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Occurrence of GPS Loss of Lock Based on a Swarm Half-Solar Cycle Dataset and Its Relation to the Background Ionosphere

Michael Pezzopane, Alessio Pignalberi, Igino Coco, Giuseppe Consolini, Paola De Michelis, Fabio Giannattasio, Maria Federica Marcucci, Roberta Tozzi
2021 Remote Sensing  
After describing the approach used to classify a GPS loss of lock, the corresponding occurrence is analyzed as a function of latitude, local time, season, and solar activity to identify well-defined patterns  ...  The scope of this study is, on one hand, to characterize the background conditions of the ionosphere for such events and, on the other hand, to pave the way for their possible future modeling.  ...  This is the first time that such an analysis, based on such a large time window, is carried out globally, encompassing half a solar cycle, from the activity peak of 2013 to the minimum of 2020.  ... 
doi:10.3390/rs13112209 fatcat:2usygxtdd5b67d7wjzlxjis25a

Ionospheric Plasma Irregularities based on In‐situ Measurements from the Swarm Satellites

Yaqi Jin, Chao Xiong, Lasse Clausen, Andres Spicher, Daria Kotova, Steffen Brask, Guram Kervalishvili, Claudia Stolle, Wojciech Miloch
2020 Journal of Geophysical Research - Space Physics  
In this study, we present global climatological distributions of ionospheric plasma irregularities based on measurements by the Swarm satellites.  ...  The interplanetary magnetic field Bz modulates the occurrence of ionospheric irregularities at both high and low latitudes.  ...  This research is a part of the 4DSpace Strategic Research Initiative at the University of Oslo.  ... 
doi:10.1029/2020ja028103 fatcat:vy5l2pmgsncx3mflsbwi32yu2e

Plasma patches inside the polar cap and auroral oval: the impact on the spaceborne GPS receiver

Chao Xiong, Fan Yin, Xiaomin Luo, Yaqi Jin, Xin Wan
2019 Journal of Space Weather and Space Climate  
With in situ electron densities exceeding 1.5 × 1012 m−3 at 450–500 km altitude, the patches cause strong signal outages of the global positioning system (GPS) receivers on board Swarm satellites.  ...  This is the first direct evidence to show that when plasma patches are located inside the cusp region, the spaceborne receiver experiences stronger outage of GPS signals.  ...  The solar wind and IMF data are derived from the NASA's ACE mission, and they can be downloaded at the website of http://www.srl.caltech.edu/ACE/ASC/level2/.  ... 
doi:10.1051/swsc/2019028 fatcat:wcfytfy66nf2ddcciwecxoe3re

Bottom-up control of geomagnetic secular variation by the Earth's inner core

Julien Aubert, Christopher C. Finlay, Alexandre Fournier
2013 Nature  
The Earth's plasmasphere: modelling and remote sensing 61 J13 From micro-to macro-scales in the heliosphere and magnetospheres 67 J14 Heliospheric structure during the ascending phase of solar cycle 24  ...  To allow the participants to check this we will wait until after the meeting, to upload a corrected and final version of the Abstract Volume to the web page www.iaga2013.org.mx.  ...  The last extended solar minimum conditions and the beginning of the new 24th solar cycle give us an opportunity to investigate the ionosphere disturbances at background of extremely low electron density  ... 
doi:10.1038/nature12574 pmid:24108054 fatcat:vun7xleqonfzpp4c6waif5ji4e

Understanding space weather to shield society: A global road map for 2015–2025 commissioned by COSPAR and ILWS

Carolus J. Schrijver, Kirsti Kauristie, Alan D. Aylward, Clezio M. Denardini, Sarah E. Gibson, Alexi Glover, Nat Gopalswamy, Manuel Grande, Mike Hapgood, Daniel Heynderickx, Norbert Jakowski, Vladimir V. Kalegaev (+14 others)
2015 Advances in Space Research  
ejections, (3) on understanding the geospace response to variable solar-wind stresses that lead to intense geomagnetically-induced currents and ionospheric and radiation storms, and (4) on developing  ...  We recommend advances through priority focus (1) on observation-based modeling throughout the Sun-Earth system, (2) on forecasts more than 12 hrs ahead of the magnetic structure of incoming coronal mass  ...  phase scintillation may even cause loss of phase lock of the signal.  ... 
doi:10.1016/j.asr.2015.03.023 fatcat:xfsgoua3hjgato3bichbfwl3ha

