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A framework for interactive visual analysis of heterogeneous marine data in an integrated problem solving environment / Shuai Liu in Computers & geosciences, vol 104 (July 2017)
[article]
Titre : A framework for interactive visual analysis of heterogeneous marine data in an integrated problem solving environment Type de document : Article/Communication Auteurs : Shuai Liu, Auteur ; Ge Chen, Auteur ; Shifeng Yao, Auteur ; Fenglin Tian, Auteur ; Wei Liu, Auteur Année de publication : 2017 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] base de données marines
[Termes IGN] carte interactive
[Termes IGN] données spatiotemporelles
[Termes IGN] environnement géographique virtuel
[Termes IGN] monde virtuel
[Termes IGN] océanographie spatiale
[Termes IGN] positionnement par Argos
[Termes IGN] visualisation de données
[Vedettes matières IGN] GéovisualisationRésumé : (auteur) This paper presents a novel integrated marine visualization framework which focuses on processing, analyzing the multi-dimension spatiotemporal marine data in one workflow. Effective marine data visualization is needed in terms of extracting useful patterns, recognizing changes, and understanding physical processes in oceanography researches. However, the multi-source, multi-format, multi-dimension characteristics of marine data pose a challenge for interactive and feasible (timely) marine data analysis and visualization in one workflow. And, global multi-resolution virtual terrain environment is also needed to give oceanographers and the public a real geographic background reference and to help them to identify the geographical variation of ocean phenomena. This paper introduces a data integration and processing method to efficiently visualize and analyze the heterogeneous marine data. Based on the data we processed, several GPU-based visualization methods are explored to interactively demonstrate marine data. GPU-tessellated global terrain rendering using ETOPO1 data is realized and the video memory usage is controlled to ensure high efficiency. A modified ray-casting algorithm for the uneven multi-section Argo volume data is also presented and the transfer function is designed to analyze the 3D structure of ocean phenomena. Based on the framework we designed, an integrated visualization system is realized. The effectiveness and efficiency of the framework is demonstrated. This system is expected to make a significant contribution to the demonstration and understanding of marine physical process in a virtual global environment. Numéro de notice : A2017-128 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.cageo.2017.03.021 En ligne : http://doi.org/10.1016/j.cageo.2017.03.021 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84543
in Computers & geosciences > vol 104 (July 2017)[article]Future Space Service of NavIC (IRNSS) Constellation / Parimal Majithiya in Inside GNSS, vol 12 n° 4 (July - August 2017)
[article]
Titre : Future Space Service of NavIC (IRNSS) Constellation Type de document : Article/Communication Auteurs : Parimal Majithiya, Auteur ; Kriti Khatri, Auteur ; S.C. Bera, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 40 - 45 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] antenne
[Termes IGN] Indian Regional Navigation Satellite System
[Termes IGN] signal GNSSRésumé : (auteur) Today many satellite-based navigation systems are providing terrestrial services. In the near future these systems will also contribute for space service. In this article, we’ll discuss navigation service parameters and Space Service Volume (SSV) for the Indian Regional Navigation Satellite System (IRNSS) constellation now known as NavIC (Navigation with Indian Constellation). The simulations are carried out to derive the received signal power level and availability of the number of satellites for users in Geosynchronous Earth Orbit (GEO), High Earth Orbit (HEO), and Medium Earth Orbit (MEO) satellites. Based on antenna characteristics, the IRNSS SSV is defined and simulated. The group delay parameter considerations are also discussed for this service. Here we’ll take a look at the contribution of the NavIC constellation in future space services. Numéro de notice : A2017-582 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans En ligne : http://www.insidegnss.com/node/5568 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86716
