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Robust determination of station positions and Earth orientation parameters by VLBI intra-technique combination / S. Böckmann (2012)
Titre : Robust determination of station positions and Earth orientation parameters by VLBI intra-technique combination Type de document : Thèse/HDR Auteurs : S. Böckmann, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2012 Collection : DGK - C Sous-collection : Dissertationen num. 684 Importance : 70 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-5096-9 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] analyse combinatoire (maths)
[Termes IGN] données ITGB
[Termes IGN] interférométrie à très grande base
[Termes IGN] méthode robuste
[Termes IGN] orientation de la Terre
[Termes IGN] valeur aberranteRésumé : (Auteur) In this thesis, it is shown that combining contributions of different VLBI analysis centers, a so called intra-technique combination, improves the robustness and stability of the final VLBI results. For this purpose, a refined combination method has been developed which is in many theoretical and practical aspects superior to combination approaches currently used for comparable geodetic combination tasks. For example, datum-free normal equation systems are used as input, which ensure that the contributions are not deformed by any constraints at all, and the same underlying terrestrial reference frame can be applied during the combination process. Furthermore, a statistically rigorous variance component estimation approach for the relative weighting of the contributions is used. The combination process implies detailed comparisons and analyses of the individual ACs' contributions. From these, as one of the outcomes of this thesis, several systematic differences between the individual contributions were detected and eliminated. The adherence to standards was considerably improved. The combination process itself reduces the "analyst's noise" and damps the impact of outliers. Validations with independent results of other space-geodetic techniques confirm a benefit of up to 15% more accurate results than from individual solutions. Another aspect of this thesis is the general problem of any intra-technique combination, the correlations between the individual contributions. So far, the contributions of different ACs are always treated as independent data sets, although they have been derived from virtually the same set of original observations. It is shown that correlations between the individual ACs' contributions can be determined and rigorously taken in account during the combination process if the combination is performed directly on the level of the observation equations, instead on the level of normal equation systems. The main effect of considering these correlations is that the formal errors of the estimated combined parameters are considerably more realistic, but the parameters as such remain unchanged within their formal errors. Numéro de notice : 14620 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère DOI : sans En ligne : https://nbn-resolving.org/urn:nbn:de:hbz:5N-23152 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=62671
Titre : Dimensionality based scale selection in 3d Lidar point clouds Type de document : Article/Communication Auteurs : Jérôme Demantké , Auteur ; Clément Mallet , Auteur ; Nicolas David , Auteur ; Bruno Vallet , Auteur Editeur : International Society for Photogrammetry and Remote Sensing ISPRS Année de publication : 2011 Collection : International Archives of Photogrammetry and Remote Sensing, ISSN 0252-8231 num. XXXVIII-5 Projets : 1-Pas de projet / Conférence : ISPRS 2011, Workshop Laser Scanning 29/08/2011 31/08/2011 Calgary Canada OA ISPRS Archives Importance : 6 p. Format : 21 x 30 cm Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] analyse en composantes principales
[Termes IGN] analyse multiéchelle
[Termes IGN] méthode robuste
[Termes IGN] semis de points
[Termes IGN] tenseur
[Termes IGN] valeur propre
[Termes IGN] voisinage (relation topologique)Résumé : (Auteur) This paper presents a multi-scale method that computes robust geometric features on lidar point clouds in order to retrieve the optimal neighborhood size for each point. Three dimensionality features are calculated on spherical neighborhoods at various radius sizes. Based on combinations of the eigenvalues of the local structure tensor, they describe the shape of the neighborhood, indicating whether the local geometry is more linear (1D), planar (2D) or volumetric (3D). Two radius-selection criteria have been tested and compared for finding automatically the optimal neighborhood radius for each point. Besides, such procedure allows a dimensionality labelling, giving significant hints for classification and segmentation purposes. The method is successfully applied to 3D point clouds from airborne, terrestrial, and mobile mapping systems since no a priori knowledge on the distribution of the 3D points is required. Extracted dimensionality features and labellings are then favorably compared to those computed from constant size neighborhoods. Numéro de notice : C2011-041 Affiliation des auteurs : MATIS (1993-2011) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.5194/isprsarchives-XXXVIII-5-W12-97-2011 Date de publication en ligne : 03/09/2012 En ligne : http://dx.doi.org/10.5194/isprsarchives-XXXVIII-5-W12-97-2011 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=64320 Documents numériques
