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Descriptif technique du quasi-géoïde gravimétrique QGF16 et de la surface de conversion altimétrique RAF18b / François L'écu (2021)
Titre : Descriptif technique du quasi-géoïde gravimétrique QGF16 et de la surface de conversion altimétrique RAF18b Type de document : Rapport Auteurs : François L'écu, Auteur Mention d'édition : version 1 Editeur : Saint-Mandé : Institut national de l'information géographique et forestière - IGN (2012-) Année de publication : 2021 Collection : Documents techniques du SGM num. 600 82 8671 Importance : 22 p. Format : 21 x 30 cm Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] conversion altimétrique
[Termes IGN] hauteur ellipsoïdale
[Termes IGN] point GNSS nivelé
[Termes IGN] Quasi-Géoïde Français 2016
[Termes IGN] Référence d'Altitudes Françaises 2018Résumé : (auteur) Le document présente les caractéristiques techniques du quasi-géoïde gravimétrique QGF16 et de la surface de conversion altimétrique RAF18b. Note de contenu : 1- Introduction
2- Processus de calcul de quasi-géoïde utilisé au SGM
3- Données utilisées pour le calcul de QGF16
4- Le quasi-géoïde gravimétrique QGF16
5- La surface de conversion altimétrique RAF18bNuméro de notice : 28382 Affiliation des auteurs : IGN (2020- ) Thématique : POSITIONNEMENT Nature : Rapport d'étude technique nature-HAL : Rapport DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98603 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 28382-01 7D Livre SGM K001 Exclu du prêt Determination of precise Galileo orbits using combined GNSS and SLR observations / Grzegorz Bury in GPS solutions, vol 25 n° 1 (January 2021)
[article]
Titre : Determination of precise Galileo orbits using combined GNSS and SLR observations Type de document : Article/Communication Auteurs : Grzegorz Bury, Auteur ; Krzysztof Sosnica, Auteur ; Radoslaw Zajdel, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 11 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Techniques orbitales
[Termes IGN] données GNSS
[Termes IGN] données TLS (télémétrie)
[Termes IGN] Galileo
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] orbite précise
[Termes IGN] orbitographie
[Termes IGN] pondérationRésumé : (auteur) Galileo satellites are equipped with laser retroreflector arrays for satellite laser ranging (SLR). In this study, we develop a methodology for the GNSS-SLR combination at the normal equation level with three different weighting strategies and evaluate the impact of laser observations on the determined Galileo orbits. We provide the optimum weighting scheme for precise orbit determination employing the co-location onboard Galileo. The combined GNSS-SLR solution diminishes the semimajor axis formal error by up to 62%, as well as reduces the dependency between values of formal errors and the elevation of the Sun above the orbital plane—the β angle. In the combined solution, the standard deviation of the SLR residuals decreases from 36.1 to 29.6 mm for Galileo-IOV satellites and |β|> 60°, when compared to GNSS-only solutions. Moreover, the bias of the Length-of-Day parameter is 20% lower for the combined solution when compared to the microwave one. As a result, the combination of GNSS and SLR observations provides promising results for future co-locations onboard the Galileo satellites for the orbit determination, realization of the terrestrial reference frames, and deriving geodetic parameters. Numéro de notice : A2021-008 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-020-01045-3 Date de publication en ligne : 31/10/2020 En ligne : https://doi.org/10.1007/s10291-020-01045-3 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96298
in GPS solutions > vol 25 n° 1 (January 2021) . - n° 11[article]
Titre : Review of Reference Frame Representations for a Deformable Earth Type de document : Article/Communication Auteurs : Zuheir Altamimi , Auteur ; Paul Rebischung , Auteur ; Xavier Collilieux , Auteur ; Laurent Métivier , Auteur ; Kristel Chanard , Auteur Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2021 Collection : International Association of Geodesy Symposia, ISSN 0939-9585 num. 151 Conférence : IAG 2018, 9th Hotine-Marussi Symposium on Mathematical Geodesy 18/06/2018 22/06/2018 Rome Italie Proceedings Springer Importance : pp 51 - 56 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] erreur systématique
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] repère de référence
[Termes IGN] station de référence
