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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 Road safety evaluation through automatic extraction of road horizontal alignments from Mobile LiDAR System and inductive reasoning based on a decision tree / José Antonio Martin-Jimenez in ISPRS Journal of photogrammetry and remote sensing, vol 146 (December 2018)
[article]
Titre : Road safety evaluation through automatic extraction of road horizontal alignments from Mobile LiDAR System and inductive reasoning based on a decision tree Type de document : Article/Communication Auteurs : José Antonio Martin-Jimenez, Auteur ; Santiago Zazo, Auteur ; José Juan Arranz Justel, Auteur ; et al., Auteur Année de publication : 2018 Article en page(s) : pp 334 - 346 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] accident de la route
[Termes IGN] arbre de décision
[Termes IGN] cohérence géométrique
[Termes IGN] données GNSS
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] Espagne
[Termes IGN] extraction du réseau routier
[Termes IGN] indice de risque
[Termes IGN] lidar mobile
[Termes IGN] raisonnement
[Termes IGN] sécurité routière
[Termes IGN] segmentation
[Termes IGN] semis de points
[Termes IGN] triangulation de DelaunayRésumé : (auteur) Safe roads are a necessity for any society because of the high social costs of traffic accidents. This challenge is addressed by a novel methodology that allows us to evaluate road safety from Mobile LiDAR System data, taking advantage of the road alignment due to its influence on the accident rate. Automation is obtained through an inductive reasoning process based on a decision tree that provides a potential risk assessment. To achieve this, a 3D point cloud is classified by an iterative and incremental algorithm based on a 2.5D and 3D Delaunay triangulation, which apply different algorithms sequentially. Next, an automatic extraction process of road horizontal alignment parameters is developed to obtain geometric consistency indexes, based on a joint triple stability criterion. Likewise, this work aims to provide a powerful and effective preventive and/or predictive tool for road safety inspections. The proposed methodology was implemented on three stretches of Spanish roads, each with different traffic conditions that represent the most common road types. The developed methodology was successfully validated through as-built road projects, which were considered as “ground truth.” Numéro de notice : A2018-541 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2018.10.004 Date de publication en ligne : 21/10/2018 En ligne : https://doi.org/10.1016/j.isprsjprs.2018.10.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91565
in ISPRS Journal of photogrammetry and remote sensing > vol 146 (December 2018) . - pp 334 - 346[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2018131 RAB Revue Centre de documentation En réserve L003 Disponible 081-2018133 DEP-EXM Revue LASTIG Dépôt en unité Exclu du prêt 081-2018132 DEP-EAF Revue Nancy Dépôt en unité Exclu du prêt Global IWV trends and variability in atmospheric reanalyses and GPS observations / Ana-Claudia Bernardes Parracho in Atmospheric chemistry and physics, vol 18 n° 22 ([01/11/2018])
[article]
Titre : Global IWV trends and variability in atmospheric reanalyses and GPS observations Type de document : Article/Communication Auteurs : Ana-Claudia Bernardes Parracho , Auteur ; Olivier Bock , Auteur ; Sophie Bastin, Auteur Année de publication : 2018 Projets : REMEMBER / Drobinski, Philippe Article en page(s) : pp 16213 - 16237 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Afrique (géographie physique)
[Termes IGN] analyse diachronique
[Termes IGN] Antarctique
[Termes IGN] circulation atmosphérique
[Termes IGN] données GPS
[Termes IGN] données météorologiques
[Termes IGN] erreur systématique
[Termes IGN] hémisphère Sud
[Termes IGN] humidité de l'air
[Termes IGN] température de surface
[Termes IGN] teneur intégrée en vapeur d'eau
