• 제목/요약/키워드: Landsat 영상

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Analysis of Thermal Heat Island Potential by Urbanization Using Landsat-8 Time-series Satellite Imagery (Landsat-8 시계열 위성영상을 활용한 도심지 확장에 따른 열섬포텐셜 분석)

  • Kim, Taeheon;Lee, Won Hee;Han, Youkyung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.4
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    • pp.305-316
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    • 2018
  • As the urbanization ratio increases, the heat environment in cities is becoming more important due to the urban heat island. In this study, the heat island spatial analysis was calculated and conducted for analysis of urban thermal environment of Sejong city, which was launched in 2012 and has been developed rapidly. To analyze the ratio and change rate of urban area, a multi temporal land cover map (2013 to 2015 and 2017) of study area is generated based on Landsat-8 OLI/TIRS (Operational Land Imager / Thermal Infrared Sensor) satellite imagery. Then, we select an TIR (Thermal Infrared) band from the two TIR bands provided by the Landsat-8, which is used for calculating the heat island potential, through the accuracy evaluation of the brightness temperature and AWS (Automatic Weathering Station) data. Based on the selected band and surface emissivity, land surface temperature is calculated and the estimated heat island potential change is analyzed. As a result, the land surface temperature of the high ratio and change rate of urban area was significantly higher than the surrounding area around $3^{\circ}C$ to $4^{\circ}C$, and the heat island potential was also higher around $4^{\circ}C$ to $5^{\circ}C$. However, the heat island phenomenon was alleviated in urban areas with high rate of change that also show high green area ratio. Therefore, we demonstrated that dense urban area increases the possibility of inducing heat island, but it can mitigate the heat island through green areas.

A Study on Rice Growth and Yield Monitoring Using Medium Resolution Landsat Imagery (LANDSAT 위성영상을 이용한 벼 생육 및 수량 모니터링)

  • Kim, Min-Ho;Lee, Chung-Kuen;Park, Ho-Ki;Lee, Jae-Eun;Koo, Bon-Cheol;Shin, Jin-Chul
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.53 no.4
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    • pp.388-393
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    • 2008
  • Earth observation satellite imagery having medium-resolution can provide the useful information very rapidly and cheaply. The objective of this study was to assess the feasibility for monitoring rice growth and yield using medium resolution satellite imagery at Seosan AB reclaimed area, Chung-nam province. Using the LANDSAT imagery at booting stage ($29^{th}$ July 2004), $NDVI_R$ had the most significant linear relationships with rice yield of Seosan AB reclaimed area with the correlation coefficient (r) as 0.68. Therefore, this relationship was established as rice yield equation as function of $NDVI_R$, where excluding the 10 small area having low number of pixel, the determination coefficient ($R^2$) of the linear regression between NDVIred and milled rice yield was improved to 0.66. In addition, raster masking method, which was easier and faster even if a little unaccurate than preexisting method, was established for extracting information paddy field zone. Adaptability of rice yield equation function of $NDVI_R$ on year and region was investigated using rice yield and $NDVI_R$ values, which were extracted with raster masking method, from 7 counties or cities, Kyeong-ki province in 2005. Relationship between observed and calculated rice yield showed 1:1 line indicating that the adaptability was admitted.

A Study on Mitigation Plan of Urban Heat Island Phenomenon Using Landsat Time Series Imagery - Focusing on Cheongna International City - (시계열 Landsat 위성영상을 활용한 도시 열섬 현상 완화 방안에 관한 연구 - 청라 국제도시를 중심으로 -)

