Results 121 to 130 of about 37,725 (141)
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Effective impedance spectra for predicting rough sea effects on atmospheric impulsive sounds
The Journal of the Acoustical Society of America, 2005Two methods of calculating the effective impedance spectra of acoustically hard, randomly rough, two-dimensional surfaces valid for acoustic wavelengths large compared with the roughness scales have been explored. The first method uses the complex excess attenuation spectrum due to a point source above a rough boundary predicted by a boundary element ...
Patrice, Boulanger, Keith, Attenborough
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Coronary input impedance during cardiac cycle as determined by impulse response method
American Journal of Physiology-Heart and Circulatory Physiology, 1987The coronary arterial system was characterized by its input impedance determined in systole and diastole from impulse response functions in five dogs. The impulse response technique was verified on a known hydraulic system. A second confirmation was obtained on the circumflex artery: reflected pulses were correlated with site of reflections generated ...
G A, Van Huis, P, Sipkema, N, Westerhof
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[Diurnal profile of impulse oscillometric impedance in healthy subjects].
Pneumologie (Stuttgart, Germany), 1997Diurnal profiles of impulse oscillometry during 24 hours in 3 hour intervals in sitting and lateral lying position have been studied in 20 healthy female and male probands 10-67 years of age. Approximating the profiles by a sine-cosine-function the amplitude of resistance was found up to 3, that of reactance up to 1 hPa/l/s in single cases, preferably ...
J, Vogel +4 more
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2023 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting (USNC-URSI), 2023
Fernando Albarracin +3 more
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Fernando Albarracin +3 more
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A High-Impedance, Nanosecond Rise Time Probe for Measuring High-Voltage Impulses
IEEE Transactions on Power Apparatus and Systems, 1968Normal voltage dividers for high-voltage impulses are connected to the test object by an open air line which, when considered as part of the measuring system, gives an initially low input impedance to that measuring system due to the characteristic impedance of the line.
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Measurement of respiratory impedance by impulse oscillometry--effects of endotracheal tubes.
Research in experimental medicine. Zeitschrift fur die gesamte experimentelle Medizin einschliesslich experimenteller Chirurgie, 2001Impulse Oscillometry is a new, noninvasive method to measure respiratory impedance, i.e. airway resistance and reactance at different oscillation frequencies. These parameters are potentially useful for the monitoring of respiratory mechanics in the critically ill patent with respiratory dysfunction.
G E, Kuhnle +5 more
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Optimization of the Feed Impedance for an Arbitrary Crossed-Feed-ARM Impulse Radiating Antenna
2005Impulse radiating antennas (IRAs) are members of a class of antennas that are designed for the radiation of ultra-wideband (UWB) electromagnetic impulses. Through a combination of a non-dispersive transverse electromagnetic (TEM) feed structure and a focused aperture, IRAs act like differentiators for the early-time portion of the waveform.
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