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Design principles of a stream-based framework for mobility analysis / Loic Salmon in Geoinformatica, vol 21 n° 2 (April - June 2017)
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Titre : Design principles of a stream-based framework for mobility analysis Type de document : Article/Communication Auteurs : Loic Salmon, Auteur ; Cyril Ray, Auteur Année de publication : 2017 Article en page(s) : pp 237 - 261 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse spatiale
[Termes IGN] approche holistique
[Termes IGN] cartographie à la volée
[Termes IGN] flux de données
[Termes IGN] gestion de trafic
[Termes IGN] navigation maritime
[Termes IGN] objet mobile
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] système de gestion de flux de données
[Termes IGN] temps réel
[Termes IGN] traitement interactif
[Vedettes matières IGN] GéovisualisationRésumé : (Auteur) Trajectory analysis is of crucial importance in several fields as social analysis, zoology, climatology or traffic monitoring. Over the last decade, the number of mobile systems and devices recording their positions has grown significantly generating a deluge of spatial and temporal data to analyze. This increasing volume of data raises numerous issues in terms of storage, processing and extraction of information. Previous works considering movement analysis have been mainly oriented towards either archived data processing and mining or continuous handling of incoming streams. The research developed in this paper introduces the design principles of a holistic approach combining real-time processing and archived data analysis to process mobility data “on the fly”. This solution aims to provide better results comparing to both purely offline and online approaches. This research considers distributed data and processing to be more efficient. The design principles are applied to maritime traffic analysis and a few representative examples are introduced to demonstrate the relevance of our approach. Numéro de notice : A2017-070 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-016-0256-z En ligne : http://dx.doi.org/10.1007/s10707-016-0256-z Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84297
in Geoinformatica > vol 21 n° 2 (April - June 2017) . - pp 237 - 261[article]Galileo status: orbits, clocks, and positioning / Peter Steigenberger in GPS solutions, vol 21 n° 2 (April 2017)
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Titre : Galileo status: orbits, clocks, and positioning Type de document : Article/Communication Auteurs : Peter Steigenberger, Auteur ; Oliver Montenbruck, Auteur Année de publication : 2017 Article en page(s) : pp 319 – 331 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] constellation Galileo
[Termes IGN] données Galileo
[Termes IGN] Galileo
[Termes IGN] positionnement ponctuel précisRésumé : (auteur) The European Global Navigation Satellite System Galileo is close to declaration of initial services. The current constellation comprises a total of 12 active satellites, four of them belonging to the first generation of In-Orbit Validation satellites, while the other eight are Full Operational Capability (FOC) satellites. Although the first pair of FOC satellites suffered from a launch anomaly resulting in an elliptical orbit, these satellites can be used for scientific applications without relevant limitations. The quality of broadcast orbits and clocks has significantly improved since the beginning of routine transmissions and has reached a signal-in-space range error of 30 cm. Precise orbit products generated by the scientific community achieve an accuracy of about 5 cm if appropriate models for the solar radiation pressure are applied. The latter is also important for an assessment of the clock stability as orbit errors are mapped to the apparent clock. Dual-frequency single point positioning with broadcast orbits and clocks of nine Galileo satellites that have so far been declared healthy already enables an accuracy at a few meters. Galileo-only precise point positioning approaches a precision of 2 cm in static mode using daily solutions. Numéro de notice : A2017-211 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-016-0566-5 En ligne : http://dx.doi.org/10.1007/s10291-016-0566-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85051
in GPS solutions > vol 21 n° 2 (April 2017) . - pp 319 – 331[article]GPS, Galileo, QZSS and IRNSS differential ISBs: estimation and application / Dennis Odijk in GPS solutions, vol 21 n° 2 (April 2017)
