• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.580-583
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• 2007

Various matching methods have been introduced by investigators to improve digital elevation model (DEM) accuracy of satellite imagery. This study proposed an area-based matching method according to land cover property using correlation coefficient of pixel brightness value between the two images for DEM generation from IKONOS stereo imagery. For this, matching line (where "matching line" implies straight line that is approximated to complex nonlinear epipolar geometry) is established by exterior orientation parameters to minimize search area. The matching is carried out based on this line. Land cover classes are divided off into water, urban land, forest and agricultural land. Matching size is selected using a correlation-coefficient image in the four areas. The selected sizes are $81{\times}81$ pixels window, $21{\times}21$ pixels window, $119{\times}119$ pixels window and $51{\times}51$ pixels window in the water area, urban land, forest land and agricultural land, respectively. And hence, DEM is generated from IKONOS stereo imagery using the selected matching sizes and land cover map on the four types.

• 한국지리정보학회지
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• 제24권1호
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• pp.12-25
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• 2021

토지피복도는 도시의 확장과 개발에 있어 다양한 분야에서 활용되고 있다. 본 연구는 태화강 수계지역을 중심으로 멀티센서 정보를 이용하여 시계열적 토지피복 변화량을 분석하였다. 정확도가 높은 항공 초분광 영상을 적용하기 위하여 지상분광 스펙트럼과의 패턴을 검토하고, 시계열 수치지형도와 비교하였다. 초분광 영상은 13개의 토지피복 등급을 설정하였고, 시계열 수치지형도는 7개, 그리고 수계지역을 중심으로는 각각 5~6개 등급으로 분류하여 분석하였다. 1990년대에서 2010년까지 수치지형도의 토지피복 변화량 분석결과 산림지역이 빠르게 감소하고 농경 및 초지가 도시화되고 있는 것을 알 수 있었다. 초분광 영상을 통한 수계지역(500m 설정)의 토지피복변화(2010~2019)는 농업, 산림, 초지가 각각 1.4㎢, 1.0㎢, 0.8㎢가 시가지화 건조지역으로 변화되었으며 태화강 수계를 중심으로 도시화가 가속화되고 있음을 알 수 있었다. 최근 고정밀 위성영상과 항공 초분광 영상을 이용하여 토지피복도 제작에 대한 연구가 많이 이루어지고 있기 때문에 더욱 세분화되고 정밀한 토지피복도를 제작하여 활용할 수 있을 것으로 기대된다.

• 대기
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• 제20권4호
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• pp.415-426
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• 2010

A Land cover map over East Asian region (Kongju national university Land Cover map: KLC) is classified by using support vector machine (SVM) and evaluated with ground truth data. The basic input data are the recent three years (2006-2008) of MODIS (MODerate Imaging Spectriradiometer) NDVI (normalized difference vegetation index) data. The spatial resolution and temporal frequency of MODIS NDVI are 1km and 16 days, respectively. To minimize the number of cloud contaminated pixels in the MODIS NDVI data, the maximum value composite is applied to the 16 days data. And correction of cloud contaminated pixels based on the spatiotemporal continuity assumption are applied to the monthly NDVI data. To reduce the dataset and improve the classification quality, 9 phenological data, such as, NDVI maximum, amplitude, average, and others, derived from the corrected monthly NDVI data. The 3 types of land cover maps (International Geosphere Biosphere Programme: IGBP, University of Maryland: UMd, and MODIS) were used to build up a "quasi" ground truth data set, which were composed of pixels where the three land cover maps classified as the same land cover type. The classification results show that the fractions of broadleaf trees and grasslands are greater, but those of the croplands and needleleaf trees are smaller compared to those of the IGBP or UMd. The validation results using in-situ observation database show that the percentages of pixels in agreement with the observations are 80%, 77%, 63%, 57% in MODIS, KLC, IGBP, UMd land cover data, respectively. The significant differences in land cover types among the MODIS, IGBP, UMd and KLC are mainly occurred at the southern China and Manchuria, where most of pixels are contaminated by cloud and snow during summer and winter, respectively. It shows that the quality of raw data is one of the most important factors in land cover classification.

