Results 271 to 280 of about 1,359,591 (313)

Wavefield Reconstruction and Acoustic Holography

The Journal of the Acoustical Society of America, 1972
Acoustic holography has been shown to be a useful tool for studying single frequency acoustic wavefields [Acoustical Holography (Plenum Press;, New York, 1969), Vol. II, Chap. 25; T. S. Graham, PhD thesis, The Pennsylvania State University (Mar., 1969) (unpublished)] allowing visual observation of the wavefield to be studied.
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Acoustic source reconstruction and visualization based on acoustic radiation modes

Journal of Sound and Vibration, 2018
Abstract Fourier-based Nearfield Acoustical Holography (NAH), Statistically Optimized Nearfield Acoustical Holography (SONAH) and the Equivalent Source Method (ESM) are widely used in noise source identification and as important tools to guide design modification for noise control purposes. Fourier transform-based NAH requires the sound field to fall
Jiawei Liu, Yangfan Liu, J. Stuart Bolton   +2 more
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Reconstructive acoustic thermotomography of biological objects

Radiophysics and Quantum Electronics, 1997
An algebraic reconstructive tomography algorithm for mapping the internal temperature field in q section of a biological object is adapted for use in a multichannel scanning acoustic thermotomograph. For some types of thermodynamic temperature distribution, using the computer simulation method, the distributions of the acoustic brightness temperature ...
S. Yu. Ksenofontov, A. D. Mansfeld, A. M. Reyman   +2 more
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The accuracy of acoustic reconstructions of lightning channels

Journal of Geophysical Research, 1974
The effects of wave front curvature, wind, and temperature on the determination of the direction of propagation of thunder at an array of microphones is examined, and it is shown that the direction of propagation can be measured at the array with an error of less than ±1° under the following conditions: the wind velocity at the array should be measured
A. A. Few, Thomas L. Teer
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Acoustic tube reconstruction from noncausal excitation

IEEE Transactions on Acoustics, Speech, and Signal Processing, 1987
Algorithms and experimental procedures are presented for the reconstruction of the area function of a nonuniform tube. This reconstruction is performed from acoustics measurements that are taken in response to acoustic excitation of the tube at one end. The novel aspect of the procedure is that it is applicable to the case where the excitation waveform
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New Calculational Method for Acoustic Reconstructing

2009 International Forum on Information Technology and Applications, 2009
A new calculational method for acoustic reconstructing is proposed based on ellipsoidal acoustic infinite element method. Firstly, the entire acoustic field in ellipsoidal coordinate is divided by some infinite domains, and every domain has some nodes. Then pressure functions are determined by requiring the assumed-form solution to satisfy the pressure
Ma Fuqin, Gao Long, Song Gaoju
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Criteria for the resolution and reconstruction of acoustic impedance

Journal of Geophysical Research: Solid Earth, 1983
We derive approximate quantitative criteria for the resolution and reconstruction of the acoustic impedance for horizontally stratified media calculated from band‐limited seismic data both without and with noise. The first criterion, for noise‐free data, relates the calculated acoustic impedance to the true acoustic impedance using only the DC (zero ...
Philip M. Carrion, Waldo A. Patton
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Acoustical Holograms and Optical Reconstruction

1969
Theoretical and experimental investigations of the construction of acoustical holograms and the optical reconstruction of their images are described. The matrix representation of Gabor’s hologram is presented, and the matrix method is used to analyze the experimental results obtained.
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Reconstruction of Clipped Waveforms in Acoustic Emissions

Geophysical Prospecting
ABSTRACT Acoustic emission (AE) is elastic waves generated spontaneously from the creation of micro‐cracks. AE waveforms share significant similarities with microseismic signals and serve as an effective tool for improving the understanding of fracture processes during hydraulic fracturing.
Shaojiang Wu, Yibo Wang, Yue Ma
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Acoustic Application of Phase Reconstruction Algorithms in Optics

ICASSP 2022 - 2022 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 2022
Tomoki Kobayashi, Tomoro Tanaka, Kohei Yatabe, Yasuhiro Oikawa   +3 more
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