[Termes IGN] variabilitéRésumé : (auteur) This study investigates the means, variability, and trends in integrated water vapour (IWV) from two modern reanalyses (ERA-Interim and MERRA-2) from 1980 to 2016 and ground-based GPS data from 1995 to 2010. It is found that the mean distributions and inter-annual variability in IWV in the reanalyses and GPS are consistent, even in regions of strong gradients. ERA-Interim is shown to exhibit a slight moist bias in the extra-tropics and a slight dry bias in the tropics (both on the order of 0.5 to 1 kg m−2) compared to GPS. ERA-Interim is also generally drier than MERRA-2 over the ocean and within the tropics. Differences in variability and trends are pointed out at a few GPS sites. These differences can be due to representativeness errors (for sites located in coastal regions and regions of complex topography), gaps and inhomogeneities in the GPS series (due to equipment changes), or potential inhomogeneities in the reanalyses (due to changes in the observing system). Trends in IWV and surface temperature in ERA-Interim and MERRA-2 are shown to be consistent, with positive IWV trends generally correlated with surface warming, but MERRA-2 presents a more general global moistening trend compared to ERA-Interim. Inconsistent trends are found between the two reanalyses over Antarctica and most of the Southern Hemisphere, and over central and northern Africa. The uncertainty in current reanalyses remains quite high in these regions, where few in situ observations are available, and the spread between models is generally important. Inter-annual and decadal variations in IWV are also shown to be strongly linked with variations in the atmospheric circulation, especially in arid regions, such as northern Africa and Western Australia, which add uncertainty in the trend estimates, especially over the shorter period. In these regions, the Clausius–Clapeyron scaling ratio is found not to be a good humidity proxy for inter-annual variability and decadal trends. Numéro de notice : A2018-667 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.5194/acp-18-16213-2018 Date de publication en ligne : 15/11/2018 En ligne : http://dx.doi.org/10.5194/acp-18-16213-2018 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94260
in Atmospheric chemistry and physics > vol 18 n° 22 [01/11/2018] . - pp 16213 - 16237[article]A Terrestrial Reference Frame realised on the observation level using a GPS-LEO satellite constellation / Daniel Koenig in Journal of geodesy, vol 92 n° 11 (November 2018)
[article]
Titre : A Terrestrial Reference Frame realised on the observation level using a GPS-LEO satellite constellation Type de document : Article/Communication Auteurs : Daniel Koenig, Auteur Année de publication : 2018 Article en page(s) : pp 1299 - 1312 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] données GPS
[Termes IGN] données GRACE
[Termes IGN] géocentre
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] transformation de HelmertRésumé : (Auteur) Applying a one-step integrated process, i.e. by simultaneously processing all data and determining all satellite orbits involved, a Terrestrial Reference Frame (TRF) consisting of a geometric as well as a dynamic part has been determined at the observation level using the EPOS-OC software of Deutsches GeoForschungsZentrum. The satellite systems involved comprise the Global Positioning System (GPS) as well as the twin GRACE spacecrafts. Applying a novel approach, the inherent datum defect has been overcome empirically. In order not to rely on theoretical assumptions this is done by carrying out the TRF estimation based on simulated observations and using the associated satellite orbits as background truth. The datum defect is identified here as the total of all three translations as well as the rotation about the z-axis of the ground station network leading to a rank-deficient estimation problem. To rectify this singularity, datum constraints comprising no-net translation (NNT) conditions in x, y, and z as well as a no-net rotation (NNR) condition about the z-axis are imposed. Thus minimally constrained, the TRF solution covers a time span of roughly a year with daily resolution. For the geometric part the focus is put on Helmert transformations between the a priori and the estimated sets of ground station positions, and the dynamic part is represented by gravity field coefficients of degree one and two. The results of a reference solution reveal the TRF parameters to be estimated reliably with high precision. Moreover, carrying out a comparable two-step approach using the same data and models leads to parameters and observational residuals of worse quality. A validation w.r.t. external sources shows the dynamic origin to coincide at a level of 5 mm or better in x and y, and mostly better than 15 mm in