• The Journal of the Korea Contents Association
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• v.9 no.11
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• pp.465-474
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• 2009

To measure the amount of nonpoint source pollution, some efforts are tried to utilize satellite imagery. But, as the factors for water models do not relate with the landcover categories for satellite imagery, satellite imagery are adapted to roughly classified thematic map or used only for the image interpretation. The purpose of this study is to establish the landcover categories of satellite imagery to relate with the water models. To establish the categories of the landcover for the water models, it was investigated to get main factors of water flow models for the nonpoint source pollution and to review the existing study and the classification system. For this result, it was convinced that the basic unit on the nonpoint source pollution, landcover coefficients of SCS Curve Number, the crop factor of Universal Soil Loss Equation, Manning's roughness coefficients are the useful parameters to extract information from the satellite imagery. After the setup the categories for the landcover classification, it was finally defined from the consultation of the water model specialist. Woopo wetland watershed was selected to the study area because it is a representative wetland in Korea and needs the management system for nonpoint source pollution. There were used Landsat ETM Plus and SPOT-5 satellite imagery to assess the result of the image classification.

• Korean Journal of Weed Science
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• v.2 no.2
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• pp.129-140
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• 1982

Herbicides were classified by two-dimensional ordination analysis based on the weed flora which was not controlled by application of a particular herbicide. The number of herbicide group was varied depending upon the weed community type and the experiment site. The technique of the two-dimensional ordination analysis gave more comprehensive informations about selecting of herbicides for increasing the herbicidal efficacy, for increasing the weed spectrum and for reducing the herbicide cost by mixing of herbicides. The two-dimensional ordination analysis could be used not only herbicide classification and selecting effective herbicide or herbicide combination but also can be used for the evaluation of systematic application of herbicides.

• Journal of the Korean Geographical Society
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• v.47 no.2
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• pp.193-207
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• 2012

This study discussed characteristics of Shindu Coastal Dune as habitat, and relationship between geodiversity and biodiversity. It was identified spatio-temporal variation of incoming nutrients depended on geomorphic differences of foredunes. The main incoming path of nutrients into coastal dune was considered as influx with movement of wind blown sands from the beach and tidal f lat. Concentrations of Na, Mg, K, Ca, and P in blown sands were compared. Concentrations of Na, Mg, and K showed high and irregular pattern in favorable condition of influx of blown sand. So these nutrients were related with geomorphic characteristics of foredunes. However, Na was also influenced by other factor such as salt spray. P was independent from effects of sea water and blown sands. In the case of Ca, a large coastal dune system rather than localized forms of foredunes made differences in the variation. Due to differences in spatio-temporal variation of nutrients, patterns of major vegetation could be inferred to appear differently. This study shows geomorphic dynamics of coastal dunes as habitat, and will provide information for coastal dune management and for understanding biological distribution and growth pattern in coastal dune.

• Spatial Information Research
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• v.21 no.2
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• pp.55-71
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• 2013

This study assessed the thermal comfort of new towns in the Seoul Metropolitan Area (Ilsan, Bundang, Dongtan1) using PET (Physiologically Equivalent Temperature) which refers to real human heat stress. The relationship between PET and urban spatial elements was also analyzed using multiple regression analysis. The study results show that the thermal comfort of Dongtan 1, which is considering a reduction of the urban heat island effect in the planning phase, is higher than other cities. In addition, through regression results, the impervious ratio, floor area ratio, commercial area ratio, and residential area ratio were found to be major factors increasing PET. Moreover, the river area ratio and NDVI were found to be major factors decreasing PET. This study has scientific significance as research that focuses on the assessment of thermal comfort scientifically and definitely, by estimating PET for an entire urban area using GIS analysis that included remote sense analysis and the wind field model. The results of this study can be used in preparing more effective urban plans for the promotion of citizen thermal comfort.

• Korean Journal of Remote Sensing
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• v.36 no.5_2
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• pp.975-988
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• 2020

Change detection is the process of identifying changes by observing the multi-temporal images at different times, and it is an important technique in remote sensing using satellite images. Among the change detection methods, the unsupervised change detection technique has the advantage of extracting rapidly the change area as a binary image. However, it is difficult to understand the changing pattern of land cover in binary images. This study used grid points generated from seamless digital map to evaluate the satellite image change detection results. The land cover change results were extracted using multi-temporal KOMPSAT-3A (K3A) data taken by Gimje Free Trade Zone and change detection algorithm used Spectral Angle Mapper (SAM). Change detection results were presented as binary images using the methods Otsu, Kittler, Kapur, and Tsai among the automated threshold selection algorithms. To consider the seasonal change of vegetation in the change detection process, we used the threshold of Differenced Normalized Difference Vegetation Index (dNDVI) through the probability density function. The experimental results showed the accuracy of the Otsu and Kapur was the highest at 58.16%, and the accuracy improved to 85.47% when the seasonal effects were removed through dNDVI. The algorithm generated based on this research is considered to be an effective method for accuracy assessment and identifying changes pattern when applied to unsupervised change detection.

