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A Study on the Preparation Method of Fruit Cropping Distribution Map using Satellite Images and GIS (위성영상과 GIS를 이용한 과수재배 분포도 작성 기법에 관한 연구)

  • Jo, Myung-Hee;Bu, Ki-Dong;Lee, Jung-Hyoup;Lee, Kwang-Jae
    • Journal of the Korean Association of Geographic Information Studies
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    • v.3 no.4
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    • pp.73-86
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    • 2000
  • This study focused on extracting an efficient method in the fruit cropping distribution mapping with various classification methods using multi-temporal satellite images and Geographic Information Systems(GIS). For this study, multi-temporal Landsat TM images, in observation data and existing fruit cropping area statistics were used to compare and analyze the properties of fruit cropping and seasonal distribution per classification method. As a result, this study concludes that Maximum Likelihood Method with earlier autumn satellite image was most efficient for the fruit cropping mapping using Landsat TM image. In addition, it was clarified that cropping area per administrative boundary was prepared and distribution pattern was identified efficiently using GIS spatial analysis.

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The Land Cover Changes at the Small Watersheds Using the Multi-temporal Satelite Images (다시기 위성영상을 이용한 소유역의 토지피복변화 평가)

  • Kang, Moon-Seong;Park, Seung-Woo
    • Journal of Korean Society of Rural Planning
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    • v.6 no.2 s.12
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    • pp.50-58
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    • 2000
  • The purposes of the study were to detect and evaluate the historical land use and land cover changes on the Balan watersheds from three thematic mapper (TM) data, which were taken in 1985, 1993, and 1996. The supervised and unsupervised classification methods were adopted to classify five land cover categories: Paddy, upland, forest, residential, and water. The results indicated residential areas increased significantly during the past eleven years, Forest and paddy were converted to the urban areas. Future land cover patterns were forecasted using a Markov chain method, and the simulated land coiler change ratios presented.

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Temperature Variation by Terrain Using Multitemporal TM Band 6 and DEM(With Seoul City Area) (다시기 TM 밴드 6와 DEM을 이용한 지형별 온도변화(서울시 영역을 대상으로))

  • 박민호
    • 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.

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Image Matching for Orthophotos by Using HRNet Model (HRNet 모델을 이용한 항공정사영상간 영상 매칭)

  • Seong, Seonkyeong;Choi, Jaewan
    • Korean Journal of Remote Sensing
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    • v.38 no.5_1
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    • pp.597-608
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    • 2022
  • Remotely sensed data have been used in various fields, such as disasters, agriculture, urban planning, and the military. Recently, the demand for the multitemporal dataset with the high-spatial-resolution has increased. This manuscript proposed an automatic image matching algorithm using a deep learning technique to utilize a multitemporal remotely sensed dataset. The proposed deep learning model was based on High Resolution Net (HRNet), widely used in image segmentation. In this manuscript, denseblock was added to calculate the correlation map between images effectively and to increase learning efficiency. The training of the proposed model was performed using the multitemporal orthophotos of the National Geographic Information Institute (NGII). In order to evaluate the performance of image matching using a deep learning model, a comparative evaluation was performed. As a result of the experiment, the average horizontal error of the proposed algorithm based on 80% of the image matching rate was 3 pixels. At the same time, that of the Zero Normalized Cross-Correlation (ZNCC) was 25 pixels. In particular, it was confirmed that the proposed method is effective even in mountainous and farmland areas where the image changes according to vegetation growth. Therefore, it is expected that the proposed deep learning algorithm can perform relative image registration and image matching of a multitemporal remote sensed dataset.

Analysis of Change Detection Results by UNet++ Models According to the Characteristics of Loss Function (손실함수의 특성에 따른 UNet++ 모델에 의한 변화탐지 결과 분석)

  • Jeong, Mila;Choi, Hoseong;Choi, Jaewan
    • Korean Journal of Remote Sensing
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    • v.36 no.5_2
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    • pp.929-937
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    • 2020
  • In this manuscript, the UNet++ model, which is one of the representative deep learning techniques for semantic segmentation, was used to detect changes in temporal satellite images. To analyze the learning results according to various loss functions, we evaluated the change detection results using trained UNet++ models by binary cross entropy and the Jaccard coefficient. In addition, the learning results of the deep learning model were analyzed compared to existing pixel-based change detection algorithms by using WorldView-3 images. In the experiment, it was confirmed that the performance of the deep learning model could be determined depending on the characteristics of the loss function, but it showed better results compared to the existing techniques.

