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Global and climate challenges, graph-based data analysis for multisource information extraction / Morgane Batelier (2022)
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Titre : Global and climate challenges, graph-based data analysis for multisource information extraction Type de document : Mémoire Auteurs : Morgane Batelier, Auteur Editeur : Champs-sur-Marne : Ecole nationale des sciences géographiques ENSG Année de publication : 2022 Importance : 43 p. Format : 21 x 30 cm Note générale : Bibliographie
Mémoire de fin d'études, cycle des ingénieurs ENSG 3ème année, FRSLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] apprentissage automatique
[Termes IGN] Arctique, océan
[Termes IGN] données d'entrainement sans étiquette
[Termes IGN] glace de mer
[Termes IGN] image hyperspectrale
[Termes IGN] image Sentinel-SAR
[Termes IGN] polarimétrie radar
[Termes IGN] traitement d'image radarIndex. décimale : MPT Mémoires de fin d'études du Master Méthodes physiques en télédétection Résumé : (Auteur) During my end-of-studies internship, I worked on the development of a label propagation algorithm for remote sensing data, using Deep Learning. It was mainly applied to sea ice classification using SAR Sentinel-1 data, and to hyperspectral imaging in order to be effective to multimodal remote sensing. I started by the bibliography, during which we decided with my supervisors the method I was going to work from. Then, I worked on the algorithm implementation that was the longest phase. Finally, the last part of my work was the certification and improvement of the results using different process. Note de contenu : Introduction
1. Remote Sensing in the Arctic
1.1 Challenges of the Arctic
1.2 Sea Ice
2. Label Propagation for Deep Learning
2.1 Preliminaries
2.2 Transductive Propagation Network for Few-shot Learning
3. Multimodal Remote Sensing Data
3.1 Synthetic Aperture Radar
3.2 Hyperspectral Imaging
4. Experimental results
4.1 Datasets
4.2 Improvement Methods
4.3 Discussion and future of the algorithm
ConclusionNuméro de notice : 26935 Affiliation des auteurs : non IGN Thématique : IMAGERIE/INFORMATIQUE Nature : Mémoire de fin d'études IT Organisme de stage : Center for Integrated Remote Sensing and Forecasting for Arctic Operations CIRFA Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102059 Documents numériques
en open access
Global and climate challenges, graph-based data analysis for multisource information extraction - pdf auteurAdobe Acrobat PDFSeven decades of coastal change at Barter Island, Alaska: Exploring the importance of waves and temperature on erosion of coastal permafrost bluffs / Ann E. Gibbs in Remote sensing, vol 13 n° 21 (November-1 2021)
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Titre : Seven decades of coastal change at Barter Island, Alaska: Exploring the importance of waves and temperature on erosion of coastal permafrost bluffs Type de document : Article/Communication Auteurs : Ann E. Gibbs, Auteur ; Li H. Erikson, Auteur ; Benjamin M. Jones, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 4420 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Alaska (Etats-Unis)
[Termes IGN] analyse diachronique
[Termes IGN] Beaufort, mer de
[Termes IGN] détection de changement
[Termes IGN] données météorologiques
[Termes IGN] ERA5
[Termes IGN] érosion côtière
[Termes IGN] modèle météorologique
[Termes IGN] pergélisol
[Termes IGN] série temporelle
[Termes IGN] température de l'air
[Termes IGN] température de surface de la mer
[Termes IGN] trait de côte
[Termes IGN] vagueRésumé : (auteur) Observational data of coastal change over much of the Arctic are limited largely due to its immensity, remoteness, harsh environment, and restricted periods of sunlight and ice-free conditions. Barter Island, Alaska, is one of the few locations where an extensive, observational dataset exists, which enables a detailed assessment of the trends and patterns of coastal change over decadal to annual time scales. Coastal bluff and shoreline positions were delineated from maps, aerial photographs, and satellite imagery acquired between 1947 and 2020, and at a nearly annual rate since 2004. Rates and patterns of shoreline and bluff change varied widely over the observational period. Shorelines showed a consistent trend of southerly erosion and westerly extension of the western termini of Barter Island and Bernard Spit, which has accelerated since at least 2000. The 3.2 km long stretch of ocean-exposed coastal permafrost bluffs retreated on average 114 m and at a maximum of 163 m at an average long-term rate (70 year) of 1.6 ± 0.1 m/yr. The long-term retreat rate was punctuated by individual years with retreat rates up to four times higher (6.6 ± 1.9 m/yr; 2012–2013) and both long-term (multidecadal) and short-term (annual to semiannual) rates showed a steady increase in retreat rates through time, with consistently high rates since 2015. A best-fit polynomial trend indicated acceleration in retreat rates that was independent of the large spatial and temporal variations observed on an annual basis. Rates and patterns of bluff retreat were correlated to incident wave energy and air and water