Results 41 to 50 of about 14,116,486 (379)
Metrology and Measurement Systems, 2020 The possibilities to improve values of the satellite orbit elements by employing the pseudo-ranges and differences of carrier phase frequencies measured at many reference GPS stations are analysed. An improvement of orbit ephemeris is achieved by solving
Skeivalas Jonas +3 more
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Post-Newtonian Theory for Precision Doppler Measurements of Binary Star Orbits [PDF]
, 1999 The determination of velocities of stars from precise Doppler measurements is described here using relativistic theory of astronomical reference frames so as to determine the Keplerian and post-Keplerian parameters of binary systems.
Brumberg V. A. +16 more
core +3 more sources
A New Approach for Testing Fetal Heart Rate Monitors
Sensors, 2020 In this paper, a new approach for the periodical testing and the functionality evaluation of a fetal heart rate monitor device based on ultrasound principle is proposed.
Daniele Bibbo +10 more
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Modeling of Monopulse Radar Signals Reflected from Ground Clutter in a Time Domain Considering Doppler Effects [PDF]
Journal of Electromagnetic Engineering and Science, 2020 To evaluate the performance of a monopulse radar system, it is necessary to accurately model radar return signals from the ground surface in a time domain.
Jeong-Hun Nam +4 more
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Non-invasive Ultrasound Doppler Effect Based Method of Liquid Flow Velocity Estimation in Pipe [PDF]
Archives of Acoustics, 2023 This paper discusses the estimation of flow velocity from a multi-sensor scenario. Different estimation methods were used, which allow the effective measurement of the actual Doppler shift in a noisy environment, such as water with air bubbles, and on ...
Pawel Biernacki +2 more
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Orbital angular momentum complex spectrum analyzer for vortex light based on the rotational Doppler effect. [PDF]
Light Sci Appl, 2017 The ability to measure the orbital angular momentum (OAM) distribution of vortex light is essential for OAM applications. Although there have been many studies on the measurement of OAM modes, it is difficult to quantitatively and instantaneously measure
Zhou HL +7 more
europepmc +2 more sources
Theory of Dicke narrowing in coherent population trapping [PDF]
, 2007 The Doppler effect is one of the dominant broadening mechanisms in thermal vapor spectroscopy. For two-photon transitions one would naively expect the Doppler effect to cause a residual broadening, proportional to the wave-vector difference.
A. Ben-Kish +7 more
core +2 more sources
Superlight inverse Doppler effect [PDF]
Nature Physics, 2018 It has long been thought1 that the inverse Doppler frequency shift of light2–13 is impossible in homogeneous systems with a positive refractive index.
Xihang Shi +7 more
semanticscholar +2 more sources
Doppler-Induced Dynamics of Fields in Fabry-Perot Cavities with Suspended Mirrors [PDF]
, 2001 The Doppler effect in Fabry-Perot cavities with suspended mirrors is analyzed. Intrinsically small, the Doppler shift accumulates in the cavity and becomes comparable to or greater than the line-width of the cavity if its finesse is high or its length is
Abramovici +6 more
core +3 more sources
地震科学进展, 2021 A magnitude M7.8 earthquake struck Kermadec Island，New Zealand on March 5，2021. In this study we determined surface wave magnitude using 692 stations from USGS global networks and 112 stations from China global earthquake monitoring system，then analyzed ...
Wenze Deng
doaj +1 more source