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Impact of the atmospheric drag on Starlette, Stella, Ajisai, and Lares Orbits / Krzysztof Sosnica in Artificial satellites, vol 50 n° 1 (March 2015)
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Titre : Impact of the atmospheric drag on Starlette, Stella, Ajisai, and Lares Orbits Type de document : Article/Communication Auteurs : Krzysztof Sosnica, Auteur Année de publication : 2015 Article en page(s) : pp 1 - 18 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] élément orbital
[Termes IGN] freinage atmosphérique
[Termes IGN] orbitographie
[Termes IGN] satellite de télémétrie
[Termes IGN] télémètre laser sur satellite
[Termes IGN] télémétrie laser sur satelliteRésumé : (auteur) The high-quality satellite orbits of geodetic satellites, which are determined using Satellite Laser Ranging (SLR) observations, play a crucial role in providing, e.g., low-degree coefficients of the Earth's gravity field including geocenter coordinates, Earth rotation parameters, as well as the SLR station coordinates. The appropriate modeling of non-gravitational forces is essential for the orbit determination of artificial Earth satellites. The atmospheric drag is a dominating perturbing force for satellites at low altitudes up to about 700-1000 km. This article addresses the impact of the atmospheric drag on mean semi-major axes and orbital eccentricities of geodetic spherical satellites: Starlette, Stella, AJISAI, and LARES. Atmospheric drag causes the semi-major axis decays amounting to about ▲a = -1.2, -.12, -.14, and -.30 m/year for LARES, AJISAI, Starlette, and Stella, respectively. The density of the upper atmosphere strongly depends on the solar and geomagnetic activity. The atmospheric drag affects the along-track orbit component to the largest extent, and the out-of-plane to a small extent, whereas the radial component is almost unaffected by the atmospheric drag Numéro de notice : A2015-287 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/arsa-2015-0001 En ligne : https://doi.org/10.1515/arsa-2015-0001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76406
in Artificial satellites > vol 50 n° 1 (March 2015) . - pp 1 - 18[article]Levelling co-located GNSS and tide gauge stations using GNSS reflectometry / Alvaro Santamaria Gomez in Journal of geodesy, vol 89 n° 3 (March 2015)
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Titre : Levelling co-located GNSS and tide gauge stations using GNSS reflectometry Type de document : Article/Communication Auteurs : Alvaro Santamaria Gomez, Auteur ; Christopher S. Watson, Auteur ; Médéric Gravelle, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 241 - 258 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] analyse comparative
[Termes IGN] erreur systématique
[Termes IGN] étalonnage d'instrument
[Termes IGN] hauteur ellipsoïdale
[Termes IGN] marée océanique
[Termes IGN] marégraphe
[Termes IGN] nivellement
[Termes IGN] point de liaison (géodésie)
[Termes IGN] propagation troposphérique
[Termes IGN] rapport signal sur bruit
[Termes IGN] réflectance de surface
[Termes IGN] réflectométrie par GNSS
[Termes IGN] signal GPSRésumé : (auteur) The GNSS reflectometry technique provides geometric information on the environment surrounding the GNSS antenna including the vertical distance to a reflecting surface. We use sea-surface reflections of GPS signals, recorded as oscillations in signal-to-noise ratio (SNR), to estimate the GNSS to tide gauge (TG) levelling tie, and thus the ellipsoidal heights of the TG. We develop approaches to isolate SNR data dominated by sea-surface reflections and to remove SNR frequency changes caused by the dynamic sea surface. Comparison with in situ levelling at eight sites reveals mean differences at the centimetre level for satellites above 12∘ elevation, with four sites showing differences of 3 cm or smaller. These differences include errors in the in situ levelling, in the antenna calibration model and in the TG measurements, and so represent an upper bound on our technique’s error. Data sampling (1 or 30 s) does not significantly affect the results. We detect systematic errors at the decimetre level related to satellite elevations below 12∘ and to sea-surface height and also differences between results from the L1 and L2 GPS signals larger than 15 cm at two sites. These systematic errors remain unexplained; differences between GPS signals are attributed to receiver-dependent differences in the SNR measurements, while the elevation-dependent error is attributed to unmodelled phase effects such as those caused by tropospheric refraction and sea-surface roughness. Using our approach, we identify a levelling offset of 1.5 cm related to a TG sensor change, illustrating our technique’s value for TG reference monitoring. Numéro de notice : A2015-337 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0784-y Date de publication en ligne : 20/12/2014 En ligne : https://doi.org/10.1007/s00190-014-0784-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76705
