Results 181 to 190 of about 9,731 (202)

Ionospheric oscillations caused by geomagnetic Pi2 pulsations and their observations by multipoint continuous Doppler sounding; first results

Advances in Space Research, 2009
Abstract In 2004, we started operating a continuous Doppler sounding system to investigate ionospheric signatures of infrasonic, short period acoustic gravity waves and geomagnetic pulsations. Since January 2007, four stable 3.59 MHz transmitters have been in operation in the western part of the Czech Republic.
J. Chum, F. Hruška, D. Burešová, T. Šindelářová, P. Hejda, J. Bochníček   +5 more
openaire   +3 more sources

Continuous sound wave Doppler SODAR for short range wind velocity detection

2008 Asia Simulation Conference - 7th International Conference on System Simulation and Scientific Computing, 2008
The authors propose a Doppler SODAR system to detect wind velocity by the frequency shift between the emanation and reception in continuous wave. The proposal is certificated by the simulation of acoustic wave propagation with discrete Huygenpsilas modeling. The experiment verifies the SODAR system which provides reasonable result.
null Lingyun Chai, null Takashi Fukuda, null Ken Yamazaki, null Yukio Kagawa   +3 more
openaire   +1 more source

On continuous-line acoustic array behavior in a laser Doppler sound pressure measurement system.

The Journal of the Acoustical Society of America, 2009
Continuous-line acoustic array behavior in a laser doppler anemometry (LDA) based sound pressure measurement system is considered. Traditional LDA ultrasound measurement systems intentionally minimize the laser beam intersection or interference fringe volume to better achieve point measurements of the sound field.
Michael S. McBeth, Yongxiang Hu
openaire   +1 more source

Analysis of ionospheric disturbances using Continuous Doppler Sounding and airglow

Distinct Ionospheric perturbations such as equatorial plasma bubbles (EPB) and traveling ionospheric disturbances (TID) affect propagation of electromagnetic waves in the ionosphere. Consequently, electromagnetic waves can be used for their investigation. However, the ionospheric perturbations can also be monitored and analysed optically, using airglow
Jaroslav Chum, Šimon Mackovjak, Carlos Martinis, Maria Graciela Molina, Jiri Base   +4 more
openaire   +1 more source

Comparison of gravity waves detected in the lower ionosphere by narrowband VLF measurements and in the F layer by a continuous Doppler sounding system

Gravity waves (GWs) are an important class of atmospheric waves that can propagate from the troposphere up to the upper atmosphere, where they can contribute significantly to the dynamical changes in the ionosphere. The aim of the present contribution is to gain a deeper understanding of the coupling between the lower and the middle ionosphere via ...
Tamás Bozóki, Jaroslav Chum
openaire   +1 more source

Corrigendum to “Complete Operating Deflection Shapes and Model Updating for an Excited Structure in Thermal Environments via an Optimized Continuously Scanning Laser Doppler Vibrometer with a Two-dimension Scan Scheme [Journal of Sound and Vibration 544C (2023) 117411]”

Journal of Sound and Vibration, 2023
Yuhao Hu, Yatao Kang, Kaiping Yu, Weidong Zhu, Rui Zhao   +4 more
openaire   +1 more source

Delay Doppler SAR Focusing and Quantitative Quality Control of the Radar for Europa Assessment and Sounding: Ocean to Near-Surface (REASON) Sounding Data Product

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2021
Kirk M Scanlan, Duncan Young, Gregor Steinbrügge   +2 more
exaly  

Two-Dimensional Imaging of FMCW Ice Sounding Radar Data via the Modified Frequency Scaling Algorithm

IEEE Transactions on Geoscience and Remote Sensing, 2022
Bo Zhao, Liuxiaojun Liu, Guangyou Fang
exaly  

Multi‐Position Facility for HF Doppler Sounding of Ionospheric Inhomogeneities in Ukraine

Radio Science, 2021
Andriy V Zalizovski, E V Mishin, Alexander Koloskov   +2 more
exaly  

Vertical Propagation of Coseismic Ionospheric Disturbances Associated With the Foreshock of the Tohoku Earthquake Observed Using HF Doppler Sounding

Journal of Geophysical Research: Space Physics, 2021
Hiroyuki Nakata, Toshiaki Takano
exaly