• Proceedings of the KAIS Fall Conference
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• 2010.11b
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• pp.1033-1036
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• 2010

Since Jeju island has depended a water resource on the underground water because of a poor development of the surface flow, Jeju island is in need of the surface resource development to prevent the future shortage of the underground water due to excessive development and use of it. The study shows that the SWAT model(continuous rainfall-runoff model) is applied to estimate the outflow in the drainage watershed area, where it has been urbanized through the change of the land, such as a tourism development, cultivation, housing, and impervious layer road development. Near watershed area in Jeju island, weather and topographical SWAT input data were collected, and compared the outflow change of past and present.

• Journal of Korean Society for Geospatial Information Science
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• v.10 no.2 s.20
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• pp.67-75
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• 2002

Recently, GIS tend to be studied in water resoruces field. In hydrology analysis, GIS propose way that can develop subjective element of designer objectively. The development project is conducting disaster effect estimation to breed disaster, and cope these disaster beforehand provoking soil erosion and food recently. In this study, receive value of LS factor through DEM data at volume of soil erosion computation by disaster effect estimation and whether it are some relation effect of gradient and change of soil erosion by grid size did comparative analysis. As a result, according as grid size great, gradient became slow and could know that error value of gradient great according as storing scale of digital topographical map grows.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.13 no.2
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• pp.169-176
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• 2001

The sediment at the majority of fishery harbors located on the east coast of Korea are affccted by the waves and wave-induced currents as the main external force. And the surroundings of the harbors are composed of sandy beaches. Because many harbors are small and their entrances are located in the wave¬breaking zone, they suffer severe siltation and topographical changes. In order to solve the problems, we have to understand the mechanism through estimations and accurate reproduction of the harbor siltation phenomenon. We suggest economically substantial countermeasures for harbor siltation in the small fishery harbors and investigate the preventive effects using a numerical simulation technique.

• Journal of Korea Water Resources Association
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• v.39 no.1 s.162
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• pp.69-77
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• 2006

Songdo beach in Pohang City has suffered from bouts of beach erosion due to various reasons over many years. One of the most controversial issues is the extent of the harbor facilities effect on the beach erosion. In this study, the characteristics of erosion to Songdo beach were reanalysed using historical data and some aerial photos. Specifically, we set test cases based on the history of human modifications to the surrounding area and the topographic change around Songdo beach were investigated by 3D topographical deformation model. In the end, based on the results of these various kinds of investigation, this study found multiple causes of Songdo beach erosion.

• Journal of Environmental Science International
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• v.33 no.7
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• pp.443-452
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• 2024

The recent increase in impermeable surfaces due to urbanization and the occurrence of concentrated heavy rainfall events caused by climate change have led to an increase in urban flooding. To predict and prepare for flood damage, a convenient and highly accurate simulation of rainfall-runoff based on geospatial information is essential. In this study, the storm water management model (SWMM) was applied to simulate rainfall runoff in the Bangbae-dong area of Seoul, using two sets of topographical data: The conventional topographic digital elevation model (TOPO-DEM) and the proposed shuttle radar topography mission (SRTM)-DEM. To evaluate the applicability of the SRTM-DEM for rainfall-runoff modeling, two DEMs were constructed for the study area, and rainfall-runoff simulations were performed. The construction of the terrain data for the study area generally reflected the topographical characteristics of the area. Quantitative evaluation of the rainfall-runoff simulation results indicated that the outcomes were similar to those obtained using the existing TOPO-DEM. Based on the results of this study, we propose the use of SRTM-DEM, a more convenient terrain data, in rainfall-runoff studies, rather than asserting the superiority of a specific geospatial data.

• Journal of Climate Change Research
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• v.8 no.4
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• pp.287-295
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• 2017

This paper provides a mathematical approach for estimating flood risks due to the effects of climate change by developing a one dimensional (1D) hydraulic model for the mountainous river reaches located close to the Yeongwol thermal power plant. Input data for the model, including topographical data and river discharges measured every 10 minutes from July $1^{st}$ to September $30^{th}$, 2013, were imported to a 1D hydraulic model. Climate change scenarios were estimated by referencing the climate change adaptation strategies of the government and historical information about the extreme flood event in 2006. The down stream boundary was determined as the friction slope, which is 0.001. The roughness coefficient of the main channels was determined to be 0.036. The results show the effectiveness of the riverbed widening strategy through the six flooding scenarios to reduce flood depth and flow velocity that impact on the power plant. In addition, the impact of upper Namhan River flow is more significant than Dong River.

• Journal of The Geomorphological Association of Korea
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• v.19 no.3
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• pp.135-142
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• 2012

The map drawn on a scale of 1 to 50,000, modern Korea map drawn on a scale of 1 to 50,000 made by Japanese colonial era in 1910s, is the first topographical map using modern technical method. The map has been mainly used in human activities and geographic viewpoint, recently it is available on various field with recognizing high accuracy. It is especially expected that the map will provide us with lots of information on long-term change of topography in field of coastal area which is built on coastal structure. This study presents a method for analyzing before and after geographic change of coastal structure in independent drift sand system. The reference point to analyze long-term coastal geographic change was selected the map of 1910s.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1B
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• pp.65-77
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• 2008

The effects of climatic changes owing to urbanization, geographical and topographical conditions on annual and monthly FAO Penman-Monteith (FAO P-M) reference evapotranspiration, and energy and aerodynamic terms of FAO P-M reference evapotranspiration were studied. In this study, 21 climatological stations were selected. The statistical methods applied for trend analysis are Spearman rank test, Sen's test, linear regression analysis and analysis of actual variation ratio. Furthermore, the cluster analysis was applied to cluster 21 study stations by considering the geographical and topographical characteristics of study area. The study results indicate that urbanization affects the trend and amount of FAO P-M reference evapotranspiration, energy term and aerodynamic term; however, the result of Sen's test indicates that urbanization does not significantly affect the magnitude of trend (Sen's slope). The energy term increased at study stations located in coastal area; however, decreased at study stations located in inland area. The topographical slope of study area did not significantly influence on the trend of energy term. The aerodynamic term increased in both coastal area and inland area, indicating much significantly increasing trend in inland area, and it was also affected by the topographical slope of the study area.

• Journal of Environmental Science International
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• v.18 no.9
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• pp.1057-1063
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• 2009

Since Jeju island has depended a water resource on the underground water because of a poor development of the surface flow, Jeju island is in need of the surface resource development to prevent the future shortage of the underground water due to excessive development and use of it. The study shows that the SWAT model(continuous rainfall-runoff model) is applied to estimate the outflow in the drainage watershed area, where it has been urbanized through the change of the land, such as a tourism development, cultivation, housing, and impervious layer road development. Near Oaedo watershed area in Jeju island, weather and topographical SWAT input data were collected, and compared the outflow change of past and present.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1415-1417
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• 2003

In this study, as the passing of a year, the changes of tidal flat area in Seohan Bay, North Korea was monitored through using Landsat ETM Data and the ancient topological map. The map to present tidal flat distribution characteristic based on the ancient topographical map (1918) was constructed as GIS DB. In addition, a tidal flat distribution map was estimated by using the satellite images with unsupervised classification method. Even though it is difficult to approach to study area, it was possible to gain the data and to monitor the change of the coast tidal flat by comparing to area change yielded.