in Journal of geodesy > vol 89 n° 3 (March 2015) . - pp 241 - 258[article]Review and principles of PPP-RTK methods / Peter J.G. Teunissen in Journal of geodesy, vol 89 n° 3 (March 2015)
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Titre : Review and principles of PPP-RTK methods Type de document : Article/Communication Auteurs : Peter J.G. Teunissen, Auteur ; Amir Khodabandeh, Auteur Année de publication : 2015 Article en page(s) : pp 217 - 240 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] analyse comparative
[Termes IGN] double différence
[Termes IGN] estimateur
[Termes IGN] méthode de mesure
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement ponctuel précis
[Termes IGN] résolution d'ambiguïtéRésumé : (auteur) PPP-RTK is integer ambiguity resolution-enabled precise point positioning. In this contribution, we present the principles of PPP-RTK, together with a review of different mechanizations that have been proposed in the literature. By application of S-system theory, the estimable parameters of the different methods are identified and compared. Their interpretation is essential for gaining a proper insight into PPP-RTK in general, and into the role of the PPP-RTK corrections in particular. We show that PPP-RTK is a relative technique for which the ‘single-receiver user’ integer ambiguities are in fact double-differenced ambiguities. We determine the transformational links between the different methods and their PPP-RTK corrections, thereby showing how different PPP-RTK methods can be mixed between network and users. We also present and discuss four different estimators of the PPP-RTK corrections. It is shown how they apply to the different PPP-RTK models, as well as why some of the proposed estimation methods cannot be accepted as PPP-RTK proper. We determine analytical expressions for the variance matrices of the ambiguity-fixed and ambiguity-float PPP-RTK corrections. This gives important insight into their precision, as well as allows us to discuss which parts of the PPP-RTK correction variance matrix are essential for the user and which are not. Numéro de notice : A2015-336 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-014-0771-3 Date de publication en ligne : 13/11/2014 En ligne : https://doi.org/10.1007/s00190-014-0771-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76704
in Journal of geodesy > vol 89 n° 3 (March 2015) . - pp 217 - 240[article]Tree species biomass and carbon stock measurement using ground based-LiDAR / Gurveek Singh Maan in Geocarto international, vol 30 n° 3 - 4 (March - April 2015)
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Titre : Tree species biomass and carbon stock measurement using ground based-LiDAR Type de document : Article/Communication Auteurs : Gurveek Singh Maan, Auteur ; Chander kumar Singh, Auteur ; Mritunjay Kumar Singh, Auteur ; Balaji Nagarajan, Auteur Année de publication : 2015 Article en page(s) : pp 293 - 310 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] biomasse
[Termes IGN] données lidar
[Termes IGN] hauteur des arbres
[Termes IGN] semis de points
[Termes IGN] télémétrie laser sur satellite
[Termes IGN] traitement automatique de donnéesRésumé : (Auteur) This study scrutinises the use of terrestrial laser scanning (TLS) to measure diameter at breast height (DBH) and tree height at individual tree species level. LiDAR point cloud scans are collected from uniformly defined control points. The result of processed TLS data demonstrates the precise measurements of tree height and DBH by comparing it with field data (DBH, tree height, tree species and location). The average tree height and DBH obtained through TLS measurements were 9.44 m and 43.30 cm, respectively. A linear equation between TLS derived parameters and field measured values were established, which gave the coefficient of determination (r2) of 0.79 and 0.96 for tree height and DBH, respectively. Further, these parameters were used to calculate above ground biomass (AGB) for individual tree species by considering a non-destructive approach. The total AGB and carbon stock from 80 different trees are computed to be 49.601 and 22.320 tonnes, respectively. Numéro de notice : A2015-248 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2014.925003 Date de publication en ligne : 25/07/2014 En ligne : https://doi.org/10.1080/10106049.2014.925003 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76246
