Results 241 to 250 of about 194,801 (292)

A Novel Approach to Newtonian Full-Wave Inversion

Geomodel 2021, 2021
Summary This paper is devoted to the frequency-domain full-waveform inversion by Newton’s method. We propose a new approach for calculating Newtonian corrections. In some cases, it is much more economical than the standard method based on solving a normal system of equations with a Hessian matrix.
M.S. Malovichko, A.N. Orazbayev, N. B. Yavich, N.I. Khokhlov   +3 more
openaire   +1 more source

Full Wave Inversion and Inverse Scattering in Ultrasound Tomography/Volography

2023
Ultrasound breast tomography has been around for more than 40 years. Early approaches to reconstruction focused on simple algebraic reconstructions and bent ray techniques. These approaches were not able to provide high-quality and high spatial-resolution images.
openaire   +2 more sources

Target-oriented Elastic Full Wave Form Inversion

Proceedings, 2012
A method for full wave form elastic inversion is presented. The method works target-oriented, by which we mean that the surface data is redatumed to the top of an objective sequence of appr. 500 m thickness, containing a reservoir with top and bottom seals.
A. Gisolf, P. M. van den Berg
openaire   +1 more source

SVD analysis of GPR full-wave inversion

Proceedings of the 15th International Conference on Ground Penetrating Radar, 2014
Full-wave inversion (FWI) is an imaging approach in which we find the quantitative subsurface parameters (such as the dielectric permittivity) which would best fit the recorded GPR data. This optimisation problem is nonlinear and ill-posed, and there have been numerous successes in applying FWI to GPR data.
Watson, F., Lionheart, W. R B
openaire   +1 more source

Ensemble Full Wave Inversion with Source Encoding

Proceedings, 2015
Full wave inversion (FWI) suffers from convergence toward local minima because of the inaccuracy of the initial model and the lack of low frequency data. Noises in seismograms further deteriorate the imaging quality. To relax the dependency on high quality low frequency data, we present an ensemble full wave inversion method with source encoding (EnFWI)
C. He, Y. Chen, H. Fu, G. Yang
openaire   +1 more source

Seismic Soundoff: A reality check on full-wave inversion

The Leading Edge, 2023
Öz Yilmaz returns to the podcast to highlight his award-winning article, “A reality check on full-wave inversion applied to land seismic data for near-surface modeling.”
openaire   +1 more source

2.5D Acoustic full-wave frequency-domain inversion

55th EAEG Meeting, 1993
Several approaches to frequency domain inversion and imaging have been developed over the last decade (e.g. Devaney, 1984; Pratt, 1989). These methods have typically been developed for 2D geometries and are accordingly limited by the implicit assumption of line sources.
Z. M. Song, P. R. Williamson, M. H. Worthington   +2 more
openaire   +1 more source

Imaging with multiples using linearized full-wave inversion

SEG Technical Program Expanded Abstracts 2012, 2012
The well-known multiple-removal tools such as deconvolution (in time, frequency, and slant-stack domains), Radontransform demultiple and frequency-wavenumber (f-k) demultiple are limited unless the geology of the subsurface is simple. In the presence of complex geology, multiples are not totally separable from primaries by criteria such as periodicity,
Mandy Wong, Biondo Biondi, Shuki Ronen
openaire   +1 more source

Compressive Sensing Applied to Full-wave Form Inversion

71st EAGE Conference and Exhibition incorporating SPE EUROPEC 2009, 2009
Full-waveform inversion's high demand on computational resources forms, along with the non-uniqueness problem, the major impediment withstanding its widespread use on industrial-size datasets.
F. J. Herrmann, Y. Erlangga, T. T. Y. Lin   +2 more
openaire   +1 more source

ON OBTAINING INITIAL APPROXIMATION FOR FULL WAVE INVERSION PROBLEM USING CONVOLUTIONAL NEURAL NETWORK

Доклады Российской академии наук. Математика, информатика, процессы управления, 2023
The paper considers the problem of choosing the initial approximation when using gradient optimization methods for solving the inverse problem of restoring the distribution of velocities in a heterogeneous continuous medium. A system of acoustic equations is used to describe the behavior of the medium, and a finite-difference scheme is used to solve ...
Petrov, I. B., Stankevich, A. S., Vasyukov, A. V.   +2 more
openaire   +2 more sources