• Title/Summary/Keyword: Remote sensing technique

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Unsupervised Image Classification using Region-growing Segmentation based on CN-chain

  • Lee, Sang-Hoon
    • Korean Journal of Remote Sensing
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    • v.20 no.3
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    • pp.215-225
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    • 2004
  • A multistage hierarchical clustering technique, which is an unsupervised technique, was suggested in this paper for classifying large remotely-sensed imagery. The multistage algorithm consists of two stages. The 'local' segmentor of the first stage performs region-growing segmentation by employing the hierarchical clustering procedure of CN-chain with the restriction that pixels in a cluster must be spatially contiguous. The 'global' segmentor of the second stage, which has not spatial constraints for merging, clusters the segments resulting from the previous stage, using the conventional agglomerative approach. Using simulation data, the proposed method was compared with another hierarchical clustering technique based on 'mutual closest neighbor.' The experimental results show that the new approach proposed in this study considerably increases in computational efficiency for larger images with a low number of bands. The technique was then applied to classify the land-cover types using the remotely-sensed data acquired from the Korean peninsula.

AUTOMATIC DETECTION OF OIL SPILLS WITH LEVEL SET SEGMENTATION TECHNIQUE FROM REMOTELY SENSED IMAGERY

  • Konstantinos, Karantzalos;Demetre, Argialas
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.126-129
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    • 2006
  • The marine environment is under considerable threat from intentional or accidental oil spills, ballast water discharged, dredging and infilling for coastal development, and uncontrolled sewage and industrial wastewater discharges. Monitoring spills and illegal oil discharges is an important component in ensuring compliance with marine protection legislation and general protection of the coastal environments. For the monitoring task an image processing system is needed that can efficiently perform the detection and the tracking of oil spills and in this direction a significant amount of research work has taken place mainly with the use of radar (SAR) remote sensing data. In this paper the level set image segmentation technique was tested for the detection of oil spills. Level set allow the evolving curve to change topology (break and merge) and therefore boundaries of particularly intricate shapes can be extracted. Experimental results demonstrated that the level set segmentation can be used for the efficient detection and monitoring of oil spills, since the method coped with abrupt shape’s deformations and splits.

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Research on Analytical Technique for Satellite Observstion of the Arctic Sea Ice (극지 해빙 위성관측을 위한 분석 기술 개발)

  • Kim, Hyun-cheol;Han, Hyangsun;Hyun, Chang-Uk;Chi, Junhwa;Son, Young-sun;Lee, Sungjae
    • Korean Journal of Remote Sensing
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    • v.34 no.6_2
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    • pp.1283-1298
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    • 2018
  • KOPRI(Korea Polar Research Institute) have researhed Arctic sea ice by using satellite remote sensing data since 2017 as a mission of KOPRI. The title of the reseach is "Development of Satellite Observation and Analysis for Arctc sea-ice". This project has three major aims; 1) development of prototype satellite data archive/manage system for Arctic sea ice monitoring, 2) development of sea ice remote sensing data processing and analysis technique, and 3) development of international satellite observing network for Arcitc. This reseach will give us that 1) deveolpment of sea ice observing system for northern sea route, 2) development of optimal remote sensing data processing technique for sea ice and selected satelite sensors, 3) development of international satellite onbservation network. I hope that this letter of introducton KOPRI satellite program for Arctic will help to understand Arctic remote sensing and will introduce you to step into the Arctic remote sensing, which Iis like a blue ocean of remote sensing.

Environmental Impact Assessment Using Remote Sensing Data : the Land Use Change (인공위성자료를 이용한 환경영향평가 : 토지이용 변화를 중심으로)

  • Mun, Hyun-Saing;Kim, Myung-Jin;Han, Eui-Jung;Lee, Jae-Woon;Bang, Kyu-Chul;Lee, Hee-Seon
    • Journal of Environmental Impact Assessment
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    • v.4 no.2
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    • pp.23-28
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    • 1995
  • Remote sensing begins to be applied in Environmental Impact Assessment(EIA), and it can systematically assess land use which is an important factor in EIA. This study is to predict land use change of Ulsan region and to assess impact on land use using the past and the present data of remote sensing. Also we analyzed an impact area influenced by EIA projects through the integration of remote sensing and GIS. This technique will be applied to the screening stage in EIA.

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APPLICATION OF OCEAN COLOR REMOTE SENSING IN MARINE STUDY OF VIETNAM ? STATUS AND POTENTIAL

  • Long, Bui Hong;Son, Tong Phuoc Hoang;Khin, Lau Va
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.170-173
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    • 2006
  • The remote sensing is powerful oceanographic tools not only for Integrated Coastal Zone Management (ICZM) but also for various areas of oceanography. Thank to effort of Government and local authorities as well as active support of international institutions, many projects on the applied oceanography had and have been caring out in coastal and offshore waters of Vietnam sea. One of the modern methods which has been used in these project is ocean color remote sensing technique. This paper will present some preliminary results obtain from application of these techniques in study of coastal and offshore environment of Vietnam sea.

