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EMVS : Event-based Multi-View Stereo : 3D reconstruction with an event camera in real-time / Henri Rebecq in International journal of computer vision, vol 126 n° 12 (December 2018)
[article]
Titre : EMVS : Event-based Multi-View Stereo : 3D reconstruction with an event camera in real-time Type de document : Article/Communication Auteurs : Henri Rebecq, Auteur ; Guillermo Gallego, Auteur ; Elias Mueggler, Auteur ; Davide Scaramuzza, Auteur Année de publication : 2018 Article en page(s) : pp 1394 - 1414 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] caméra d'événement
[Termes IGN] carte de profondeur
[Termes IGN] luminance lumineuse
[Termes IGN] reconstruction 3D
[Termes IGN] temps réelRésumé : (Auteur) Event cameras are bio-inspired vision sensors that output pixel-level brightness changes instead of standard intensity frames. They offer significant advantages over standard cameras, namely a very high dynamic range, no motion blur, and a latency in the order of microseconds. However, because the output is composed of a sequence of asynchronous events rather than actual intensity images, traditional vision algorithms cannot be applied, so that a paradigm shift is needed. We introduce the problem of event-based multi-view stereo (EMVS) for event cameras and propose a solution to it. Unlike traditional MVS methods, which address the problem of estimating dense 3D structure from a set of known viewpoints, EMVS estimates semi-dense 3D structure from an event camera with known trajectory. Our EMVS solution elegantly exploits two inherent properties of an event camera: (1) its ability to respond to scene edges—which naturally provide semi-dense geometric information without any pre-processing operation—and (2) the fact that it provides continuous measurements as the sensor moves. Despite its simplicity (it can be implemented in a few lines of code), our algorithm is able to produce accurate, semi-dense depth maps, without requiring any explicit data association or intensity estimation. We successfully validate our method on both synthetic and real data. Our method is computationally very efficient and runs in real-time on a CPU. Numéro de notice : A2018-597 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s11263-017-1050-6 Date de publication en ligne : 07/11/2017 En ligne : https://doi.org/10.1007/s11263-017-1050-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92524
in International journal of computer vision > vol 126 n° 12 (December 2018) . - pp 1394 - 1414[article]Enhanced local ionosphere model for multi-constellations single frequency precise point positioning applications: Egyptian case study / Emad El Manaily in Artificial satellites, vol 53 n° 4 (December 2018)
[article]
Titre : Enhanced local ionosphere model for multi-constellations single frequency precise point positioning applications: Egyptian case study Type de document : Article/Communication Auteurs : Emad El Manaily, Auteur ; Mahmoud Abd Rabbou, Auteur ; Adel El-Shazly, Auteur ; Moustafa Baraka, Auteur Année de publication : 2018 Article en page(s) : pp.141 – 157 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] constellation GNSS
[Termes IGN] Egypte
[Termes IGN] international GPS service for geodynamics
[Termes IGN] Le Caire
[Termes IGN] modèle ionosphérique
[Termes IGN] occultation du signal
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] récepteur monofréquence
[Termes IGN] retard ionosphèrique
[Termes IGN] signal GNSSRésumé : (auteur) The positioning accuracy of single frequency precise point positioning (SFPPP) attributes mainly to the ionosphere error, which strongly affects GNSS signals. When GNSS signals pass through the various ionosphere layers, they will be bent and their speed will be changed due to dispersive nature of ionosphere. To correct the ionosphere error, it is common to use Klobuchar ionosphere model or Global Ionosphere Maps (GIM). However, Klobuchar can deal with only about 50% of the Ionosphere effect and global Ionosphere maps are often inadequate to describe detailed features of local ionosphere because of limited precision and resolution. In this paper, an enhanced local ionosphere model was developed relying on modeling of measurements from a dense Egyptian permanent tracking GNSS network in order to achieve high precision ionosphere delay correction. The performance of the developed enhanced Egyptian ionosphere model (EIM) was verified through multi-constellations SFPPP accuracy for static and