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Monitoring of landslide activity at the Sirobagarh landslide, Uttarakhand, India, using LiDAR, SAR interferometry and geodetic surveys / Ashutosh Tiwari in Geocarto international, vol 35 n° 5 ([01/04/2020])
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Titre : Monitoring of landslide activity at the Sirobagarh landslide, Uttarakhand, India, using LiDAR, SAR interferometry and geodetic surveys Type de document : Article/Communication Auteurs : Ashutosh Tiwari, Auteur ; Avadh Bihari Narayan, Auteur ; Ramji Dwivedi, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 535 - 558 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] arpentage
[Termes IGN] corrélation croisée maximale
[Termes IGN] covariance
[Termes IGN] données GNSS
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] effondrement de terrain
[Termes IGN] escarpement
[Termes IGN] image Sentinel-SAR
[Termes IGN] Inde
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] modèle numérique de surface
[Termes IGN] précipitation
[Termes IGN] surveillance géologique
[Termes IGN] tachéomètre électronique robotiséRésumé : (auteur) A robust geodetic framework comprising Terrestrial Laser Scanner (TLS), Global Navigation Satellite Systems (GNSS), Robotic Total Station (RTS) and Multi-temporal InSAR (MT-InSAR) was employed first in India to investigate a landslide-prone Sirobagarh region, Uttarakhand, at different spatial extents, and to evaluate the relationship amongst the displacement estimates obtained from the applied surveying techniques. TLS derived digital elevation models indicated displacements >5 m on the landslide upper scarp. GNSS- and RTS-based observations showed horizontal movements towards the Alaknanda river in the landslide slope direction (maximum values: 0.1305 and 0.045 m, respectively), and downward vertical motion (largest subsidence magnitude: −2.1315 and −0.030 m, respectively). MT-InSAR processing of Sentinel-1a images identified 21071 measurement pixels, highlighting subsidence around the landslide (mean velocity range: −0.110 to 0.008 m/year). Analysis of displacement vectors using vector equality, cross-covariance, cross-correlation and principal component analysis reveals that GNSS vertical displacement estimates were partially correlated with MT-InSAR measurements (correlated for epoch difference 2–3), whereas there was good cross-correlation between MT-InSAR and LiDAR observations throughout. The displacement estimates and their analyses evident unstable movement of the landslide scarp occurring due to debris flow and rainfall, and a relatively moderate subsidence activity in the surrounding areas lying in the landslide zone. Numéro de notice : A2020-144 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2018.1524516 Date de publication en ligne : 23/10/2018 En ligne : https://doi.org/10.1080/10106049.2018.1524516 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94770
in Geocarto international > vol 35 n° 5 [01/04/2020] . - pp 535 - 558[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2020051 RAB Revue Centre de documentation En réserve L003 Disponible Predictive mapping with small field sample data using semi‐supervised machine learning / Fei Du in Transactions in GIS, Vol 24 n° 2 (April 2020)
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Titre : Predictive mapping with small field sample data using semi‐supervised machine learning Type de document : Article/Communication Auteurs : Fei Du, Auteur ; A - Xing Zhu, Auteur ; Jing Liu, Auteur ; Lin Yang, Auteur Année de publication : 2020 Article en page(s) : pp 315 - 331 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] apprentissage semi-dirigé
[Termes IGN] covariance
[Termes IGN] échantillon
[Termes IGN] modèle de simulation
[Termes IGN] représentation cartographiqueRésumé : (Auteur) Existing predictive mapping methods usually require a large number of field samples with good representativeness as input to build reliable predictive models. In mapping practice, however, we often face situations when only small sample data are available. In this article, we present a semi‐supervised machine learning approach for predictive mapping in which the natural aggregation (clustering) patterns of environmental covariate data are used to supplement limited samples in prediction. This approach was applied to two soil mapping case studies. Compared with field sample only approaches (decision trees, logistic regression, and support vector machines), maps using the proposed approach can better capture the spatial variation of soil types and achieve higher accuracy with limited samples. A cross validation shows further that the proposed approach is less sensitive to the specific field sample set used and thus more robust when field sample data are small. Numéro de notice : A2020-174 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12598 Date de publication en ligne : 04/12/2019 En ligne : https://doi.org/10.1111/tgis.12598 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94900