[Termes IGN] système de référence géodésiqueRésumé : (auteur) Our planet Earth is constantly deforming under the effects of geophysical processes that cause linear and nonlinear displacements of the geodetic stations upon which the International Terrestrial Reference Frame (ITRF) is established. The ITRF has traditionally been defined as a secular (linear) frame in which station coordinates are described by piecewise linear functions of time. Nowadays, some particularly demanding applications however require more elaborate reference frame representations that can accommodate non-linear displacements of the reference stations. Two such types of reference frame representations are reviewed: the usual linear frame enhanced with additional parametric functions such as seasonal sine waves, and non-parametric time series of quasi-instantaneous reference frames. After introducing those two reference frame representations, we briefly review the systematic errors present in geodetic station position time series. We finally discuss the practical issues raised by the existence of these systematic errors for the implementation of both types of non-linear reference frames. Numéro de notice : C2018-076 Affiliation des auteurs : LASTIG LAREG (2012-mi2018) Thématique : POSITIONNEMENT Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1007/1345_2019_66 Date de publication en ligne : 17/05/2019 En ligne : http://dx.doi.org/10.1007/1345_2019_66 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91473
Titre : Stochastic models for geodesy and geoinformation science Type de document : Monographie Auteurs : Frank Neitzel, Éditeur scientifique Editeur : Bâle [Suisse] : Multidisciplinary Digital Publishing Institute MDPI Année de publication : 2021 Importance : 200 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-3-03943-982-9 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] B-Spline
[Termes IGN] covariance
[Termes IGN] erreur de phase
[Termes IGN] incertitude de mesurage
[Termes IGN] interférométrie à très grande base
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] méthode des moindres carrés
[Termes IGN] modèle stochastique
[Termes IGN] phase GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] réseau géodésique
[Termes IGN] télémétrie laser aéroportéRésumé : (éditeur) In geodesy and geoinformation science, as well as in many other technical disciplines, it is often not possible to directly determine the desired target quantities. Therefore, the unknown parameters must be linked with the measured values by a mathematical model which consists of the functional and the stochastic models. The functional model describes the geometrical–physical relationship between the measurements and the unknown parameters. This relationship is sufficiently well known for most applications. With regard to the stochastic model, two problem domains of fundamental importance arise: 1. How can stochastic models be set up as realistically as possible for the various geodetic observation methods and sensor systems? 2. How can the stochastic information be adequately considered in appropriate least squares adjustment models? Further questions include the interpretation of the stochastic properties of the computed target values with regard to precision and reliability and the use of the results for the detection of outliers in the input data (measurements). In this Special Issue, current research results on these general questions are presented in ten peer-reviewed articles. The basic findings can be applied to all technical scientific fields where measurements are used for the determination of parameters to describe geometric or physical phenomena. Note de contenu : 1- Total least-squares collocation: An optimal estimation technique for the EIV-model with prior information
2- Weighted Total Least Squares (WTLS) Solutions for straight line fitting to 3D point data
3- Stochastic properties of confidence ellipsoids after least squares adjustment, derived from GUM analysis and Monte Carlo simulations
4- Mean shift versus variance inflation approach for outlier detection—A comparative study
5- A generic approach to covariance function estimation using ARMA-models
6- Evaluation of VLBI observations with sensitivity and robustness analyses
7- Variance reduction of sequential Monte Carlo approach for GNSS phase bias estimation
8- Automatic calibration of process noise matrix and measurement noise covariance for multi-GNSS precise point positioning
9- Elementary error model applied to terrestrial laser scanning measurements: Study case arch Dam Kops
10- On estimating the hurst parameter from least-squares residuals. Case study: Correlated terrestrial laser scanner range noiseNuméro de notice : 28459 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE/POSITIONNEMENT Nature : Recueil / ouvrage collectif DOI : 10.3390/books978-3-03943-982-9 En ligne : http://dx.doi.org/10.3390/books978-3-03943-982-9 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99044 CORS usage for GPS survey in the greater accra region: Advantages, limitation, and suggested remedies / Sebastian Botsyo in Journal of Geovisualization and Spatial Analysis, vol 4 n° 2 (December 2020)
[article]
Titre : CORS usage for GPS survey in the greater accra region: Advantages, limitation, and suggested remedies Type de document : Article/Communication Auteurs : Sebastian Botsyo, Auteur ; Bernard Borketey Bortei, Auteur ; John Ayer, Auteur Année de publication : 2020 Article en page(s) : n° 20 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] balise
