Results 301 to 310 of about 96,792 (346)

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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Acoustic impedance of the maternal abdomen

The Journal of the Acoustical Society of America, 1993
Contact sensors to monitor fetal heart, breathing, and movement sounds with increased sensitivity and bandwidth are under development. To understand the inherent acoustical properties of the maternal abdomen and its interaction with these sensors, the driving-point impedance Z(jω) was measured in nine women during their last trimester of pregnancy.
G R, Wodicka, A M, Lam, V, Bhargava, D, Sunkel   +3 more
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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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Active acoustical impedance using distributed electrodynamical transducers

The Journal of the Acoustical Society of America, 2006
New miniaturization and integration capabilities available from emerging microelectromechanical system (MEMS) technology will allow silicon-based artificial skins involving thousands of elementary actuators to be developed in the near future. SMART structures combining large arrays of elementary motion pixels coated with macroscopic components are thus
M, Collet, P, David, M, Berthillier
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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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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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Measurement of Acoustic Impedance

The Journal of the Acoustical Society of America, 1948
In this paper a method is described of measuring the acoustic impedance of a sample of material forming one boundary of a shallow cylindrical cavity, by determining the sound pressure produced when a known volume current is injected into the cavity from a high impedance source. The volume current is effectively determined by observing the pressure when
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Acoustic Impedance of Sample from Motional Impedance Diagrams

The Journal of the Acoustical Society of America, 1948
If the electrical impedance of an electromagnetic speaker is plotted as a vector when the acoustic loading consists of an air column of variable length terminated by a rigid plug, a circle diagram results. If the air column is terminated instead by an acoustic sample, a second circle diagram results.
R. D. Fay, J. E. White
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A Method of Measuring Acoustic Impedance

The Journal of the Acoustical Society of America, 1932
An apparatus s described whereby acoustic impedances may be measured in terms of a known acoustic impedance and the complex ratios of two electrical potentiometer readings to a third. As a known impedance, there is chosen the reactance of a closed tube of uniform bore which is an eighth wave-length long.
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Acoustic Neuromas and the Acoustic Impedance of the Ear

Journal of Speech and Hearing Disorders, 1973
The acoustic impedance at the tympanic membrane was measured at frequencies in the range 100–1000 Hz and found to be abnormal on the affected side in four patients with acoustic neuroma. In all four the resistance was abnormally high at low frequencies on the affected side, and in three the reactance of the affected ear was raised relative to that of ...
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