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Ultra-low phase noise frequency combs
Frontiers in Optics 2015, 2015Emerging applications put increasing demands on the short-term stability of frequency combs. We review how ultra-low noise oscillator design combined with improved loop gain and bandwidth continue to enable these most challenging applications to date.
C.-C. Lee +3 more
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Ultra-Low Frequency Waves at Comets
2013Theory and observational results on ultralow frequency (ULF) waves or turbulence upstream of comets are reviewed. The ULF wave characteristics of comets Giacobini-Zinner and Halley are described and the cyclotron resonance condition is discussed. Theoretical work on the contribution of instabilities to ULF wave excitation is addressed. The quasi-linear
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Ultra-Low Frequency Seismic: Benefits and Solutions
International Petroleum Technology Conference, 2014Abstract Ultra-low seismic frequencies less than about 7–10 Hz cannot be produced with significant amplitudes by conventional air gun arrays, for any configuration and for any towing depth used during marine seismic surveys.
Andrew Samuel Long, Cyrille Reiser
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Ultra-wideband and low-frequency SAR interferometry
IGARSS '96. 1996 International Geoscience and Remote Sensing Symposium, 2002The authors analyse different techniques for 3D SAR mapping. Interferometry using narrow-band SAR enables retrieval of topography but gives an ambiguous height. Stereoscopy can also be used but has degraded resolution due to speckle. For ultra-wide band SAR, i.e.
L.M.H. Ulander, P.O. Frolund
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Performance of an ultra low-frequency folded pendulum
Physics Letters A, 1994Abstract A folded pendulum consisting of the sum of a conventional compound pendulum and an inverse pendulum can be tuned to create a pendulum with the dynamic response of a kilometre scale pendulum. Results are presented demonstrating the stability and Q-factor of the system down to a resonant frequency of 17 mHz.
David G. Blair +3 more
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High-sensitive ultra-low frequency hydrophone
International Conference on Micro- and Nano-Electronics 2018, 2019In this paper we demonstrate a new prototype of a high-precision ultra-low-frequency hydrophone on the basis of a planar type electrochemical transducer (ECT). We have developed a new planar electrochemical microchip and have invented a mechanical system that allows detecting the alternating pressure at low frequencies up to 0.01 Hz.
Vladimir G. Krishtop +6 more
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Adiabatic calorimeter as an ultra-low frequency spectrometer
Pure and Applied Chemistry, 1989Abstract
H. Suga, T. Matsuo
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Ultra-low-frequency ride motions and kinetosis
The Journal of the Acoustical Society of America, 1997Proposed ultra-high-speed ground transportation systems, such as Maglev, may have motion characteristics affecting passenger comfort different from anything previously experienced in ground transportation. These motions not only include isolated vertical maneuvers but also repeated motions.
E. D. Sussman +3 more
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Characteristics of Vacuo-Thermojunctions at Ultra-Low Frequency
IEEE Transactions on Instrumentation and Measurement, 1985Characteristics of vacuo-thermo-junctions (VTJ's) at ultra-low frequency are discussed. A method of expansion with series of nonharmonic sine functions has been combined with a method of perturbation to solve the partial differential equation for heat conduction in the heater of a vacuo-thermojunction.
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Ultra-low frequency dynamics in glassy crystals
Journal de Chimie Physique, 1985Enthalpy relaxation below and above the glass transition in an orientationally disordered crystal can be observed calorimetrically as a spontaneous temperature drift of the sample under an adiabatic condition. Upon the heating of a quenched sample, positive temperature drifts are observed to reach a peak at a temperature just below Tg and are followed
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