[Termes IGN] Continuously Operating Reference Station network
[Termes IGN] géopositionnement
[Termes IGN] Ghana
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] positionnement statique
[Termes IGN] station de référence
[Termes IGN] station permanente
[Termes IGN] système de référence localRésumé : (auteur) The use of Continuously Operating Reference Stations (CORS) enables surveyors to differentially correct static Global Positioning System (GPS) measurements. CORS are designed to support the broad spectrum of post-processed, relative GPS techniques, and applications. Enhancing geospatial positioning applications of CORS data involves the critical role in defining the nation’s geodetic reference system. With the establishment of a coordinated system of CORS, an Online Positioning User Service can become available for processing in single positioning mode to provide corresponding accurate and homogeneous positional coordinates. The Survey and Mapping Division (SMD), Lands Commission of Ghana, has established four CORS in the Greater Accra, and Ashanti, Western and Brong-Ahafo Regions, respectively, to provide a basic CORS network in accordance with the International Terrestrial Reference Frame (ITRF). However, most surveyors continue to reference their works in these regions to ground survey beacons that have been coordinated and adjusted by variable survey methods. This obviously makes homogeneity of data unpredictable. This study explored the extent of usage of existing CORS network established by SMD with particular focus on the CORS in the Greater Accra Region for GPS surveys and to determine its usefulness in ensuring homogeneity in GPS data collection. The professional participatory (interviews) technique was coupled with differential GPS field observations with the CORS as reference in one case and ground control stations as reference in the other in making relatively conclusive analysis. Test results showed that GPS field survey of an approximate range of 23 km away from the Accra CORS yielded an average positional change in Northings and Eastings of − 0.790 m, − 0.176 m and − 0.681 m, − 0.098 m for single and dual frequency, respectively, in different localities within the study area. Beyond a range of 25 km from the Accra CORS, the average positional change in Northings and Eastings are − 0.536 m, − 0.007 m and − 1.370 m, 0.334 m for single and dual frequency respectively. Of 128 geomatic professionals interviewed, 39% are aware of the availability of COR stations in Greater Accra, 61% are unaware, and 28% are aware and users of the Accra CORS whereas 11% are aware but non-users of the Accra COR station. Of all users sampled, 17.5% are regular and frequent users of the Accra COR station and 10.5% are occasional or seldom users. The results show that the Accra CORS is vital to ensuring a uniform homogenous GPS data. However, very few people are using it due to low public awareness of the usefulness of the CORS among professional surveyors and other users and a cumbersome, bureaucratic nature in CORS data acquisition for post-processing and RTK GPS surveys. Numéro de notice : A2020-723 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s41651-020-00061-8 Date de publication en ligne : 11/09/2020 En ligne : https://doi.org/10.1007/s41651-020-00061-8 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96324
in Journal of Geovisualization and Spatial Analysis > vol 4 n° 2 (December 2020) . - n° 20[article]Reference system origin and scale realization within the future GNSS constellation “Kepler” / Susanne Glaser in Journal of geodesy, vol 94 n° 12 (December 2020)PermalinkGenèse d'une norme internationale géodésique : l'ITRS et ses réalisations / Thierry Gattacceca in XYZ, n° 164 (septembre 2020)PermalinkGNSS scale determination using calibrated receiver and Galileo satellite antenna patterns / Arturo Villiger in Journal of geodesy, vol 94 n° 9 (September 2020)PermalinkMonitoring the deformation of a concrete dam: a case study on the Deriner Dam, Artvin, Turkey / Berkant Konakoglu in Geomatics, Natural Hazards and Risk, vol 11 n° 1 (2020)PermalinkLes pérégrinations d'un topographe en Chine / Bernard Flacelière in XYZ, n° 164 (septembre 2020)PermalinkConstrained and network multi-receiver single-epoch RTK positioning / Mieczysław Bakula in Survey review, vol 52 n° 373 (July 2020)PermalinkTriangulation network of 1929–1944 of the first 1:500 urban map of València / Miriam Villar-Cano in Survey review, vol 52 n° 373 (July 2020)PermalinkPast and present ITRF solutions from geophysical perspectives / Laurent Métivier in Advances in space research, vol 65 n° 12 (15 June 2020)PermalinkGéodésie de poche : toute la géodésie dans votre main / Gilles Canaud in XYZ, n° 163 (juin 2020)PermalinkAccounting for spatiotemporal correlations of GNSS coordinate time series to estimate station velocities / Clément Benoist in Journal of geodynamics, vol 135 (April 2020)Permalink