Magnetic Field Tomography: Theoretical Basis, Performance Measures and Limitations

An attempt is made in the paper to provide a satisfactory theoretical basis for a future discussion of the experimental data on the propagation of very long radio waves (18,800 m.) given by Best, Ratcliffe & Wilkes, and Budden, Ratcliffe & Wilkes. The reflexion of very long plane waves incident obliquely on a horizontally stratified ionized medium with a vertical magnetic field is first considered in general terms, and it is shown that the medium can be divided into a transition region and a reflecting region. If the ionization in the reflecting region increases linearly with height it is shown that propagation is governed by the following equations: ∂ 2 L / ∂ζ 2 + (α + ζ) L + β M = 0, ∂ 2 M / ∂ζ 2 + (α - ζ) M + β L = 0, where α and β are constants depending on the angle of incidence. Under the conditions of the experiments β is small, and a solution, in terms of contour integrals, valid in this case is obtained.

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Activation sequence of discrete brain areas during cognitive processes: results from magnetic field tomography

Electroencephalography and Clinical Neurophysiology ◽

10.1016/0013-4694(94)90125-2 ◽

1994 ◽

Vol 91 (5) ◽

pp. 399-402 ◽

Cited By ~ 23

Author(s):

A.A. Ioannides ◽

P.B.C. Fenwick ◽

J. Lumsden ◽

M.J. Liu ◽

P.D. Bamidis ◽

...

Keyword(s):

Magnetic Field ◽

Cognitive Processes ◽

Brain Areas ◽

Magnetic Field Tomography ◽

Activation Sequence

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Magnetic Field-Flow Fractionation: Theoretical Basis

Separation Science and Technology ◽

10.1080/01496398008068506 ◽

1980 ◽

Vol 15 (6) ◽

pp. 1297-1304 ◽

Cited By ~ 49

Author(s):

Thomas M. Vickrey ◽

Jaime A. Garcia-ramirez

Keyword(s):

Magnetic Field ◽

Theoretical Basis ◽

Field Flow Fractionation ◽

Flow Fractionation

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Experimental and theoretical basis of agricultural plant immunostimulation with regard to pathogenic fungi by magnetic field and He-Ne laser irradiation

10.1117/12.251192 ◽

1996 ◽

Author(s):

Alexey I. Belski ◽

Vadym D. Chivanov

Keyword(s):

Magnetic Field ◽

Laser Irradiation ◽

Theoretical Basis ◽

Pathogenic Fungi ◽

Agricultural Plant

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Detection of Interface Displacement of Liquid Metal Using Magnetic Field Tomography

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.402.326 ◽

2011 ◽

Vol 402 ◽

pp. 326-330

Author(s):

Shou Qiang Men ◽

Hong Bo Xiao ◽

Christian Resagk

Keyword(s):

Magnetic Field ◽

Sensor Array ◽

Fourier Transforms ◽

Interfacial Instabilities ◽

Direct Electric Current ◽

Aluminum Reduction ◽

Reduction Cell ◽

Interface Displacement ◽

Magnetic Field Tomography ◽

The Magnetic Field

Magnetic field tomography was applied to reconstruct the oscillating interface between liquid GaInSn alloy and aqueous KOH solution in a simplified cylindrical aluminum reduction cell. A direct electric current was imposed similar to the industrial reduction procedure, and a pneumatic shaker was used to excite interfacial instabilities with non-axisymmetric interface modes at the same time. The deformed interface led to a perturbation to the magnetic field which was measured by a sensor array. By fast Fourier Transforms, a database was generated and exploited to reconstruct the interface oscillation by solving an inverse problem.

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