kinematic modes. For static mode, 24 hours multi-constellations datasets collected at three selected stations, Alexandria, Cairo, and Aswan, in Egypt on February 27, 2017, to investigate the performance of the developed local ionospheric model in comparison with the Klobuchar, GIM and ionosphere free models. After session time of half an hour, the results show that the performance of static SFPPP based on the developed Egyptian ionospheric map (EIM) achieved a comparable accuracy WRT using ionosphere free model. While using EIM, achieved an improvements of (38%, 28%, and 42%) and (32%, 10%, and 37%) for accuracy of latitude, longitude, and altitude in comparison with using Klobuchar and GIM models, respectively For kinematic mode, datasets of 2 hours of observations with 1 second sampling rate were logged during vehicular test; the test was carried out on the ring road of the city of Cairo, Egypt, on September 16, 2017. After half an hour of kinematic SFPPP data-processing, the performance of using Egyptian ionospheric map (EIM) for ionosphere delay correction, achieved an improvements of three dimension coordinates of (83%, 47%, and 62%) and (57%, 65%, and 21%) with respect to using Klobuchar model and GIM model, respectively. Numéro de notice : A2018-606 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.2478/arsa-2018-0011 Date de publication en ligne : 11/01/2019 En ligne : https://content.sciendo.com/view/journals/arsa/53/4/article-p141.xml Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92627
in Artificial satellites > vol 53 n° 4 (December 2018) . - pp.141 – 157[article]Documents numériques
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Enhanced local ionosphere model ... - pdf éditeurAdobe Acrobat PDF Performance analysis of PPP positioning method by using IGS real-time service / Tatjana Kuzmić in Geodetski vestnik, vol 62 n° 4 (December 2018 - February 2019)
[article]
Titre : Performance analysis of PPP positioning method by using IGS real-time service Type de document : Article/Communication Auteurs : Tatjana Kuzmić, Auteur ; Vladimir Bulatović, Auteur Année de publication : 2018 Article en page(s) : pp 604 - 618 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] horloge du récepteur
[Termes IGN] international GPS service for geodynamics
[Termes IGN] modèle mathématique
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] retard troposphérique
[Termes IGN] Serbie
[Termes IGN] site web
[Termes IGN] temps de convergence
[Termes IGN] temps réel
[Termes IGN] test de performanceRésumé : (auteur) There are many positioning methods based on the usage of GNSS (Global Navigation Satellite System). They are classified according to the accuracy they can achieve, the time needed to obtain fixed solutions and the concept of positioning - number of used receivers, type of measurement, type of GNSS system, etc. One of the most important ways to do this is PPP (Precise Point Positioning) method, primarily because of its simplicity and cost-effectiveness. The paper describes PPP positioning method, its advantages and limitations, as well as the errors that can occur. It also provides an analysis of the performance of PPP method - precision, convergence time, loss of data reception, repeatability of positioning results and accuracy based on three measurement series in duration of 4 hours each, conducted on different days. By comparing the obtained coordinates with reference ones determined by AUSPOS web service, it can be concluded that the difference between these two sets of coordinates varies from 1 cm to 7 cm, while the accuracy of measured height is lower and the difference varies from 7 cm to 20 cm. Numéro de notice : A2019-014 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.15292/geodetski-vestnik.2018.04.604-618 Date de publication en ligne : 19/11/2018 En ligne : http://doi.org/10.15292/geodetski-vestnik.2018.04.604-618 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91618
in Geodetski vestnik > vol 62 n° 4 (December 2018 - February 2019) . - pp 604 - 618[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 139-2018041 RAB Revue Centre de documentation En réserve L003 Disponible Polarimetric radar vegetation index for biomass estimation in desert fringe ecosystems / Jisung Geba Chang in IEEE Transactions on geoscience and remote sensing, vol 56 n° 12 (December 2018)
[article]