  • BAEK, Seon-Uk;KIM, Dong-Hyun;KIM, Hung-Soo;GU, Bon-Yup;CHOUNG, Yun-Jae
    • Journal of the Korean Association of Geographic Information Studies
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    • v.25 no.3
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    • pp.1-16
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    • 2022
  • Areas developed through land reclamation projects have huge economic advantages in terms of supplying lands that can be used for farmlands, urban areas and etc., however have relatively small areas of grasslands and densely located buildings compared to inland cities. Hence, an urban heat island is occurring in these areas due to this characteristic, and in particular, the urban heat island in Cheongna International City is getting serious. In this study, the urban heat island in Cheongna International City was evaluated and analyzed by classified into the three periods after the reclamation project: farmland(2001-2008), development(2009-2013) and artificial grassland(2014-2020). The land cover map and Landsat time-series imagery were utilized for measuring the differences of the land surface temperatures between the urbanized areas and the grassland/forest areas in Cheongna International City. The statistical results showed that the differences in the land surface temperature between these areas were calculated to be at most 0℃ during the period of farmland, at most 3.60℃ during the period of development, and at most 2.51℃ during the period of grassland. This study proved that the urban heat island phenomenon increased when the urbanized areas increased, and the urban heat island phenomenon decreased when the artificial grassland areas increased in Cheongna International City where the reclamation project was carried out. The statistical results derived through this research can be used as the reference data for identifying the urban heat island problem in urban planning and establishing the reduction plan.

The Validation of Landsat TM Band Ratio Algorithm using In-water Optical Measurement (수중 광학측정을 이용한 Landsat TM 밴드비율 알고리듬 검증)

  • Jeong, Jong-Chul
    • Journal of the Korean Association of Geographic Information Studies
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    • v.4 no.1
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    • pp.18-26
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    • 2001
  • Landsat TM band ratio algorithms were made by in-water optical measurement data of each sampling points for water quality monitoring of coastal area using Landsat TM satellite data. The algorithm was derived from in-water optical reflectance data which was measuring by the PRR(profiling reflectance radiometer). And, in-water optical reflectance data were applied to Landsat TM bands. Relationship between in-water optical reflectance and pigments proposed by the ratio of TM band 1 and band 2 showed to as follows; $Y=3.8352{\times}(R(band\;1)/R(band\;2))^{-2.1978}$ ($R^2$=0.7069) and, relationship of the ratio of TM band 1 and band 3 as follows; $Y=23.288{\times}(R(band\;1)/R(band\;3))^{-1.5243}$ ($R^2$=0.8062). Calculated the upwelling radiance of water surface and radiance of TM showed the ratio of atmospheric effect. In the coastal area Rayleigh and Mie scattering of atmosphere is to make over 80% of normalized radiance of Landsat TM. In order to apply in-water algorithm obtained by PRR, we had to calculate the atmospheric effects at sampling site. And, the quantitative analysis of in-water components using Landsat TM data need the calibration of in-water algorithm and effective method of atmospheric correction.

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Estimating the Variations of Tidal Flat Areas after the Seawall Construction from Topographic Maps, Hydrographic Charts, and Satellite Images (지형도, 해도 및 위성영상을 이용한 방조제 축조 후의 간석지 면적 변화 추정)

  • Gang, Mun-Seong;Park, Seung-U;Kim, Sang-Min
    • Journal of Korea Water Resources Association
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    • v.34 no.6
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    • pp.597-604
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    • 2001
  • The objective of the paper was to estimate the changes in acreages of tidal flats after the seawall construction at the Asan Bay and the Chunsu Bay from topographic maps, hydrographic charts, and Landsat TM images. The tidal floats from topographic maps published in one year differ significantly from that in the other, which appears to be attributed to the tide levels at the time of photographing. The hydrographic charts showed that tidal flats increase at rates of 22.3 ha/yr at the Asan Bay and 56.6 ha/yr at the Chunsu Bay after the dike construction. Applying the ISODATA method of unsupervised classifications for the Landsat TM images, the tidal flats were identified, and the resulting acreages for each image estimated. The resulting tidal flats increased at the rates of 21.3 ha/yr at the Asan Bay and 47.3 ha/yr at the Chunsu Bay during twelve years after the dike construction. It was found that the rates of the annual increases from the two data are very close and the differences result from the coastal lines at the charts and the TM images.

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A Selection of Atmospheric Correction Methods for Water Quality Factors Extraction from Landsat TM Image (Landsat TM 영상으로부터 수질인자 추출을 위한 대기 보정 방법의 선정)

  • Yang, In-Tae;Kim, Eung-Nam;Choi, Youn-Kwan;Kim, Uk-Nam
    • Journal of Korean Society for Geospatial Information Science
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    • v.7 no.2 s.14
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    • pp.101-110
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    • 1999
  • Recently, there are a lot of studies to use a satellite image data in order to investigate a simultaneous change of a wide range area as a lake. However, in many cases of the water quality research there is one problem occured when extracting the water quality factors from the satellite image data because the atmosphere scattering exert a bad influence on a result of analysis. In this study, an attempt was made to select the relative atmospheric correction method, extract the water quality factors from the satellite image data. And also, the time-series analysis of the water quality factors was performed by using the multi-temporal image data.

