Results 261 to 270 of about 127,881 (313)

Acoustic measurement of the respiratory system— An acoustic pneumograph

Medical & Biological Engineering, 1976
A 200 Hz tone from a sinewave generator was utilised to monitor respiration. The sound was led into the lung from the mouth and the transmitted sound was detected through the thoracic cage by a phonocardiogram microphone fixed on the chest wall. The microphone output voltage, represented by its absolute mean value, varied with the respiration of the ...
M, Miyakawa, K, Yamamoto, T, Mikami
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Progress in Measurements in Acoustics

Metrologia, 1967
Although the speed of sound in air was measured with reasonable accuracy about the middle of the 17th century, intensity measurements did not properly begin until Rayleigh, in 1882, published his experiments with what came to be called the Rayleigh disc. The accuracy remained relatively low (about 10%) until about 1940.
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Simplified Room Acoustic Measurements

The Journal of the Acoustical Society of America, 2008
Standardised room acoustic measurements are needed for concert halls etc., but they imply heavy equipment. Thus, many interesting rooms are not measured. Most musicians (and even some acousticians) find that clapping and shouting in a room/hall might give an overview of the room acoustics.
T HALMRAST, A BUEN
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Acoustic Measurements of Objective Tinnitus

Journal of Speech, Language, and Hearing Research, 1990
Ear canal sound pressure levels were measured from a 38-year-old woman who had experienced objective tinnitus in her right ear for approximately 2 years. The tinnitus sounded like a series of “sighs” that were synchronous with her pulse rate. Because the level of the tinnitus fluctuated in a pulsing manner, it appeared to be of vascular origin ...
C A, Champlin, S P, Muller, S A, Mitchell   +2 more
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Acoustic measurement of erythrocyte compressibility

The Journal of the Acoustical Society of America, 1982
Adiabatic compressibility of red blood cells obtained from humans using a modified ultrasound velocity technique has been determined and correlated to the mean cellular hemoglobin concentration of the red blood cells. The ultrasound technique has an accuracy of better than 0.1%.
K K, Shung, B A, Krisko, J O, Ballard
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Interlaboratory Acoustic Power Measurement

Journal of Ultrasound in Medicine, 2003
This article describes an American Institute of Ultrasound in Medicine-sponsored intercomparison of the results of acoustic power measurements performed by several laboratories.Two primary calibration techniques, namely, planar scanning and radiation force balance, were used in the frequency range typical of that in which sonographic imaging devices ...
Peter A, Lewin, Nadine, Barrie-Smith, Masao, Ide, Kullervo, Hynynen, Michael, Macdonald   +4 more
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Accuracy of Acoustic Rhinometry Measurements

The Laryngoscope, 2001
AbstractObjectives To identify the factors that influence the accuracy of acoustic rhinometry measurements recorded with commercially available equipment.Study Design A simple model was used which consisted of a metal pipe and cylindrical inserts. These inserts comprised various lengths, and aperture dimensions were comparable to, or smaller than, the ...
O, Cakmak, H, Celik, T, Ergin, L, Sennaroglu   +3 more
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Acoustic Measurements of Articulator Motions

Phonetica, 1979
Abstract Methods for estimating articulatory data from acoustic measurements are reviewed. First, relations between the vocal-tract area function and formant or impedance data are pointed out. Then the possibility of determining a (discretized) area function from the speech signal itself is considered.
M R, Schroeder, H W, Strube
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Acoustic Measurement of Subglottic Stenosis

Annals of Otology, Rhinology & Laryngology, 1996
A device that determines cross-sectional area (CSA) of the airway by acoustic ref lections (Hood, Inc) was used to measure subglottic area. Airway models were made from Plexiglas rings with known internal dimensions similar to clinically encountered stenoses of various lengths and diameters.
J M, Czaja, T V, McCaffrey
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Acoustic characteristics of stethophonendoscopes and their measurement

Biomedical Engineering, 1972
1. The method that has been described takes account of the patient-stethophonendoscope-doctor system.
B E, Votchal, L A, Vodolazskiĭ, B A, Golikov   +2 more
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