Exploració per tema "Astronomy and astrophysics"
Ara es mostren els items 1-20 de 52
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A linear scale height Chapman model supported by GNSS occultation measurements
(2016-05)
Comunicació de congrés
Accés obertGlobal Navigation Satellite Systems (GNSS) radio occultations allow the vertical sounding of the Earth's atmosphere, in particular, the ionosphere. The physical observables estimated with this technique permit to test ... -
Algunes experiències del grup de recerca gAGE sobre transferència tecnològica a l'àmbit de la navegació per satèl·lit.
(2008-12-04)
Audiovisual
Accés obert -
Assessment of centre national d'Études spatiales real-time ionosphere maps in instantaneous precise real-time kinematic positioning over medium and long baselines
(Multidisciplinary Digital Publishing Institute (MDPI), 2020-04-17)
Article
Accés obertPrecise real-time kinematic (RTK) Global Navigation Satellite System (GNSS) positioning requires fixing integer ambiguities after a short initialization time. Originally, it was assumed that it was only possible at a ... -
Assessment of global ionospheric maps performance by means of ionosonde data
(Multidisciplinary Digital Publishing Institute (MDPI), 2020-10-21)
Article
Accés obertThis work presents a new method for assessing global ionospheric maps (GIM) using ionosonde data. The method is based on the critical frequency at the F2 layer directly measured by ionosondes to validate VTEC (vertical ... -
Assessment of St. Patrick's Day 2015 Geomagnetic storm impact on EGNOS
(European Space Agency (ESA), 2015)
Comunicació de congrés
Accés restringit per política de l'editorialThe Monitor project has been designed to monitor ionospheric events that would allow evaluating its impact on European GNSS Systems. It includes a network of ionospheric scintillation monitoring stations in various ... -
Assessment of the capabilities and applicability of ionospheric perturbation indices provided in Europe
(2020-08-01)
Article
Accés obertPerturbations in the ionosphere are of great interest not only for scientific research, but also for applications using transionospheric radiosignals (e.g. GNSS applications and HF communication), because the transmission ... -
Classification of local stellar populations: the improved MEMPHIS algorithm - Part II
(2009-07)
Report de recerca
Accés obertDiscontinuities of the local velocity distribution which are associated with stellar populations are studied from the improved statistical method MEMPHIS (Maximum Entropy of the Mixture Probability from HIerarchical ... -
Coincident observations by the Kharkiv IS radar and ionosonde, DMSP and Arase (ERG) satellites, and FLIP model simulations: implications for the NRLMSISE-00 hydrogen density, plasmasphere, and ionosphere
(2018-08)
Article
Accés obertThis paper reports the results of ionosphere and plasmasphere observations with the Kharkiv incoherent scatter radar and ionosonde, Defense Meteorological Satellite Program, and Arase (ERG) satellites and simulations with ... -
Comments on: confirming geomagnetic Sfe by means of a solar flare detector based on GNSS
(2020-01-01)
Article
Accés obertWe report two comments affecting the paper “Curto JJ, Juan JM & Timoté CC, 2019. Confirming geomagnetic Sfe by means of a solar flare detector based on GNSS. J Space Weather Space Clim 9: A42. https://doi.org/10.1051/sws ... -
Comparative testing of four ionospheric models driven with GPS measurements
(2011-07-28)
Article
Accés obertIn the context of the European Space Agency/European Space Operations Centre funded Study “GNSS Contribution to Next Generation Global Ionospheric Monitoring,” four ionospheric models based on GNSS data (the Electron ... -
Comparing performances of seven different global VTEC ionospheric models in the IGS context
(International GNSS Service (IGS), 2016)
Text en actes de congrés
Accés restringit per política de l'editorialA summary of the main concepts on Global Ionospheric Map(s) (hereinafter GIM(s)) of Vertical Electron Content (VTEC), with special emphasis on their assessment, is presented in this paper. It is based on the experience ... -
Correlation studies for B-spline modeled F2 Chapman parameters obtained from FORMOSAT-3/COSMIC data
(2014)
Article
Accés obertThe determination of ionospheric key quantities such as the maximum electron density of the F2 layer NmF2, the corresponding F2 peak height hmF2 and the F2 scale height HF2 are of high relevance in 4-D ionosphere modeling ... -
D.01. GPS-DF FE characterisation report
(2018-01-14)
Report de recerca
Accés restringit per acord de confidencialitat -
Data gathering and methodology
(2018-10-31)
Report de recerca
Accés obertThe aim of this WP5 is to specify the impact of TID in EGNOS, N-RTK and HF systems through statistical correlation of the performance data recorded from system operators and of TID detection results. The analysis will be ... -
Disc and halo kinematic populations from HIPPARCOS and Geneva-Copenhagen surveys of the solar neighbourhood
(2010-02)
Article
Accés obertDiscontinuities in the local velocity distribution associated with stellar populations are studied using the Maximum Entropy of the Mixture Probability from HIerarchical Segregation (MEMPHIS) improved statistical method, ... -
Dynamical behavior of asteroids near resonance: the 4:1 gap and the 7:2 group
(1999-08)
Article
Accés restringit per política de l'editorialA comparative study of the evolution of the Sun–Jupiter–Asteroid system near the 4:1 and 7:2 resonances is performed by means of two techniques that proceed differently from the Hamiltonian corresponding to the planar ... -
Eccentricity samples: implications on the potential and the velocity distribution
(2017)
Article
Accés obertPlanar and vertical epicycle frequencies and local angular velocity are related to the derivatives up to the second order of the local potential and can be used to test the shape of the potential from stellar disc samples. ... -
Electron density retrieval from truncated Radio Occultation GNSS data
(2019-06-01)
Article
Accés obertThis paper summarizes the definition and validation of two complementary new strategies, to invert incomplete Global Navigation Satellite System Radio-Occultation (RO) ionospheric measurements, such as the ones to be ... -
Evaluation of the ionospheric F2 characteristics inferred from radio occultations exploiting the availability of FORMOSAT-3/COSMIC data over half a solar cycle
(ION Publications (The Institute of navigation), 2016)
Text en actes de congrés
Accés restringit per política de l'editorialThis contribution presents the assessment, on both the maximum electron density (NmF2) and the corresponding peak height of the F2 layer (hmF2), of the overall performance of such ionospheric key parameters inferred from ... -
Experiments on the Ionospheric Models in GNSS
(2013)
Text en actes de congrés
Accés obertIn GNSS, one of the main error sources of the Standard Positioning Service (SPS) is introduced by the ionosphere. Although this error can be cancelled by combining two signals at different frequencies, most of the ...