• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1437-1449
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• 2023

The purpose of this study is to analyze whether pervious and impervious areas in urban areas affect tree growth. In order to determine the differences in the growth of six species of trees planted simultaneously, the effects of pervious and impervious surfaces on tree growth were analyzed using the Normalized Difference Vegetation Index (NDVI) produced using Sentinel-2 and sub-divided land cover map from the Ministry of Environment. For this purpose, the Geospatial eXplainable Artificial Intelligence(GeoXAI) concept was applied. As a result of the analysis, the explanatory power of the model was found to be the best when considering the area of land cover included in the 10m range for Pinus densiflora, the 20 m range for Zelkova Serrata, Metasequoia glyptostroboides, and Ginkgo biloba, the 30 m range for Platanus occidentalis, and the 40 m range for Yoshino cherry trees. In addition, the wider the pervious area, the more active the growth of trees,showing a positive correlation, and the wider the impervious area, such as nearby artificial ground, showed a negative correlation with tree growth. This shows that surrounding pervious and impervious areas affect the growth of trees and that the scope of influence varies depending on the tree species.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.2
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• pp.69-76
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• 2009

Infiltration is the process of water penetrating from the ground surface into soil. Infiltration plays an important role on affecting ground water surface and surface flow during rainy season. The amount of infiltration water would be decreased as the urbanization would increase. Such phenomenons would make streamflow decrease or stream run dry. In this study the cumulative infiltration and the infiltration capacity of ground surface have been determined by the field experiment at three sites in the Hankyong National University, Korea. Three type pervious pedestrian blocks of the cumulative infiltration and the infiltration capacity have also been determined at the same site of the ground surface. It has been shown that one of three type blocks in terms of infiltration capacity is almost same as that of ground surface. The Kostiakov type has been adopted to determine the cumulative infiltration and the infiltration capacity for each site. The Horton type has been also adopted to determine the cumulative infiltration and the infiltration capacity. The value of parameter k for each site is determined and soil type would be identified corresponding to the value of parameter.

• Journal of the Korean association of regional geographers
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• v.16 no.6
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• pp.706-723
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• 2010

The impervious surface was frequently employed as a proxy of the total environmental burden in the urban area. The impervious surface was extracted from a satellite image and the GIS (Geographical Information System) database for childhood asthma hospitalizations was generated for a total of 62,136 children using the National Health Insurance database of South Korea. Children living in an impervious environment do result in almost twice as many hospitalizations (26.58%) for asthma, as compared to the sub-urban pervious living (15.82%). Furthermore, the risk zones with persistently high hospitalizations for three years were specifically identified over the impervious sub-district alone. The impervious zone showed a small inter-year variation of hospitalizations (r: 0.937) while the sub-urban pervious fringe was found to display a yearly variation(r: 0.371). The strong temporal autocorrelation means that the impervious areas have frequent long-lived hospitalizations for asthma, thus children living in impervious areas were likely to have had more chronic asthma attacks than those living in pervious areas. These experimental results indicate that an impervious surface as thematic parameter of analysis is a crucial explanatory variable for asthma hospitalizations and its longer persistence among children.

• Journal of Korea Water Resources Association
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• v.45 no.6
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• pp.569-581
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• 2012

The levee is the facility which is constructed along with river for the protection of landside and for passage of water when there is a flood. When the seepage is exposed to the atmosphere on the landside surface of levee, it may eventually lead to levee failure. The seepage water may be removed from the landside surface by a properly designed drainage system. The purpose of the study is to show seepage control effect of a pervious toe drain, and to compare two drainage methods of a pervious toe drain. One is the pervious toe drain suggested by U.S. Army Corps of Engineers (USACE) and the other is that suggested by Japan Institute of Construction Engineering (JICE). The levee model constructed has the following dimension: the base width is 2.6 m; the crest width is 0.4 m; the side slope 1 : 2. The water depth in the riverside is 0.5 m. The shape of the toe drain by USACE is triangular. The shape of the toe drain by JICE is rectangular. They were installed with the base length of 0.4 m. The levee model without the toe drain showed saturation surface on the land side in the experiment but not with the toe drain. The experiment results was applied to a numerical analysis model using SEEP/W to calibrate and verify. The numerical analysis results for 35 cm and 30 cm drain width showed that the drain by JICE is a little bit safer than the drain by USACE. It is also easier to construct the toe drain by JICE. The results in the study would be applied to plan the seepage control for a levee with pervious toe drain.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.2
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• pp.181-187
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• 2009

