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Application of full‐wave inversion to real crosshole data
SEG Technical Program Expanded Abstracts 1994, 1994A 2.5D acoustic frequency domain fullwave inversion method was applied to a real dataset from an open-cast coal exploration site. The only data processing required was the removal of tube waves, because no shear wave arrivals were observed. The inversion is efficient because only a few frequency components are needed.
Zhong‐min Song, Paul R. Williamson
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Full wave 2.5D frequency domain inversion of real crosshole data
56th EAEG Meeting, 1994Seismic crosshole traveltime tomography, though robust and efficient, is limited in the resolution that it can achieve; attenuation tomography requires accurate knowledge of the velocity. Crosshole migration methods have better resolution but are generally non-quantitative.
Z. -M. Song +2 more
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Towards 3D full-wave inversion for GPR
2016 IEEE Radar Conference (RadarConf), 2016Full-wave inversion (FWI) for GPR is an imaging approach in which one tries to determine the parameters describing the subsurface (such as permittivity and permeability) which would best reproduce the observed data, via a non-linear least-squares optimisation problem.
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Full wave nonlinear inverse scattering for transmission breast imaging
The Journal of the Acoustical Society of America, 2006Ultrasound has been proposed as an adjunct diagnostic modality for 25+ years. However, initial studies were hampered by relatively low resolution. Over the past 20 years there has been a tremendous amount of research carried out in inverse scattering, the mathematical foundation behind quantitative determination of the coefficients of a partial ...
James Wiskin +2 more
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Full Wave Form 2.5D Inversion of Time Domain Induced Polarization
Proceedings, 2012According to the results this method of interpretation Time Domain IP is highly effective (Figure 1). It must be emphasized, that using IP parameters, such as decay time, give us new opportunity for interpretation.
A.E. Kaminsky +2 more
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Full Wave Inversion Using a Spectral-Element Discontinuous Galerkin Method
Proceedings, 2014We have developed a flexible Discontinuous Galerkin (DG) toolkit for full-wave inversion (FWI) that operates on unstructured non-affine meshes using a variety of element types (quadrilateral, triangular, hexahedral). The code handles spatially-variable polynomial-order across the mesh, and includes two approaches: modal DG with exact adjoints and ...
J.R. Krebs +7 more
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Full-Wave Inversion for Ocean Acoustical Tomography.
1997Abstract : This report describes a wave-equation based inversion method in layered medium with potential applications to ocean acoustical tomography. This method caters specifically to the strong depth-dependence of the problem by building inversion on top of a depth-dependent background, as opposed to on a homogeneous background in traditional ...
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Fast Three-Dimensional Full Wave Seismic Inversion using Source Encoding
72nd EAGE Conference and Exhibition - Workshops and Fieldtrips, 2010In this paper we will demonstrate that the computational effort of FWI can be reduced significantly by applying it to data formed by encoding and summing source gathers, if the encoding of the sources is changed between iterations. Changing the encoding between iterations changes the crosstalk noise caused by the summation of the sources.
J. R. Krebs +6 more
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Full wave frequency domain crosshole inversion and modelling in 2.5D
54th EAEG Meeting, 1992Several approaches to seismic wavefield inversion in a variety of contexts have been expounded over the last decade. In the frequency domain diffraction tomography (e.g . Devaney, 1984) appeared to offer very efficient imaging. It also held out the prospect of attenuation imaging in crosshole configurations without assuming any model of freqeuncy ...
Z. M. Song, P. R. Williamson
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Solving Full-Wave Nonlinear Inverse Scattering Problems by Deep Learning Schemes
2019 IEEE International Conference on Computational Electromagnetics (ICCEM), 2019This paper aims to solve a full-wave inverse scattering problem, which is a quantitative imaging problem, i.e., to reconstruct the permittivities of dielectric scatterers from the knowledge of measured scattering data. Scatterers are represented in pixel basis, which is a versatile approach since the value of permittivity of each pixel is an ...
Zhun Wei, Xudong Chen
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