Conference Digest

2020 2020 IEEE Aerospace Conference  
The Auxiliary Payload Sensor Suite (APSS), a collection of environmental sensors carried by the Interior exploration using Seismic Investigations, Geodesy, and Heat Transport (InSight) lander, is capable  ...  of measuring Martian air temperature, wind speed, atmospheric pressure, and local magnetic fields.  ...  This, in turn, minimizes the time required for carrier lock and thus makes the system more robust to the loss of lock failures.  ... 
doi:10.1109/aero47225.2020.9172613 fatcat:ioqf5ijrx5gvffu3ls34aa2nsq

Program

2020 2020 IEEE International Conference on Consumer Electronics - Taiwan (ICCE-Taiwan)  
We apply multi-output neural network paradigm to predict age and gender simultaneously and the final loss function is based on the combination of age and gender losses.  ...  Finally, a series of experiments have been carried out based on a large-scale real dataset to verify the performance of our proposed detection method.  ...  Virtual full-duplex relaying is a promising technology to recover the multiplexing loss due to the half-duplex relays, by allowing the concurrent transmission of the source and relays.  ... 
doi:10.1109/icce-taiwan49838.2020.9258230 fatcat:g25vw7mzvradxna2grlzp6kgiq

Engineering, Technology & Applied Science Research (ETASR), Vol. 11, No. 2, pp. 6845-7068 [article]

Various
2021 Zenodo  
), and has been awarded a DOAJ seal.  ...  ETASR is indexed in the Web of Science Core Collection (former Web of Science/Thomson Reuters Master Journal List), through the Emerging Sources Citation Index, is a Crossref member (DOI prefix: 10.48084  ...  Afef Hammami, director of the AFA center, and all its members for their cooperation in creating the AD dataset from Arabic voices.  ... 
doi:10.5281/zenodo.4720665 fatcat:mk2prflstjaa3bhkjenwy22s6u

Investigation of Regional Ionospheric Irregularities over Africa (IRIA)

Temitope Seun Oluwadare
2021
The Earth's upper atmosphere – a part of it, the ionosphere- is a dynamic partly ionized region with temporal and spatial variations under different phases of solar activity.  ...  The key parameter of the ionosphere which is closely related to most of these delay effects on radio signals is the electron density and density gradients, in particular - its vertical integral, the Total  ...  GPS signals passing through the ionosphere experience signal strength fluctuation, propagation delay, signal attenuation, signal degradation, and in extreme cases loss of lock.  ... 
doi:10.48440/gfz.b103-21051 fatcat:2bp4stalvzfpplzza44jjkz5aq

Investigation of regional ionospheric irregularities over Africa (IRIA)

Oluwadare Temitope Seun, Technische Universität Berlin, Harald Schuh, Alizadeh M. Mahdi
2021
The Earth's upper atmosphere – a part of it, the ionosphere- is a dynamic partly ionized region with temporal and spatial variations under different phases of solar activity.  ...  The key parameter of the ionosphere which is closely related to most of these delay effects on radio signals is the electron density and density gradients, in particular -its vertical integral, the Total  ...  GPS signals passing through the ionosphere experience signal strength fluctuation, propagation delay, signal attenuation, signal degradation, and in extreme cases loss of lock.  ... 
doi:10.14279/depositonce-11866 fatcat:ulqthcbarvgqraswpuoxvsnxua

Portuguese SKA White Book [article]

