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3D velocity from 3D Doppler radial velocity

J. L. Barron, R. E. Mercer, X. Chen, P. Joe
2005 International journal of imaging systems and technology (Print)  
We present local least squares and regularization frameworks for computing 3D velocity (3D optical flow) from 3D radial velocity measured by a Doppler radar.  ...  We demonstrate the performance of our algorithms quantitatively on synthetic radial velocity data and qualitatively on real radial velocity data, obtained from the Doppler radar at Kurnell Radar station  ...  Radial velocity (measured by the Doppler effect) is the component of 3D velocity along the radial ray from the radar station to some moving 3D atmospheric point.  ... 
doi:10.1002/ima.20048 fatcat:dc6g57hidbcazd3sea3jydaxte

Reconstruction of Typhoon Structure Using 3-Dimensional Doppler Radar Radial Velocity Data with the Multigrid Analysis: A Case Study in an Idealized Simulation Context

Hongli Fu, Xinrong Wu, Wei Li, Yuanfu Xie, Guijun Han, Shaoqing Zhang
2016 Advances in Meteorology  
This study explores the application of 3-dimensional (3D) Doppler radar radial velocities with STMAS for reconstructing a 3D typhoon structure.  ...  A two-scale simulated "typhoon" field is constructed and referred to as "truth," from which randomly distributed conventional wind data and 3D Doppler radar radial wind data are generated.  ...  Lots of techniques have been developed to retrieve wind field from Doppler radar radial velocity observations .  ... 
doi:10.1155/2016/2170746 fatcat:max4wew4dbfhhfkgynxgwdcyqq

A note on Doppler processing of coherent radar backscatter from the water surface: With application to ocean surface wave measurements

Paul A. Hwang, Mark A. Sletten, Jakov V. Toporkov
2010 Journal of Geophysical Research  
The phase information is related to the Doppler frequency shift that can be processed to yield the line-of-sight (radial) velocity of the scattering elements.  ...  The peak component of the Doppler velocity spectrum can be used to obtain the  ...  The peak component of the Doppler velocity spectrum can be used to obtain the spectral peak wave period and the significant wave height can be calculated from the variance of the Doppler velocity [3]  ... 
doi:10.1029/2009jc005870 fatcat:qrc56ye53zewdbzoi6g3ziahgq

Full-volume three-component intraventricular vector flow mapping by triplane color Doppler [article]

Florian Vixège, Alain Berod, Pierre-Yves Courand, Simon Mendez, Franck Nicoud, Philippe Blanc-Benon, Didier Vray, Damien Garcia
2021 arXiv   pre-print
Our results tend to indicate that 3D-iVFM could provide full-volume echocardiographic information on left intraventricular hemodynamics from the clinical modality of triplane color Doppler.  ...  We have generalized the iVFM for a three-dimensional reconstruction (3D-iVFM). 3D-iVFM is able to recover three-component velocity vector fields in a full intraventricular volume by using a clinical echocardiographic  ...  The 3D-iVFM technique reconstructed the radial components with accuracy (𝑟𝑟 = 0.99) since the input information from color Doppler is essentially radial.  ... 
arXiv:2112.03843v2 fatcat:okk23etcajhtrm7k7m2ji3zlzm

Three-Dimensional Speckle-Tracking Echocardiographic Monitoring of Acute Rejection in Heart Transplant Recipients

Guo-Qing Du, Ming-Chon Hsiung, Yan Wu, Shao-Hui Qu, Jeng Wei, Wei-Hsian Yin, Jia-Wei Tian
2016 Journal of ultrasound in medicine  
Two-dimensional, Mmode, pulsed Doppler, and tissue Doppler echocardiography were performed to assess conventional heart structure and function, and 3D full-volume echocardiography was recorded and analyzed  ...  Significant correlations were observed between the left ventricular ejection fraction and global peak longitudinal, global peak radial, and global peak circumferential (r = -0.72; P < .001; r = 0.60; P  ...  In the experience of Stengel et al, 17 the late diastolic transmitral peak velocity derived from tissue Doppler imaging showed good sensitivity of 82% but low specificity of 53% in predicting significant  ... 
doi:10.7863/ultra.15.07013 pmid:27105950 fatcat:hqfmsl4jirevxjxhhqed5xduc4