in Transactions in GIS > Vol 24 n° 2 (April 2020) . - pp 315 - 331[article]Autocovariance-based perceptual textural features corresponding to human visual perception / N. Abbadeni (2020)
Titre : Autocovariance-based perceptual textural features corresponding to human visual perception Type de document : Article/Communication Auteurs : N. Abbadeni, Auteur ; D. Ziou, Auteur ; Shengrui Wang, Auteur Editeur : New-York : IEEE Computer society Année de publication : 2020 Conférence : ICPR 2000, 15th International Conference on Pattern Recognition 03/09/2000 07/09/2000 Barcelone Espagne Proceedings IEEE Importance : pp. 901 - 904 Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] covariance
[Termes IGN] psychologie
[Termes IGN] reconnaissance de formes
[Termes IGN] texture d'image
[Termes IGN] visionRésumé : (auteur) It has been shown that humans use some perceptual textural features such as coarseness, contrast and direction to distinguish between textured images or regions. The aim of this paper is to present a new method to estimate these perceptual textural features using the autocovariance function. Computational measures derived from the autocovariance function to estimate these perceptual textural features are presented. Experimental results are then given and the correspondence between the computational measures proposed and the psychological measures is shown using some psychometric method. Numéro de notice : C2000-027 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1109/ICPR.2000.903689 Date de publication en ligne : 06/08/2002 En ligne : https://doi.org/10.1109/ICPR.2000.903689 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103263 Embedding road networks and travel time into distance metrics for urban modelling / Henry Crosby in International journal of geographical information science IJGIS, Vol 33 n° 3-4 (March - April 2019)
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Titre : Embedding road networks and travel time into distance metrics for urban modelling Type de document : Article/Communication Auteurs : Henry Crosby, Auteur ; theodore Damoulas, Auteur ; Stephen A. Jarvis, Auteur Année de publication : 2019 Article en page(s) : pp 512 - 536 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] covariance
[Termes IGN] distance euclidienne
[Termes IGN] durée de trajet
[Termes IGN] espace-temps
[Termes IGN] géostatistique
[Termes IGN] isométrie
[Termes IGN] krigeage
[Termes IGN] logement
[Termes IGN] modèle de simulation
[Termes IGN] réseau routier
[Termes IGN] trafic routier
[Termes IGN] urbanisme
[Termes IGN] variogrammeRésumé : (auteur) Urban environments are restricted by various physical, regulatory and customary barriers such as buildings, one-way systems and pedestrian crossings. These features create challenges for predictive modelling in urban space, as most proximity-based models rely on Euclidean (straight line) distance metrics which, given restrictions within the urban landscape, do not fully capture spatial urban processes. Here, we argue that road distance and travel time provide effective alternatives, and we develop a new low-dimensional Euclidean distance metric based on these distances using an isomap approach. The purpose of this is to produce a valid covariance matrix for Kriging. Our primary methodological contribution is the derivation of two symmetric dissimilarity matrices (B+ and B2+), with which it is possible to compute low-dimensional Euclidean metrics for the production of a positive definite covariance matrix with commonly utilised kernels. This new method is implemented into a Kriging predictor to estimate house prices on 3,669 properties in Coventry, UK. We find that a metric estimating a combination of road distance and travel time, in both R2 and R3, produces a superior house price predictor compared with alternative state-of-the-art methods, that is, a standard Euclidean metric in RN and a non-restricted road distance metric in R2 and R3. F Numéro de notice : A2019-024 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2018.1547386 Date de publication en ligne : 06/12/2018 En ligne : https://doi.org/10.1080/13658816.2018.1547386 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91952
in International journal of geographical information science IJGIS > Vol 33 n° 3-4 (March - April 2019) . - pp 512 - 536[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2019031 RAB Revue Centre de documentation En réserve L003 Disponible 079-2019032 RAB Revue Centre de documentation En réserve L003 Disponible
