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Ground surface elevation changes over permafrost areas revealed by multiple GNSS interferometric reflectometry / Yufeng Hu in Journal of geodesy, vol 96 n° 8 (August 2022)
[article]
Titre : Ground surface elevation changes over permafrost areas revealed by multiple GNSS interferometric reflectometry Type de document : Article/Communication Auteurs : Yufeng Hu, Auteur ; Ji Wang, Auteur ; Zhenhong Li, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 56 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Alaska (Etats-Unis)
[Termes IGN] analyse diachronique
[Termes IGN] dégel
[Termes IGN] données Galileo
[Termes IGN] données GLONASS
[Termes IGN] pergélisol
[Termes IGN] rapport signal sur bruit
[Termes IGN] réflecteur
[Termes IGN] réflectométrie par GNSS
[Termes IGN] signal GNSS
[Termes IGN] surface du sol
[Termes IGN] variation saisonnièreRésumé : (auteur) Ground subsidence and uplift caused by the annual thawing and freezing of the active layer are important variables in permafrost studies. Global positioning system interferometric reflectometry (GPS-IR) has been successfully applied to retrieve the continuous ground surface movements in permafrost areas. However, only GPS signals were used in previous studies. In this study, using multiple global navigation satellite system (GNSS) signal-to-noise ratio (SNR) observations recorded by a GNSS station SG27 in Utqiaġvik, Alaska during the period from 2018 to 2021, we applied multiple GNSS-IR (multi-GNSS-IR) technique to the SNR data and obtained the complete and continuous ground surface elevation changes over the permafrost area at a daily interval in snow-free seasons in 2018 and 2019. The GLONASS-IR and Galileo-IR measurements agreed with the GPS-IR measurements at L1 frequency, which are the most consistent measurements among all multi-GNSS measurements, in terms of the overall subsidence trend but clearly showed periodic noises. We proposed a method to reconstruct the GLONASS- and Galileo-IR elevation changes by specifically grouping and fitting them with a composite model. Compared with GPS L1 results, the unbiased root mean square error (RMSE) of the reconstructed Galileo measurements reduced by 50.0% and 42.2% in 2018 and 2019, respectively, while the unbiased RMSE of the reconstructed GLONASS measurements decreased by 41.8% and 25.8% in 2018 and 2019, respectively. Fitting the composite model to the combined multi-GNSS-IR, we obtained seasonal displacements of − 3.27 ± 0.13 cm (R2 = 0.763) and − 10.56 ± 0.10 cm (R2 = 0.912) in 2018 and 2019, respectively. Moreover, we found that the abnormal summer heave was strongly correlated with rain events, implying hydrological effects on the ground surface elevation changes. Our study shows the feasibility of multi-GNSS-IR in permafrost areas for the first time. Multi-GNSS-IR opens up a great opportunity for us to investigate ground surface movements over permafrost areas with multi-source observations, which are important for our robust analysis and quantitative understanding of frozen ground dynamics under climate change. Numéro de notice : A2022-606 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-022-01646-5 Date de publication en ligne : 13/08/2022 En ligne : https://doi.org/10.1007/s00190-022-01646-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101385
in Journal of geodesy > vol 96 n° 8 (August 2022) . - n° 56[article]Physical modelling of Nanda Devi National Park, a natural world heritage site, from GIS data / Sanat Agrawal in Cartographica, vol 57 n° 2 (Summer 2022)
[article]
Titre : Physical modelling of Nanda Devi National Park, a natural world heritage site, from GIS data Type de document : Article/Communication Auteurs : Sanat Agrawal, Auteur ; Akshay Jain, Auteur Année de publication : 2022 Article en page(s) : pp 179 - 194 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] conservation du patrimoine
[Termes IGN] Himalaya
[Termes IGN] Inde
[Termes IGN] modèle numérique de surface
[Termes IGN] modèle physique
[Termes IGN] patrimoine naturel
[Termes IGN] QGIS
[Termes IGN] site
[Termes IGN] surface du sol
[Termes IGN] système d'information géographiqueRésumé : (auteur) A methodology has been developed to create a physical model of the Nanda Devi National Park (NDNP), a Natural World Heritage Site (NWHS), by additive fabrication, to facilitate effective communication among the stakeholders for conservation management. The GIS data of a terrain give elevation values on the surface of a terrain only and lack 3D definition. The DEM ASCII XYZ file format is converted into a 3D STL file with walls and a base. Gaps and singularities in the data are taken care of. There is ample scope for aiding conservation management and restoration of NWHS sites using additive manufacturing (AM). A physical model of the NDNP was created using the methodology. The model holds very high value for long-term monitoring of the NWHS and the Himalayas. The physical model of the NDNP can serve as an effective medium of communication for conservation management. Physical models of the glacial basins or the Nanda Devi peak will provide further value. The research work can be extended to making models of the NDNP of larger sizes or by focusing on smaller region of the NDNP in consultation with the stakeholders. Numéro de notice : A2022-636 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3138/cart-2021-0025 Date de publication en ligne : 25/06/2022 En ligne : https://doi.org/10.3138/cart-2021-0025 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101426