• 한국측량학회지
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• 제2권1호
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• pp.5-16
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• 1984

본 연구는 인공위성(LANDSAT) Data를 이용한 도시역의 토지이용도(피복도)의 작성과 그 경연변화에 관하여 논한 것이다. 구체적으로는 인구증가가 현저한 서울시를 대상으로 1979년과 1983년의 토지피복도를 작성함과 동시에 이들의 4년간에 있어서의 토지피복도의 변화를 고찰하였다. 본 연구에서 개발 정리한 Software와 그 수순을 답습함으로서, 금후 관측수집일이 상이한 LAN-DSAT Data에 대하여 같은 조건으로 도시역에 있어서의 토지피복도의 작성이 가능하게 되었다.

• 대한공간정보학회지
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• 제23권1호
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• pp.15-22
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• 2015

풍력자원지도의 작성을 위해 기본적으로 지형고도자료, 지면조도자료, 풍황자료가 필요하다. 그 중 지면조도자료의 경우 토지피복분류 기법을 통한 토지피복지도를 이용하여 구할 수 있다. 지면조도지도의 경우 토지피복의 성질에 따라 풍속의 조도계수가 다르게 되며, 이러한 조도계수에 근거하여 정확한 지면조도지도를 만들 수 있다. 본 연구에서는 Landsat위성자료를 이용하여 무감독 분류 방법과 식생지수법을 사용하여 지면조도자료를 생성한 후 풍력자원지도를 작성하였다. 이렇게 만들어진 풍력자원지도를 근거로 식생지수법의 사용이 무감독 분류 기법에 비하여 타당한지를 검증하였다. 그 결과, 식생지수를 사용한 풍력자원지도는 관측 자료와 비교한 경과 60% 이상의 등급 일치율을 보였고 불일치하는 픽셀에 대해서는 최대 등급의 차이를 넘지 않았다. 따라서 풍력자원지도 생성 시 필요한 지면조도지도를 계산할 경우 식생지수를 이용한 분류방법이 효과적인 것으로 판단된다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.763-765
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• 2003

We made a hazard map using GIS and remote sensing for he greatest inundation damage that happened for the 20th century. We calculated the land cover classification using Landsat from 1983 to 2000. We calculated it from a damage report and an aerial photo for a flood. We considered relation of both land cover classification and the damage. We expected the inundation damage in the future and made a hazard map.

• 한국물환경학회지
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• 제24권6호
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• pp.690-700
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• 2008

The Soil and Water Assessment Tool (SWAT) model users tend to use the readily available input dataset, such as the Ministry of Environment (MOE) land cover data ignoring temporal and spatial changes in land cover. The SWAT model was calibrated and validated with this land cover data. The EI values were 0.79 and 0.85 for streamflow calibration and validation, respectively. The EI were 0.79 and 0.86 for sediment calibration and validation, respectively. With newly prepared landcover dataset for the Doam-dam watershed, the SWAT model better predicts hydrologic and sediment behaviors. The number of HRUs with new land cover data increased by 70.2% compared with that with the MOE land cover, indicating better representation of small-sized agricultural field boundaries. The SWAT estimated annual average sediment yield with the MOE land cover data was 61.8 ton/ha/year for the Doam-dam watershed, while 36.2 ton/ha/year (70.7% difference) of annual sediment yield with new land cover data. Especially the most significant difference in estimated sediment yield was 548.0% for the subwatershed #2. Therefore it is recommended that one needs to carefully validate land cover for the study watershed for accurate hydrologic and sediment simulation with the SWAT model.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.194-198
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• 2008

