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Titre : Surface reconstruction based on forest terrestrial LiDAR data Type de document : Thèse/HDR Auteurs : Jules Morel, Auteur ; Marc Daniel, Directeur de thèse ; Cédric Vega , Directeur de thèse ; Alexandra Bac, Directeur de thèse
Editeur : Aix-en-Provence : Université d'Aix-Marseille Année de publication : 2017 Importance : 178 p. Format : 21 x 30 cm Note générale : bibliographie
A dissertation presented to the Department of Mathématique et Informatique in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the subject of Computer ScienceLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] distribution de Poisson
[Termes IGN] données lidar
[Termes IGN] données TLS (télémétrie)
[Termes IGN] fonction de base radiale
[Termes IGN] interpolation
[Termes IGN] modélisation de la forêt
[Termes IGN] placette d'échantillonnage
[Termes IGN] reconstruction d'objet
[Termes IGN] semis de points
[Termes IGN] structure d'un peuplement forestier
[Termes IGN] structure de la végétationIndex. décimale : THESE Thèses et HDR Résumé : (auteur) In recent years, the capacity of LiDAR technology to capture detailed information about forests structure has attracted increasing attention in the field of forest science. In particular, the terrestrial LiDAR arises as a promising tool to retrieve geometrical characteristics of trees at a millimeter level. This thesis studies the surface reconstruction problem from scattered and unorganized point
clouds, captured in forested environment by a terrestrial LiDAR. We propose a sequence of algorithms dedicated to the reconstruction of forests plot attributes model: the ground and the woody structure of trees (i.e. the trunk and the main branches). In practice, our approaches model the surface with implicit function build with radial basis functions to manage the homogeneity and handle the noise of the sample data points. Our first focus is on the reconstruction of the ground surface whose level of detail is based on local complexity, through alternation between scale refinement, filtering and reconstruction. The result arises from the polygonization of the implicit function expressed as the merging of local approximations by compactly supported radial basis function used as partition of unity. Once the ground is modeled, the topology effects can be ignored in the following computation steps that focus on the modeling of trees. Traditionally, the processing of the woody part is achieved by a discrete reconstruction in the form of a stack of independent building blocks. From such a model, our approach developed for the ground is adapted to approximate the woody part of the tree by a more flexible continuous surface. Expressed as an implicit function, the tree model can be refined by an additional computational step in order to describe precisely the geometry. With this in mind, we propose a method dedicated to the fine reconstruction of occluded objects: from 3D samples presenting occlusions,
we use the previously described continuous model to guide a Poisson surface reconstruction. Thus, we guarantee the production of a watertight surface that approximates sharply the point cloud in the visible areas and extrapolates consistently the tree shape in the occlusions.Note de contenu : 1- Introduction
2- Terrestrial LiDAR scanning in forests
3- Survey on surface reconstruction
4- Reconstruction of open surface
5- Geometric model of trees
6- Reconstruction of partially occluded objects
7- Conclusion and perspectivesNuméro de notice : 25855 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : IMAGERIE Nature : Thèse française Note de thèse : PhD Thesis: Computer Science : Marseille : 2017 Organisme de stage : Institut Français de Pondichéri (Inde) nature-HAL : Thèse DOI : sans En ligne : http://www.theses.fr/2017AIXM0039 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95472
Titre : Understanding GPS/GNSS : principles and applications Type de document : Monographie Auteurs : Elliott D. Kaplan, Éditeur scientifique ; Christopher Hegarty, Éditeur scientifique Mention d'édition : Third edition Editeur : Londres, Washington : Artech House Année de publication : 2017 Collection : GNSS Technology and applications series Importance : 993 p. Format : 18 x 26 cm ISBN/ISSN/EAN : 978-1-63081-058-0 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] BeiDou
[Termes IGN] erreur de positionnement
[Termes IGN] Galileo
[Termes IGN] Global Orbitography Navigation Satellite System
[Termes IGN] Global Positioning System
[Termes IGN] GNSS en mode différentiel
[Termes IGN] mesurage par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] récepteur GNSSIndex. décimale : 30.61 Systèmes de Positionnement par Satellites du GNSS Résumé : (Editeur) This updated third edition provides a current and comprehensive treatment of global navigation satellite systems (GNSS) and includes new chapters on the system engineering details of GPS, European Galileo system, Chinese Beidou systems, GLONASS, and regional systems. The book contains material on the system engineering details of GPS, European Galileo system, Chinese Beidou systems, GLONASS, Quasi-Zenith Satellite System (QZSS) and Navigation with Indian Constellation (NavIC) and investigates the integration of GNSS with other sensors and network assistance. Numéro de notice : 26395 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Recueil / ouvrage collectif Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96084 Réservation