in Geocarto international > vol 30 n° 3 - 4 (March - April 2015) . - pp 293 - 310[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 059-2015021 RAB Revue Centre de documentation En réserve L003 Disponible Measuring thermal expansion using X-band persistent scatterer interferometry / Michele Crosetto in ISPRS Journal of photogrammetry and remote sensing, vol 100 (February 2015)
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Titre : Measuring thermal expansion using X-band persistent scatterer interferometry Type de document : Article/Communication Auteurs : Michele Crosetto, Auteur ; Oriol Montserrat, Auteur ; María Cuevas-González, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 84 - 91 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande Ku
[Termes IGN] bande X
[Termes IGN] bati
[Termes IGN] bâtiment industriel
[Termes IGN] coin réflecteur
[Termes IGN] émission thermique
[Termes IGN] fuite thermique
[Termes IGN] image TerraSAR-X
[Termes IGN] interférométrie
[Termes IGN] interferométrie différentielle
[Termes IGN] tour (bâtiment)
[Termes IGN] viaducRésumé : (auteur) This paper is focused on the estimation of the thermal expansion of buildings and infrastructures using X-band Persistent Scatterer Interferometry (PSI) observations. For this purpose, an extended PSI model is used, which allows separating the thermal expansion from the total observed deformation thus generating a new PSI product: the map of the thermal expansion parameter, named thermal map. The core of the paper is devoted to the exploitation of the information contained in the thermal maps: three examples are discussed in detail, which concern a viaduct, a set of industrial buildings and two skyscrapers. The thermal maps can be used to derive the thermal expansion coefficient of the observed objects and information on their static structure. In addition, the paper illustrates the distortions in the PSI deformation products that occur if the thermal expansion is not explicitly modelled. Finally, an inter-comparison exercise is described, where the thermal expansion coefficients estimated by PSI are compared with those derived by a Ku-band ground-based SAR campaign. Numéro de notice : A2015-055 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2014.05.006 En ligne : https://doi.org/10.1016/j.isprsjprs.2014.05.006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75297
in ISPRS Journal of photogrammetry and remote sensing > vol 100 (February 2015) . - pp 84 - 91[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 081-2015021 RAB Revue Centre de documentation En réserve L003 Disponible Assessing and mitigating the effects of the ionospheric variability on DGPS / Duojie Weng in GPS solutions, vol 19 n° 1 (January 2015)
PermalinkExtending the reach of SBAS : Some aspects of EGNOS performance in Ukraine / Valeriy Konin in Inside GNSS, vol 10 n° 1 (January - February 2015)
PermalinkFrom Data Schemes to Supersonic Codes : GNSS Authentication for Modernized Signals / Oscar Pozzobon in Inside GNSS, vol 10 n° 1 (January - February 2015)
PermalinkGalileo orbit determination using combined GNSS and SLR observations / Stefan Hackel in GPS solutions, vol 19 n° 1 (January 2015)
PermalinkAccounting for Galileo–GPS inter-system biases in precise satellite positioning / Jacek Paziewski in Journal of geodesy, vol 89 n° 1 (January 2015)
PermalinkDetermination of precise satellite orbits and geodetic parameters using satellite laser ranging / Krzysztof Sosnica (2015)
PermalinkFirst Galileo FOC satellite on the air: Will be employable for surveying, precise positionning, and geodesy / Peter Steingenberger in GPS world, vol 26 n° 1 (January 2015)
PermalinkPermalinkGéodésie multi-technique pour la surveillance haute fréquence de glissements de terrains / Pierre Boetzle (2015)
PermalinkGOCE: assessment of GPS-only gravity field determination / Adrian Jäggi in Journal of geodesy, vol 89 n° 1 (January 2015)
PermalinkPermalinkPermalinkPermalinkHierarchical extraction of urban objects from mobile laser scanning data / Bisheng Yang in ISPRS Journal of photogrammetry and remote sensing, vol 99 (January 2015)
PermalinkPermalinkPermalinkPermalinkPermalinkPermalinkLaser ranging data analysis for a colocation campaign of French Transportable Laser Ranging System (FTLRS) in Tahiti / Xiaoni Wang in Journal of geodesy, vol 89 n° 1 (January 2015)
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