• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.159-159
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• 2017

효율적인 물 관리를 위해서는 하천 유량 파악이 필수적이지만, 경제적 이유 등으로 인하여 현장에서 정확한 유량 자료를 꾸준히 확보하는 데에는 한계가 있다. 본 연구에서는 이러한 문제점을 극복하고자 SAR 영상을 이용하여 하천의 수위와 유량을 추정하였다. SAR 영상 자료는 악천후 및 주야의 영향을 받지 않는 ESA(European Space Agency)의 Sentinel-1 영상을 이용하였다. 위성자료에서 하천의 면적을 추출한 후 수위 및 유량과의 상관관계를 분석하였다. 촬영 시간 등에 의한 위성 영상의 조도 차이에 따른 하천 면적의 오차를 제거하기 위하여 영상을 보정하였고 주변 지역에 의한 오차를 줄이기 위하여 하천유역을 분리하여 면적을 추출하였다. 이를 통해 하천 면적과 수위 및 유량의 상관관계를 파악하였다. 국내 10여 개의 하천에 대하여 기법을 적용한 결과, 수위와 유량을 비교적 정확히 추정할 수 있었다. 본 연구의 결과는 미계측 유역의 수자원 관리 능력을 향상시킬 것으로 기대된다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.22 no.1
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• pp.81-90
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• 2004

Because satellite images include geometry distortions according to photographing conditions and sensor property, and their spatial and radiational resolution and spectrum resolution are different, it is so difficult to make a precise results of analysis. For comparing more than two images, the precise geometric corrections should be preceded because it necessary to eliminate systematic errors due to basic sensor information difference and non-systematic errors due to topographical undulations. In this study, we did sensor modeling using satellite sensor information to make a basic map of change detection for artificial topography. We eliminated the systematic errors which can be occurred in photographing conditions using GCP and DEM data. The Kompsat EOC images relief could be reduced by precise rectification method. Classifying images which was used for change detections by city and forest zone, the accuracy of the matching results are increased by 10% and the positioning accuracies also increased. The result of change detection using basic map could be used for basic data fur GIS application and topographical renovation.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.3
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• pp.168-175
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• 2006

The cultural grounds of lave r have been surveyed using SPOT-5 satellite images. The facilities of laver cultivation area in the coastal waters of Korea were calculated. 10 m resolution multispectral images of SPOT-5 are adopted for the southern are a of Jebu Island, Hwaseong city to develop an automatic detection approach of laver nets that consists of the following: band difference technique, canny edge detector and morphological analysis: The number of satellite-based facilities was relatively high as compared with the licensed number in 2005, 676,749 chaek and 572,745 chaek(柵, unit of measure for laver farm), respectively. The ratio of a law abiding facility was very low at 52.9%. These data could be applied to control its national production keeping a stable market price for the government body.

• Aerospace Engineering and Technology
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• v.7 no.2
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• pp.187-195
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• 2008

Generation of accurate ground coordinates from high resolution satellite image are becoming increasingly of interest. The primary focus of this paper is to compute satellite direct sensor model (DSM) and rational function model (RFM) for accurate generation of ground coordinates from high resolution satellite images. Being based on this we presented an algorithm to be able to efficiently ground coordinates about large area with introducing RFM(rational function model) method applied to rigorous sensor modeling standing on basis of satellite orbit dynamics and collinearity equation, and sensor modeling of high-resolution satellite data like IKONOS, QuickBird, KOMPSAT-2 and others. The general high resolution satellite measures the position, velocity and attitude data of satellite using star, gyro, and GPS sensors.

• 한국지형공간정보학회:학술대회논문집
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• 2002.11a
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• pp.117-122
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• 2002

Change detection is a useful technology that can be applied to various fields, taking temporal change information with the comparison and analysis among multi-temporal satellite images. Especially, change detection that utilizes high-resolution satellite imagery can be implemented to extract useful change information for many purposes, such as the environmental inspection, the circumstantial analysis of disaster damage, the inspection of illegal building, and the military use, which cannot be achieved by lower middle-resolution satellite imagery. However, because of the special characteristics that result from high-resolution satellite imagery, it cannot use a pixel-based method that is used for low-resolution satellite imagery. Therefore, it must be used a feature-based algorithm based on the geographical and morphological feature. This paper presents the system that builds the change map by digitizing the boundary of the changed object. In this system, we can make the change map using manual or semi-automatic digitizing through the user interface implemented with a floating window that enables to detect the sign of the change, such as the construction or dismantlement, more efficiently.

• Korean Journal of Remote Sensing
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• v.39 no.3
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• pp.339-353
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• 2023

As the availability of high-resolution satellite imagery increases, improvement of positioning accuracy of satellite images is required. The importance of orthorectified images is also increasing, which removes relief displacement and establishes true localization of man-made structures. In this paper, we performed automated extraction of building rooftops and total building areas within original satellite images using the existing building height database. We relocated the rooftop sin their true position and generated an orthorectified building layer. The extracted total building areas were used to blank out building areas and generate true orthographic non-building layer. A final orthorectified image was provided by overlapping the building layer and non-building layer.We tested the proposed method with KOMPSAT-3 and KOMPSAT-3A satellite images and verified the results by overlapping with a digital topographical map. Test results showed that orthorectified building layers were generated with a position error of 0.4m.Through the proposed method, the feasibility of automated true orthoimage generation within dense urban areas was confirmed.

• Korean Journal of Environment and Ecology
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• v.13 no.2
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• pp.153-159
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• 1999

이 논문은 북한산국립공원에서 1994년부터 실시하고 있는 자연휴식년제도의 효과를 검증하고 추후 휴식년의 적용이 필요한 구간을 파악하기 위하여 인공위성 영상자료를 이용하여 휴식년 적용구간과 그 주변 등산로의 식생활력의 변화를 분석하였다. 이용된 자료는 1988년, 1992년, 1994년, 1996년 9월의 Landsat TM 영상으로, ER Mapper 및 Arc/Info GIS를 이용하여 분석하였고, 식생활력의 측정은 중합차식생지수(NDVI)에 기반한 평균비율(MR)을 이용하였다. 분석결과 휴식년 적용구간의 경우 88년 이후 감소양상을 보이던 식생활력이 휴식년제도가 실시된 94년 이후 뚜렷하게 증가하여 휴식년제도의 실시가 식생활력을 증가시키는 효과가 있었음을 보여주었다. 기타 등산로의 경우는 92년 이후 식생활력이 정체 또는 감소추세를 나타내었으며, 그 중 일부 구간은 식생활력의 저하가 특히 두드러지게 나타나 추후 휴식년제도의 적용이 필요한 구간으로 판단되었다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.1
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• pp.19-26
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• 2003

As recently, high-resolution satellite images of 1m spatial resolution are opened to the public and able to be used commercially, the studies that make ortho-images using them and apply to digital mapping and database of geo-spatial information system are having been progressed actively. Therefore, the purposes of this study are to establish the auto-extraction methods and to develope algorithms for automatically extracting buildings out of man-made structures, after making the IKONOS ortho-image. As the result of this study, we can extract buildings automatically at 72% out of the whole buildings. And we have analyzed the error trend by means of the comparison with ortho-image, digital map and drawing result, then we could know that obtain the good result for extraction of the building through the methods and algorithms of this study.

• 한국지구물리탐사학회:학술대회논문집
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• 2004.06a
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• pp.43-47
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• 2004

• Magazine of the Korean Society of Hazard Mitigation
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• v.10 no.1
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• pp.40-43
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• 2010