in Inside GNSS > vol 12 n° 4 (July - August 2017) . - pp 40 - 45[article]New optimal smoothing scheme for improving relative and absolute accuracy of tightly coupled GNSS/SINS integration / Xiaohong Zhang in GPS solutions, vol 21 n° 3 (July 2017)
[article]
Titre : New optimal smoothing scheme for improving relative and absolute accuracy of tightly coupled GNSS/SINS integration Type de document : Article/Communication Auteurs : Xiaohong Zhang, Auteur ; Feng Zhu, Auteur ; Xianlu Tao, Auteur ; Rui Duan, Auteur Année de publication : 2017 Article en page(s) : pp 861 – 872 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] algorithme de filtrage
[Termes IGN] combinaison linéaire
[Termes IGN] filtrage du signal
[Termes IGN] positionnement inertiel
[Termes IGN] positionnement par GNSS
[Termes IGN] précision absolue
[Termes IGN] précision relative
[Termes IGN] système à couplage étroit
[Termes IGN] test de performanceRésumé : (auteur) For mobile surveying and mapping applications, tightly coupled integration of global navigation satellite system (GNSS) and Strap down Inertial Navigation System is usually recommended for direct georeferencing since it can provide position, velocity, and attitude information at higher accuracy and better reliability in a self-contained manner. A post-mission smoothing method is applied to optimally use observation information of both systems and to overcome the shortcomings of Kalman filter in GNSS degraded environments. We propose the revised Rauch–Tung–Streibel Smoother (RTSS) and Forward–Backward combination (FBC) smoothing algorithms for tightly coupled integration. From the analysis and field test, it is found that RTSS smoothing mainly improves the relative accuracy, while FBC mainly contributes to the absolute accuracy. With the complementary characteristics of both smoothing algorithms, an optimal new smoothing scheme combining RTSS with FBC is built. The performance of these three smoothing algorithms is evaluated through a real vehicular test. Compared with RTSS and FBC smoothing algorithms, the new smoothing scheme improves the mean 3D position RMS and the mean 3D attitude RMS by 65.7 and 70%, respectively. It provides better accuracy and smoothness for the position, velocity, and attitude at the same time. Numéro de notice : A2017-439 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-017-0601-1 En ligne : https://doi.org/10.1007/s10291-017-0601-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86354
in GPS solutions > vol 21 n° 3 (July 2017) . - pp 861 – 872[article]Review of code and phase biases in multi-GNSS positioning / Martin Håkansson in GPS solutions, vol 21 n° 3 (July 2017)
[article]
Titre : Review of code and phase biases in multi-GNSS positioning Type de document : Article/Communication Auteurs : Martin Håkansson, Auteur ; Anna B. O. Jensen, Auteur ; Milan Horemuz, Auteur ; Gunnar Hedling, Auteur Année de publication : 2017 Article en page(s) : pp 849 - 860 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] code GNSS
[Termes IGN] correction du signal
[Termes IGN] données GNSS
[Termes IGN] modèle ionosphérique
[Termes IGN] phase GNSS
[Termes IGN] positionnement par GNSS
[Termes IGN] précision du positionnement
[Termes IGN] récepteur GNSS
[Termes IGN] résolution d'ambiguïtéRésumé : (auteur) A review of the research conducted until present on the subject of Global Navigation Satellite System (GNSS) hardware-induced phase and code biases is here provided. Biases in GNSS positioning occur because of imperfections and/or physical limitations in the GNSS hardware. The biases are a result of small delays between events that ideally should be simultaneous in the transmission of the signal from a satellite or in the reception of the signal in a GNSS receiver. Consequently, these biases will also be present in the GNSS code and phase measurements and may there affect the accuracy of positions and other quantities derived from the observations. For instance, biases affect the ability to resolve the integer ambiguities in Precise Point Positioning (PPP), and in relative carrier phase positioning when measurements from multiple GNSSs are used. In addition, code biases affect ionospheric modeling when the Total Electron Content is estimated from GNSS measurements. The paper illustrates how satellite phase biases inhibit the resolution of the phase ambiguity to an integer