• 한국공간정보시스템학회:학술대회논문집
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• 2005.05a
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• pp.339-344
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• 2005

하이퍼스펙트럴 데이터의 효과적인 분석을 위해 밴드 추출(Feature Extraction)이나 밴드선택(Feature Selection)에 대한 연구가 최근 많이 이루어지고 있다. 본 연구는 상대적으로 많은 밴드를 가지는 하이퍼스펙트럴 영상을 식생지수(Vegetation Index)와 같은 특수한 목적에 적용하기 위해 같은 파장대의 밴드를 조합(Band Aggregation)하여 Landsat ETM+ 영상 밴드와 동일한 영상 생성을 목적으로 한다. 이를 위해 NASA에서 제공하는 밴드별 분광특성 자료를 이용하여 밴드 조합을 위한 가중치 계산식에 적용하였으며, 밴드 선택을 위한 유효 파장대를 추출해 보았다 데이터 간 편차를 줄이기 위해 실제 1분 간격으로 촬영된 동일지역의 Hyperion과 ETM+ 영상을 사용하여 알고리즘에 적용하였고, 그 결과를 영상 간 상관계수와 NDVI 영상을 이용하여 비교 분석하였다.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2006.05a
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• pp.169-174
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• 2006

도시지역의 급변하는 토지이용의 패턴 및 토지피복상태 등의 도시환경의 변화를 분석하는 것은 도시계획 및 개발계획을 기획, 입안하는데 중요한 자료로 활용될 수 있을 것이다. 본 연구에서는 구미시를 대상지역으로 하는 Landsat TM과 Landsat $ETM^+$ 인공위성 영상데이터로부터 토지피복/토지이용 분류를 수행함으로써 18년간의 광역적 도시변화를 탐지하였다. 또한 도시의 발전과 지표면 온도의 상관성을 알아보기 위하여 열적외선 파장영역을 이용하여 온도를 추출하였다. 시가지 확장으로 인한 지표면 온도의 상승을 확인하고 이를 통해 토지이용/토지피복의 상관관계 분석 및 식생지수분포를 비교하였다.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1473-1473
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• 2003

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.3
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• pp.115-123
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• 2008

Evapotranspiration mapping using both meteorological ground-based measurements and satellite-derived information has been widely studied during the last few decades and various methods have been developed for this purpose. It is significant and necessary to estimate regional evapotranspiration (ET) distribution in the hydrology and water resource research. The study focused on analyzing the surface ET of Chungbuk region using Landsat 7 ETM imagery. For this process, we estimated the regional daily evapotranspiration on May 8, 2000. The estimation of surface evapotranspiration is based on the relationship between Temperature Vegetation Dryness Index (TVDI) and Morton's actual ET. TVDI is the relational expression between Normalized Difference of Vegetation Index (NDVI) and Land Surface Temperature (LST). The distribution of NDVI corresponds well with that of land-use/land cover in Chungbuk. The LST of several part of city in Chungbuk region is higher in comparison with the averaged LST. And TVDI corresponds too well with that of land cover/land use in Chungbuk region. The low evapotranspiration availability is distinguished over the large city like Cheongju-si, Chungju-si and the difference of evapotranspiration availability on forest and paddy is high.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.359-362
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• 2004

In multi-dimensional image, ICA-based feature extraction algorithm, which is proposed in this paper, is for the purpose of detecting target feature about pixel assumed as a linear mixed spectrum sphere, which is consisted of each different type of material object (target feature and background feature) in spectrum sphere of reflectance of each pixel. Landsat ETM+ satellite image is consisted of multi-dimensional data structure and, there is target feature, which is purposed to extract and various background image is mixed. In this paper, in order to eliminate background features (tidal flat, seawater and etc) around target feature (laver farm) effectively, pixel spectrum sphere of target feature is projected onto the orthogonal spectrum sphere of background feature. The rest amount of spectrum sphere of target feature in the pixel can be presumed to remove spectrum sphere of background feature. In order to make sure the excellence of feature extraction method based on ICA, which is proposed in this paper, laver farm feature extraction from Landsat ETM+ satellite image is applied. Also, In the side of feature extraction accuracy and the noise level, which is still remaining not to remove after feature extraction, we have conducted a comparing test with traditionally most popular method, maximum-likelihood. As a consequence, the proposed method from this paper can effectively eliminate background features around mixed spectrum sphere to extract target feature. So, we found that it had excellent detection efficiency.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.11a
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• pp.793-796
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• 2004