temperatures. Wave energy was found to be the dominant driver of bluff retreat, followed by sea surface temperatures and warming air temperatures that are considered proxies for evaluating thermo-erosion and denudation. Normalized anomalies of cumulative wave energy, duration of open water, and air and sea temperature showed at least three distinct phases since 1979: a negative phase prior to 1987, a mixed phase between 1987 and the early to late 2000s, followed by a positive phase extending to 2020. The duration of the open-water season has tripled since 1979, increasing from approximately 40 to 140 days. Acceleration in retreat rates at Barter Island may be related to increases in both thermodenudation, associated with increasing air temperature, and the number of niche-forming and block-collapsing episodes associated with higher air and water temperature, more frequent storms, and longer ice-free conditions in the Beaufort Sea. Numéro de notice : A2021-822 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/rs13214420 Date de publication en ligne : 04/11/2021 En ligne : https://doi.org/10.3390/rs13214420 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98936
in Remote sensing > vol 13 n° 21 (November-1 2021) . - n° 4420[article]Extraction of sea ice cover by Sentinel-1 SAR based on support vector machine with unsupervised generation of training data / Xiao-Ming Li in IEEE Transactions on geoscience and remote sensing, vol 59 n° 4 (April 2021)
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Titre : Extraction of sea ice cover by Sentinel-1 SAR based on support vector machine with unsupervised generation of training data Type de document : Article/Communication Auteurs : Xiao-Ming Li, Auteur ; Yan Sun, Auteur ; Qiang Zhang, Auteur Année de publication : 2021 Article en page(s) : pp 3040 - 3053 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] Arctique, océan
[Termes IGN] classification non dirigée
[Termes IGN] classification par séparateurs à vaste marge
[Termes IGN] données d'entrainement (apprentissage automatique)
[Termes IGN] entropie
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] glace de mer
[Termes IGN] image radar moirée
[Termes IGN] image Sentinel-SAR
[Termes IGN] matrice de co-occurrence
[Termes IGN] niveau de gris (image)
[Termes IGN] polarisation croisée
[Termes IGN] rétrodiffusion
[Termes IGN] texture d'imageRésumé : (auteur) In this article, we focus on developing a novel method to extract sea ice cover (i.e., discrimination/classification of sea ice and open water) using Sentinel-1 (S1) cross-polarization [vertical–horizontal (VH) or horizontal–vertical (HV)] data in extra-wide (EW) swath mode based on the support vector machine (SVM) method. The classification basis includes the S1 radar backscatter and texture features, which are calculated from S1 data using the gray level co-occurrence matrix (GLCM). Different from previous methods where appropriate samples are manually selected to train the SVM to classify sea ice and open water, we proposed a method of unsupervised generation of the training samples based on two GLCM texture features, i.e., entropy and homogeneity, that have contrasting characteristics on sea ice and open water. We eliminate the most uncertainty of selecting training samples in machine learning and achieve automatic classification of sea ice and open water by using S1 EW data. The comparisons based on a few cases show good agreements between the synthetic aperture radar (SAR)-derived sea ice cover using the proposed method and visual inspections, of which the accuracy reaches approximately 90%–95%. Besides this, compared with the analyzed sea ice cover data Ice Mapping System (IMS) based on 728 S1 EW images, the accuracy of the extracted sea ice cover by using S1 data is more than 80%. Numéro de notice : A2021-284 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2020.3007789 Date de publication en ligne : 20/07/2020 En ligne : https://doi.org/10.1109/TGRS.2020.3007789 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97392
in IEEE Transactions on geoscience and remote sensing > vol 59 n° 4 (April 2021) . - pp 3040 - 3053[article]Discrimination of different sea ice types from CryoSat-2 satellite data using an Object-based Random Forest (ORF) / Su Shu in Marine geodesy, Vol 43 n° 3 (May 2020)
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Titre : Discrimination of different sea ice types from CryoSat-2 satellite data using an Object-based Random Forest (ORF) Type de document : Article/Communication Auteurs : Su Shu, Auteur ; Xinghua Zhou, Auteur ; Zhanchi Liu, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 213 - 233 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] Arctique, océan
[Termes IGN] classification orientée objet
[Termes IGN] classification par forêts d'arbres décisionnels
[Termes IGN] forme d'onde
[Termes IGN] glace de mer