Titre : Contributions to SAR image time series analysis Type de document : Thèse/HDR Auteurs : Ammar Mian, Auteur ; Jean-Philippe Ovarlez, Directeur de thèse ; Guillaume Ginolhac, Directeur de thèse Editeur : Bures-sur-Yvette : Université Paris-Saclay Année de publication : 2019 Importance : 219 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse de Doctorat de l’Université Paris-Saclay préparée à Centrale-Supélec : Sciences et Technologies de l’Information et de la CommunicationLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] covariance
[Termes IGN] détection de changement
[Termes IGN] géométrie de Riemann
[Termes IGN] image à très haute résolution
[Termes IGN] image radar moirée
[Termes IGN] ondelette de Shannon
[Termes IGN] processus gaussien
[Termes IGN] radar à antenne synthétique
[Termes IGN] série temporelle
[Termes IGN] transformation en ondelettesIndex. décimale : THESE Thèses et HDR Résumé : (auteur) Remote sensing data from Synthetic Aperture Radar (SAR) sensors offer a unique opportunity to record, to analyze, and to predict the evolution of the Earth. In the last decade, numerous satellite remote sensing missions have been launched (Sentinel-1, UAVSAR, TerraSAR X, etc.). This resulted in a dramatic improvement in the Earth image acquisition capability and accessibility. The growing number of observation systems allows now to build high temporal/spatial-resolution Earth surface images data-sets. This new scenario significantly raises the interest in time-series processing to monitor changes occurring over large areas. However, developing new algorithms to process such a huge volume of data represents a current challenge. In this context, the present thesis aims at developing methodologies for change detection in high-resolution SAR image time series.These series raise two notable challenges that have to be overcome:On the one hand, standard statistical methods rely on multivariate data to infer a result which is often superior to a monovariate approach. Such multivariate data is however not always available when it concerns SAR images. To tackle this issue, new methodologies based on wavelet decomposition theory have been developed to fetch information based on the physical behavior of the scatterers present in the scene.On the other hand, the improvement in resolution obtained from the latest generation of sensors comes with an increased heterogeneity of the data obtained. For this setup, the standard Gaussian assumption used to develop classic change detection methodologies is no longer valid. As a consequence, new robust methodologies have been developed considering the family of elliptical distributions which have been shown to better fit the observed data.The association of both aspects has shown promising results in change detection applications. Note de contenu : Introduction
1- SAR Image Time Series issues
2- Wavelet packets for SAR analysis
3- Robust Change Detection
4- Change-point detection and estimation
5- Riemannian geometry
ConclusionNuméro de notice : 25872 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse française Note de thèse : Thèse de Doctorat : Sciences et Technologies de l’Information et de la Communication : Paris-Saclay : 2019 Organisme de stage : Laboratoire SONDRA nature-HAL : Thèse DOI : sans En ligne : https://tel.archives-ouvertes.fr/tel-02464840/document Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95547 Enhancing the predictability of least-squares collocation through the integration with least-squares-support vector machine / Hossam Talaat Elshambaky in Journal of applied geodesy, vol 13 n° 1 (January 2019)PermalinkExercices corrigés de géostatistique / Chantal de Fouquet (2019)PermalinkPermalinkDétermination d’un modèle géopotentiel à haute résolution en zone littorale aidé par des mesures d’horloges atomiques / Hugo Lecomte (2018)PermalinkAnalyse du bilan d’erreur appliquée aux systèmes de levés hydrographiques de surface et sous-marin / Geraud Naankeu-Wati in XYZ, n° 152 (septembre - novembre 2017)PermalinkDetermination of a high spatial resolution geopotential model using atomic clock comparisons / Guillaume Lion in Journal of geodesy, vol 91 n° 6 (June 2017)PermalinkSpace-wise approach for airborne gravity data modelling / Daniele Sampietro in Journal of geodesy, vol 91 n° 5 (May 2017)PermalinkIntegrating uncertainty propagation in GNSS radio occultation retrieval: From bending angle to dry-air atmospheric profiles / Jakob Schwarz in Earth and space science, vol 4 n° 4 (April 2017)PermalinkSystematic effects in laser scanning and visualization by confidence regions / Karl Rudolf Koch in Journal of applied geodesy, vol 10 n° 4 (December 2016)PermalinkAdaptive GPS/INS integration for relative navigation / Je Young Lee in GPS solutions, vol 20 n° 1 (January 2016)Permalink