Results 61 to 70 of about 1,720 (206)

Physics‐Embedded Deep Learning Reveals the Memory Effect of Ionospheric Electron Density in Response to Solar EUV Forcing

Geophysical Research Letters, Volume 53, Issue 14, 28 July 2026.
Abstract Precise characterization of the electron density profile is crucial for optimizing high frequency communications. Reconstruction models often assume an instantaneous ionospheric response to solar forcing or using time delays, neglecting the time‐integrated cumulative “memory effect” of plasma dynamics.
Hongwei Gong, Hanxian Fang, Die Duan, Chao Xiao, Jintai Li, Chenghao Li, Hongtao Huang, Ganming Ren, Chuyue Zhou, Han Wu   +9 more
wiley   +1 more source

Image processing of digital chest ionograms

The British Journal of Radiology, 1988
Abstract A number of image-processing techniques have been applied to a digital ionographic chest image in order to evaluate their possible effects on this type of image. In order to quantify any effect, a simulated lesion was superimposed on the image at a variety of locations representing different types of structural detail ...
J R, Yarwood, B M, Moores
openaire   +2 more sources

Algorithm for high quality ionograms [PDF]

Electronics Letters, 2000
A new ionogram algorithm, which is highly successful in generating robust and sharp digital ionograms free of artefacts and processing noise, is presented. An important feature of the algorithm is the distortionless zooming capability, which allows the user to concentrate only on the desired magnetoionic components of the ionogram.
Arikan F., Salous, S., Arikan, O.
openaire   +3 more sources

Crowdsourcing ionogram scaling: a citizen science project

, 2021
Poster presented at the 2021 CEDAR Virtual Workshop, June 20-25.Citizen science (CS) is defined as a form of research collaboration or data gathering performed by non-experts or untrained individuals. CS projects benefit scientists by providing resources
Ccanto, Stephany, Vilchez, Amanda, Strobbe, Alessandro, Moyna, Shermely, Rojas, Enrique, Girón, Marie   +5 more
core  

Features of backscatter ionospheric sounding as studied with a chirp ionosonde

Solar-Terrestrial Physics, 2017
We present the results of the studies of backscatter ionospheric sounding (BS) on the basis of a multipurpose chirp ionosonde developed in ISTP SB RAS. We analyze BS experimental data obtained during different seasons from 2005 to 2009.
Ponomarchuk S.N., Kurkin V.I., Penzin M.S.   +2 more
doaj   +1 more source

Optimizing HAARP Beam Pattern for Generation of Strong F‐Region Field‐Aligned Irregularities

Radio Science, Volume 61, Issue 7, July 2026.
Abstract Field‐aligned irregularities (FAIs) are the signatures of plasma turbulence and convection in the mid‐ and high‐latitude F‐region ionosphere, and also provide coherent backscatter targets for HF radars. To serve irregularity generation and characterization studies, we conducted experiments at the High‐frequency Active Auroral Research Program (
T. S. Anderson, E. H. Lay, I. T. Cummings, C. A. Jeffery, P. A. Bernhardt, M. McCarrick, W. A. Bristow, S. J. Briczinski   +7 more
wiley   +1 more source

Ionogram scaling using Hidden Markov Models [PDF]

2018 26th Signal Processing and Communications Applications Conference (SIU), 2018
In this paper, a novel method for electron density reconstruction using ionosonde data is proposed. Proposed technique uses Hidden Markov Models for extracting echoes that provides valuable information about electron density distribution in order to provide input to a model based optimization technique that reconstructs the electron density ...
Gokhan Gok, Yasar Kemal Alp, Orhan Arikan, Feza Arikan   +3 more
openaire   +4 more sources

Table1_Signature of Y-forking in ionogram traces observed at low-mid latitude Indian station, New Delhi, during the earthquake events of 2020: ionosonde observations.docx

, 2023
We have examined ionospheric response to eleven earthquake events measuring less than four on the Richter scale during the year 2020 that occurred in the vicinity of New Delhi (28.6°N, 77.2°E, 42.4°N dip).
M. V. Sunil Krishna (16802025), Arti Bhardwaj (16802016), A. K. Upadhayaya (16802028), Qadeer Ahmed (16802019), Anshul Singh (14337911), Duggirala Pallamraju (15280862), Sumedha Gupta (7005392), S. Sarkhel (16802022), Ankit Gupta (211785), Tarun Pant (3936983)   +9 more
core   +1 more source

New Observations of Cosmic Noise Absorption in the South American Magnetic Anomaly (SAMA) Using a Next‐Generation Riometer

Space Weather, Volume 24, Issue 7, July 2026.
Abstract This study reports the first observations of cosmic noise power (CNP) and cosmic noise absorption (CNA) obtained with a next‐generation riometer installed at the Southern Space Observatory (SSO/INPE) in Brazil, located within the South American Magnetic Anomaly (SAMA).
J. Moro, E. Correia, C. M. Wrasse, J. R. Costa, J. V. Bageston, C. M. Denardini, A. J. Valcorte, L. C. A. Resende, A. M. Santos, L. A. da Silva, J. P. Marchezi, T. S. Trondsen   +11 more
wiley   +1 more source

NOIRE-Net–a convolutional neural network for automatic classification and scaling of high-latitude ionograms

Frontiers in Astronomy and Space Sciences
Millions of ionograms are acquired annually to monitor the ionosphere. The accumulated data contain untapped information from a range of locations, multiple solar cycles, and various geomagnetic conditions.
Andreas Kvammen, Juha Vierinen, Juha Vierinen, Devin Huyghebaert, Theresa Rexer, Andres Spicher, Björn Gustavsson, Jens Floberg   +7 more
doaj   +1 more source