• Korean Journal of Remote Sensing
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• v.31 no.2
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• pp.149-160
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• 2015

A comparative study was conducted for alternative consecutive procedures of detection of cloud-contaminated pixels and gap-filling and smoothing of time-series data to produce high-quality gapless satellite vegetation index (i.e. Normalized Difference Vegetation Index, NDVI). Performances of five alternative methods for detecting cloud contaminations were tested with ground-observed cloudiness data. The data gap was filled with a simple linear interpolation and then, it was applied two alternative smoothing methods (i.e. Savitzky-Golay and Wavelet transform). Moderate resolution imaging spectroradiometer (MODIS) data were used in this study. Among the alternative cloud detection methods, a criterion of MODIS Band 3 reflectance over 10% showed best accuracy with an agreement rate of 85%, which was followed by criteria of MODIS Quality assessment (82%) and Band 3 reflectance over 20% (81%), respectively. In smoothing process, the Savitzky-Golay filter was better performed to retain original NDVI patterns than the wavelet transform. This study demonstrated an operational framework of gapdetection, filling, and smoothing to produce high-quality satellite vegetation index.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.961-965
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• 2007

현재 오염총량관리제를 시 군 단위의 기초자치 단체별로 시행하고 있는데 실제로 오염물질의 전달은 행정구역단위가 아닌 유역내에서 이루어지진다. 따라서 본 연구에서는 기초자치 단체별이 아닌 유역단위로 오염부하량과 삭감량을 산정함으로써 유역 단위의 오염총량관리제 계획 수립을 위한 토대를 제공하고자 한다. 본 연구에서는 보청천 유역을 대상으로 유역의 오염부하량을 산정하고자 하였다. 이를 위하여 지리정보시스템(GIS)인 WMS(Watershed Management System)와 ArcView를 이용하여 유역의 지형인자들을 추출하고, 각 소하천의 토지이용도와 생활계, 축산계, 양식계, 토지계를 바탕으로 원단위를 적용하여 발생부하량을 산정하였다. 그리고 각 소하천별 발생부하량 산정 결과를 토대로 각 수질관측점을 기준으로 하여 배출부하량을 산정하였으며, 배출부하량의 산정결과를 이용하여 유달부하량을 산정하였다. 이를 위해서 필요한 수질 데이터는 QUAL2E 모형을 이용하여 모의 하였으며, 수리 및 수질 매개변수를 추정하고 모형의 보정 및 검증을 수행하였다. 그 결과 유달부하량은 BOD는 2013.16kg/일, TN은 1091.34kg/일, TP은 235.16kg/일이 도출되었다. 따라서 장래에 수질이 악화될 경우를 고려하여 수질 항목별 오염량이 2배, 3배로 증가한다고 가정하였다. 오염량이 2배 증가하였을 경우, 오염부하량을 산정한 결과 보청천3 지점에서 BOD는 184.68kg/일이 삭감되어야 하고, 오염량이 3배 증가하였을 경우 BOD는 1775.69kg/일이 삭감되어야 한다는 결과를 도출할 수 있었다. 본 연구와 같이 유역단위로 오염부하량을 산정할 경우, 오염원을 줄이는데 효율적일 것으로 생각되며, 향후 오염총량관리제를 위해 유역단위의 오염부하량 산정을 고려하면 좋을 것으로 사료된다.는 지배적인 요인으로 남게 될 것이다. 본 연구에서는 현재 진행중인 승기천 오염하천 정화사업이 종료되는 시점을 기준으로 남동유수지에 대해 승기천과 연계한 유수지의 환경개선 방법을 제안하였다. 준설을 통해 유수지의 근본적인 오염원을 제거하고 남동유수지 유입부에 인공습지와 수처리설비를 설치하여 유수지의 수질을 개선하고 개선된 수질이 3급수로 유지하도록 하였으며, 설치된 인공습지에는 철새도래지를 조성하여 유수지 유입수인 철새가 날아드는 하천인 승기천의 테마와 연계하도록 하였다. 인공습지 주변으로 식생호안을 설치하고 유수지 주변에는 산책로를 설치하여 지역주민들의 친환경 수변공간으로 활용하도록 하였다. 1유수지와 연결된 2유수지는 BTL사업을 통해 주변공단으로부터의 오폐수를 원천적으로 차단하도록 하였으며 2유수지를 매립하여 지하는 강우시 유출수 저류가 가능한 화물차주차장으로 활용하고 지상은 녹지공간으로 조성하여 공단근로자 및 지역주민을 위한 휴식공간으로 활용될 수 있도록 제안하였다. 본 연구는 남동유수지 환경 개선 사업 실행을 위한 정책 연구로 연구결과를 인천시가 적극 수용하기로 결정함에 따라 인천시의 환경 현안 문제인 남동유수지의 수질개선을 통해 시민의 휴식 및 여가선용 공간으로 활용하기 위한 사업의 기초자료로 활용되며 이미 설계검토가 시작되었다. 본 연구결과는 유수지 및 저수지의 환경개선 사업의 선두적인 성공사례로 국내 타 지역의 유사한 사업에 있어 벤치마킹을 할 수 있는 훌륭한 사례가 될 것이다.요 생산이 증가하자 군신의 변별(辨別)과 사치를 이유로 강력하게 규제하여 백자의 확대와 발전에 걸림돌이 되었다. 둘째, 동기(銅器)의 대체품으로 자기를 만들어 충당해야할 강제성 당위성 상실로 인한 자기수요 감소를 초래하였을 것으로 사료된다. 셋째, 경기도 광주에서 백자관요가 운영되었으므로 지방인 상주