in Cartographica > vol 57 n° 2 (Summer 2022) . - pp 179 - 194[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 031-2022021 RAB Revue Centre de documentation En réserve L003 Disponible Saline-soil deformation extraction based on an improved time-series InSAR approach / Wei Xiang in ISPRS International journal of geo-information, vol 10 n° 3 (March 2021)
[article]
Titre : Saline-soil deformation extraction based on an improved time-series InSAR approach Type de document : Article/Communication Auteurs : Wei Xiang, Auteur ; Rui Zhang, Auteur ; Guoxiang Liu, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 112 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande C
[Termes IGN] Chine
[Termes IGN] déformation de surface
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] image radar moirée
[Termes IGN] image Sentinel-SAR
[Termes IGN] série temporelle
[Termes IGN] sol salin
[Termes IGN] surface du sol
[Termes IGN] variation saisonnièreRésumé : (auteur) Significant seasonal fluctuations could occur in the regional scattering characteristics and surface deformation of saline soil, and cause decorrelation, which limits the application of the conventional time-series InSAR (TS-InSAR). For extending the saline-soil deformation monitoring capability, this paper presents an improved TS-InSAR approach, based on the interferometric coherence statistics and high-coherence interferogram refinement. By constructing a network of the refined interferograms, high-accuracy ground deformation can be extracted through the weighted least square estimation and the coherent target refinement. To extract the high-accuracy deformation of a representative saline soil area in the Qarhan Salt Lake, 119 C-band Sentinel-1A images collected between May 2015 and May 2020 are selected as the data source. Subsequently, 845 refined interferograms are selected from all possible interferograms to conduct the network inversion, based on the related thresholds (the temporal baseline 0.5, respectively). Compared with the conventional TS-InSAR measurements, both the accuracy and reliability of the extracted deformation results of the saline soil increased dramatically. Furthermore, the testing results indicate that the improved TS-InSAR method has advantages on the deformation extraction in the saline soil region, and is adaptive to reflecting the typical seasonal variations of the saline soil. Numéro de notice : A2021-234 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/ijgi10030112 Date de publication en ligne : 27/02/2021 En ligne : https://doi.org/10.3390/ijgi10030112 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97230
in ISPRS International journal of geo-information > vol 10 n° 3 (March 2021) . - n° 112[article]Fusion of ground penetrating radar and laser scanning for infrastructure mapping / Dominik Merkle in Journal of applied geodesy, vol 15 n° 1 (January 2021)
[article]
Titre : Fusion of ground penetrating radar and laser scanning for infrastructure mapping Type de document : Article/Communication Auteurs : Dominik Merkle, Auteur ; Carsten Frey, Auteur ; Alexander Reiterer, Auteur Année de publication : 2021 Article en page(s) : pp 31 - 45 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] base de données localisées 3D
[Termes IGN] données lidar
[Termes IGN] espace de Hilbert
[Termes IGN] lasergrammétrie
[Termes IGN] lever souterrain
[Termes IGN] radar pénétrant GPR
[Termes IGN] radargrammétrie
[Termes IGN] réseau technique souterrain
[Termes IGN] semis de points
[Termes IGN] sous-sol
[Termes IGN] surface du sol
[Termes IGN] système de numérisation mobileRésumé : (auteur) Mobile mapping vehicles, equipped with cameras, laser scanners (in this paper referred to as light detection and ranging, LiDAR), and positioning systems are limited to acquiring surface data. However, in this paper, a method to fuse both LiDAR and 3D ground penetrating radar (GPR) data into consistent georeferenced point clouds is presented, allowing imaging both the surface and subsurface. Objects such as pipes, cables, and wall structures are made visible as point clouds by thresholding the GPR signal’s Hilbert envelope. The results are verified with existing utility maps. Varying soil conditions, clutter, and noise complicate a fully automatized approach. Topographic correction of the GPR data, by using the LiDAR data, ensures a consistent ground height. Moreover, this work shows that the LiDAR point cloud, as a reference, increases the interpretability of GPR data and allows measuring distances between above ground and subsurface structures. Numéro de notice : A2021-044 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1515/jag-2020-0004 Date de publication en ligne : 06/11/2020 En ligne : https://doi.org/10.1515/jag-2020-0004 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96771