Significant soil erosion and water quality degradation issues are occurring at highland agricultural areas of Kangwon province because of agronomic and topographical specialities of the region. Thus spatial and temporal modeling techniques are often utilized to analyze soil erosion and sediment behaviors at watershed scale. The Soil and Water Assessment Tool (SWAT) model is one of the watershed scale models that have been widely used for these ends in Korea. In most cases, the SWAT users tend to use the readily available input dataset, such as the Ministry of Environment (MOE) land cover data ignoring temporal and spatial changes in land cover. Spatial and temporal resolutions of the MOE land cover data are not good enough to reflect field condition for accurate assesment of soil erosion and sediment behaviors. Especially accelerated soil erosion is occurring from agricultural fields, which is sometimes not possible to identify with low-resolution MOD land cover data. Thus new land cover data is prepared with cadastral map and high spatial resolution images of the Doam-dam watershed. The SWAT model was calibrated and validated with this land cover data. The EI values were 0.79 and 0.85 for streamflow calibration and validation, respectively. The EI were 0.79 and 0.86 for sediment calibration and validation, respectively. These EI values were greater than those with MOE land cover data. With newly prepared land cover dataset for the Doam-dam watershed, the SWAT model better predicts hydrologic and sediment behaviors. The number of HRUs with new land cover data increased by 70.2% compared with that with the MOE land cover, indicating better representation of small-sized agricultural field boundaries. The SWAT estimated annual average sediment yield with the MOE land cover data was 61.8 ton/ha/year for the Doam-dam watershed, while 36.2 ton/ha/year (70.7% difference) of annual sediment yield with new land cover data. Especially the most significant difference in estimated sediment yield was 548.0% for the subwatershed #2 (165.9 ton/ha/year with the MOE land cover data and 25.6 ton/ha/year with new land cover data developed in this study). The results obtained in this study implies that the use of MOE land cover data in SWAT sediment simulation for the Doam-dam watershed could results in 70.7% differences in overall sediment estimation and incorrect identification of sediment hot spot areas (such as subwatershed #2) for effective sediment management. Therefore it is recommended that one needs to carefully validate land cover for the study watershed for accurate hydrologic and sediment simulation with the SWAT model.

• 한국환경복원기술학회지
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• 제25권5호
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• pp.15-27
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• 2022

Climate change is considered a severe global problem closely related to carbon storage. However, recent urbanization and land-use changes reduce carbon stocks in terrestrial ecosystems. Recently, the role of protected areas has been emphasized as a countermeasure to the climate change, and protected areas allow the area to continue to serve as a carbon sink due to legal restrictions. This study attempted to expand the scope of these protected areas to an evaluation-based environmental spatial information theme map. In this study, the area of each grade was compared, and the distribution of land cover for each grade was analyzed using the Ecological and Nature Map, Environmental Conservation Value Assessment Map and Urban Ecological Map of Sejong Special Self-Governing City. Based on this, the average carbon storage for each grade was derived using the InVEST Carbon model. As a result of the analysis, the high-grade area of the environmental spatial information generally showed a wide area of the natural area represented by the forest area, and accordingly, the carbon storage amount was evaluated to be high. However, there are differences in the purpose of production, evaluation items, and evaluation methods between each environmental spatial information, there are differences in area, land cover, and carbon storage. Through this study, environmental spatial information based on the evaluation map can be used for land use management in the carbon aspect, and it is expected that a management plan for each grade suitable for the characteristics of each environmental spatial information is required.

• Spatial Information Research
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• 제20권5호
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• pp.25-35
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• 2012

본 연구에서는 공간정보 자료원에 따른 수질특성의 영향을 비교하였다. 먼저, 비점오염부하량 평가에 영향을 미치는 토지피복별 기대평균농도(EMC)를 효과적으로 계산하기 위해, 영상분류를 통해 대청댐유역의 토지피복도를 구축하였으며, 이를 환경부 대분류 자료와 비교한 결과 88.76%의 높은 정확도를 확보하였다. 또한 토양도와 영상분류에 의한 토지피복도를 공간 중첩하여 유출곡선지수와 직접유출을 계산하였으며, 분석 결과 석천과 대청댐 유역이 가장 높게 나타났다. 그리고 직접유출과 기대평균농도를 조합하여 계산한 BOD에 대한 비점오염부하량은 삼가천합류점과 소옥천하류 유역이 높게 나타났으며, TN과 TP에 대한 비점오염부하량에서는 삼가천합류점과 봉황천하류 유역이 높게 나타났다. 영상분류에 의한 비점오염부하량의 효용성 평가를 위해 환경부 토지피복도에 의한 비점오염부하량과 상호 비교한 결과, 대청댐상류 유역에서 BOD, TN, TP에 대한 오염부하량의 오차가 각각 10.64%, 11.70%, 20.00%로 가장 크게 나타났다. 따라서 유역내 수질특성을 효과적으로 모의하기 위해서는 논과 밭이 포함된 공간정보를 활용하는 것이 비점오염부하량 평가에 바람직하다고 본다.