Results 111 to 120 of about 40,549 (156)

An inverse hyperbolic integrodifferential problem arising in geophysics II

Nonlinear Analysis: Theory, Methods & Applications, 1990
See the review in Zbl 0771.45006.
Grasselli, M., Kabanikhin, S. I., Lorenzi, A.   +2 more
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Inverse Problems in Geophysics

1999
An important aspect of the physical sciences is to make inferences about physical parameters from data. In general, the laws of physics provide the means for computing the data values given a model. This is called the “forward problem”, see figure 1. In the inverse problem, the aim is to reconstruct the model from a set of measurements.
R. Snieder, J. Trampert
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Application of Neural Networks in Nonlinear Inverse Problems of Geophysics

Computational Mathematics and Mathematical Physics, 2020
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Obornev, E. A., Obornev, I. E., Rodionov, E. A., Shimelevich, M. I.   +3 more
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Model Parameterization and Model Selection in Geophysical Inverse Problems. Designing Inverse Problems that Respect a priori Geophysical Knowledge

2022
The vast majority of the Earth system is inaccessible to direct observation. Consequently, the structure and dynamics of the Earth can only be determined indirectly, via geophysical sensing. These methods have the mathematical form of an inverse problem, in which the data and the unknowns are linked by a physical process, such as seismic wave ...
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Scattering techniques for a one dimensional inverse problem in geophysics

Mathematical Methods in the Applied Sciences, 1981
AbstractA one dimensional problem for SH waves in an elastic medium is treated which can be written as vtt = A−1 (Avy)y, A = (ϱμ)1/2, ϱ = density, and μ = shear modulus. Assume A ϵ C1 and A′/A ϵ L1; from an input vy(t, 0) = ∂(t) let the response v(t, 0) = g(t) be measured (v(t, y) = 0 for t < 0).
R. Carroll, F. Santosa, L. Paynec
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Inverse scattering for geophysical problems. III. On the velocity-in version problems of acoustics

Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences, 1985
A bounded inhomogeneity D is immersed in an acoustic medium; the speed of sound is a function of position in D , and is constant outside. A time-harmonic source is placed at a point y and the pressure at a point x is measured.
Martin, P. A., Ramm, A. G.
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Nonlinear shaping regularization in geophysical inverse problems

SEG Technical Program Expanded Abstracts 2008, 2008
Shaping regularization is a general method for imposing constraints on the estimated model in the process of solving an inverse problem. In this paper, I extend the concept of shaping regularization to the case of nonlinear operators and show its connection to the nonlinear Landweber iteration and related iterative inversion methods.
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Computational methods for inverse problems in geophysics: inversion of travel time observations

Physics of the Earth and Planetary Interiors, 1980
Abstract General ways of solving various inverse problems are studied for given travel time observations between sources and receivers. These problems are separated into three components: (a) the representation of the unknown quantities appearing in the model; (b) the nonlinear least-squares problem; (c) the direct, two-point ray-tracing problem used
V. Pereyra, H.B. Keller, W.H.K. Lee
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Remarks on approximate methods in geophysical inverse problems

Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences, 1974
Several remarks are made on well-known methods used in geophysics to analyse inverse problems. Approximate values are given for Backus and Gilbert kernels, together with an integral equation which enables one to derive then from a Dirichlet kernel. Ways to obtain approximate expressions of the Dirichlet kernels are then studied.
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Two ways to quantify uncertainty in geophysical inverse problems

GEOPHYSICS, 2006
We present two approaches to invert geophysical measurements and estimate subsurface properties and their uncertainties when little is known a priori about the size of the errors associated with the data. We illustrate these approaches by inverting first-arrival traveltimes of seismic waves measured in a vertical well to infer the variation of ...
Alberto Malinverno, Robert L. Parker
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