• Title/Summary/Keyword: Landsat imagery

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Delineation Of Coastal Features And Relative Turbidity Levels In The Mid West Sea Of Korea Using Landsat Imagery

  • Youn, Oong Koo;Lee, Byung Don;Kwak, Hi-Sang
    • 한국해양학회지
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    • v.11 no.1
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    • pp.9-17
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    • 1976
  • Multispectral scanner data collected by LANDSAT-1 over the mid West Sea of Korea were analyzed and interpreted for delineation of coastal features and turbidity distribution patterns during different portions of the tidal cycle. Imagery from two successful LANDSAT-1 overpasses of the area in October 1972 and in October 1973 had been used to prepare schematic maps of coastal features and turbidity distributions. Color composite imagery of LANDSAT MSS 4, 5 and 7 gave the best representation of shorelines, coastlines and tidal flats. MSS 5 imagery was most effective in differentiating relative turbidity levels through density slicing techniques. Referring to the tidal power development of Garolim Bay, the basin area measurements assuming dyke construction at the bay entrance, have been carried out on the coastal reature maps comiled from LANDSAT imagery, and those results were correlated with existing data. General areal patterns of surface turbidity distribution in the study area revealed close similarity with bathymetry of the area. Synoptic circulation patterns were also well discriminated from the LANDSAT imagery using the suspended sediment as a tracer.

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Applications of Landsat Imagery and Digital Terrain Model Data to River Basin Analyses (Landsat 영상과 DTM 자료의 하천유역 해석에의 응용기법 개발)

  • 조성익;박경윤;최규홍;최원식
    • Korean Journal of Remote Sensing
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    • v.2 no.2
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    • pp.117-131
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    • 1986
  • The purpose of this study was to develop techniques acquiring hydrologic parameters that affect runoff conditions from Landsat imagery. Runoff conditions in a study area were analyzed by employing the U.S. Soil Conservation Service(SCS) Method. SCS runoff curve numbers(CN) were estimated by the computer analysis of Landsat imagery and digiral terrain model(DTM) data. The SCS Method requires land use/cover and soil conditions of the area as input parameters. A land use/cover map of 5 hydrological classes was produced from the Landsat multi-spectral scannerr imagery. Slope-gradient and contour and contour maps were also made using the DTM topographic data. Inundation areas depending on reservoir levels were able to be mapped on the Landsat scene by combining the contour data.

Downscaling of MODIS Land Surface Temperature to LANDSAT Scale Using Multi-layer Perceptron

  • Choe, Yu-Jeong;Yom, Jae-Hong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.35 no.4
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    • pp.313-318
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    • 2017
  • Land surface temperature is essential for monitoring abnormal climate phenomena such as UHI (Urban Heat Islands), and for modeling weather patterns. However, the quality of surface temperature obtained from the optical space imagery is affected by many factors such as, revisit period of the satellite, instance of capture, spatial resolution, and cloud coverage. Landsat 8 imagery, often used to obtain surface temperatures, has a high resolution of 30 meters (100 meters rearranged to 30 meters) and a revisit frequency of 16 days. On the contrary, MODIS imagery can be acquired daily with a spatial resolution of about 1 kilometer. Many past attempts have been made using both Landsat and MODIS imagery to complement each other to produce an imagery of improved temporal and spatial resolution. This paper applied machine learning methods and performed downscaling which can obtain daily based land surface temperature imagery of 30 meters.

Land Cover Change Detection in the Nakdong River Basin Using LiDAR Data and Multi-Temporal Landsat Imagery (LiDAR DEM과 다중시기에 촬영된 Landsat 영상을 이용한 낙동강 유역 내 토지피복 변화 탐지)

  • CHOUNG, Yun-Jae
    • Journal of the Korean Association of Geographic Information Studies
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    • v.18 no.2
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    • pp.135-148
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    • 2015
  • This research is carried out for the land cover change detection in the Nakdong River basin before and after the 4 major rivers restoration project using the LiDAR DEM(Digital Elevation Model) and the multi-temporal Landsat imagery. Firstly the river basin polygon is generated by using the levee boundaries extracted from the LiDAR DEM, and the four river basin imagery are generated from the multi-temporal Landsat-5 TM(Thematic Mapper) and Landsat-8 OLI(Operational Land Imager) imagery by using the generated river basin polygon. Then the main land covers such as river, grass and bare soil are separately generated from the generated river basin imagery by using the image classification method, and the ratio of each land cover in the entire area is calculated. The calculated land cover changes show that the areas of grass and bare soil in the entire area have been significantly changed because of the seasonal change, while the area of the river has been significantly increased because of the increase of the water storage. This paper contributes to proposing an efficient methodology for the land cover change detection in the Nakdong River basin using the LiDAR DEM and the multi-temporal satellite imagery taken before and after the 4 major rivers restoration project.