The Generation of a Digital Elevatio Model in Tidal Flat Using Multitemporal Satellite Data (다시기 위성자료에 의한 조간대 수치지형모델의 작성)

  • 安忠鉉;梶原康司;建石降太郞;劉洪龍
    • Korean Journal of Remote Sensing
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    • v.8 no.2
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    • pp.131-145
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    • 1992
  • A low cost personal computer and image processing S/W were empolyed to derive Digtal Elevation Model(DEM) of tidal flat from multitemporal LANDSAT TM images, and to create three-dimensional(3D) perspective views of the tidel flat on Komso bay in west coasts of Korea. The method for generation of Digital Elevation Model(DEM) in tidal flat was considered by overlapping techniques of multitemporal LANDSAT TM images and interpolations. The boundary maps of tidal flat extracted from multitemporal images with different water high were digitally combined in x, y, z space with tide in formation and used as an inputcontour data to obtain an elevation model by interpolation using spline function. Elevation errors of less than $\pm$0.1m were achived using overlapping techniques and a spline interpolation approach, respectively. The derived DEM allows for the generation of a perspective grid and drape on the satellite image values to create a realistic terrain visualization model so that the tidal flat may be viewed from and desired direction. As the result of this study, we obtained elevation model of tidal flats which contribute to characterize of topography and monitoring of morphological evolution of tidal flats. Moreover, the modal generated here can be used for simulation of innudation according to tide and support other studies as a supplementary data set.

Unsupervised Change Detection Based on Sequential Spectral Change Vector Analysis for Updating Land Cover Map (토지피복지도 갱신을 위한 S2CVA 기반 무감독 변화탐지)

  • Park, Nyunghee;Kim, Donghak;Ahn, Jaeyoon;Choi, Jaewan;Park, Wanyong;Park, Hyunchun
    • Korean Journal of Remote Sensing
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    • v.33 no.6_2
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    • pp.1075-1087
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    • 2017
  • In this study, we tried to utilize results of the change detection analysis for satellite images as the basis for updating the land cover map. The Sequential Spectral Change Vector Analysis ($S^2CVA$) was applied to multi-temporal multispectral satellite imagery in order to extract changed areas, efficiently. Especially, we minimized the false alarm rate of unsupervised change detection due to the seasonal variation using the direction information in $S^2CVA$. The binary image, which is the result of unsupervised change detection, was integrated with the existing land cover map using the zonal statistics. And then, object-based analysis was performed to determine the changed area. In the experiment using PlanetScope data and the land cover map of the Ministry of Environment, the change areas within the existing land cover map could be detected efficiently.

Unsupervised Change Detection of KOMPSAT-3 Satellite Imagery Based on Cross-sharpened Images by Guided Filter (Guided Filter를 이용한 교차융합영상 기반 KOMPSAT-3 위성영상의 무감독변화탐지)

  • Choi, Jaewan;Park, Honglyun;Kim, Donghak;Choi, Seokkeun
    • Korean Journal of Remote Sensing
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    • v.34 no.5
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    • pp.777-786
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    • 2018
  • GF (Guided Filtering) is a representative image processing technique to effectively remove noise while preserving edge information in the digital image. In this paper, we proposed a unsupervised change detection method for the KOMPSAT-3 satellite image using the GF and evaluated its performance. In order to utilize GF for the unsupervised change detection, cross-sharpened images were generated based on GF, and CVA (Change Vector Analysis) was applied to the generated cross-sharpened images to extract the changed area in the multitemporal satellite imagery. Experimental results using KOMPSAT-3 satellite images showed that the proposed method can be effectively used to detect changed regions compared with CVA results based on existing cross-sharpened images.

Image Registration of Cloudy Pushbroom Scanner Images (구름을 포함한 푸쉬브룸 스캐너 영상의 밴드간 상호등록)

  • Lee, Won-Hee;Yu, Su-Hong;Heo, Joon
    • Korean Journal of Remote Sensing
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    • v.27 no.1
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    • pp.9-15
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    • 2011
  • Since PAN(panchromatic) and MS(multispectral) imagery of pushbroom scanner have the offset between PAN and MS CCD(charge coupled device) in the focal plane, PAN and MS images are acquired at different time and angle. Since clouds are fast moving objects, they should lead mis-registration problem with wrong matching points on clouds. The registration of cloudy imagery to recognize and remove the contamination of clouds can be categorized into three classes: (1) cloud is considered as nose and removed (2) employing multi-spectral imagery (3) using multi-temporal imagery. In this paper, method (1) and (3) are implemented and analysed with cloudy pushbroom scanner images.

A Study on the Spatial Distribution Characteristic of Urban Surface Temperature using Remotely Sensed Data and GIS (원격탐사자료와 GIS를 활용한 도시 표면온도의 공간적 분포특성에 관한 연구)

  • Jo, Myung-Hee;Lee, Kwang-Jae;Kim, Woon-Soo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.4 no.1
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    • pp.57-66
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    • 2001
  • This study used four theoretical models, such as two-point linear model, linear regression model, quadratic regression model and cubic regression model which are presented from The Ministry of Science and Technology, for extraction of urban surface temperature from Landsat TM band 6 image. Through correlation and regression analysis between result of four models and AWS(automatic weather station) observation data, this study could verify spatial distribution characteristic of urban surface temperature using GIS spatial analysis method. The result of analysis for surface temperature by landcover showed that the urban and the barren land belonged to the highest surface temperature class. And there was also -0.85 correlation in the result of correlation analysis between surface temperature and NDVI. In this result, the meteorological environmental characteristics wuld be regarded as one of the important factor in urban planning.

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