이 논문에서 제안한 ICA기반 피처추출 알고리즘은 다차원 영상에서 각 픽셀의 반사도 분광영역이 서로 다른 물체타입(목표피처와 배경피처)으로 이루어진 선형 혼합 분광영역으로 가정되는 픽셀에 대한 목표피처 탐지를 목적으로 한다. Landsat ETM+ 위성영상은 다차원 데이터구조로 이루어져 있으며, 영상에는 추출하고자하는 목표피처와 여러 종류의 배경피처들이 혼재한다. 이 논문에서는 목표피처(김양식장) 주변의 배경피처(갯뻘, 바닷물 등)들을 효과적으로 제거하기 위하여 목표피처의 픽셀 분광영역을 배경피처의 픽셀 분광영역으로 직교투영하게 된다. 픽셀내의 나머지 목표피처 분광영역의 양은 배경피처의 분광영역을 제거함으로써 추정하게 된다. 이 논문에서 제안한 ICA기반의 피처추출 방법의 우수성을 확인하기 위하여 Landsat ETM+ 위성영상에서 김양식장 피처를 추출하는데 적용하였다. 또한 피처추출 후 제거되지 않고 남아 있는 잡음(noise)정도와 피처추출 정확도 측면에서 전통적으로 가장 많이 사용되고 있는 최대우도 분류방법과 비교실험을 하였다. 결과적으로 이 논문에서 제안하는 방법이 목표피처 주변의 혼합분광영역에서 배경피처를 효과적으로 제거하여 추출하고자 하는 목표피처를 추출하는데 있어 우수한 탐지 성능을 보임을 알 수 있었다.

• Korean Journal of Remote Sensing
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• v.18 no.3
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• pp.141-146
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• 2002

Chlorophyll-a concentration maps of Yongdam reservoir in September and October, 2001 were produced using Landsat ETM imagery and the in-situ water quality measurement data. In-situ water samples were collected on 16th September and 18th October during the satellite overpass. The correlations between the DN values of the imagery and the values of chlorophyll-a concentration were analyzed. The visible bands(band 1, 2, 3) and the near infrared band(band 4) data of September image showed the correlation coefficient values higher than 0.9. The October image showed correlation coefficient values of about 0.7 due to the low variations of chlorophyll-a concentration. Regression models between the DN values of the Landsat ETM image and the chlorophyll-a concentration have been developed for each image. The developed regression models were then applied to each image, and finally the chlorophyll-a distribution maps of Yongdam reservoir were produced. The produced maps showed the spatial distribution of the chlorophyll-a in Yongdam reservoir in a synoptic way so that the tropic state could be easily monitored and analysed in the spatial domain.

• Journal of the Korean Regional Science Association
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• v.31 no.3
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• pp.99-112
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• 2015

Observation of land surface temperature in industrial areas is problematic, as it is not possible to construct a network of weather stations with sufficiently high density and continuous operation in such zones. Multiphase remote sensing data that cover a wide area and take a short time to process can enable the user to precisely and continuously measure the current and changing land surface temperatures in a certain region. Jeollanam-Do in South Korea is undergoing rapid industrialization, with the establishment of a number of industrial complexes, such as the Gwangyang Steelworks, Yeosu Industrial Complex, Yulchon Industrial complex, and Daebul Industrial Complex. To look into the properties of industrial complex's temperature, this study uses the thermal band of Landsat 7 ETM+ images acquired under thermal infrared wavelengths in order to calculate and compare the surface temperatures of the four above-named industrial complexes. From this, it is possible to obtain the basic information about industrial complex for environmental and natural resource management, which will aid industrial complex planners in developing methods of addressing environmental problems.

• Korean Journal of Remote Sensing
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• v.19 no.2
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• pp.117-133
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• 2003

A field survey and Landsat ETM+ image acquisition carried out simultaneously. Using these data, we attempted to establish relationships between tidal flat environmental factors and reflectance observed by ETM+, and to set up a new critical grain size useful for optical remote sensing. Although the grain size of 4 $\Phi$ has been conventionally used as a critical size by sedimentologists, the correlation with optical reflectance was very low. Instead, the grain size of 2 $\Phi$ showed a relatively high correlation coefficient, 0.699, with ETM+ band 4, except near tidal channels in upper tidal flat. We concluded that the grain size of 2 $\Phi$ would be better to use for a critical grain size in Gomso Bay. The grain size also correlated well with moisture content having a correlation coefficient of -0.811 when the 2 $\Phi$ criterion was used. The results of factor analysis showed moisture content was more important parameter than topographic relief, and they were different from German tidal flats in which topographic relief was the prior factor This can be explained by finer grain composition of the Gomso bay tidal flat. In short, moisture content and topography as well as grain size should be considered in tidal flat remote sensing.

• Journal of Korean Society for Geospatial Information Science
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• v.19 no.2
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• pp.55-61
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• 2011

The land use has been changed artificially and caused the result of temperature increase of city compared with the outside of city or region of park and forest. The purpose of this research is to analyze the change of the urban surface temperature with land use zoning in Jinju using Landsat TM/$ETM^+$ imagery and to provide the correlation between NDVI(Normalized Difference Vegetation Index) and urban surface temperature change. The results presented that the spatial distribution of urban surface temperature was depending on the change of NDVI values on land use zoning. Considering to the average temperature by land use zoning, industrial area was the highest temperature but green area was the lowest temperature. Also as a result of comparing the correlation between surface temperature and NDVI, the green and residential area had higher correlation values than the commercial and industrial area. These results will be played a part as one of the major factors for implementing the sustainable urban planning considering the urban heat island effect problem.