Maximum Velocity Estimation in Coronary Arteries Using 3-D Tracking Doppler

Stefano Fiorentini, Lars Molgaard Saxhaug, Tore Gruner Bjastad, Espen Holte, Hans Torp, Jorgen Avdal
2018 IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control  
Results from simulations showed that 3D tracking Doppler delivers sonograms with better velocity resolution and spectral SNR compared to conventional PW Doppler.  ...  The imaging sequence was then combined with 3D tracking Doppler for retrospective estimation of maximum velocities.  ...  Simulation from a realistic velocity field PW Doppler, 2D tracking Doppler and 3D tracking Doppler spectra from a realistic velocity field are compared in Figure 9 .  ... 
doi:10.1109/tuffc.2018.2827241 pmid:29993929 fatcat:6fzwngjuvbdojn4aae3y6ctavm

Dust Devil–Like Vortices in an Urban Area Detected by a 3D Scanning Doppler Lidar

Chusei Fujiwara, Kazuya Yamashita, Mikio Nakanishi, Yasushi Fujiyoshi
2011 Journal of Applied Meteorology and Climatology  
Using a three-dimensional scanning coherent Doppler lidar (3D-CDL), we conducted atmospheric boundary layer (ABL) observation in an urban area, Sapporo, Japan, from April of 2005 to June of 2007.  ...  Whenever they appeared, the "fish net" (or "spoke") pattern of wind fields in ABL scale was also detected by the 3D-CDL.  ...  Figure 1 shows a comparison between Doppler velocity and radial convergence obtained from 3D-CDL observation and those from LES as would be observed from the centre of the computational domain.  ... 
doi:10.1175/2010jamc2481.1 fatcat:gupjdmhtjbevdlczxgtlpd47ia

A concept of software extension of 3D low-PRF radar systems to 4D semi-medium-PRF radar systems

Michal Meller, Kamil Stawiarski, Piotr Kaniewski, Jan Matuszewski
2020 Radioelectronic Systems Conference 2019  
The proposed Doppler velocity estimation algorithm is presented in details as well.  ...  We present a concept of software modification of three-dimensional (3D) radar systems, designed to work in the low pulse repetition frequency mode, that equips them with the ability to estimate the radial  ...  The proposed modification equips such systems with the capabilities to estimate the radial velocity and to resolve the range ambiguity occurring for detections of targets that are outside the system's  ... 
doi:10.1117/12.2564904 fatcat:4azkfknxhfh2hppt7fztq4jlhi

Doppler measurement of implosion velocity in fastZ-pinch x-ray sources

B. Jones, C. A. Jennings, J. E. Bailey, G. A. Rochau, Y. Maron, C. A. Coverdale, E. P. Yu, S. B. Hansen, D. J. Ampleford, P. W. Lake, G. Dunham, M. E. Cuneo (+6 others)
2011 Physical Review E  
The observation of Doppler splitting in K-shell x-ray lines emitted from optically thin dopants is used to infer implosion velocities of up to 70 cm/μs in wire-array and gas-puff Z pinches at drive currents  ...  Doppler splitting is obscured in lines with strong opacity, but red-shifted absorption produced by the cooler halo of material backlit by the hot core assembling on axis can be used to diagnose velocity  ...  The line shape from a 3D MHD model is compared (blue).  ... 
doi:10.1103/physreve.84.056408 pmid:22181529 fatcat:vzwsbgveanfvtf7a2bel76e5ua

A Basis for Improving Numerical Forecasting in the Gulf Area by Assimilating Doppler Radar Radial Winds

