Iterative methods for tomography problems: implementation to a cross-well tomography problem

Download

Karadeniz_2018_IOP_Conf._Ser.__Mater._Sci._Eng._300_012060.pdf

Date

2017-08-23

Author

Karadeniz, M. Fatih
Weber, Gerhard Wilhelm

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

149
views

74
downloads

The velocity distribution between two boreholes is reconstructed by cross-well tomography, which is commonly used in geology. In this paper, iterative methods, Kaczmarz's algorithm, algebraic reconstruction technique (ART), and simultaneous iterative reconstruction technique (SIRT), are implemented to a specific cross-well tomography problem. Convergence to the solution of these methods and their CPU time for the cross-well tomography problem are compared. Furthermore, these three methods for this problem are compared for different tolerance values.

URI

https://hdl.handle.net/11511/57619

DOI

https://doi.org/10.1088/1757-899x/300/1/012060

Conference Name

4th International Conference on Operational Research (InteriOR)

Collections

Graduate School of Applied Mathematics, Conference / Seminar

Suggestions

OpenMETU
Core

Incompressible flow simulations using least squares spectral element method on adaptively refined triangular grids Akdağ, Osman; Sert, Cüneyt; Department of Mechanical Engineering (2012) The main purpose of this study is to develop a flow solver that employs triangular grids to solve two-dimensional, viscous, laminar, steady, incompressible flows. The flow solver is based on Least Squares Spectral Element Method (LSSEM). It has p-type adaptive mesh refinement/coarsening capability and supports p-type nonconforming element interfaces. To validate the developed flow solver several benchmark problems are studied and successful results are obtained. The performances of two different triangular ...
Parameter sensitivity analysis of a nonlinear least-squares optimization-based anelastic full waveform inversion method Askan Gündoğan, Ayşegül; Bielak, Jacobo; Ghattas, Omar (Elsevier BV, 2010-07-01) In a recent article, we described a seismic inversion method for determining the crustal velocity and attenuation of basins in earthquake-prone regions. We formulated the problem as a constrained nonlinear least-squares optimization problem in which the constraints are the equations that describe the forward wave propagation. Here, we conduct a parametric study to investigate the influence of parameters such as the form of the regularization function, receiver density, preconditioning, noise level of the da...
Nested and robust modeling techniques for fNIRS data with demographics and experiment related factors in n-back task Çakar, Serenay; Gökalp Yavuz, Fulya (2022-01-01) Functional near-infrared spectroscopy (fNIRS) signals are used to measure relative changes in oxyhemoglobin (HbO) and deoxyhemoglobin (HbR) concentrations. Brain response studies constitute multilevel or nested datasets formed by different parts of the brain of individuals and multidimensional datasets. The changes in brain activities under specific stimuli are investigated with the help of statistical analysis. However, these studies ignore the dependence structure between the repeated measures of the same...
Numerical Simulation of Rarefied Laminar Flow past a Circular Cylinder Çelenligil, Mehmet Cevdet (2014-07-18) Numerical simulations have been obtained for two-dimensional laminar flows past a circular cylinder in the transitional regime. Computations are performed using the direct simulation Monte Carlo method for Knudsen numbers of 0.02 and 0.2 and Mach numbers of 0.102 and 0.4. For these conditions, Reynolds number ranges from 0.626 to 24.63 and the flows are steady. Results show that separation occurs in the wake region for the flow with Mach number of 0.4 and Knudsen number of 0.02, but for the other eases flow...
Excitation spectrum of Hubbard model with infinite electron repulsion on strip-type triangular lattices Cheranovskii, VO; Ezerskaya, EV; Krikunov, MV (2001-02-05) The estimations of the stability region of the lattice ferromagnetic ground state in the space of model parameters are found. For the triangular lattice strip formed by L segments with the total number of electrons N = L + 1 we derived the effective Hamiltonians describing the low-energy states of the strips and obtained the analytical estimations for above stability region. The possibility of the magnetic transition with the jump of the ground-state spin between minimal and maximal values has also been sho...

Citation Formats

M. F. Karadeniz and G. W. Weber, “Iterative methods for tomography problems: implementation to a cross-well tomography problem,” Medan, INDONESIA, 2017, vol. 300, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/57619.