Descripteur
Documents disponibles dans cette catégorie (6618)
Ajouter le résultat dans votre panier
Visionner les documents numériques
Affiner la recherche Interroger des sources externes
Etendre la recherche sur niveau(x) vers le bas
A statistical characterization of the Galileo-to-GPS inter-system bias / Ciro Gioia in Journal of geodesy, vol 90 n° 11 (November 2016)
[article]
Titre : A statistical characterization of the Galileo-to-GPS inter-system bias Type de document : Article/Communication Auteurs : Ciro Gioia, Auteur ; Daniele Borio, Auteur Année de publication : 2016 Article en page(s) : pp 1279 - 1291 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] diffusion de données
[Termes IGN] données Galileo
[Termes IGN] échelle de temps
[Termes IGN] erreur systématique inter-systèmes
[Termes IGN] récepteur Galileo
[Termes IGN] récepteur GPS
[Termes IGN] signal GalileoRésumé : (Auteur) Global navigation satellite system operates using independent time scales and thus inter-system time offsets have to be determined to enable multi-constellation navigation solutions. GPS/Galileo inter-system bias and drift are evaluated here using different types of receivers: two mass market and two professional receivers. Moreover, three different approaches are considered for the inter-system bias determination: in the first one, the broadcast Galileo to GPS time offset is used to align GPS and Galileo time scales. In the second, the inter-system bias is included in the multi-constellation navigation solution and is estimated using the measurements available. Finally, an enhanced algorithm using constraints on the inter-system bias time evolution is proposed. The inter-system bias estimates obtained with the different approaches are analysed and their stability is experimentally evaluated using the Allan deviation. The impact of the inter-system bias on the position velocity time solution is also considered and the performance of the approaches analysed is evaluated in terms of standard deviation and mean errors for both horizontal and vertical components. From the experiments, it emerges that the inter-system bias is very stable and that the use of constraints, modelling the GPS/Galileo inter-system bias behaviour, significantly improves the performance of multi-constellation navigation. Numéro de notice : A2016-802 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-016-0925-6 En ligne : http://dx.doi.org/10.1007/s00190-016-0925-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82586
in Journal of geodesy > vol 90 n° 11 (November 2016) . - pp 1279 - 1291[article]Direct measurement of evapotranspiration from a forest using a superconducting gravimeter / Michel Van Camp in Geophysical research letters, vol 43 n° 19 (15 October 2016)
[article]
Titre : Direct measurement of evapotranspiration from a forest using a superconducting gravimeter Type de document : Article/Communication Auteurs : Michel Van Camp, Auteur ; Olivier de Viron, Auteur ; Gwendoline Pajot-Métivier , Auteur ; Fabien Casenave , Auteur ; Arnaud Watlet, Auteur ; Alain Dassargues, Auteur ; Marnik Vanclooster, Auteur Année de publication : 2016 Article en page(s) : pp 10225 - 10231 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Belgique
[Termes IGN] évapotranspiration
[Termes IGN] feuillu
[Termes IGN] forêt tempérée
[Termes IGN] gravimètre supraconducteur
[Termes IGN] humidité du sol
[Termes IGN] levé gravimétrique
[Termes IGN] variation diurneRésumé : (auteur) Evapotranspiration (ET) controls the flux between the land surface and the atmosphere. Assessing the ET ecosystems remains a key challenge in hydrology. We have found that the ET water mass loss can be directly inferred from continuous gravity measurements: as water evaporates and transpires from terrestrial ecosystems, the mass distribution of water decreases, changing the gravity field.
