Results 101 to 110 of about 413,548 (214)

HF Doppler Radar Observations of Geomagnetic Pulsations

, 2014
Geomagnetic pulsations interact with the ionosphere, which influences the propagation properties of high frequency (HF) radio waves. In this work we present results of an experimental study focused on investigation of relations between the geomagnetic
Fišer, Jiří
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Performance of an OFDM-CDMA HF modem

, 2003
Transmission in the high frequency (HF) band is considered not to be reliable, due to channel's highly dispersive characteristics, frequency selectivity, Doppler spread and multipath propagation.
Pérez-Álvarez, Iván A., Mendieta Otero, Eduardo, Raos, Ivana, Del Cacho, A., Paez Borrallo, José, Santana Sosa, Héctor, Zazo-Bello, Santiago, I. Raos   +7 more
core   +1 more source

Space Surveillance with High-Frequency Radar

Sensors
High-Frequency (HF) radar is well suited to the surveillance of low-earth-orbit space. For large targets, a small deployable HF radar is able to match the detection performance of much larger space surveillance radar systems operating at higher ...
Brendan Hennessy, Heath Yardley, Rob Debnam, Tristan A. Camilleri, Nicholas K. Spencer, David A. Holdsworth, Goeff Warne, Brian Cheung, Sergey Kharabash   +8 more
doaj   +1 more source

SUB-DOPPLER RESOLUTION INFRARED SPECTROSCOPY OF $H_{2}-HF$

, 1987
Author Institution: Department of Chemistry, University of North CarolinaThe optothermal detection method has been used to obtain sub-doppler resolution infrared spectra for the HF stretching vibration of $H_{2}-HF$. At the highest resolution obtained in
Miller, R. E., Jucks, K. W.
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B-Type Natriuretic Peptides (BNP) and Tissue Doppler E/e´ Before and After 4 Weeks Standard Treatment of African Heart Failure Subjects: The ABU-BNP Longitudinal Survey

Vascular Health and Risk Management, 2019
Obiageli Uzoamaka Onyemelukwe,1 Albert Imhoagene Oyati,1 Solomon Sulei Danbauchi,2 Austine Obasohan3 1Department of Medicine, Ahmadu Bello University Teaching Hospital, Zaria, Nigeria; 2Department of Medicine, Jos University Teaching Hospital, Jos ...
Onyemelukwe OU, Oyati AI, Danbauchi SS, Obasohan A   +3 more
doaj  

Use of GPS network data for HF Doppler measurements interpretation

, 2014
9 pages, 7 figures. This article is an advanced version of the report presented at the Beacon Satellite Symposium in Barcelona, Spain on June 7-11 ...
Petrova, Inna R., Bochkarev, Vladimir V., Latypov, Ruslan R.   +2 more
openaire   +2 more sources

Effects of production and loss of electrons on HF Doppler radar measurements of vertical plasma drifts

, 1993
The measurements of vertical plasma drifts at magnetic equator using HF Doppler radar include contributions due to production and loss of electrons and also due to the equatorial electric field.
Nayar, S. R. P., Rao, P. B., Jaya, A. S.
core   +1 more source

Equatorial spread-F characteristics using HF Doppler shift measurements: results from upgraded Doppler sounder system in Tucuman, Argentina

Earth, Planets and Space
Horizontals drifts of equatorial Spread F (ESF) at post-sunset and post-midnight are investigated by analyzing six ESF events observed during the period of November 2022–March 2023.
Habtamu Marew, Jaroslav Chum, Maria Graciela Molina, Uma Ashrani, Carlos Martinis   +4 more
doaj   +1 more source

Subclinical Changes in Type 2 Diabetes Patients with Heart Failure Stage A and B Treated with Oral Semaglutide

Medicina
Background and Objectives: Heart failure (HF) among patients with type 2 diabetes (T2DM) is linked to significant morbidity and mortality, despite the increased availability of new drug therapy.
Larissa Dăniluc, Adina Braha, Oana Elena Sandu, Carina Bogdan, Loredana Suhov, Lina Haj Ali, Alexandra-Iulia Lazăr-Höcher, Alexandra Sima, Adrian Apostol, Mihaela Viviana Ivan   +9 more
doaj   +1 more source

Short-Period Fluctuations in Doppler Frequency of hf Radio Waves -A Preliminary Study [PDF]

, 1973
131-133It is often noticed that at vertical incidence the Doppler frequency of hf radio waves (10 MHz-ATA New Delhi) received via the ionosphere shows quasi-periodic fluctuations with time.
Sastri, J. Hanumath, Subrahmanyam, C.V.
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