[Termes IGN] image CryosatRésumé : (Auteur) Sea ice type is one of the most sensitive variables in Arctic sea ice monitoring, and it is important for the retrieval of ice thickness. In this study, we analyzed various waveform features that characterize the echo waveform shape and Sigma0 (i.e., backscatter coefficient) of CryoSat-2 synthetic aperture radar altimeter data over different sea ice types. Arctic and Antarctic Research Institute operational ice charts were input as reference. An object-based random forest (ORF) classification method is proposed with overall classification accuracy of 90.1%. Accuracy of 92.7% was achieved for first-year ice (FYI), which is the domain ice type in the Arctic. Accuracy of 76.7% was achieved at the border of FYI and multiyear ice (MYI), which is better than current state-of-the-art methods. Accuracy of 83.8% was achieved for MYI. Results showed the overall accuracy of the ORF method was increased by ∼8% in comparison with other methods, and the classification accuracy at the border of FYI and MYI was increased by ∼10.5%. Nevertheless, ORF classification performance might be influenced by the selected waveform features, snow loading, and the ability to distinguish sea ice from leads. Numéro de notice : A2020-183 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01490419.2019.1671560 Date de publication en ligne : 21/10/2019 En ligne : https://doi.org/10.1080/01490419.2019.1671560 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94971
in Marine geodesy > Vol 43 n° 3 (May 2020) . - pp 213 - 233[article]Improved arctic ocean mass variability inferred from time-variable gravity with constraints and dual leakage correction / Dapeng Mu in Marine geodesy, Vol 43 n° 3 (May 2020)
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Titre : Improved arctic ocean mass variability inferred from time-variable gravity with constraints and dual leakage correction Type de document : Article/Communication Auteurs : Dapeng Mu, Auteur ; Tianhe Xu, Auteur ; Guochang Xu, Auteur Année de publication : 2020 Article en page(s) : pp 269 - 284 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] Arctique, océan
[Termes IGN] données GRACE
[Termes IGN] harmonique sphérique
[Termes IGN] marée océaniqueRésumé : (Auteur) The ocean mass variability inferred from Gravity Recovery and Climate Experiment (GRACE) satellites mission is challenged by the stripes and the leakage across land-ocean boundary. The recently released GRACE mascons solutions are advanced by applying constraints that remove efficiently the stripes and dual leakage correction that restores the coastal ocean mass variability. Here we quantitatively evaluate the improvement in the Arctic Ocean mass variability by GRACE mascons. To do so, we compare the combination of GRACE solutions (including the mascons solutions and traditional spherical harmonic coefficients (SHCs) solutions) and the steric estimates against the altimeter observations. Our results suggest that mascons solutions produce stronger correlations compared to SHCs solutions, especially along the coastal zone, indicating the importance of the dual leakage correction. Stronger correlation is produced by the mascons over a small basin in the interior of the Arctic Ocean, suggesting that mascons solutions deliver better ocean mass variability than the SHCs solutions. Since the comparisons are carried out over two sub-basins, we conclude that mascons are able to provide better regional ocean mass variability that may have implications for regional sea level budget, in particular over the coastal zone. Numéro de notice : A2020-185 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01490419.2020.1711832 Date de publication en ligne : 17/01/2020 En ligne : https://doi.org/10.1080/01490419.2020.1711832 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94975
in Marine geodesy > Vol 43 n° 3 (May 2020) . - pp 269 - 284[article]Arctic sea ice thickness retrievals from CryoSat-2: seasonal and interannual comparisons of three different products / Mengmeng Li in International Journal of Remote Sensing IJRS, vol 41 n° 1 (01 - 08 janvier 2020)
PermalinkPhotogrammetric Bathymetry for the Canadian Arctic / Matus Hodul in Marine geodesy, Vol 43 n° 1 (January 2020)
PermalinkPermalinkEnhanced MODIS atmospheric total water vapour content trends in response to Arctic amplification / Dunya Alraddawi in Atmosphere, vol 8 n° 12 (December 2017)
PermalinkGPS coordinate time series measurements in Ontario and Quebec, Canada / Hadis Samadi Alinia in Journal of geodesy, vol 91 n° 6 (June 2017)
PermalinkCharacterization of Arctic sea ice thickness using high-resolution spaceborne polarimetric SAR data / J.W. Kim in IEEE Transactions on geoscience and remote sensing, vol 50 n° 1 (January 2012)
PermalinkMapping the North : the updated North Circumpolar Region map by the atlas of Canada / R.E. Kramers in Cartographica, vol 45 n° 3 (September 2010)
PermalinkAmundsen Sea bathymetry: the benefits of using gravity data for bathymetric prediction / M. Mcmillan in IEEE Transactions on geoscience and remote sensing, vol 47 n° 12 Tome 2 (December 2009)
PermalinkDEM control in Arctic Alaska with Icesat laser altimetry / D.K. Atwood in IEEE Transactions on geoscience and remote sensing, vol 45 n° 11 Tome 2 (November 2007)
PermalinkAssessment of EOS aqua AMSR-E artic sea ice concentrations using Landsat-7 and airborne microwave imagery / D.J. Cavalieri in IEEE Transactions on geoscience and remote sensing, vol 44 n° 11 Tome 1 (November 2006)
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