Using continuous superconducting gravity measurements, we were able to identify daily gravity changes at the level of, or smaller than 10-9 nm.s-2 (or 10-10 g) per day. This corresponds to 1.7 mm of water over an area of 50 ha. The strength of this method is its ability to enable a direct, traceable and continuous monitoring of actual ET for years at the mesoscale with a high accuracy.Numéro de notice : A2016-684 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1002/2016GL070534 Date de publication en ligne : 07/10/2016 En ligne : http://dx.doi.org/10.1002/2016GL070534 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81973
in Geophysical research letters > vol 43 n° 19 (15 October 2016) . - pp 10225 - 10231[article]Documents numériques
peut être téléchargé
Direct measurement of evapotranspiration ... - pdf éditeurAdobe Acrobat PDF Evidence for postglacial signatures in gravity gradients: A clue in lower mantle viscosity / Laurent Métivier in Earth and planetary science letters, vol 452 (October 2016)
[article]
Titre : Evidence for postglacial signatures in gravity gradients: A clue in lower mantle viscosity Type de document : Article/Communication Auteurs : Laurent Métivier , Auteur ; Lambert Caron, Auteur ; Marianne Greff-Lefftz, Auteur ; Gwendoline Pajot-Métivier , Auteur ; Luce Fleitout, Auteur ; Hélène Rouby , Auteur Année de publication : 2016 Article en page(s) : pp 146 - 156 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] Amérique du nord
[Termes IGN] anomalie de pesanteur
[Termes IGN] déformation de la croute terrestre
[Termes IGN] gradient de gravitation
[Termes IGN] manteau terrestre
[Termes IGN] paléocontinent
[Termes IGN] viscositéRésumé : (auteur) The Earth's surface was depressed under the weight of ice during the last glaciations. Glacial Isostatic Adjustment (GIA) induces the slow recession of the trough that is left after deglaciation and is responsible for a contemporary uplift rate of more than 1 cm/yr around Hudson Bay. The present-day residual depression, an indicator of still-ongoing GIA, is difficult to identify in the observed topography, which is predominantly sensitive to crustal heterogeneities. According to the most widespread GIA models, which feature a viscosity of 2–3×1021 Pa s2–3×1021 Pa s on top of the lower mantle, the trough is approximately 100 m deep and cannot explain the observed gravity anomalies across North America. These large anomalies are therefore usually attributed to subcontinental density heterogeneities in the tectosphere or to slab downwelling in the deep mantle.
Here, we use observed gravity gradients (GG) to show that the uncompensated GIA trough is four times larger than expected and that it is the main source of the North American static gravity signal. We search for the contribution to these GGs from mantle mass anomalies, which are deduced from seismic tomography and are mechanically coupled to the global mantle flow. This contribution is found to be small over Laurentia, and at least 82% of the GGs are caused by GIA. Such a contribution from GIA in these GG observations implies a viscosity that is greater than 1022 Pa s1022 Pa s in the lower mantle.
Our conclusions are a plea for GIA models with a highly viscous lower mantle, which confirm inferences from mantle dynamic models. Any change in GIA modelling has important paleoclimatological and environmental implications, encouraging scientists to re-evaluate the past ice history at a global scale. These implications, in turn, affect the contribution of bedrock uplift to the contemporaneous mass balance over Antarctica and Greenland and thus the present-day ice-melting rate as deduced from the GRACE space mission. Additionally, studies of the thermo-chemical structure of the lithosphere/crust under North America that exploit gravity or geodetic data should be corrected for a GIA model, which is not the case today.Numéro de notice : A2016-906 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.epsl.2016.07.034 Date de publication en ligne : 16/08/2016 En ligne : http://dx.doi.org/10.1016/j.epsl.2016.07.034 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83034
in Earth and planetary science letters > vol 452 (October 2016) . - pp 146 - 156[article]Design drivers and new trends for navigation message authentication schemes for GNSS systems / Gianluca Caparra in Inside GNSS, vol 11 n° 5 (September - October 2016)
[article]
Titre : Design drivers and new trends for navigation message authentication schemes for GNSS systems Type de document : Article/Communication Auteurs : Gianluca Caparra, Auteur ; Christian Wullems, Auteur ; Silvia Ceccato, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 64 - 73 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] authentification
[Termes IGN] sécurité informatique
[Termes IGN] signal GNSSRésumé : (auteur) GNSS has become a mature technology yielding reliable position, navigation and timing solutions upon which many applications are built. Its widespread adoption has turned into an incentive for malicious actions that, by exploiting GNSS vulnerabilities, aim at either disrupting or precisely modifying the PNT computation. Authenticating the GNSS signal at both the ranging and data levels is a proper way to detect and/or mitigate such threats. This article discusses the design drivers for GNSS authentication, reviews the predominant navigation message authentication proposals for a GNSS open service, and proposes a novel scheme based on the amortization of digital signatures. Numéro de notice : A2016-964 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans En ligne : http://www.insidegnss.com/node/5101 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83614