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An initial study on ecological environment changes after emergent water transportation at lower reaches of Tarim River, China based on remote sensing technique

  • Jianli, Zhang;Lin, Li;Longjiang, Du
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.313-315
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    • 2003
  • Tarim River is the longest continental river in China. Its downstream ecological environment declination and valley remedy got great concern. To improve ecological environment of lower Tarim River, “Emergent water transportation project for Tarim river valley remedy” was carried out from May 2000. Water was transported five times till May 2003. Several periods MODIS image was used to monitor water body in river channel. Two periods ETM image was used to interpreter changes of environment. Area of vegetation in 1999 was similar with 2001, but become better in total. The normalized difference vegetation index (NDVI) and vegetative coverage reflected environment changed better.

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Estimation of Satellite-based Spatial Evapotranspiration and Validation of Fluxtower Measurements by Eddy Covariance Method (인공위성 데이터 기반의 공간 증발산 산정 및 에디 공분산 기법에 의한 플럭스 타워 자료 검증)

  • Sur, Chan-Yang;Han, Seung-Jae;Lee, Jung-Hoon;Choi, Min-Ha
    • Korean Journal of Remote Sensing
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    • v.28 no.4
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    • pp.435-448
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    • 2012
  • Evapotranspiration (ET) including evaporation from a land surface and transpiration from photosynthesis of vegetation is a sensitive hydrological factor with outer circumstances. Though both direct measurements with an evaporation pan and a lysimeter, and empirical methods using eddy covariance technique and the Bowen ratio have been widely used to observe ET accurately, they have a limitation that the observation can stand for the exact site, not for an area. In this study, remote sensing technique is adopted to compensate the limitation of ground observation using the Moderate Resolution Imaging Spectroradiometer (MODIS) multispectral sensor mounted on Terra satellite. We improved to evapotranspiration model based on remote sensing (Mu et al., 2007) and estimated Penman-Monteith evapotranspiration considering regional characteristics of Korea that was using only MODIS product. We validated evapotranspiration of Sulma (SMK)/Cheongmi (CFK) flux tower observation and calculation. The results showed high correlation coefficient as 0.69 and 0.74.

Building Change Detection Using Deep Learning for Remote Sensing Images

  • Wang, Chang;Han, Shijing;Zhang, Wen;Miao, Shufeng
    • Journal of Information Processing Systems
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    • v.18 no.4
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    • pp.587-598
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    • 2022
  • To increase building change recognition accuracy, we present a deep learning-based building change detection using remote sensing images. In the proposed approach, by merging pixel-level and object-level information of multitemporal remote sensing images, we create the difference image (DI), and the frequency-domain significance technique is used to generate the DI saliency map. The fuzzy C-means clustering technique pre-classifies the coarse change detection map by defining the DI saliency map threshold. We then extract the neighborhood features of the unchanged pixels and the changed (buildings) from pixel-level and object-level feature images, which are then used as valid deep neural network (DNN) training samples. The trained DNNs are then utilized to identify changes in DI. The suggested strategy was evaluated and compared to current detection methods using two datasets. The results suggest that our proposed technique can detect more building change information and improve change detection accuracy.

China Dust-storm Monitoring Using Meteorological Satellite

  • Xiuqing, Hu;Naimeng, Lu;Peng, Zhang;Qian, Huang
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1224-1226
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    • 2003
  • Dust-storm is one of the heaviest hazardous weather which frequently affects most part of northern China in spring. Satellite multi-spectral observations can provide significant information for detecting and quantitative determining the property of dust-storm . An algorithm to monitor dust-storm automatically was developed based on satellite observation. The algorithm utilizes split widows technique and spectral classification technique and also developed a new dust remote sensing product Infra -red Difference Dust Index (IDDI) proxy dust-loading dataset using GMS-5.

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Three-Dimensional Positioning Using EROS A Stereo Pairs

  • Teo, Tee-Ann;Chen, Liang-Chien
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.606-608
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    • 2003
  • This paper investigates the accuracy of three-dimensional positioning for EROS A stereo pairs when different numbers of ground control points are employed. The major works of the proposed schemes include: (1) initialization of orientation parameters (2) preliminary orbit fitting, (3) orbit refinement using the least squares filtering technique, and (4) space intersection. The experiment includes validation of positioning accuracy for an EROS A in-track stereo pair when different number of check points are employed.

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