Results 211 to 220 of about 22,518 (261)

Surface acoustic impedance and causality

The Journal of the Acoustical Society of America, 2001
Several models that are commonly used to calculate the surface acoustic impedance of porous materials are examined in light of the causality requirement in its nonlocal and its approximate local forms. Strict (nonlocal) causality requires that the imaginary part of the surface acoustic impedance be the Hilbert transform of the real part.
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Acoustic Impedance from Motional Impedance Diagrams

The Journal of the Acoustical Society of America, 1948
When an acoustic load is coupled to an electromagnetic transducer through a length of air column, there is a critical length at which an increment in acoustic load produces a maximum increment in electrical impedance. The method described makes use of this critical coupling to obtain an optimum precision in determining an acoustical impedance.
R. D. Fay, J. E. White
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Acoustical impedance measurement.

The Journal of the Acoustical Society of America, 2008
Many components of specialty transducers have extremely tight acoustic impedance tolerances and become difficult to measure in a production environment. Comparing the device to the acoustical impedance of a cavity is one method of determining its acoustical impedance. A precise method of determining the acoustical impedance is described.
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A Wide Range Adjustable Acoustic Impedance

The Journal of the Acoustical Society of America, 1944
A method for obtaining a wide range of calculable impedance values has been developed. Three telescoping tubes are used, one being acoustically “infinite” in length. This “infinite” tube is used as a convenient, calculable impedance terminating the device.
Willard F. Meeker, Frank H. Slaymaker
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Tonndorf and acoustic impedance

The Journal of the Acoustical Society of America, 1990
Juergen was full of ideas that reflected his excellent understanding of the limits of technology and science. At first many of his ideas seemed impractical, but in my experience, he was usually right on target and got the results or data he was after. I learned many practice things from him in the lab; almost every encounter brought a new point of view
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Acoustic impedance estimation using calibration curve for scanning acoustic impedance microscope

2016 International Conference on Knowledge Creation and Intelligent Computing (KCIC), 2016
Ultrasonic has been used since several decades ago. One of ultrasonic application is used in medical field to observe mechanical properties of target, such as speed of sound, density, acoustic impedance, attenuation, etc. Several methods are also available to estimate mechanical property of target.
Agus Indra Gunawan, Yoshifumi Saijo, Naohiro Hozumi, Sachiko Yoshida, Kazuto Kobayashi, Seiji Yamamoto   +5 more
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Acoustic Impedance Inversion of VSP data

Proceedings, 2013
During the drilling stage, VSP plays an important role in predicting the depth of target strata and the lithologic characteristics of the deep strata ahead of the drill bit. Therefore, using VSP data to predict ahead of the drill bit has become a popular topic.
Jing Wang, Yanpeng Li, Jinling Du
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Acoustical Impedance of Enclosures

The Journal of the Acoustical Society of America, 1947
Formulas are derived for the acoustical impedance of three types of enclosures, a sphere, a cylinder, and a narrow rectangular box. The solutions are valid throughout the entire range from adiabatic to isothermal conditions.
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Acoustic Input Impedance of the Human Ear

Acta Oto-Laryngologica, 1966
An objective method of measuring the vibrations of the tympanic membrane by means of an improved capacitive-probe system is described. The device has a dynamic range up to 7500 A over the whole audiofrequency range. A new probe tip was developed, serving for conduction of the modulated H.F. signal as well as for the sound transmission.
H, Fischler, M, Hohenberger, E H, Frei, M, Rubinstein, D, Kretzer   +4 more
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Effect of the Acoustic Reflex on the Impedance at the Eardrum

Journal of Speech and Hearing Research, 1965
Seventeen ears of 12 subjects with normal hearing were tested in both a laboratory and a clinical setting to study impedance changes in normal human ears associated with the acoustic reflex. Compliance and resistance at the eardrum were measured with middle ear muscles relaxed and contracted by means of a contralateral noise stimulus, respectively.
A S, Feldman, J, Zwislocki
openaire   +2 more sources