Results 21 to 30 of about 12,217,136 (305)
Morphology of quantified ionospheric range spread-F over a wide range of midlatitudes in the Australian longitudinal sector [PDF]
Annales Geophysicae, 2007 Ionograms from a standard vertical-incidence ionosonde chain (nine stations), obtained over a wide range of southern latitudes (in geom.lat. range: 23°–52° S), were digitally scanned at 5-min intervals at nighttime (18:00–06:00 LT)
L. A. Hajkowicz
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Travel distance, frequency of return, and the spread of disease
Scientific Reports, 2023 Human mobility is a key driver of infectious disease spread. Recent literature has uncovered a clear pattern underlying the complexity of human mobility in cities: $$r \cdot f$$ r · f , the product of distance traveled r and frequency of return f per ...
Cate Heine +4 more
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Generation of large-scale equatorial F-region plasma depletions during lowrange spread-F season [PDF]
Annales Geophysicae, 2004 All-sky imaging observations of the F-region OI 630nm nightglow emission allow us to visualize large-scale equatorial plasma depletions, generally known as trans-equatorial plasma bubbles. Strong range type spread-F is the radio signature of these
Y. Sahai +6 more
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Progress in Earth and Planetary Science, 2018 Typical equatorial spread-F events are often said to occur during post-sunset, equinox conditions in most longitude sectors. Recent studies, however, have found an unexpected high occurrence of ionospheric F-region irregularities during June solstice ...
Fabiano S. Rodrigues +6 more
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Equatorial spread-F forecasting model with local factors using the long short-term memory network
Earth, Planets and Space, 2023 The predictability of the nighttime equatorial spread-F (ESF) occurrences is essential to the ionospheric disturbance warning system. In this work, we propose ESF forecasting models using two deep learning techniques: artificial neural network (ANN) and ...
Phimmasone Thammavongsy +4 more
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Automatic Spread-F Detection Using Deep Learning
Radio Science, 2021 Spread-F (SF) is a feature that can be visually observed on ionograms when the ionosonde signals are significantly impacted by plasma irregularities in the ionosphere. Depending on the scale of the plasma irregularities, radio waves of different frequencies are impacted differently when the signals pass through the ionosphere.
Christopher Luwanga +3 more
openaire +2 more sources
Density enhancements associated with equatorial spread F [PDF]
Annales Geophysicae, 2010 Forces governing the three-dimensional structure of equatorial spread-F (ESF) plumes are examined using the NRL SAMI3/ESF three-dimensional simulation code.
J. Krall +3 more
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Journal of Space Weather and Space ClimateUnderstanding the long-term variability of nighttime Spread F (SF) and its drivers is crucial for improving the knowledge of ionospheric disturbances, which impact radio communication, GNSS positioning, and space weather forecasting.
Paul Krishnendu Sekhar +5 more
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Earth, Planets and Space, 2019 Spread-F is known as the electron density inhomogeneous structures in F layer of ionosphere and can usually be classified as frequency spread-F (FSF) and range spread-F (RSF).
Ning Wang +6 more
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Multistation digisonde observations of equatorial spread F in South America [PDF]
Annales Geophysicae, 2004 Directional ionogram and F-region drift observations were conducted at seven digisonde stations in South America during the COPEX campaign from October to December 2002.
B. W. Reinisch +7 more
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