in Inside GNSS > vol 11 n° 5 (September - October 2016) . - pp 64 - 73[article]Disaster debris estimation using high-resolution polarimetric stereo-SAR / Christian N. Koyama in ISPRS Journal of photogrammetry and remote sensing, vol 120 (october 2016)
[article]
Titre : Disaster debris estimation using high-resolution polarimetric stereo-SAR Type de document : Article/Communication Auteurs : Christian N. Koyama, Auteur ; Hideomi Gokon, Auteur ; Masaru Jimbo, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 84 - 98 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] catastrophe naturelle
[Termes IGN] déchet
[Termes IGN] estimation statistique
[Termes IGN] hauteur (coordonnée)
[Termes IGN] image radar moirée
[Termes IGN] Japon
[Termes IGN] modèle stéréoscopique
[Termes IGN] séisme
[Termes IGN] volume (grandeur)Résumé : (Auteur) This paper addresses the problem of debris estimation which is one of the most important initial challenges in the wake of a disaster like the Great East Japan Earthquake and Tsunami. Reasonable estimates of the debris have to be made available to decision makers as quickly as possible. Current approaches to obtain this information are far from being optimal as they usually rely on manual interpretation of optical imagery. We have developed a novel approach for the estimation of tsunami debris pile heights and volumes for improved emergency response. The method is based on a stereo-synthetic aperture radar (stereo-SAR) approach for very high-resolution polarimetric SAR. An advanced gradient-based optical-flow estimation technique is applied for optimal image coregistration of the low-coherence non-interferometric data resulting from the illumination from opposite directions and in different polarizations. By applying model based decomposition of the coherency matrix, only the odd bounce scattering contributions are used to optimize echo time computation. The method exclusively considers the relative height differences from the top of the piles to their base to achieve a very fine resolution in height estimation. To define the base, a reference point on non-debris-covered ground surface is located adjacent to the debris pile targets by exploiting the polarimetric scattering information. The proposed technique is validated using in situ data of real tsunami debris taken on a temporary debris management site in the tsunami affected area near Sendai city, Japan. The estimated height error is smaller than 0.6 m RMSE. The good quality of derived pile heights allows for a voxel-based estimation of debris volumes with a RMSE of 1099 m3. Advantages of the proposed method are fast computation time, and robust height and volume estimation of debris piles without the need for pre-event data or auxiliary information like DEM, topographic maps or GCPs. Numéro de notice : A2016-796 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2016.08.003 En ligne : https://doi.org/10.1016/j.isprsjprs.2016.08.003 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82530
in ISPRS Journal of photogrammetry and remote sensing > vol 120 (october 2016) . - pp 84 - 98[article]Generating GPS satellite fractional cycle bias for ambiguity-fixed precise point positioning / Pan Li in GPS solutions, vol 20 n° 4 (October 2016)PermalinkLong-term soil moisture dynamics derived from GNSS interferometric reflectometry: a case study for Sutherland, South Africa / Sibylle Vey in GPS solutions, vol 20 n° 4 (October 2016)PermalinkA new ZTD model based on permanent ground-based GNSS-ZTD data / M. Ding in Survey review, vol 48 n° 351 (October 2016)PermalinkOn the significance of periodic signals in noise analysis of GPS station coordinates time series / Janusz Bogusz in GPS solutions, vol 20 n° 4 (October 2016)PermalinkOne continent, one representation / IGN France International IFI in GEO: Geoconnexion international, vol 15 n° 9 (October 2016)PermalinkOutlier detection by using fault detection and isolation techniques in geodetic networks / U.M. Durdag in Survey review, vol 48 n° 351 (October 2016)PermalinkAn adaptable equal-area pseudoconic map projection / Daniel "daan" Strebe in Cartography and Geographic Information Science, Vol 43 n° 4 (September 2016)PermalinkAutomatic rough georeferencing of multiview oblique and vertical aerial image datasets of urban scenes / Styliani Verykokou in Photogrammetric record, vol 31 n° 155 (September - November 2016)PermalinkA conventional value for the geoid reference potential W0 / L. Sánchez in Journal of geodesy, vol 90 n° 9 (September 2016)PermalinkEfficient terrestrial laser scan segmentation exploiting data structure / Hamid Mahmoudabadi in ISPRS Journal of photogrammetry and remote sensing, vol 119 (September 2016)PermalinkGalileo cycle-slip detection : How four frequencies help when the ionosphere is disturbed / Laura Van de Vyver in GPS world, vol 27 n° 9 (September 2016)PermalinkGNSS interferometric radio occultation / Manuel Martín-Neira in IEEE Transactions on geoscience and remote sensing, vol 54 n° 9 (September 2016)PermalinkIdentification of stable areas in unreferenced laser scans for deformation measurement / Daniel Wujanz in Photogrammetric record, vol 31 n° 155 (September - November 2016)PermalinkIndispensables encrages de l'altimétrie / Michel Kasser in Géomètre, n° 2139 (septembre 2016)PermalinkMonitoring the oldest datum / John Stenmark in GEO: Geoconnexion international, vol 15 n° 8 (September 2016)PermalinkA novel methodology for identifying environmental exposures using GPS data / Andreea Cetateanu in International journal of geographical information science IJGIS, vol 30 n° 9-10 (September - October 2016)PermalinkReal-time cycle-slip detection and repair for BeiDou triple-frequency undifferenced observations / Y.-F. Yao in Survey review, vol 48 n° 350 (September 2016)PermalinkRecovery of cadastral boundaries with GNSS equipment / A. Cina in Survey review, vol 48 n° 350 (September 2016)PermalinkSome equal-area, conformal and conventional map projections: a tutorial review / Ebrahim Ghaderpour in Journal of applied geodesy, vol 10 n° 3 (September 2016)PermalinkTaking correlations in GPS least squares adjustments into account with a diagonal covariance matrix / Gaël Kermarrec in Journal of geodesy, vol 90 n° 9 (September 2016)PermalinkThe SMITSWAM method of datum transformations consisting of Standard Molodensky in two stages with applied misclosures / Andrew Carey Ruffhead in Survey review, vol 48 n° 350 (September 2016)PermalinkTopographic gravitational potential up to second-order derivatives: an examination of approximation errors caused by rock-equivalent topography (RET) / Michael Kuhns in Journal of geodesy, vol 90 n° 9 (September 2016)PermalinkUse of a GPS-derived troposphere model to improve InSAR deformation estimates in the San Gabriel Valley, California / Nicolas Houlié in IEEE Transactions on geoscience and remote sensing, vol 54 n° 9 (September 2016)PermalinkUse of the gyrotheodolite in underground networks of long high-speed railway tunnels / J. Velasco-Gómez, in Survey review, vol 48 n° 350 (September 2016)PermalinkA new method to improve the performance of multi-GNSS pseudorange positioning in signal-degraded environment / Hui Liu in Advances in space research, vol 58 n° 4 (August 2016)PermalinkAutomatic extraction of road networks from GPS traces / Jia Qiu in Photogrammetric Engineering & Remote Sensing, PERS, vol 82 n° 8 (August 2016)PermalinkBimodal pattern of seismicity detected at the ocean margin of an Antarctic ice shelf / Denis Lombardi in Geophysical journal international, vol 206 n° 2 (August 2016)PermalinkEstimation of satellite antenna phase center offsets for Galileo / Peter Steigenberger in Journal of geodesy, vol 90 n° 8 (August 2016)PermalinkGalileo and the Brexit effect : Tension grows over the public regulated service / Tim Reynolds in GPS world, vol 27 n° 8 (August 2016)PermalinkA geometry-free and ionosphere-free multipath mitigation method for BDS three-frequency ambiguity resolution / Dezhong Chen in Journal of geodesy, vol 90 n° 8 (August 2016)PermalinkInterference mitigation in the E5A Galileo band using an open-source simulator / Diego Alonso in Inside GNSS, vol 11 n° 4 (July - August 2016)PermalinkA new computerized ionosphere tomography model using the mapping function and an application to the study of seismic-ionosphere disturbance / Jian Kong in Journal of geodesy, vol 90 n° 8 (August 2016)PermalinkBenefits of the third frequency signal on cycle slip correction / Xiaohong Zhang in GPS solutions, vol 20 n° 3 (July 2016)PermalinkA closed-form formula to calculate geometric dilution of precision (GDOP) for multi-GNSS constellations / Yunlong Teng in GPS solutions, vol 20 n° 3 (July 2016)PermalinkA comparative analysis of measurement noise and multipath for four constellations: GPS, BeiDou, GLONASS and Galileo / Changsheng Cai in Survey review, vol 48 n° 349 (July 2016)PermalinkComputation and visualisation of the accuracy of old maps using differential distortion analysis / Manuel Claeys Boùùaert in International journal of geographical information science IJGIS, vol 30 n° 7- 8 (July - August 2016)PermalinkDirection-of-arrival estimation of VHF signals recorded on the international space station and simultaneous observations of optical lightning / Hiroshi Kikuchi in IEEE Transactions on geoscience and remote sensing, vol 54 n° 7 (July 2016)PermalinkFast computation of general forward gravitation problems / Fabien Casenave in Journal of geodesy, vol 90 n° 7 (July 2016)PermalinkIdentifying a low-frequency oscillation in Galileo IOV pseudorange rates / Daniele Borio in GPS solutions, vol 20 n° 3 (July 2016)PermalinkImproved PPP performance in regional networks / Stefano Gandolfi in GPS solutions, vol 20 n° 3 (July 2016)PermalinkPermalinkRobust approach for recovery of rigorous sensor model using rational function model / Wen-chao Huang in IEEE Transactions on geoscience and remote sensing, vol 54 n° 7 (July 2016)PermalinkStochastic modeling of triple-frequency BeiDou signals: estimation, assessment and impact analysis / Bofeng Li in Journal of geodesy, vol 90 n° 7 (July 2016)PermalinkThe African geodetic reference frame / Richard Wonnacott in GIM international, vol 30 n° 7 (July 2016)PermalinkPermalink