• Economic and Environmental Geology
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• v.48 no.6
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• pp.501-508
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• 2015

The purpose of this study is to provide an inquiry into paleovegetation (paleoenvironment), eruption age and inferred emplacement temperature of pyroclastic deposit using charcoal occurred in the Quaternary Nari Caldera, Ulleung Island. In order to obtain the data, we carried out species identification and tree-ring analysis, radiocarbon dating for the charcoal. This sample was collected from pumiceous deposit in lowermost member(Member N-5) of the Nari Tephra Formation, which corresponds to the wood branch that has well preserved the tree-ring structure. Speciation and outermost tree-ring of wood reveal Picea spp. and $263+{\alpha}$ years. The calibrated ages from the center(pith) to the outermost tree-ring are $20,260{\pm}230$, $19,995{\pm}245$, and $19,975{\pm}265cal\;BP$, respectively, which are accordant with the tree-ring position. The youngest age, <19,710 cal BP would have implications for the eruptive age of Member N-5. Our results indicate that Picea spp. is the paleovegetation representing that Nari Caldera was under cold and wet climate conditions during the late Pleistocene. Based on the silky luster, brittleness, color, and streak of charcoal, etc., the lowest emplacement temperatures of pyroclastic flow are interpreted to have been at least as high as $350{\sim}500^{\circ}C$.

• Journal of the Korean Geosynthetics Society
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• v.12 no.3
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• pp.65-73
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• 2013

The information of cut slope in Mt. Jang area, Busan is investigated in order to construct the Slope Management System in Urban Area. The slope inspection sheet is made to record the characteristics for cut slopes, and that is capable to be inputted slope information systematically. The cut slopes in Mt. Jang area are consisting of 69 slopes. Most of the cut slopes are constructed in cutting slope and retaining wall (CR). The cut slopes located in housing facilities are 46 slopes, and the slopes located in school facilities are 12 slopes. The traverse of cut slopes is mainly ranged from 50 m to 150 m, and the height is mainly ranged from 10 m to 20 m. The slopes combined with soil and rock are mostly distributed. The retaining wall was installed in the toe part of cut slope in order to increase the slope stability, and the additional reinforcement methods including the anchor, drainage, preventing rock fall, shotcrete and vegetation were installed at the toe part of cut slopes.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.2
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• pp.121-131
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• 2007

Despite the close linkage in changes between the ecological and hydrological processes in forest ecosystems, an integrative approach has not been incorporated successfully. In this study, based on the vegetation and hydrologic data of the Gwangneung headwater catchment with the Geographic Information System, we attempted such an integrated approach by employing the Regional Hydro-Ecologic Simulation System (RHESSys). To accomplish this, we have (1) constructed the input data for RHESSys, (2) developed an integrated calibration system that enables to consider both ecological and hydrological processes simultaneously, and (3) performed sensitivity analysis to estimate the optimum parameters. Our sensitivity analyses on six soil parameters that affect streamflow patterns and peak flow show that the decay parameter of horizontal saturated hydraulic conductivity $(s_1)$ and porosity decay by depth (PD) had the highest sensitivity. The optimization of these two parameters to estimate the optimum streamflow variation resulted in a prediction accuracy of 0.75 in terms of Nash-Sutcliffe efficiency (NSec). These results provide an important basis for future evaluation and mapping of the watershed-scale soil moisture and evapotranspiration in forest ecosystems of Korea.