sookyunggan.Keumkoji.Nokeumjung.Uijanghae as hydroponic factors and Pyoeunkok.Aengjakang as natural topography factors. However, most of them were disappeared and at present, only Youngmojae, Keumgoji, Kukdan and Wundang show the past trace. The third is for the changed space of Nongsanbyeoleop and its reason. The surrounding space of Nongsanbyeoleop was planated by land arrangement in 1960s and it played a role of topographical damage because it's recognized as the plane factor including Nongsanbyeoleop's surrounding landscape rather than dotted factor. The forth, the actual measurement of Nongsanbyeoleop and digitalization of manual map of numerical value are judged to be sufficient to apply as the basic material for recovering garden in the future. Because of the diatahce changing method applied at that time, the garden recovery of Nongsanbyeoleop intended to be concreted and 3D model established by digitalized basic materials is considered to apply for multilateral studying. Thus, Nongsanbyeoleop which is byeolseo including the tomb of deceased father based on the conceptual hyo thought shows clear differences from the organized factors of Byolseowonrim of precedent studies and the importance of Byolseowonrim is sufficient. But, the constructional factors which cannot know disappeared spatial factors and accurate location became the limitation of this study. In the future, clear verification of original form must be progressed by excavation which can confirm the location of construction factors.

• Ecology and Resilient Infrastructure
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• v.7 no.4
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• pp.262-273
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• 2020

Amending biopolymers such as β-glucan (BG) and Xanthan gum (XG) generally enhances soil strength by ionic and hydrogen bonds between soil particles. Thus, biopolymers have been studied as eco-friendly construction materials in levees. However, physiological responses of plants grown on soil amended with biopolymers are not fully understood. This study focuses on the effects of biopolymers on the growth of Camelina sativa L. (Camelina) under excess zinc (Zn) stress. The optimal concentrations of BG and XG were confirmed to have a 0.5% ratio in soil depending on the physiological parameters of Camelina under excess Zn stress. The Zn binding capacity of biopolymers was investigated using 1,5-diphenylthiocarbazone (DTZ). The reduction of Zn damage in Camelina was evaluated by analyzing the Zn content and expression of heavy metal ATPase (HMA) genes under excess Zn stress. Amendments of BG and XG improved Camelina growth under excess Zn stress. In DTZ staining and ICP-OES analysis, Camelina grown on BG and XG soil showed less Zn uptake than normal soil under excess Zn stress. The Zn-inducible CsHMA3 gene was not stimulated by either BG or XG amendment under excess Zn stress. Moreover, both BG and XG amendments in soil exhibit Zn-stress mitigation similar to that of Zn-tolerant CsHMA3 overexpres sed Camelina. These results indicate that biopolymer-amended soils may influence the prevention of Zn absorption in Camelina under excess Zn stress. Thus, BG and XG are proven to be suitable materials for levee construction and can protect plants from soil contamination by Zn.

• Journal of Korea Water Resources Association
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• v.42 no.2
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• pp.141-148
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• 2009

Each river in each country has peculiar channel characteristics at every section. Korea consists of mountains at the rate of 70%. Due to this, the sections that display unique channel form are scattered. One of the typical features is the narrow pass of channel section that presents in the process of the generation of alluvial channel and deformation channel. Around as this narrow pass of channel, it often comes to be regular flood disaster section. Regardless of this situation, investigations and plans that reflect channel characteristics at the narrow pass of channel have been wholly wanting until now. In accordance with this, we have investigated and analysed hydraulic significance and channel form of the narrow pass of channel in Seonsan in this study. The study has found real minute classification of sediment phenomenon at river bed of low flow channel on investigation section which is sand-bed river, but it was vaguely difficult to conclude that classification of sediment arises from explicit natural force. We were able to assume that the phenomenon comes from gentle bed slope, supply of river bed materials which is nearly uniformity. However, classification of sediment would come from collecting an aggregate rather than natural force. And we found that compound cross section conversion has been developing dramatically with channel form of movable bed section referring to movement which was active before at drainage district of the narrow pass of channel. With this, we could find the phenomenon that river width of low flow channel diminished largely. This kind of situation implies that it may cause compound section weighting, flood dimension decreasing, revetment at low flow channel or the local scour at bottom of levee when extraordinary flood occurs.