Fathalla Rihan, Chris Collier
2010 International journal of geosciences  
An approach to assimilate Doppler radar radial winds into a high resolution Numerical Weather Prediction (NWP) model using 3D-Var system is described.  ...  We discuss the types of errors that occur in radar radial winds.  ...  Errors in Doppler Radial Velocity Targets moving away from or towards a radar produce a Doppler shift between the frequency of the transmitted signal (pulse), and the signal reflected from the targets  ... 
doi:10.4236/ijg.2010.12010 fatcat:nfuk5cepvbcx5judup6t7rv3ha

Amplitudes of solar-like oscillations in red giants: Departures from the quasi-adiabatic approximation

R. Samadi, K. Belkacem, M.-A. Dupret, M.J. Goupil, H.-G. Ludwig, C. Barban, F. Baudin, E. Caffau, J. Montalbán, A. Noels, V. Van Grootel
2013 EPJ Web of Conferences  
Departure from adiabatic eigenfunction is a very likely explanation that is investigated in the present work using a 3D hydrodynamical model of the surface layers of a representative red giant star. a  ...  CoRoT and Kepler measurements reveal us that the amplitudes of solar-like oscillations detected in red giant stars scale from stars to stars in a characteristic way.  ...  (7) is compared with the stars whose V max has been measured so far in Doppler velocity from the ground.  ... 
doi:10.1051/epjconf/20134303008 fatcat:ecqurbjz5fcpvguahulxpp2txm

3D photospheric velocity field of a supergranular cell

D. Del Moro, S. Giordano, F. Berrilli
2007 Astronomy and Astrophysics  
The full 3D velocity vector field for the SG has been reconstructed at two different photospheric heights.  ...  The SG cell we investigated seems to be organized with an almost radial flow from its centre to the border.  ...  Combining the horizontal velocity fields retrieved from the Dopplergrams by the TST and the Doppler LoS velocity, the 3D vector field has been reconstructed for the FeII 722.4 nm and FeI 709.0 nm lines  ... 
doi:10.1051/0004-6361:20077595 fatcat:sdqalnotnzchznpke3goosj3pe

Effect of Doppler Radial Velocity Data Assimilation on the Simulation of a Typhoon Approaching Taiwan: A Case Study of Typhoon Aere (2004)

Hsin-Hung Lin, Pay-Liam Lin, Qingnong Xiao, Ying-Hwa Kuo
2011 Terrestrial, Atmospheric and Oceanic Sciences  
Overall, the assimilation of Doppler radial velocity data reduced the intensity error (in wind speed) by about 25%.  ...  The results show that once the Doppler radial velocities were assimilated into the model, the typhoon's circulation intensified within one hour.  ...  Comments from Tai-Chi Chen Wang, Chung-Hsiung Sui, Fang-Yi Cheng, Yu-Chieng Liou and the reviewers are greatly appreciated.  ... 
doi:10.3319/tao.2010.10.08.01(a) fatcat:oqd53pey7vgajcivg5xywkrkka

Three-Dimensional Velocity Distribution Measurement Using Ultrasonic Velocity Profiler with Developed Transducer

Naruki Shoji, Hiroshige Kikura, Hideharu Takahashi, Wongsakorn Wongsaroj
2022 Journal of Flow Control Measurement and Visualization  
As the fluid moves through this setup, four Doppler frequencies are obtained. The multi-dimensional velocity information along the measurement line can be reconstructed.  ...  This study describes an ultrasonic velocity profiler that uses a new ultrasonic array transducer with unique 5-element configuration, with all five elements acting as transmitters and four elements as  ...  Using the four Doppler frequencies from one measurement volume, the 3D velocity profile, i.e., axial velocity (V x (i)), tangential velocity (V y (i)) with the information of f D1 and f D2 , and radial  ... 
doi:10.4236/jfcmv.2022.101003 fatcat:eargdrqx2vdldaei2zdb5quvya
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