in PPP, while receiver phase biases affect multi-GNSS positioning. It is also discussed how biases in the receiver channels affect relative GLONASS positioning with baselines of mixed receiver types. In addition, the importance of code biases between signals modulated onto different carriers as is required for modeling the ionosphere from GNSS measurements is discussed. The origin of biases is discussed along with their effect on GNSS positioning, and descriptions of how biases can be estimated or in other ways handled in the positioning process are provided. Numéro de notice : A2017-438 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-016-0572-7 En ligne : https://doi.org/10.1007/s10291-016-0572-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86348
in GPS solutions > vol 21 n° 3 (July 2017) . - pp 849 - 860[article]Robust GPS/BDS/INS tightly coupled integration with atmospheric constraints for long-range kinematic positioning / Houzeng Han in GPS solutions, vol 21 n° 3 (July 2017)
[article]
Titre : Robust GPS/BDS/INS tightly coupled integration with atmospheric constraints for long-range kinematic positioning Type de document : Article/Communication Auteurs : Houzeng Han, Auteur ; Jian Wang, Auteur Année de publication : 2017 Article en page(s) : pp 1285 – 1299 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] BDS-INS
[Termes IGN] GPS-INS
[Termes IGN] incertitude de position
[Termes IGN] modèle atmosphérique
[Termes IGN] positionnement cinématique
[Termes IGN] positionnement inertiel
[Termes IGN] résolution d'ambiguïté
[Termes IGN] signal BeiDou
[Termes IGN] signal GNSS
[Termes IGN] système à couplage étroitRésumé : (auteur) The combination of new global navigation satellite system (GNSS) has brought great benefits to reliable positioning and ambiguity resolution (AR), especially in restricted environments. However, kinematic positioning over long ranges is still a challenge due to the presence of significant atmospheric uncertainties, which contaminates the AR process. We present a tightly coupled strategy to integrate GNSS and inertial navigation system (INS) by adding ionospheric and tropospheric delay parameters and extending the stepwise AR by applying the partial ambiguity resolution (PAR) strategy. With the aid of INS predictions, the instantaneous AR can be achieved with the proposed atmospheric prediction model, along with a dual-frequency constraint ambiguity validation test. To remove the faults in both dynamic model and measurement model, a robust innovation filtering algorithm is proposed. A field vehicular test was conducted to validate the positioning performance of the proposed algorithm over long ranges. The results show that a reliable positioning solution is obtainable for the global positioning system (GPS)/BeiDou navigation satellite system (BDS)/INS integration system with baseline larger than 130 km. The average number of fixable ambiguities reaches 14.43 by applying PAR. In addition, the fixing ratio of having fixed more than three ambiguities reaches 98.57%. The results also indicate that the robust innovation filtering can efficiently detect the discrepancies in the filter. Numéro de notice : A2017-446 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-017-0612-y En ligne : https://doi.org/10.1007/s10291-017-0612-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86367
in GPS solutions > vol 21 n° 3 (July 2017) . - pp 1285 – 1299[article]Statistical comparison and combination of GPS, GLONASS, and multi-GNSS multipath reflectometry applied to snow depth retrieval / Sajad Tabibi in IEEE Transactions on geoscience and remote sensing, vol 55 n° 7 (July 2017)PermalinkAn example and analysis for ambiguity resolution in the indoor ZigBee positioning system / Joanna Janicka in Reports on geodesy and geoinformatics, vol 103 n° 1 (June 2017)PermalinkKindred spirits : laser ranging to GNSS satellites / Urs Hugentobler in GPS world, vol 28 n° 5 (May 2017)PermalinkGPS, Galileo, QZSS and IRNSS differential ISBs: estimation and application / Dennis Odijk in GPS solutions, vol 21 n° 2 (April 2017)PermalinkIntegrating 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)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)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)PermalinkEstimation and analysis of Galileo differential code biases / Min Li in Journal of geodesy, vol 91 n° 3 (March 2017)Permalink