Results 221 to 230 of about 21,775 (260)

Reconstruction of temperature distributions in a passive acoustic thermotomography

Proceedings IEEE International Symposium on Biomedical Imaging, 2003
Passive acoustic thermotomography is a method for measuring 2-D and 3-D temperature distributions deep inside biological objects using measurements of the objects own thermal acoustic radiation. Acoustic radiation, coming from deep within a body, is measured at 20 points on the surface and for every point the acoustic radiation is measured at a ...
V. I. Passechnik, K. M. Bograchev
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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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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 II, Chap. 25; T. S. Graham, PhD thesis, The Pennsylvania State University (Mar., 1969) (unpublished)] allowing visual observation of the wavefield to be studied.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 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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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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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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Acoustic source reconstruction in magnetoacoustic Imaging

2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC), 2016
Nano-sized particles are widely regarded as a tool to study biologic events at the cellular and molecular levels. However, only a few imaging modalities can visualize interaction between nanoparticles and living cells. A new method of functional imaging method is presented in this paper.
null Hongshuang Yang, null Shuai Zhang, null Xueying Zhang, null Guizhi Xu   +3 more
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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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Numerical reconstruction of apodized acoustical holograms

Journal of Sound and Vibration, 1976
Abstract Apodization is a process that was first used to improve the resolving power of imaging systems involving diffraction patterns. It originally signified a reduction in the energy in the side lobes, but it can also be used in a broader sense, as will be done here, to include either a reduction or an enlargement of the side lobes in an ...
D.B. Kramer, D.K. Anand
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