Titre : Polarimetric radar vegetation index for biomass estimation in desert fringe ecosystems Type de document : Article/Communication Auteurs : Jisung Geba Chang, Auteur ; Maxim Shoshany, Auteur ; Yisok Oh, Auteur Année de publication : 2018 Article en page(s) : pp 7102 - 7108 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] allométrie
[Termes IGN] bande C
[Termes IGN] bande L
[Termes IGN] bassin méditerranéen
[Termes IGN] biomasse
[Termes IGN] carte de la végétation
[Termes IGN] coefficient de rétrodiffusion
[Termes IGN] données de terrain
[Termes IGN] image ALOS-PALSAR
[Termes IGN] image Sentinel-SAR
[Termes IGN] indice de végétation
[Termes IGN] polarimétrie radar
[Termes IGN] zone aride
[Termes IGN] zone semi-arideRésumé : (auteur) Biomass estimation of eastern Mediterranean shrublands was investigated using PALSAR full- and dual-polarization L-band and Sentinel-1 dual-polarization C-band data. First, we conducted an empirical assessment of single and multiple regressions between polarized backscattering coefficients and shrubland biomass distribution along the climatic gradient between semiarid and arid regions. We then found that the PALSAR L-band HV-polarized backscattering coefficient has higher biomass information content than Sentinel-1 C-band data. Based on a theoretical volume scattering model and a semiempirical model, we propose a new polarimetric radar vegetation index (PRVI) that utilizes the degree of polarization and the cross-polarized backscattering coefficient. The relationship between the new index and the biomass was assessed with reference to normalized difference vegetation index-based biomass estimates calculated using Landsat imagery. The PRVI was found to have higher correlation with biomass compared with other radar polarization parameters, in general, and an existing radar vegetation index (RVI), in particular. Assessment of PRVI-based biomass predictions compared with allometric data extracted from air photographs, Lidar, and field data for 67 sites across the desert fringe zone indicated moderate performance with an RMSE of 0.329 kg/m 2 , while an RVI-based biomass estimation had an RMSE of 0.439 kg/m². Numéro de notice : A2018-553 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2018.2848285 Date de publication en ligne : 03/07/2018 En ligne : http://dx.doi.org/10.1109/TGRS.2018.2848285 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91659
in IEEE Transactions on geoscience and remote sensing > vol 56 n° 12 (December 2018) . - pp 7102 - 7108[article]Polarization orientation angle and polarimetric SAR scattering characteristics of steep terrain / Jong-Sen Lee in IEEE Transactions on geoscience and remote sensing, vol 56 n° 12 (December 2018)
[article]
Titre : Polarization orientation angle and polarimetric SAR scattering characteristics of steep terrain Type de document : Article/Communication Auteurs : Jong-Sen Lee, Auteur ; Thomas L. Ainsworth, Auteur ; Yanting Wang, Auteur Année de publication : 2018 Article en page(s) : pp 7272 - 7281 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] angle de visée
[Termes IGN] bande C
[Termes IGN] bande L
[Termes IGN] constante diélectrique
[Termes IGN] données polarimétriques
[Termes IGN] escarpement
[Termes IGN] humidité du sol
[Termes IGN] image radar moirée
[Termes IGN] image TOPSAR
[Termes IGN] modèle de diffusion du rayonnement
[Termes IGN] montagne
[Termes IGN] pente
[Termes IGN] polarimétrie radar
[Termes IGN] polarisation croisée
[Termes IGN] réflectance spectrale
[Termes IGN] rétrodiffusion de Bragg
[Termes IGN] teneur en eau de la végétationRésumé : (auteur) Polarization orientation angle (POA) is an important parameter of polarimetric radar scattering from slopes in mountainous region. It is known that surface tilted in azimuth direction and buildings not aligned in the along-track direction induce polarization orientation shifts. Earlier research has established orientation angle as a function of radar imaging geometry and surface slopes, and that POA estimation can be derived from polarimetric radar data using circular polarization. Besides these, polarimetric scattering from steep slopes and its relation to POA remain not well understood. In this paper, we address these issues by adopting a tilted surface model based on Bragg scattering. We have found that, as the azimuthal slope increases, |VV| decreases at a faster rate than |HH|, they become equal, when POA is ±45°, and |HH| > |VV| afterward. In other words, the Pauli component, |HH-VV| reduced to zero at POA = ± 45°, and the typical Bragg scattering characteristics of |VV| > |HH| does not apply when steep slope is present inducing |POA| > 45°. Furthermore, the cross-pol |HV| does not always increase with azimuth slope but also reaches a maximum then decreases to zero. In addition, we investigate the effect of soil moisture on polarimetric SAR (PolSAR) scattering characteristics of steep terrain and the effect of vegetation over surface on POA estimation. The latter is demonstrated with NASA/JPL TOPSAR L-band PolSAR data and C-band InSAR data. Another significance of this paper is that it provides a direct and rigorous derivation of POA equations. The earlier version was derived from a different concept. Numéro de notice : A2018-557 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2018.2849931 Date de publication en ligne : 01/08/2018 En ligne : http://dx.doi.org/10.1109/TGRS.2018.2849931 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91662
in IEEE Transactions on geoscience and remote sensing > vol 56 n° 12 (December 2018) . - pp 7272 - 7281[article]Potential of Sentinel-1 data for monitoring temperate mixed forest phenology / Pierre-Louis Frison in Remote sensing, vol 10 n° 12 (December 2018)PermalinkSeparating the influence of vegetation changes in polarimetric differential SAR interferometry / Virginia Brancato in IEEE Transactions on geoscience and remote sensing, vol 56 n° 12 (December 2018)PermalinkSuper-resolution of Sentinel-2 images : Learning a globally applicable deep neural network / Charis Lanaras in ISPRS Journal of photogrammetry and remote sensing, vol 146 (December 2018)PermalinkThe influence of artificial illumination of invar levelling rods / Štefan Rákay in Geodetski vestnik, vol 62 n° 4 (December 2018 - February 2019)PermalinkApplication of Landsat-8 and ASTER satellite remote sensing data for porphyry copper exploration: a case study from Shahr-e-Babak, Kerman, south of Iran / Morteza Safari in Geocarto international, vol 33 n° 11 (November 2018)PermalinkReal-Time Precise Point Positioning (RTPPP) with raw observations and its application in real-time regional ionospheric VTEC modeling / Teng Liu in Journal of geodesy, vol 92 n° 11 (November 2018)PermalinkEvaluation of three ionospheric delay computation methods for ground-based GNSS receivers / Liang Chen in GPS solutions, vol 22 n° 4 (October 2018)PermalinkMethods for quantification of systematic distance deviations under incidence angle with scanning total stations / Miriam Zámečníková in ISPRS Journal of photogrammetry and remote sensing, vol 144 (October 2018)PermalinkObject-based crop classification using multi-temporal SPOT-5 imagery and textural features with a Random Forest classifier / Huanxue Zhang in Geocarto international, vol 33 n° 10 (October 2018)PermalinkPPPH : a MATLAB-based software for multi-GNSS precise point positioning analysis / Berkay Bahadur in GPS solutions, vol 22 n° 4 (October 2018)PermalinkAssessment of local GNSS baselines at co-location sites / Iván Herrera Pinzón in Journal of geodesy, vol 92 n° 9 (September 2018)PermalinkEstimation of winter wheat crop growth parameters using time series Sentinel-1A SAR data / P. Kumar in Geocarto international, vol 33 n° 9 (September 2018)PermalinkResearch on the estimation model of vegetation water content in halophyte leaves based on the newly developed vegetation indices / Zhe Li in Photogrammetric Engineering & Remote Sensing, PERS, vol 84 n° 9 (September 2018)PermalinkVisible + Near Infrared spectroscopy as taxonomic tool for identifying birch species / Mulualem Tigabu in Silva fennica, vol 52 n° 4 (September 2018)PermalinkICARE-VEG: A 3D physics-based atmospheric correction method for tree shadows in urban areas / Karine R.M. Adeline in ISPRS Journal of photogrammetry and remote sensing, vol 142 (August 2018)PermalinkMulti-scale assessment of invasive plant species diversity using Pléiades 1A, RapidEye and Landsat-8 data / Siddhartha Khare in Geocarto international, vol 33 n° 7 (July 2018)PermalinkPrecise orbit determination of the Sentinel-3A altimetry satellite using ambiguity-fixed GPS carrier phase observations / Oliver Montenbruck in Journal of geodesy, vol 92 n° 7 (July 2018)PermalinkThe impact of solid Earth-tide model error on tropospheric zenith delay estimates and GPS coordinate time series / Fei Li in Survey review, vol 50 n° 361 (July 2018)PermalinkA two-stage tropospheric correction model combining data from GNSS and numerical weather model / Jan Douša in GPS solutions, vol 22 n° 3 (July 2018)PermalinkConnecting infrared spectra with plant traits to identify species / Maria F. Buitrago in ISPRS Journal of photogrammetry and remote sensing, vol 139 (May 2018)Permalink