• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.75-78
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• 2003

This study is to present a method of land cover change detection by the typhoon RUSA (August 1 - September 4, 2002) using Landsat 7 ETM+ images. For the Namdae-cheon watershed in Gangreung, two images of Sept. 29, 2000 and Nov. 22, 2002 were prepared. To identify the damaged areas, firstly, the NDVI (Normalized Difference Vegetation Index) of each image was computed, secondly, the NDVI values were reclassified as two categories that the negative index values including zero are the one and the positive index values are the other, thirdly the reclassified image before typhoon is subtracted from the reclassified image after typhoon to get DNDVI (Differential NDVI). From the DNDVI image, the flooded and damaged areas could be extracted.

• Proceedings of the IEEK Conference
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• 2003.07e
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• pp.2343-2346
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• 2003

The spatial resolution of multispectral images can be improved by merging them with higher resolution image data. A fundamental problem frequently occurred in existing fusion processes, is the distortion of spectral information. This paper presents a spatially adaptive image fusion algorithm which produces visually natural images and retains the quality of local spectral information as well. High frequency information of the high resolution image to be inserted to the resampled multispectral images is controlled by adaptive gains to incorporate the difference of local spectral characteristics between the high and the low resolution images into the fusion. Each gain is estimated to minimize the l$_2$-norm of the error between the original and the estimated pixel values defined in a spatially adaptive window of which the weight are proportional to the spectral correlation measurements of the corresponding regions. This method is applied to a set of co-registered Landsat7 ETM＋ panchromatic and multispectral image data.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.153-157
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• 2004

본 인구는 돌발홍수 예경보시스템의 수문학적 주요 구성요소인 한계유출량을 한강유역에 내해 산정하는 것이 주목적이다. 이를 위해 Landsat TM 영상자료로 추출된 DEM 자료로부터 미소 소유역($0.01\~56.7km^2$) 및 하천도를 추출하고, 자연하도 및 소유역 매개변수의 지역적 회귀분석을 통해 Manning의 제방월류 유량($Q_{bf}$) 및 GIUH의 단위도 첨두유량($q_{pR}$)을 계산하였다. 이러한 결과를 활용하여 한강유역 headwater 유역에 대한 1시간 단위의 한계유출량을 계산한 결과, 그 값이 $0.01\~1.29inch(0.25\~32.77mm)$의 범위를 보였으며, 상류쪽 유역이고 유역면적이 작은 소유역일수록 한계유출량이 작게 산정되었다.

• Economic and Environmental Geology
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• v.30 no.3
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• pp.241-248
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• 1997

In this study, Ichon basin is selected as study area and regional analysis of geological structure are done by using lineament analysis. The factors which affects slope stability, are chosen, and integrated to database using GIS (Geoscientific Information System). Landsat TM band 4, 5 and 7 are choosen and processed by various image enhancement technique to analyse the regional geological lineaments. Spatial distribution of lineament is analysed through lineament density map and study area can be divided the eight structural domains. Considering environmental geological characteristics of study area, rating and weighting of each factors for slope stability analysis are determined and spatial analysis of regional slope stability is examined through overlaying technique of GIS. The result of areal distribution of slope stability shows that the most unstable area is all over Mt. Buksung, Mt. Daepo, Mt. Songrim and Mt. Yankak.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.203-210
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• 2004

The average temperatures by the land cover class, by the elevation extent, by the slope and by the aspect have been calculated using multitemporal Landsat TM band 6 and DEM. For this, the TM band 6 data from October 21, 1985, June 2, 1992, September 1, 1996, May 7, 2000 and the 28.5m x 28.5m grid elevation data of Seoul have been used. From the varying curve of the average land surface temperature by the elevation extent, the presence of the atmospheric inversion phenomenon and the scope of the inversion layer can be inferred. Especially, the average land surface temperature by the aspect can be effective for deciding a road line. For these reasons, it is expected that temperature estimation using remote sensing data shall be effective for the survey of heat damage, environmental temperature monitoring, and urban and environmental Planning usage.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.03a
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• pp.215-220
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• 2004

유역수문모형에서 SCS방법 적용시 입력되는 주요 매개변수인 유역평균 CN값은 RS와 GIS를 적용하면 쉽게 계산이 가능하나, 입력자료의 종류 및 공간해상도의 선택에 따라 같은 자료일 지라도 다르게 계산된다. 본 연구에서는 Landsat 7 ETM+,SPOT 5, 1:25,000 토지이용현황도, 정밀토양도, 개략토양도를 이용하여 2.5m, 30m 공간해상토의 자료로부터 유역평균CN을 계산하였으며, 이들을 각각 2.5m～1000m 크기의 격자로 재배열하여 유역평균을 비교함으로서 해상도가 유역 CN값 변화와 어떠한 관계가 있는지 분석하고자 하였다. 분석결과 해상도에 따라 일정구간 이상에 대하여 오차를 나타내고 있었으며, 자료의 선택에 따라 유역평균 CN 값의 변화가 있는 것으로 분석되었다.

