Results 51 to 60 of about 118,769 (293)
What is Doppler ultrasound? [PDF]
, 2011 The term Doppler should be capitalized because it refers to Christian Johann Doppler, an Austrian physicist (1803–1853). He described a phenomenon whereby the frequency of sound changes when it is reflected off a moving object.
Vassallo, Pierre
core
The Ray Theory of Doppler Frequency Shifts [PDF]
Australian Journal of Physics, 1968 A general expression is obtained according to ray theory for the Doppler frequency shift observed when both receiver and transmitter are in motion in a time-varying anisotropic but lossless medium. The result is obtained using Hamilton's optical method.
openaire +1 more source
Advanced Healthcare Materials, EarlyView.Myocardial infarction often leads to pathological remodelling and ventricular dilatation, key features of HFrEF. This study introduces a personalized, 3D‐printed cardiac restraint device (CARD) printed using rationally designed inks displaying the requested printability and mechanical properties.
Nicola Mansour +6 more
wiley +1 more source
Broadband Laser Doppler Frequency Shift Emulator for Satellite Laser Communication
IEEE Photonics Journal, 2019 A novel emulator of laser Doppler frequency shift (DFS) for satellite laser communication based on microwave photonics technology is proposed and experimentally demonstrated.
Jinye Li +6 more
doaj +1 more source
Analytical and experimental comparisons between the frequency-modulated–frequency-shift measurement and the pulsed-wave–time-shift measurement Doppler systems [PDF]
, 1996 In previous publications, a new echo-ranging Doppler system based on transmission of repetitive coherent frequency-modulated (FM) sinusoids in two different implementations was presented.
Pedersen, P. C., Wilhjelm, Jens Erik
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Frequency Spectrum of Doppler-shifted Whistler-mode Signals [PDF]
Nature, 1965 To further our knowledge of very-low-frequency signals received via the whistler mode of propagation we have constructed a 25-channel spectrum analyser. Other work1,2 has shown the existence of apparent Doppler shifts on these signals of up to two or three parts in 105 of the carrier frequency; but the equipment used did not allow the variations of ...
R. A. MORRIS, N. POLETTI
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Rapid Fabrication of Self‐Propelled and Steerable Magnetic Microcatheters for Precision Medicine
Advanced Materials, EarlyView.A rapid Joule heating fabrication method for the production of self‐propelling, adaptive microcatheters, with tunable stiffness and integrated microfluidic channels is presented. Demonstrated through three microrobotic designs, including a steerable guiding catheter, an untethered wave‐crawling TubeBot, and a distal‐end propelled microcatheter, it was ...
Zhi Chen +5 more
wiley +1 more source
TechnologiesSpace gravitational wave detection is performed via a laser interferometry system across hundreds of thousands to millions of kilometers for picometer-level displacement measurement, using phasemeters to read gravitational wave-induced displacement ...
Zhenbang Xie +3 more
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Modeling and analysis for dynamical Doppler shifts on terahertz communication signals propagating in inhomogeneous hypersonic plasma sheath [PDF]
AIP AdvancesPrevious studies have shown that terahertz (THz) signals could penetrate hypersonic plasma sheaths. Thus, it is considered to be a potential solution to the “blackout” problem.
Xiangmeng Lin +4 more
doaj +1 more source
Low-frequency Gravitational Wave Detection via Double Optical Clocks in Space [PDF]
, 2018 We propose a Doppler tracking system for gravitational wave detection via Double Optical Clocks in Space (DOCS). In this configuration two spacecrafts (each containing an optical clock) are launched to space for Doppler shift observations.
Jetzer, Philippe +3 more
core +2 more sources