Results 251 to 260 of about 6,980,177 (302)
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Flow, Turbulence and Combustion, 1998
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Spacecraft low-frequency residual acceleration
Journal of Spacecraft and Rockets, 1995An analytical model is described to calculate the low-frequency acceleration, which is intended to replace the rather crude estimations applied to analyze previous Spacelab missions. The three principal low-frequency perturbations of the Space Shuttle Orbiter are taken into account: atmospheric drag, gravity gradient (tidal effect), and spacecraft ...
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Electrical Engineering, 1931
The present status of joint development and research on low-frequency induction as it affects the closely associated circuits of the electric service and the communication utilities is outlined here.
R. N. Conwell, H. S. Warren
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The present status of joint development and research on low-frequency induction as it affects the closely associated circuits of the electric service and the communication utilities is outlined here.
R. N. Conwell, H. S. Warren
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Generalized frequency-sum beamforming for low frequencies
The Journal of the Acoustical Society of AmericaFor direction-of-arrival (DOA) estimation in the low-frequency range, we improve spatial resolution using generalized frequency-sum (gFS) beamforming with the Qth order frequency-sum autoproduct. The order Q does not exceed the maximum value, determined by the criteria that the sum of frequencies used to create the autoproduct must be less than the ...
Jeunghoon Lee +2 more
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High power very low frequency/low frequency transmitting antennas
IEEE Conference on Military Communications, 2002Very-low-frequency (VLF) and low-frequency (LF) transmitting antennas are small with respect to the wavelength and are required to radiate substantial power levels. Design parameters for these antennas are discussed, including the impact of technical advances in high-voltage design and bandwidth enhancement.
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Low-frequency, low-distortion digital quadrature oscillator
Journal of Physics E: Scientific Instruments, 1989Digital recursive and non-recursive filtering techniques have both been exploited to build a low-frequency (0.5-50 Hz), low-distortion digital quadrature oscillator. This generator shows an amplitude constant to within 0.3% over the frequency range, and the quadrature phase error is within +or-0.05 degrees .
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2012
The open loop and closed loop class-D amplifiers both opt for low frequency dithering for linearization, due to their high slope gain. They may opt for drain efficiency improvement, depending on their process technology, or intrinsic capacitance value.
Foad Arfaei Malekzadeh +2 more
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The open loop and closed loop class-D amplifiers both opt for low frequency dithering for linearization, due to their high slope gain. They may opt for drain efficiency improvement, depending on their process technology, or intrinsic capacitance value.
Foad Arfaei Malekzadeh +2 more
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1985
The object of this chapter is to examine some of the methods used to describe a plasma in the regime where collisional effects are important. For the most part we shall be looking at fluid theories, which give a good description of large-scale slow phenomena in a plasma, but are inadequate to describe the high-frequency waves and instabilities which ...
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The object of this chapter is to examine some of the methods used to describe a plasma in the regime where collisional effects are important. For the most part we shall be looking at fluid theories, which give a good description of large-scale slow phenomena in a plasma, but are inadequate to describe the high-frequency waves and instabilities which ...
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1999
Abstract The motivation for considering low frequency expansions is to replace the general scattering problems described in Chapter I by sequences of simpler problems. If one is interested only in scattering at extremely low frequencies, then, in the spirit of Rayleigh (1897a), it is possible to replace the scattering problem by a ...
George Dassios, Ralph Kleinman
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Abstract The motivation for considering low frequency expansions is to replace the general scattering problems described in Chapter I by sequences of simpler problems. If one is interested only in scattering at extremely low frequencies, then, in the spirit of Rayleigh (1897a), it is possible to replace the scattering problem by a ...
George Dassios, Ralph Kleinman
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Low Frequency Techniques Very Low Frequency Mechanical Spectroscopy
Materials Science Forum, 1993J. Woirgard, Andre Rivière
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