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Table des matières Understanding GPS/GNSS... - pdf éditeurAdobe Acrobat PDFAssessment of the DORIS network monumentation / Jérôme Saunier in Advances in space research, vol 58 n° 12 (15 December 2016)
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Titre : Assessment of the DORIS network monumentation Type de document : Article/Communication Auteurs : Jérôme Saunier , Auteur
Année de publication : 2016 Article en page(s) : pp 2725 - 2741 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] DORIS
[Termes IGN] Global Geodetic Observing System
[Termes IGN] stabilitéRésumé : (auteur) Stability of the monumentation is essential for precise positioning applications to minimize velocity uncertainties and noises in the position data. In charge of the DORIS global tracking network deployment since the beginning, IGN, in consultation with CNES, designed three standard monuments compliant with the DORIS system requirements and general geodetic specifications, and suitable for various site configurations: building roofs, concrete pedestals or pillars. This paper describes the monument types in use in the DORIS network according to the current required specifications and provides a comparative assessment of the stability of the monuments over the network based on three methods: a theoretical study of the mechanical behavior of the metallic structures, a misclosure analysis taken during ground surveys and a qualitative approach taking into account different factors. This overview of the network monumentation gives new key numbers following the previous network assessment performed by Fagard (2006). Significant improvements have been made following the continuous efforts to renovate the network monumentation. These results are relevant for the Global Geodetic Observing System (GGOS) goals of measurement stability for the geodetic techniques. Today, two-thirds of the DORIS network monuments are compliant with the standards aiming at stability of 0.1 mm/y. This stability result has been measured for 16 of the 58 stations more than 10 y after its installation while monuments with more than 1 mm antenna tilts are over 10 y old when specifications were less stringent. The grading and scoring grid drawn up for each monument led to the mapping of the stability of the current DORIS network. Finally, we present a number of further actions to monitor the monument stability and provide new elements for the network monumentation assessment, exploring two different approaches: analysis of the time series and direct measurements using devices placed on each monument. Numéro de notice : A2016--186 Affiliation des auteurs : IGN (2012-2019) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2016.02.026 Date de publication en ligne : 09/03/2016 En ligne : https://doi.org/10.1016/j.asr.2016.02.026 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91822
in Advances in space research > vol 58 n° 12 (15 December 2016) . - pp 2725 - 2741[article]Is the Jason-2 DORIS oscillator also affected by the South Atlantic Anomaly? / Pascal Willis in Advances in space research, vol 58 n° 12 (15 December 2016)
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Titre : Is the Jason-2 DORIS oscillator also affected by the South Atlantic Anomaly? Type de document : Article/Communication Auteurs : Pascal Willis , Auteur ; Michael B. Heflin, Auteur ; Bruce J. Haines, Auteur ; Yoaz E. Bar-Sever, Auteur ; Willy I. Bertiger, Auteur ; Mioara Mandea, Auteur
Année de publication : 2016 Article en page(s) : pp 2617 - 2627 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] anomalie de Bouguer
[Termes IGN] Atlantique Sud
[Termes IGN] co-positionnement
[Termes IGN] données DORIS
[Termes IGN] données GPS
[Termes IGN] erreur systématique
[Termes IGN] Jason
[Termes IGN] oscillateur
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résidu
[Termes IGN] série temporelle
[Termes IGN] station permanenteRésumé : (auteur) We analyzed time series of daily DORIS and GPS station coordinate estimates derived from Precise Point Positioning (PPP). The DORIS coordinates were estimated using Jason-2 precise orbits based on GPS data only, implying that the station positions from the two techniques are expressed in the same GPS-based terrestrial reference frame. Comparisons of 3-D vectors of such co-located stations show systematic biases in position around South America when compared to local geodetic ties. We conclude that these results could be explained by a sensitivity of the Jason-2/DORIS oscillator to radiation when the satellite passes over the South Atlantic Anomaly (SAA). The effect for Jason-2 manifests mainly as an offset in station coordinates, though there is also evidence of a drift at the start of the mission that diminishes in time. This contrasts with the experience on Jason-1, wherein large, persistent drifts were observed for stations in this same (SAA) region. The spurious drift is much (∼90%) smaller for Jason-2, which may be attributable to the steps taken prior to launch to harden the oscillator. Analysis of DORIS Doppler residuals may indicate some small degradation after 2009 for these stations. Numéro de notice : A2016--178 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2016.09.015 Date de publication en ligne : 21/09/2016 En ligne : https://doi.org/10.1016/j.asr.2016.09.015 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91806