in Journal of applied geodesy > vol 15 n° 1 (January 2021) . - pp 31 - 45[article]Local terrain modification method considering physical feature constraints for vector elements / Jiangfeng She in Cartography and Geographic Information Science, Vol 47 n° 5 (September 2020)
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Titre : Local terrain modification method considering physical feature constraints for vector elements Type de document : Article/Communication Auteurs : Jiangfeng She, Auteur ; Junyan Liu, Auteur ; Junzhong Tan, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 452 - 470 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] altitude
[Termes IGN] analyse vectorielle
[Termes IGN] contrainte d'intégrité
[Termes IGN] déformation de surface
[Termes IGN] données vectorielles
[Termes IGN] interpolation
[Termes IGN] processeur graphique
[Termes IGN] rastérisation
[Termes IGN] relief
[Termes IGN] superposition de données
[Termes IGN] surface du sol
[Termes IGN] terrain
[Termes IGN] traitement parallèle
[Termes IGN] zone tamponRésumé : (auteur) Many studies have been focused on rendering 2D vector elements on 3D terrain, and a series of algorithms have been proposed. Most of these algorithms struggle to provide a seamless overlay between vector elements and an irregular terrain surface. Despite their importance, the physical characteristics of vector elements are often ignored, which distorts the surface of vector elements. For example, if vector elements that represent roads and rivers are simply overlaid on terrain, the phenomena of uneven surfaces and rivers going uphill may occur because of elevation fluctuation. To correct these deficiencies, terrain should be modified according to the physical characteristics of vectors. We propose a local terrain modification method: First, the elevation of terrain covered by vector elements is recalculated according to vectors’ physical characteristics. Second, the multigrid method is used to realize a smooth transition between the modified terrain and its surrounding area. Finally, by setting different transition ranges and comparing the visualization effects, rules are given for the selection of a suitable range. After modification, the terrain conforms to vectors’ physical characteristics, and the overall relief is undamaged. The proposed method was applied to a CPU–GPU parallel heterogeneous model and demonstrated a high level of performance. Numéro de notice : A2020-489 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/MATHEMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/15230406.2020.1770128 Date de publication en ligne : 06/07/2020 En ligne : https://doi.org/10.1080/15230406.2020.1770128 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95660
in Cartography and Geographic Information Science > Vol 47 n° 5 (September 2020) . - pp 452 - 470[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 032-2020051 RAB Revue Centre de documentation En réserve L003 Disponible Evaluation of seasonal variations of remotely sensed leaf area index over five evergreen coniferous forests / Rong Wang in ISPRS Journal of photogrammetry and remote sensing, vol 130 (August 2017)PermalinkTransferability of multi- and hyperspectral optical biocrust indices / Emilio Rodríguez-Caballero in ISPRS Journal of photogrammetry and remote sensing, vol 126 (April 2017)PermalinkFaraday rotation correction for the SMAP radiometer / David M. Le Vine in IEEE Transactions on geoscience and remote sensing, vol 54 n° 4 (April 2016)PermalinkAn accurate and computationally efficient algorithm for ground peak identification in large footprint waveform LiDAR data / Wei Zhuang in ISPRS Journal of photogrammetry and remote sensing, vol 95 (September 2014)PermalinkTowards linking aboveground vegetation properties and soil microbial communities using remote sensing / Yuki Hamada in Photogrammetric Engineering & Remote Sensing, PERS, vol 80 n° 4 (April 2014)PermalinkA novel technique for the automatic detection of surface clutter returns in radar sounder data / Adam Ferro in IEEE Transactions on geoscience and remote sensing, vol 51 n° 5 Tome 2 (May 2013)PermalinkParametric investigation of the performance of Lidar filters using different surface contexts / S. Seo in Photogrammetric Engineering & Remote Sensing, PERS, vol 74 n° 3 (March 2008)PermalinkDetermination of robust spectral features for identification of urban surface materials in hyperspectral remote sensing data / U. Heiden in Remote sensing of environment, vol 111 n° 4 (28/12/2007)PermalinkContribution à l'étude de la désertification dans le sud oranais / A. Hirche in Revue Française de Photogrammétrie et de Télédétection, n° 187 -188 (Décembre 2007)PermalinkLidar et applications en géophysique externe / P.H. Flamant in Revue Française de Photogrammétrie et de Télédétection, n° 186 (Juin 2007)Permalink