An Quantitative Analysis of Severity Classification and Burn Severity At the targe-fire Areas Using NBR Index of Landsat Imagery (Landsat NBR지수를 이용한 대형산불 피해지 구분 및 피해강도의 정량적 분석)

  • Won, Myoung-Soo;Koo, Kyo-Sang;Lee, Myung-Bo
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.231-237
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    • 2007
  • To monitor process of vegetation rehabilitation at the damaged area after large-fire is required a lot of manpowers and budgets. However the analysis of vegetation recovery using satellite imagery can be obtaining rapid and objective result remotely in the large damaged area. Space and airbone sensors have been used to map area burned, assess characteristics of active fires, and characterize post-fire ecological effects. Burn severity incorporates both short- and long-term post-fire effects on the local and regional environment. Burn severity is defined by the degree to which an ecosystem has changed owing to the fire. To classify fire damaged area and analyze burn severity of Samcheok fire area occurred in 2000, Cheongyang fire 2002, and Yangyang fire 2005 was utilized Landsat TM and ETM+ imagery. Therefore the objective of the present paper is to quantitatively classify fire damaged area and analyze burn severity using normalized burn index(NBR) of pre- and post-fire's Landsat satellite imagery.

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Detection of Small Shallow-water Coral Reefs on Landsat Imagery

  • Trisirisatayawong, Itthi;Samanloh, Watcharee
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.479-481
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    • 2003
  • Large number of coral reefs in Thailand waters make the use of satellite imagery probably the only practical method for their monitoring. This paper reports the result of detecting small shallow-water coral reef by using maximum likelihood classification technique. Combination of blue/green and near-infrared band ratio are used as spectral signatures derived from a Landsat 7 imagery covering western portion of the Gulf of Thailand. Result assessment reveals accuracy significantly over 60 percent. The result is encouraging and would be a basis for further study to realize the full potential and limitation of this technique.

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Fire-Induced Forest Disturbance Mapping by Using QuickBird Imagery (QuickBird 화상을 이용한 산불 삼림교란도 작성)

  • Kim, Choen
    • Korean Journal of Remote Sensing
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    • v.25 no.1
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    • pp.85-94
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    • 2009
  • This paper presents the capability to use QuickBird imagery for effects of forest disturbance in Okgye burned area. Particular attention of this paper deals with the NBR-derived mapping burn severity on QuickBird imagery to locate reliable rehabilitation(namely, secondary succession) over postfire surface. Comparisons of the mapping forest disturbance derived from QuickBird NBR data and the mapping burn severity derived from Landsat ${\Delta}NBR$ data show substantial agreement (KHAT value =0.7886). The method calculated from the correlation between QuickBird wetness and Landsat ETM+ band7 may have application to forest harvest disturbance.

The Analysis of Sea Surface Temperature Distribution Using Atmospheric Corrected Landsat Imagery (대기보정된 Landsat 위성영상을 이용한 해수온도 분석)

  • Kim, Gi-Hong;Hong, Sung-Chang;Youn, Jun-Hee
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.26 no.3
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    • pp.219-225
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    • 2008
  • There are many problems in monitering environmental change around of nuclear power station, because interesting area is coastal and relatively large. The ground resolution of Landsat ETM+ imagery is high (30 m), but this imagery does not have enough informations for conducting atmospheric correction in evaluating sea surface temperatures. On the other hand, while it is possible to conduct atmospheric correction using MODIS imagery with it's two infrared bands, it's resolution is relatively low (1 km). Therefore, atmospheric corrected high resolution temperature information can be obtained from these two satellite images. In this study, digital numbers of Landsat ETM+ data in interesting area are georeferenced, converted to effective temperatures based on radiance value, and then the atmospheric correction is conducted using MODIS data. As a result, about $3.5^{\circ}C$ temperature differences were detected in comparing sea surface temperature of the surrounding area of Uljin nuclear power station with it of the same area located 5km far east.

Detection of Urban Expansion and Surface Temperature Change using Landsat Satellite Imagery (Landsat 위성영상을 이용한 도시확장 및 지표온도 변화 탐지)

  • Song, Yeong-Sun
    • Journal of Korean Society for Geospatial Information Science
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    • v.13 no.4 s.34
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    • pp.59-65
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    • 2005
  • It is very important to detect land cover/land use change from the past and to use it for future urban plan. This paper investigated the application of Landsat satellite imagery for detecting urban growth and assessing its impact on surface temperature in the region. Land cover/land use change detection was carried out by using 30m resolution Landsat satellite images and hierarchial approach was introduced to detect more detail change on the changing area through high resolution aerial photos. Also, surface temperature according to land cover/land use was calculated from Landsat TM thermal infrared data and compared with real temperature to analyze the relationship between urban expansion and surface temperature. As a result, the urban expansion has raised surface radiant temperature in the urbanized area. The method using remote sensing data based on GIS was found to be effective in monitoring and analysing urban growth and in evaluating urbanization impact on surface temperature.

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