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Titre : GPS, Galileo, QZSS and IRNSS differential ISBs: estimation and application Type de document : Article/Communication Auteurs : Dennis Odijk, Auteur ; Nandakumaran Nadarajah, Auteur ; Safoora Zaminpardaz, Auteur ; Peter J.G. Teunissen, Auteur Année de publication : 2017 Article en page(s) : pp 439 – 450 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] base géodésique
[Termes IGN] constellation GNSS
[Termes IGN] données GNSS
[Termes IGN] erreur systématique inter-systèmes
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement différentiel
[Termes IGN] positionnement par GNSS
[Termes IGN] résolution d'ambiguïtéRésumé : (auteur) Knowledge of inter-system biases (ISBs) is essential to combine observations of multiple global and regional navigation satellite systems (GNSS/RNSS) in an optimal way. Earlier studies based on GPS, Galileo, BDS and QZSS have demonstrated that the performance of multi-GNSS real-time kinematic positioning is improved when the differential ISBs (DISBs) corresponding to signals of different constellations but transmitted at identical frequencies can be calibrated, such that only one common pivot satellite is sufficient for inter-system ambiguity resolution at that particular frequency. Recently, many new GNSS satellites have been launched. At the beginning of 2016, there were 12 Galileo IOV/FOC satellites and 12 GPS Block IIF satellites in orbit, while the Indian Regional Navigation Satellite System (IRNSS) had five satellites launched of which four are operational. More launches are scheduled for the coming years. As a continuation of the earlier studies, we analyze the magnitude and stability of the DISBs corresponding to these new satellites. For IRNSS this article presents for the first time DISBs with respect to the L5/E5a signals of GPS, Galileo and QZSS for a mixed-receiver baseline. It is furthermore demonstrated that single-frequency (L5/E5a) ambiguity resolution is tremendously improved when the multi-GNSS observations are all differenced with respect to a common pivot satellite, compared to classical differencing for which a pivot satellite is selected for each constellation. Numéro de notice : A2017-214 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-016-0536-y En ligne : http://dx.doi.org/10.1007/s10291-016-0536-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85084
in GPS solutions > vol 21 n° 2 (April 2017) . - pp 439 – 450[article]GPS real-time precise point positioning for aerial triangulation / Junbo Shi in GPS solutions, vol 21 n° 2 (April 2017)
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Titre : GPS real-time precise point positioning for aerial triangulation Type de document : Article/Communication Auteurs : Junbo Shi, Auteur ; Xiuxiao Yuan, Auteur ; Yang Cai, Auteur ; Gaojing Wang, Auteur Année de publication : 2017 Article en page(s) : pp 405 – 414 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] aérotriangulation
[Termes IGN] antenne
[Termes IGN] coordonnées GNSS
[Termes IGN] point de vérification
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] positionnement ponctuel précisRésumé : (auteur) We extend the application of real-time kinematic PPP to aerial triangulation using GPS to determine coordinates of the antenna installed on the airplane, using real-time satellite products from IGS and the CNES Analysis Center. In order to verify the performance of real-time kinematic PPP for aerial triangulation, three tests with varying aerial and ground conditions are assessed. Numerical results show that real-time kinematic PPP using IGS real-time products of 5-cm orbit accuracy and 0.1- to 0.3-ns clock precision can provide comparable accuracy for aerial photogrammetric mapping at the scale of 1:1000 as does post-mission kinematic PPP using IGS final products. Millimeter-to-centimeter-level differences and centimeter-to-2-decimeter differences are identified for horizontal and vertical coordinates of ground check points, respectively, in the three tests. The comparison between real-time IGS and CNES products for GPS positioning and aerial triangulation unveils that real-time products with a better clock precision can result in better performance of GPS real-time kinematic PPP as applied to aerial triangulation. Numéro de notice : A2017-248 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-016-0532-2 En ligne : http://dx.doi.org/10.1007/s10291-016-0532-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85055