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14254_ctap_laser_scanning_2011_mallet.pdfAdobe Acrobat PDF A featureless approach to 3D polyhedral building modeling from aerial images / Karim Hammoudi in Sensors, vol 11 n° 1 (January 2011)
[article]
Titre : A featureless approach to 3D polyhedral building modeling from aerial images Type de document : Article/Communication Auteurs : Karim Hammoudi , Auteur ; Fadi Dornaika , Auteur Année de publication : 2011 Article en page(s) : pp 228 - 259 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] image aérienne
[Termes IGN] luminance lumineuse
[Termes IGN] mesure de similitude
[Termes IGN] méthode robuste
[Termes IGN] orthoimage
[Termes IGN] reconstruction 3D du bâtiRésumé : (auteur) This paper presents a model-based approach for reconstructing 3D polyhedral building models from aerial images. The proposed approach exploits some geometric and photometric properties resulting from the perspective projection of planar structures. Data are provided by calibrated aerial images. The novelty of the approach lies in its featurelessness and in its use of direct optimization based on image rawbrightness. The proposed framework avoids feature extraction and matching. The 3D polyhedral model is directly estimated by optimizing an objective function that combines an image-based dissimilarity measure and a gradient score over several aerial images. The optimization process is carried out by the Differential Evolution algorithm. The proposed approach is intended to provide more accurate 3D reconstruction than feature-based approaches. Fast 3D model rectification and updating can take advantage of the proposed method. Several results and evaluations of performance from real and synthetic images show the feasibility and robustness of the proposed approach. Numéro de notice : A2011-611 Affiliation des auteurs : MATIS+Ext (1993-2011) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/s110100228 Date de publication en ligne : 28/12/2010 En ligne : https://doi.org/10.3390/s110100228 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91711
in Sensors > vol 11 n° 1 (January 2011) . - pp 228 - 259[article]Orthorectification of VHR optical satellite data exploiting the geometric accuracy of TerraSAR-X data / Peter Reinartz in ISPRS Journal of photogrammetry and remote sensing, vol 66 n° 1 (January - February 2011)
[article]
Titre : Orthorectification of VHR optical satellite data exploiting the geometric accuracy of TerraSAR-X data Type de document : Article/Communication Auteurs : Peter Reinartz, Auteur ; R. Muller, Auteur ; P. Schwind, Auteur ; et al., Auteur Année de publication : 2011 Article en page(s) : pp 124 - 132 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image mixte
[Termes IGN] appariement d'images
[Termes IGN] erreur moyenne quadratique
[Termes IGN] image ALOS-PRISM
[Termes IGN] image Ikonos
[Termes IGN] image optique
[Termes IGN] image radar
[Termes IGN] image TerraSAR-X
[Termes IGN] méthode robuste
[Termes IGN] modèle par fonctions rationnelles
[Termes IGN] orientation du capteur
[Termes IGN] orthorectification
[Termes IGN] point d'appui
[Termes IGN] précision géométrique (imagerie)
[Termes IGN] zone urbaineRésumé : (Auteur) Orthorectification of satellite data is one of the most important pre-processing steps for application oriented evaluations and for image data input into Geographic Information Systems. Although high- and very high-resolution optical data can be rectified without ground control points (GCPs) using an underlying digital elevation model (DEM) to positional root mean square errors (RMSEs) between 3 m and several hundred meters (depending on the satellite), there is still need for ground control with higher precision to reach lower RMSE values for the orthoimages. The very high geometric accuracy of geocoded data of the TerraSAR-X satellite has been shown in several investigations. This is due to the fact that the SAR antenna measures distances which are mainly dependent on the terrain height and the position of the satellite. The latter can be measured with high precision, whereas the satellite attitude need not be known exactly. If the used DEM is of high accuracy, the resulting geocoded SAR data are very precise in their geolocation. This precision can be exploited to improve the orientation knowledge and thereby the geometric accuracy of the rectified optical satellite data. The challenge is to match two kinds of image data, which exhibit very different geometric and radiometric properties. Simple correlation techniques do not work and the goal is to develop a robust method which works even for urban areas, including radar shadows, layover and foreshortening effects. First the optical data have to be rectified with the available interior and exterior orientation data or using rational polynomial coefficients (RPCs). From this approximation, the technique used is the measurement