z. Comparing the derived GPS orbits to IGS final orbits as well as analysing the SLR residuals for the GRACE satellites reveals an orbit quality on the few cm level. Additional TRF test solutions demonstrate that K-Band Range-Rate observations between both GRACE spacecrafts are crucial for accurately estimating the dynamic frame’s orientation, and reveal the importance of the NNT- and NNR-conditions imposed for estimating the components of the dynamic geocenter. Numéro de notice : A2018-464 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-018-1121-7 Date de publication en ligne : 27/02/2018 En ligne : https://doi.org/10.1007/s00190-018-1121-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91063
in Journal of geodesy > vol 92 n° 11 (November 2018) . - pp 1299 - 1312[article]Estimation of satellite position, clock and phase bias corrections / Patrick Henkel in Journal of geodesy, vol 92 n° 10 (October 2018)
[article]
Titre : Estimation of satellite position, clock and phase bias corrections Type de document : Article/Communication Auteurs : Patrick Henkel, Auteur ; Dimitrios Psychas, Auteur ; Christophe Günther, Auteur ; Urs Hugentobler, Auteur Année de publication : 2018 Article en page(s) : pp 1199 - 1217 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] ambiguïté entière
[Termes IGN] données Galileo
[Termes IGN] données GPS
[Termes IGN] double différence
[Termes IGN] erreur de phase
[Termes IGN] horloge atomique
[Termes IGN] positionnement ponctuel précis
[Termes IGN] station de référenceRésumé : (Auteur) Precise point positioning with integer ambiguity resolution requires precise knowledge of satellite position, clock and phase bias corrections. In this paper, a method for the estimation of these parameters with a global network of reference stations is presented. The method processes uncombined and undifferenced measurements of an arbitrary number of frequencies such that the obtained satellite position, clock and bias corrections can be used for any type of differenced and/or combined measurements. We perform a clustering of reference stations. The clustering enables a common satellite visibility within each cluster and an efficient fixing of the double difference ambiguities within each cluster. Additionally, the double difference ambiguities between the reference stations of different clusters are fixed. We use an integer decorrelation for ambiguity fixing in dense global networks. The performance of the proposed method is analysed with both simulated Galileo measurements on E1 and E5a and real GPS measurements of the IGS network. We defined 16 clusters and obtained satellite position, clock and phase bias corrections with a precision of better than 2 cm. Numéro de notice : A2018-461 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-018-1146-y Date de publication en ligne : 02/05/2018 En ligne : https://doi.org/10.1007/s00190-018-1146-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91060
in Journal of geodesy > vol 92 n° 10 (October 2018) . - pp 1199 - 1217[article]Least-squares cross-wavelet analysis and its applications in geophysical time series / Ebrahim Ghaderpour in Journal of geodesy, vol 92 n° 10 (October 2018)PermalinkMethod for real-time self-calibrating GLONASS code inter-frequency bias and improvements on single point positioning / Liang Chen in GPS solutions, vol 22 n° 4 (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)PermalinkDéveloppement d'une procédure d'amélioration du calcul de trajectographie d'un système de cartographie dynamique / Katia Mirande in XYZ, n° 156 (septembre - novembre 2018)PermalinkDetermining inter-system bias of GNSS signals with narrowly spaced frequencies for GNSS positioning / Yumiao Tian in Journal of geodesy, vol 92 n° 8 (August 2018)PermalinkDifferential positioning based on the orthogonal transformation algorithm with GNSS multi-system / Xiao Liang in GPS solutions, vol 22 n° 3 (July 2018)PermalinkOdometer, low-cost inertial sensors, and four-GNSS data to enhance PPP and attitude determination / Zhouzheng Gao in GPS solutions, vol 22 n° 3 (July 2018)PermalinkA sequential network approach for estimating GPS satellite phase biases at the PPP-AR producer-side / Omid Kamali in GPS solutions, vol 22 n° 3 (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)PermalinkFuture global SLR network evolution and its impact on the terrestrial reference frame / Alexander Kehm in Journal of