• Proceedings of the KSRS Conference
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• 2009.03a
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• pp.309-313
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• 2009

산불은 전세계적으로 발생하는 가장 주요한 재해현상 중 하나이다. 산불 감시나 산불에 의한 피해지역의 효과적인 관측은 피해 지역을 최소화하고, 효율적인 피해 복구 계획 수립에 매우 중요한 기초자료를 제공한다. 광학 위성 자료를 활용한 산불 피해지역 탐지가 널리 사용되고 있음에도 불구하고, 산불에 의한 연기 또는 구름 분포에 의해 종종 사용상에 제약이 있다. 본 연구에서는 2000년 4월 강원도 고성, 강릉, 삼척, 물진 지역에서 발생한 대규모 산불을 연구 대상지역으로 하여, 1998년-2000년 동안 획득된 RADARSAT-1 SAR 영상을 이용하여 산불 피해 지역 감시의 활용성을 연구하였다. 산불에 의한 산림 피해지역 관측을 위해 RADARSAT-1 SAR 영상의 후방산란관의 변화를 통한 변환 탐지를 수행하였다. 산불 피해지역에서 산불 전에 비해 산불 후에 획득된 RADARSAT-1 SAR 영상의 후방산란값이 증가하는 것으로 관측되었다. RADARSAT-1 SAR 영상으로부터 관측된 산불 피해 지역은 Landsat-7 ETM 자료와 현장 조사 자료에 의한 산불 피해 지역과 매우 상관성이 높은 것으로 관측되었다.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.274-274
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• 2002

Damage to forest trees, caused by wildfire, changes their spectral reflectance signature. This factor led to the initiation of a research project at the Remote Sensing & GIS Laboratory, Kookmin University, to determine if multispectral data acquired by IKONOS could provide fire scar and bum severity mapping. This paper will present detail mapping of burned areas in the eastern coast of Korea with IKONOS imagery. In addition, a single post-burn Landsat-7 ETM＋ data was used to compare with IKONOS, the study area. Burn severity map based on IKONOS image was found to be affected by strong topographic illumination effects in the mountain forest. But it has better the delineation of the bum-scarred area. In this study the NDVI was analyzed for geometric illumination conditions influenced by topography(slop, aspect and elevation) and shadow(solar elevation and azimuth angle).

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.96-99
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• 2003

Land cover map is a typical GIS database which shows the Earth's physical surface differentiated by standardized homogeneous land cover types. Satellite images acquired by Landsat TM were primarily used to produce a land cover map of 7 land cover classes; however, it now becomes to produce a more accurate land cover classification dataset of 23 classes thanks to higher resolution satellite images, such as SPOT-5 and IKONOS. The use of the newly produced high resolution land cover map of 23 classes for such activities to estimate non-point sources of pollution like water pollution modeling and atmospheric dispersion modeling is expected to result a higher level of accuracy and validity in various environmental monitoring results. The estimation of pollution from non-point sources using GIS-based modeling with land cover dataset shows fairly accurate and consistent results.

• Korean Journal of Remote Sensing
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• v.19 no.5
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• pp.371-380
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• 2003

The primary objective of this study is to develop a suitable methodology to generate forest leaf area index (LAI) map at regional and local scales. To build empirical models, we collected the LAI values at 30 sample plots over the forest within the kyongan watershed area by the field measurements using an optical instrument. Landsat-7 ETM＋ multispectral data obtained at the same growing season with the field LAI measurement were used. Three datasets of remote sensing signal were prepared for analyzing the relationship with the field measured LAI value and they include raw DN, atmospherically corrected reflectance, and topographically corrected reflectance. From the correlation analysis and regression model development, we found that the radiometric correction of topographic effects was very critical step to increase the sensitivity of the multispectral reflectance to LAI. In addition, the empirical model to generate forest LAI map should be separately developed for each of coniferous and deciduous forest.