Domingos Barbosa, Sonia Antón, João Paulo Barraca, Miguel Bergano, Alexandre C. M. Correia, Dalmiro Maia, Valério A. R. M. Ribeiro
2020 arXiv   pre-print
The meeting was very successful in providing a detailed overview of the SKA status, vision and goals and describes most of the Portuguese contributions to science, technology and the related industry aspirations  ...  This white book stems from the contributions presented at the Portuguese SKA Days, held on the 6th and 7th February 2018 with the presence of the SKA Deputy Director General Alistair McPherson and the  ...  We warmly thank Arnold van Ardenne for invaluable comments and for the inspirational collaboration towards the "greening" of large scale science and the enhancement of its societal impact.  ... 
arXiv:2005.01140v1 fatcat:gijmylrmvfcj3i7dt3wbsr6vhm

Abstract Volume of Sixth Nepal Geolgical Congress on Geology, Natural Resources, Infrastructures, Climate Change and Natural Disasters, 15 – 17 November 2010, Kathmandu, Nepal

Santa Man Rai
2012 Journal of Nepal Geological Society  
<p>This is the full volume of the Abstracts from the <span style="color: #000000;">Sixth Nepal Geolgical Congress on Geology, Natural Resources, Infrastructures, Climate Change and Natural Disasters, 15  ...  – 17 November 2010, Kathmandu, Nepal</span></p><p><br />Journal of Nepal Geological Society, 2010, Vol. 41 (Sp.  ...  The river morphology as studied in satellite image indicates that it is braided on the eastern half and meandered at the western half.  ... 
doi:10.3126/jngs.v41i0.7014 fatcat:cpqkcyfrejcx3llyxiuap374r4

JSE 26:3 Fall 2012 WHOLE ISSUE PDF

Stephen Braude
2012 Journal of Scientific Exploration  
Kishimoto, A. Koyama, K. Nakatsuka, A. Ito, G. Shimizu, and K. Shimizu). Acknowledgments The authors thank the practitioners for their contributions to this study.  ...  Financial support was provided by The Richard Stockton College of New Jersey, the University of California, Irvine, and the Endowment Fund for World Peace and Global Healing.  ...  This is exemplifi ed by the following response: ". . . to return to my normal self and move on in my life without emotional trauma or loss of job . . . " The social well-being category was based on the  ... 
doaj:8eb17ebfb1b2415cbee7fbcc65904781 fatcat:7pqnbow66jgexdbhifk45l6mku

An Astrobiology Strategy for the Exploration of Mars (SSB with the Board on Life Sciences [BLS], 2007) of the Moon (2007) An Assessment of Balance in NASA's Science Programs (2006) Assessment of NASA's Mars Architecture

Daniel Baker, J Bodeau, Genene Fisher, Louis Leffler, Thomas Stansell, Stansell Consulting, Leonard Strachan, Smithsonian Astrophysical, Observatory Staff, Sandra Graham, Theresa Fisher, Program Associate (+11 others)
2005 Workshop Series on Issues in Space Science and Technology: Summary of Space and Earth Science Issues from the Workshop on U.S. Civil Space Policy   unpublished
Cover: (Upper left) A looping eruptive prominence blasted out from a powerful active region on July 29, 2005, and within an hour had broken away from the Sun.  ...  Active regions are areas of strong magnetic forces. Image courtesy of SOHO, a project of international cooperation between the European Space Agency and NASA.  ...  Acknowledgments The author acknowledges useful discussion with D. Gary, NJIT, on this topic, and directs the interested reader to his presentation to IES2008 (Gary, 2008) .  ... 
fatcat:vn4xz2vom5bhfbentyuf37om7y

Advances in Fluxgate Magnetometry for Space Physics

David M Miles
2017
Finally, measurements from e-POP and the adjacent European Space Agency Swarm A and C spacecraft were used to study the dynamics and structuring of discrete arc aurora.  ...  This dataset also shows the limitations of the traditional model for how fluxgate sensor geometry and materials control its thermal gain.  ...  The data are timestamped based on a pulse per second (PPS) input from the GPS receiver, and is transmitted to the spacecraft via a serial data interface.  ... 
doi:10.7939/r30k26p98 fatcat:pv5nl6wytvcyvickw72yvzhxdi
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