Results 221 to 230 of about 28,996 (260)

Coupling Impedance of Cylindrical Tubes

IEEE Transactions on Electromagnetic Compatibility, 1972
The concept of a coupling (transfer) impedance as developed by Schelkunoff for cylindrical tubes is applied in the determination of the mutual coupling to a grounded coaxial cable. Formulas are developed utilizing the coupling impedance concept when the exciting, or interfering, circuit is either a single-wire line or another coaxial cable over a ...
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Comments on impedance tube measurements

The Journal of the Acoustical Society of America, 1981
The application of a new impedance measuring method to water-filled tubes is discussed. It is shown that source reflections do not invalidate the method, and that valid results can be obtained at frequencies several times higher than that of the first cross mode of the tube.
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Automation of impedance tube measurements

The Journal of the Acoustical Society of America, 1975
An apparatus is described that enables the automatic determination of impedance tube data, namely, the positions of the first two minima and the standing-wave ratios along the tube. Subject Classification: 85.20.
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Acoustic impedances of ear canals measured by impedance tube

2007
During hearing sensitivity tests, the sound field is commonly generated by an earphone placed on a subject ear. One of the factors that can affect the sound transmission in the ear is the acoustic impedance of the ear canal. Its importance is related to the contribution of other elements involved in the transmission such as the earphone impedance.
Ciric, Dejan, Hammershøi, Dorte
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Transverse Impedance of Two-Layer Tube

Proceedings of the 2005 Particle Accelerator Conference, 2006
The exact analytical expressions for the multipole longitudinal and transverse impedances of two-layer tube with finite wall thickness are obtained. The numerical examples for the impedances of the vacuum chamber with laminated walls are given.
M. Ivanyan, A.V. Tsakanian
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A two-microphone thermoacoustic impedance tube

The Journal of the Acoustical Society of America, 2000
An experimental arrangement has been developed to explore the thermoacoustic properties of stack materials. The apparatus may be viewed either as a thermoacoustic engine with two microphones mounted in the tube wall, or as a two-microphone impedance tube that accommodates thermoacoustic elements.
Timothy Simmons, Richard Raspet, Robert Hiller   +2 more
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Acoustic Impedance Tube - Two-microphone method [PDF]

Absorption of sound by acoustic materials is a critical issue for acoustical engineering. Applications included sound isolation, improving acoustical quality of room and buildingdesign. Knowing the acoustic properties of materials is important for designing such applications.
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The validity of the linear orifice impedance model for predicting the impedance of a tube

The Journal of the Acoustical Society of America, 1992
The orifice impedance model usually works well for modeling sound transmission through an orifice. However, for a long orifice or for an orifice with a large load impedance, the standard impedance model may be invalid. The goal of this paper is to establish when the orifice impedance model gives a valid estimate of the impedance of a tube in series ...
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The impedance of the neon discharge in a conical tube

Journal of Communications Technology and Electronics, 2011
The frequency dependence of the impedance of the neon discharge in a conical tube is measured. The measured curves depend on the direction of the discharge current. For the interpretation of such variations, we comprehensively study the discharge in the conical tube for both directions of the discharge current.
A. K. Muradov, T. Kh. Guseinov
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Impedance tube technology for flow acoustics

Journal of Sound and Vibration, 1981
Acoustic impedance of a termination, or of a passive subsystem, needs to be measured not only for acoustic lining materials but also in the exhaust systems of flow machinery, where mean flow introduces peculiar problems. Out of the various methods of measurement of acoustic impedance, the discrete frequency, steady state, impedance tube method [1] is ...
Panicker, VB, Munjal, ML
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