in GPS solutions > vol 21 n° 2 (April 2017) . - pp 405 – 414[article]Integrating uncertainty propagation in GNSS radio occultation retrieval: From bending angle to dry-air atmospheric profiles / Jakob Schwarz in Earth and space science, vol 4 n° 4 (April 2017)
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Titre : Integrating uncertainty propagation in GNSS radio occultation retrieval: From bending angle to dry-air atmospheric profiles Type de document : Article/Communication Auteurs : Jakob Schwarz, Auteur ; Gottfried Kirchengast, Auteur ; Marc Schwaerz, Auteur Année de publication : 2017 Article en page(s) : pp 200 - 228 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] covariance
[Termes IGN] données GNSS
[Termes IGN] incertitude géométrique
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] occultation du signal
[Termes IGN] positionnement par GNSS
[Termes IGN] température en altitude
[Termes IGN] vapeur d'eau
[Vedettes matières IGN] Traitement de données GNSSRésumé : (auteur) Global Navigation Satellite Systems (GNSS) Radio Occultation (RO) observations, globally available as a continuous record since 2001, are highly accurate and long-term stable data records. Essential climate variables for the thermodynamic state of the free atmosphere, such as temperature and tropospheric water vapor profiles (involving background information), can be derived from these records, which consequentially have the potential to serve as climate benchmark data. In order to exploit this potential, atmospheric profile retrievals need to be very accurate and the remaining uncertainties need to be quantified and traced throughout the retrieval chain. The new Reference Occultation Processing System at the Wegener Center aims to deliver such an accurate retrieval chain with integrated uncertainty propagation. Here we introduce and demonstrate the algorithms implemented for uncertainty propagation from RO bending angle profiles to dry-air variables (pressure and temperature), for estimated random and systematic uncertainties, and for coestimates of observation-to-background weighting ratio profiles. We estimated systematic uncertainty profiles with the same operators as used for the basic profiles retrieval. The random uncertainty propagation was integrated by a covariance propagation approach and validated using Monte-Carlo ensemble methods. We present the results of the validation and demonstrate how the algorithm performs for individual simulated RO events and for ensembles of real RO events. We also compare the new results from the integrated uncertainty propagation to previous ones from empirical error analyses for RO-retrieved atmospheric profiles. We find that the new uncertainty estimation chain shows robust performance and is in good agreement with previous comparable results. Numéro de notice : A2017-269 Affiliation des auteurs : non IGN Thématique : INFORMATIQUE/MATHEMATIQUE/POSITIONNEMENT Nature : Article DOI : 10.1002/2016EA000234 En ligne : https://doi.org/10.1002/2016EA000234 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85294
in Earth and space science > vol 4 n° 4 (April 2017) . - pp 200 - 228[article]Precision on board : orbit determination of LEO satellites with real-time corrections / André Hauschild in GPS world, vol 28 n° 4 (April 2017)
PermalinkRapid initialization of real-time PPP by resolving undifferenced GPS and GLONASS ambiguities simultaneously / Jianghui Geng in Journal of geodesy, vol 91 n° 4 (April 2017)
PermalinkRapid PPP ambiguity resolution using GPS+GLONASS observations / Yanyan Liu in Journal of geodesy, vol 91 n° 4 (April 2017)
PermalinkA virtual globe-based visualization and interactive framework for a small craft navigation assistance system in the near sea / Xinzhu Liu in Journal of Traffic and Transportation Engineering (English Edition), n° (April 2017)
PermalinkEvaluation of quad-constellation GNSS precise point positioning in Egypt / Emad El Manaily in Artificial satellites, vol 52 n° 1 (March 2017)
PermalinkAdaptive time-variant adjustment for the positioning errors of a mobile mapping platform in GNSS-hostile areas / Jiawei Han in Survey review, vol 49 n° 352 (March 2017)
PermalinkAirborne Lidar/INS/GNSS : algorithm uses fuzzy controlled Scale Invariant Feature Transform (SIFT) / Haowei Xu in GPS world, vol 28 n° 3 (March 2017)
PermalinkPermalinkBias compensation for rational function model based on total least squares / Anzhu Yu in Photogrammetric record, vol 32 n° 157 (March - May 2017)
PermalinkCalcul du quasi-géoïde QGF16 et de la grille de conversion altimétrique RAF16 : état d'avancement et perspectives / François L'écu in XYZ, n° 150 (mars - mai 2017)
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