In this study, a runoff hydrograph and runoff volume were calculated by using the kinetic wave theory for small urban watersheds based on the concept of low impact development(LID), and the effective imperviousness was estimated based on these calculations. The degree of sensitivity of the effective imperviousness of small watersheds to the impervious to pervious area ratio, infiltration capability, watershed slope, roughness coefficient and surface storage depth was then analyzed. From this analysis, the following conclusions were obtained: The effective imperviousness and paved area reduction factor decreased as the infiltration capability of pervious area increased. As the slope of watersheds becomes sharper, the effective imperviousness and the paved area reduction factor display an increasing trend. As the roughness coefficient of impervious areas increases, the effective imperviousness and the paved area reduction factor tend to increase. As the storage depth increases, the effective imperviousness and the paved area reduction factor show an upward trend, but the increase is minimal. Under the conditions of this study, it was found that the effective imperviousness is most sensitive to watershed slope, followed by infiltration capability and roughness coefficient, which affect the sensitivity of the effective imperviousness at a similar level, and the storage depth was found to have little influence on the effective imperviousness.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.499-506
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• 2004

The use of dredged soft marine clay is increasing due to a shortage of coarse material available. This paper presents a stabilization method that can increase shear strength of the surface layer of a dredged clay deposit at dates much earlier than usual. The desiccation of the upper soft 1-2m layer can be accelerated by interrupting water seeping from its bottom with impervious geotextile. Just below the geotextile, enough pervious material is provided so that the underlying deposit can be drained through it. This scheme is proved to be effective through theoretical analysis.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.4
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• pp.131-142
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• 2017

This study aims to create a Local Climate Zone(LCZ) map of Seoul by using World Urban Database and Access Portal Tools(WUDAPT) protocol, and to analyze the characteristics of the Seoul LCZs. For this purpose, training samples of 17 LCZ types were collected by using Landsat images and Google Earth. LCZ Classification and Filtering were performed by SAGA GIS. An ArcGIS was used to analyze the characteristics of each LCZ type. The characteristics of the LCZ types were analyzed by focusing on building surface fraction ratio, impervious surface fraction ratio, pervious surface fraction ratio, building stories and air temperature. The results show that one filtering was found to be most appropriate. While Yangcheongu and Yeongdeungpogu with the higher annual and maximum mean air temperature than other areas have the higher rate of LCZ 3(compact low-rise) and LCZ 4(open high-rise), Jongnogu, Eunpyeonggu, Nowongu and Gwanakgu with the lower value have the higher rate of LCZ A(Dence trees). The values of building surface fraction ratio, impervious surface fraction ratio and building stories of each LCZ were included in the range of WUDAPT for most LCZs. However, the values of pervious surface fraction ratio were out of the range, in particular, in the LCZs 4~6 and 9~10. This study shows the usability and applicability of the WUDAPT methodology and its climate zone classification used in many countries as a basic data for the landscape planning and policy to improve the thermal environment in urban areas.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.3
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• pp.347-357
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• 2015

Baswflow is defined as short term discharge through groundwater caused by rainfall events. Impacts of baseflow is significant on water quality especially where pervious agricultural watershed as groundwater is more vulnerable to the contamination. In this study, the Cheongmicheon watershed was subjected to study to assess the impacts of baseflow on surface water quality, where more than 90% of pollutant load is originated from the livestock raising area, and very high probability of surface water contamination due to the baseflow. To estimate nutrient loading cased by baseflow, NI (Numerical Integration) model and LOADEST (LOADing ESTimation) model were used.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.3
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• pp.219-228
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• 2017

Burial sites are constructed for the purpose of controlling air-born livestock diseases such as avian influenza and foot-and-mouth outbreak. As most of the burial sites are located in the agricultural land use, public concerns are mounting about soil and groundwater contamination. During precipitation events, contaminated baseflows are released from the burial sites into surface waters. Baseflow are therefore required to be managed properly, by monitoring and even by remediation means. We propose each burial sites should be regarded as a point source possibly degrade groundwater, thus be managed in watershed scale for the purpose of surface water quality conservation.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.378-381
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• 2008

The regulating and relaxing targets in the Land Use Regulation and Total Maximum Daily Loads are influenced by Land cover information. For the providing more accurate land information, this study attempted to generate an impervious surface map using KOMPSAT-2 image which a Korea manufactured high resolution satellite image. The classification progress of this study carried out by tasseled-cap spectral enhancement through each class extraction technique neither existing classification method. KOMPSAT-2 image of this study is enhanced by Soil Brightness Index(SBI), Green vegetation Index(GVI), None-Such wetness Index(NWI). Then ranges of extracted each index in enhanced image are determined. And then, Confidence Interval of classes was determined through the calculating Non-exceedance Probability. Spectral distributions of each class are changed according to changing of Control coefficient(${\alpha}$) at the calculated Non-exceedance Probability. Previously, Land cover classification map was generated based on established ranges of classes, and then, pervious and impervious surface was reclassified. Finally, impervious ratio of reclassified impervious surface map was calculated with blocks in the study area.