Reconstructive tomography and applications to ultrasonics

Mueller, R. K.; Kaveh, M.; Wade, G.

doi:10.1109/proc.1979.11284

Cited by 366 publications

(93 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Further manipulation yields the so-called Porter-Bojarski integral equation [11] (6) where G; is the imaginary part of the free-space Green's function. Fourier transformation of this equation yields…”

Section: Reconstruction Algorithmmentioning

confidence: 99%

“…on the other hand, extract information about the geometric structure or contour of the interior parameters of a scatterer in a homogeneous environment from the wave-field obtained on the measurement surface. For diffraction sources such as ultrasound, the inverse scheme should be based on the wave equation rather than on the assumption of a straight line path from the source to the receiver as in X-ray tomography [5][6]. Based on the Born or Rytov approximation [7], diffraction tomography reconstructs the object function from the planar measurement of the displacement field by back-propagating the displacement to the full-space and summing over the frequency or over the different angles [8][9][10].…”

mentioning

confidence: 99%

See 1 more Smart Citation

A finite element test bed for diffraction tomography

1996

NDT & E International

View full text Add to dashboard Cite

Section: Reconstruction Algorithmmentioning

confidence: 99%

mentioning

confidence: 99%

A finite element test bed for diffraction tomography

1996

NDT & E International

View full text Add to dashboard Cite

“…However, the physical probe needs to be put in the temperature distribution, and the physical probe affects the temperature distribution. In contrast, non-contact measurement methods, which are called acoustical tomography method 1) or ultrasonic diffraction tomography method, 2) can obtain the temperature non-destructively from a sound velocity distribution which can be obtained without any physical contacts. The sound velocity distribution is reconstructed on the basis of propagation times on a number of sound paths.…”

Section: Introductionmentioning

confidence: 99%

Temperature Distribution Estimated by Optimization and Near-Field Acoustical Holography

et al. 2012

View full text Add to dashboard Cite

We propose a method to estimate temperature distribution non-destructively using combination of near-field acoustical holography (NAH) method and optimization method. NAH method is valid to calculate forward and back propagations of ultrasonic wave in a uniform medium. To estimate of temperature distribution, we proposed a modified method of NAH, called sectional NAH (SNAH), for using NAH in an inhomogeneous medium. In SNAH, a calculation space is discretized into a number of sections, so that the temperature in each section becomes nearly uniform, and NAH calculation is performed in each section. Calculation results using SNAH in the inhomogeneous medium well agreed with the calculation result using finite element method (FEM). By using SNAH, the temperature distribution is estimated as bellows. Firstly, sound fields, which are complex amplitude of harmonic oscillation, in three planes are measured. Next, sound field at one of measured plane is calculated from the other measured sound fields, which are calculated from other measurement planes using SNAH, with an initial sound velocity distribution. Then, difference between calculated and measured sound fields is minimized by optimizing the sound velocity distribution using multi-start downhill simplex method. In this method, a temperature distribution is obtained as the sound velocity distribution. In simulations, temperature distributions given as linear and Gaussian distributions were estimated. Validity of our proposal methods is confirmed by simulations.

show abstract

“…Clayton and Stolt, 1981, present a Born-WKBJ method to recover density and bulk modulus from reflection data. A slightly different approach to the direct inversion problem has been developed by extending x-ray tomographic techniques to ultrasonic imaging (Wolf, 1969, Mueller et. al., 1979and Devaney, 1984.…”

Section: Introductionmentioning

confidence: 99%

Tomographic methods for multidimensional born inversion with a wide-band source

Esmersoy¹,

Levy²

1985

SEG Technical Program Expanded Abstracts

View full text Add to dashboard Cite

Two methods for inverting the velocities of a multidimensional acoustic medium within the homogeneous Born approximation are presented. In both methods, the data is obtained by using a wide band source and an array.of receivers. The transmitted waves as well as the reflected waves are utilized for inversion. In the first method the medium is excited by a single point source and the scattered field is observed all around the medium. In the second method the medium is probed by a single plane wave (in some cases this can be viewed as the far field of a point source) and the scattered field is observed along a line receiver array. It is shown that, in both cases, the direct inversion problem can be reduced to a straight line tomography problem In the first method this is done by backpropagating the filtered and time-reversed traces into the medium and imaging the field at time zero. This zero time image provides the projections of the velocity function for all projection angles. Velocities are, then, obtained by the inverse Radon transform In the case of a plane wave source, it is shown that the slant-stack (Radon transform) of the observed traces along the receiver line is directly related to one projection of the velocity function. Different slant-stack slopes provide projections at different angles. For a single line receiver array, the projection angles cover a range of ninety degrees. The velocites can, therefore, be reconstructed partially in this case. For a complete set of projections either two receiver arrays on both sides of the medium, or two pane waves incident from opposite directions are required.-2-

show abstract

Reconstructive tomography and applications to ultrasonics

Cited by 366 publications

References 32 publications

A finite element test bed for diffraction tomography

A finite element test bed for diffraction tomography

Temperature Distribution Estimated by Optimization and Near-Field Acoustical Holography

Tomographic methods for multidimensional born inversion with a wide-band source

Contact Info

Product

Resources

About