geodesy, vol 92 n° 6 (June 2018)PermalinkGPS receiver phase biases estimable in PPP-RTK networks : dynamic characterization and impact analysis / Baocheng Zhang in Journal of geodesy, vol 92 n° 6 (June 2018)PermalinkInfluences of environmental loading corrections on the nonlinear variations and velocity uncertainties for the reprocessed global positioning system height time series of the crustal movement observation network of China / Peng Yuan in Remote sensing, vol 10 n° 6 (June 2018)PermalinkMulti-GNSS phase delay estimation and PPP ambiguity resolution : GPS, BDS, GLONASS, Galileo / Xingxing Li in Journal of geodesy, vol 92 n° 6 (June 2018)PermalinkOn the impact of GNSS ambiguity resolution: geometry, ionosphere, time and biases / Amir Khodabandeh in Journal of geodesy, vol 92 n° 6 (June 2018)PermalinkPerformance of absolute real-time multi-GNSS kinematic positioning / Kamil Kazmierski in Artificial satellites, vol 53 n° 2 (June 2018)PermalinkComparison of total water vapour content in the Arctic derived from GNSS, AIRS, MODIS and SCIAMACHY / Dunya Alraddawi in Atmospheric measurement techniques, vol 11 n° 5 (May 2018)PermalinkGeodetic VLBI with an artificial radio source on the Moon : a simulation study / Grzegorz Klopotek in Journal of geodesy, vol 92 n° 5 (May 2018)PermalinkCarrier phase bias estimation of geometry-free linear combination of GNSS signals for ionospheric TEC modeling / Anna Krypiak-Gregorczyk in GPS solutions, vol 22 n° 2 (April 2018)PermalinkEstimation of antenna phase center offset for BDS IGSO and MEO satellites / Guanwen Huang in GPS solutions, vol 22 n° 2 (April 2018)PermalinkConstraints on transient viscoelastic rheology of the asthenosphere from seasonal deformation / Kristel Chanard in Geophysical research letters, vol 45 n° 5 (15 March 2018)PermalinkAssessment of multiple GNSS Real-Time SSR products from different analysis centers / Zhiyu Wang in ISPRS International journal of geo-information, vol 7 n° 3 (March 2018)PermalinkKinematic-PPP using single/dual frequency observations from (GPS, GLONASS and GPS/GLONASS) constellations for hydrography / Ashraf Farah in Artificial satellites, vol 53 n° 1 (March 2018)PermalinkValidation of Galileo orbits using SLR with a focus on satellites launched into incorrect orbital planes / Krzysztof Sosnica in Journal of geodesy, vol 92 n° 2 (February 2018)PermalinkPermalinkAn accurate Kriging-based regional ionospheric model using combined GPS/BeiDou observations / Mohamed Abdelazeem in Journal of applied geodesy, vol 12 n° 1 (January 2018)PermalinkL'analyse des performance RTK dans la zone urbaine / Mohamed Hamza Megrerouche in Bulletin des sciences géographiques, n° 31 (2017 - 2018)PermalinkAssessing data from permanent GNSS stations in Algeria / Hassen Abdellaoui in Bulletin des sciences géographiques, n° 31 (2017 - 2018)PermalinkCartographie des déformations de surface sur l’île de Taiwan par interférométrie RADAR Sentinel-1 / Miloud Fekaouni (2018)PermalinkDependency of geodynamic parameters on the GNSS constellation / Stefano Scaramuzza in Journal of geodesy, vol 92 n° 1 (January 2018)PermalinkPermalinkPermalinkPermalinkPermalinkPermalinkPermalinkMise en évidence de l’activité récente des failles du bassin de Naryn (Kyrgyzstan) à partir de données photogrammétriques Pléiades et drone : un nouvel apport pour l’aléa sismique / Aurélie Médard (2018)PermalinkPermalinkPermalinkNavigation des personnes aux moyens des technologies des smartphones et des données d’environnements cartographiés / Fadoua Taia Alaoui (2018)PermalinkParameter estimation with GNSS-reflectometry and GNSS synthetic aperture techniques / Miguel Angel Ribot Sanfelix (2018)PermalinkQuality based approach for updating geographic authoritative datasets from crowdsourced GPS traces / Stefan Ivanovic (2018)PermalinkRattachement ITRF à l'Observatoire Astronomique Félix Aguilar (OAFA) à San Juan, Argentine / Damien Pesce (2018)PermalinkSurveillance des déformations des volcans avec des réseaux de Géocubes : expériences et leçons d’un déploiement sur l’Etna / Mohamed-Amjad Lasri (2018)PermalinkBenefits of satellite clock modeling in BDS and Galileo orbit determination / Yun Qing in Advances in space research, vol 60 n° 12 (15 December 2017)PermalinkPerformance analysis of BDS/GPS precise point positioning with undifferenced ambiguity resolution / Min Wang in Advances in space research, vol 60 n° 12 (15 December 2017)Permalink