in Advances in space research > vol 58 n° 12 (15 December 2016) . - pp 2617 - 2627[article]The International DORIS Service contribution to the 2014 realization of the International Terrestrial Reference Frame / Guilhem Moreaux in Advances in space research, vol 58 n° 12 (15 December 2016)
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Titre : The International DORIS Service contribution to the 2014 realization of the International Terrestrial Reference Frame Type de document : Article/Communication Auteurs : Guilhem Moreaux, Auteur ; Franck G. Lemoine, Auteur ; Hugues Capdeville, Auteur ; Sergey P. Kuzin, Auteur ; Michiel Otten, Auteur ; Petr Štěpánek, Auteur ; Pascal Willis , Auteur ; Pascale Ferrage, Auteur
Année de publication : 2016 Article en page(s) : pp 2479 - 2504 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] DORIS
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] mouvement du pôle
[Termes IGN] positionnement par DORISRésumé : (auteur) In preparation of the 2014 realization of the International Terrestrial Reference Frame (ITRF2014), the International DORIS Service delivered to the International Earth Rotation and Reference Systems Service a set of 1140 weekly solution files including station coordinates and Earth orientation parameters, covering the time period from 1993.0 to 2015.0. The data come from eleven DORIS satellites: TOPEX/Poseidon, SPOT2, SPOT3, SPOT4, SPOT5, Envisat, Jason-1, Jason-2, Cryosat-2, Saral and HY-2A. In their processing, the six analysis centers which contributed to the DORIS combined solution used the latest time variable gravity models and estimated DORIS ground beacon frequency variations. Furthermore, all the analysis centers but one excepted included in their processing phase center variations for ground antennas. The main objective of this study is to present the combination process and to analyze the impact of the new modeling on the performance of the new combined solution. Comparisons with the IDS contribution to ITRF2008 show that (i) the application of the DORIS ground phase center variations in the data processing shifts the combined scale upward by nearly 7–11 mm and (ii) thanks to estimation of DORIS ground beacon frequency variations, the new combined solution no longer shows any scale discontinuity in early 2002 and does not present unexplained vertical discontinuities in any station position time series. However, analysis of the new series with respect to ITRF2008 exhibits a scale increase late 2011 which is not yet explained. A new DORIS Terrestrial Reference Frame was computed to evaluate the intrinsic quality of the new combined solution. That evaluation shows that the addition of data from the new missions equipped with the latest generation of DORIS receiver (Jason-2, Cryosat-2, HY-2A, Saral), results in an internal position consistency of 10 mm or better after mid-2008. Numéro de notice : A2016--175 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2015.12.021 Date de publication en ligne : 14/12/2015 En ligne : https://doi.org/10.1016/j.asr.2015.12.021 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91796
in Advances in space research > vol 58 n° 12 (15 December 2016) . - pp 2479 - 2504[article] PermalinkAssessment of the accuracy of global geodetic satellite laser ranging observations and estimated impact on ITRF scale: estimation of systematic errors in LAGEOS observations 1993–2014 / Graham Appleby in Journal of geodesy, vol 90 n° 12 (December 2016)
PermalinkComplex demodulation in monitoring earth rotation by VLBI: testing the algorithm by analysis of long periodic EOP components / Agata Wielgosz in Artificial satellites, vol 51 n° 4 (December 2016)
PermalinkDetermination of a terrestrial reference frame via Kalman filtering of very long baseline interferometry data / Benedikt Soja in Journal of geodesy, vol 90 n° 12 (December 2016)
PermalinkA drift line bias estimator: ARMA-based filter or calibration method, and its application in BDS/GPS-based attitude determination / Zhang Liang in Journal of geodesy, vol 90 n° 12 (December 2016)
PermalinkPermalinkImproved ambiguity resolution for URTK with dynamic atmosphere constraints / Weiming Tang in Journal of geodesy, vol 90 n° 12 (December 2016)
PermalinkMonitoring and prediction of precipitable water vapor using GPS data in Turkey / Kutubuddin Ansari in Journal of applied geodesy, vol 10 n° 4 (December 2016)
PermalinkVariations of total electron content over Serbia during the increased solar activity period in 2013 and 2014 / Dragan Blagojevic in Geodetski vestnik, vol 60 n° 4 (December 2016)
PermalinkModeling and assessment of triple-frequency BDS precise point positioning / Fei Guo in Journal of geodesy, vol 90 n° 11 (November 2016)
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