of small identical areas in the optical and radar images by automatic image matching, using a newly developed adapted mutual information procedure followed by an estimation of correction terms for the exterior orientation or the RPC coefficients. The matching areas are selected randomly from a regular grid covering the whole imagery. By adjustment calculations, parameters from falsely matched areas can be eliminated and optimal improvement parameters are found. The original optical data are orthorectified again using the delivered metadata together with these corrections and the available DEM. As proof of method the orthorectified data from IKONOS and ALOS-PRISM sensors are compared with conventional ground control information from high-precision orthoimage maps of the German Cartographic Survey. The results show that this method is robust, even for urban areas. Although the resulting RMSE values are in the order of 2–6 m, the advantage is that this result can be reached even for optical sensors which do not exhibit low RMSE values without using manual GCP measurements. Numéro de notice : A2011-017 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2010.10.003 En ligne : https://doi.org/10.1016/j.isprsjprs.2010.10.003 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30799
in ISPRS Journal of photogrammetry and remote sensing > vol 66 n° 1 (January - February 2011) . - pp 124 - 132[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2011011 SL Revue Centre de documentation Revues en salle Disponible Orientation relative à partir de 3 points homologues et de la direction verticale : Une approche directe / Mahzad Kalantari in Traitement du signal, vol 27 n° 3 (2010-3)
[article]
Titre : Orientation relative à partir de 3 points homologues et de la direction verticale : Une approche directe Titre original : Relative orientation using 3 points and the vertical direction. A direct approach Type de document : Article/Communication Auteurs : Mahzad Kalantari , Auteur ; Amir Hashemi, Auteur ; Franck Jung , Auteur ; Jean Pierre Guedon, Auteur Année de publication : 2010 Article en page(s) : pp 325 - 348 Note générale : Bibliographie Langues : Français (fre) Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] bases de Gröbner
[Termes IGN] coplanarité
[Termes IGN] couple stéréoscopique
[Termes IGN] méthode robuste
[Termes IGN] orientation relative
[Termes IGN] points homologues
[Termes IGN] verticaleRésumé : (Auteur) Cet article propose une nouvelle méthode pour trouver l’orientation relative entre deux images, en utilisant trois points homologues et l’identification de la direction verticale dans les images. La direction verticale peut être déterminée de deux façons : 1- avec une mesure physique directe comme par exemple une centrale inertielle (IMU), 2- l’utilisation du point de fuite correspondant aux verticales. Cette connaissance de la direction verticale résout deux inconnues parmi les trois paramètres de la rotation relative, de sorte que seulement trois points homologues sont nécessaires dans les deux images. En réécrivant les équations de coplanarité, on parvient à une solution beaucoup plus simple. La résolution des inconnues restantes est exécutée par une méthode algébrique qui utilise les bases de Gröbner. Les éléments nécessaires pour construire une solution algébrique spécifique sont donnés dans cet article, en tenant compte d’une mise en oeuvre temps réel. Les résultats sur des données synthétiques puis sur des données réelles montrent l’efficacité de cette méthode. Numéro de notice : A2010-641 Affiliation des auteurs : LGA+Ext (2009-2011) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueNat DOI : 10.3166/ts.27.325-348 Date de publication en ligne : 01/06/2010 En ligne : https://doi.org/10.3166/ts.27.325-348 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90706
in Traitement du signal > vol 27 n° 3 (2010-3) . - pp 325 - 348[article]Robust Kalman filtering with constraints: a case study for integrated navigation / Y. Yang in Journal of geodesy, vol 84 n° 6 (June 2010)PermalinkPermalinkImproving GPS localization with vision and inertial sensing / A. Fakih in Geomatica, vol 63 n° 4 (December 2009)PermalinkPrecise, automatic and fast method for vanishing point detection / Mahzad Kalantari in Photogrammetric record, vol 24 n° 127 (September - November 2009)PermalinkPermalinkInstantaneous 3D motion from image derivatives using the Least Trimmed Square regression / Fadi Dornaika in Pattern recognition letters, vol 30 n° 5 (April 2009)PermalinkAnalyse exploratoire des effets de support spatial et de robustesse statistique sur la fiabilité de la mesure de la (bio)diversité / Didier Josselin in Photo interprétation, European journal of applied remote sensing, vol 45 n° 1 (mars 2009)PermalinkAutomatic estimation of fine terrain models from multiple high-resolution satellite images / Nicolas Champion (2009)PermalinkAutomatic revision of 2D building databases from high resolution satellite imagery : a 3D photogrammetric approach / Nicolas Champion (2009)PermalinkExtracting composite cartographic area features in low-quality maps / S. Leyk in Cartography and Geographic Information Science, vol 36 n° 1 (January 2009)Permalink