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A Change Detection of Western Coastal Land-Use using Landsat TM Images (Landsat TM 영상을 이용한 서해안 토지이용의 변화 추적)

  • 양인태;박재국;김흥규
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.17 no.4
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    • pp.411-420
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    • 1999
  • Coastal development and reclamation work make environment of shore destroy, such as rapid change of land use and destruction of wet-land and ocean ecosystem. Therefore new technique to detect change have been needed. This study designed new change detection method and applied to study area. The change detection image and quantitative change area by each classes are calculated. Also, this study can use the basic idea-determination data for coastal development and city plan as the sense of sight by changed images that changed from any land-cover to any land-cover between two dates.

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Standardizing Agriculture-related Land Cover Classification Scheme using IKONOS Satellite Imagery (IKONOS 영상자료를 이용한 농업지역 토지피복 분류기준 설정)

  • Hong Seong-Min;Jung In-Kyun;Kim Seong-Joon
    • Korean Journal of Remote Sensing
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    • v.20 no.4
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    • pp.253-259
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    • 2004
  • The purpose of this study is to present a standardized scheme for providing agriculture-related information at various spatial resolutions of satellite images including Landsat + ETM, KOMPSAT-1 EOC, ASTER VNIR, and IKONOS panchromatic and multi-spectral images. The satellite images were interpreted especially for identifying agricultural areas, crop types, agricultural facilities and structures. The results were compared with the land cover/land use classification system suggested by National Geographic Information based on aerial photograph and Ministry of Environment based on satellite remote sensing data. As a result, high-resolution agricultural land cover map from IKONOS imageries was made out. The classification result by IKONOS image will be provided to KOMPSAT-2 project for agricultural application.

Neural Network Based Land Cover Classification Technique of Satellite Image for Pollutant Load Estimation (신경망 기반의 오염부하량 산정을 위한 위성영상 토지피복 분류기법)

  • Park, Sang-Young;Ha, Sung-Ryong
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2001.12a
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    • pp.1-4
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    • 2001
  • The classification performance of Artificial Neural Network (ANN) and RBF-NN was compared for Landsat TM image. The RBF-NN was validated for three unique landuse types (e.g. Mixed landuse area, Cultivated area, Urban area), different input band combinations and classification class. The bootstrap resampling technique was employed to estimate the confidence intervals and distribution for unit load, The pollutant generation was varied significantly according to the classification accuracy and percentile unit load applied. Especially in urban area, where mixed landuse is dominant, the difference of estimated pollutant load is largely varied.

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Vegetation Change Detection in the Sihwa Embankment using Multi-Temporal Satellite Data (다중시기 위성영상을 이용한 시화 방조제 내만 식생변화탐지)

  • Jeong, Jong-Chul;Suh, Young-Sang;Kim, Sang-Wook
    • Journal of Environmental Science International
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    • v.15 no.4
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    • pp.373-378
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    • 2006
  • The western coast of South Korea is famous for its large and broad tidal lands. Nevertheless, land reclamation, which has been conducted on a large scale, such as Sihwa embankment construction project has accelerated coastal environmental changes in the embankment inland. For monitoring of environmental change, vegetation change detecting of the embankment inland were carried out and field survey data compared with Landsat TM, ETM+, IKONOS, and EOC satellite remotely sensed data. In order to utilize multi-temporal remotely sensed images effectively, all data set with pixel size were analyzed by same geometric correction method. To detect the tidal land vegetation change, the spectral characteristics and spatial resolution of Landsat TM and ETM+ images were analyzed by SMA(spectral mixture analysis). We obtained the 78.96% classification accuracy and Kappa index 0.2376 using March 2000 Landsat data. The SMA(spectral mixture analysis) results were considered with comparing of vegetation seasonal change detection method.