Cubic scattering coefficient in concentration in dense random media

1996 ◽  
Author(s):  
Sergio De Nicola
Keyword(s):  
Random Media ◽  
Scattering Coefficient

Accuracy of the Born approximation in calculating the scattering coefficient of biological continuous random media

2009 ◽  
Vol 34 (17) ◽  
pp. 2679 ◽  
Author(s):  
İlker R. Çapoğlu ◽  
Jeremy D. Rogers ◽  
Allen Taflove ◽  
Vadim Backman
Keyword(s):  
Born Approximation ◽  
Random Media ◽  
Scattering Coefficient

Viscoacoustic wave propagation in 2-D random media and separation of absorption and scattering attenuation

Geophysics ◽  
1995 ◽  
Vol 60 (2) ◽  
pp. 459-467 ◽  
Author(s):  
Guido Kneib ◽  
Serge A. Shapiro
Keyword(s):  
Wave Propagation ◽  
Random Media ◽  
Wave Amplitude ◽  
Travel Distance ◽  
Scattering Coefficient ◽  
Nonlinear Dependence ◽  
Scattering Attenuation ◽  
Coherent Field ◽  
The Mean ◽  
Seismic Amplitudes

Wave theoretical analysis of scalar, time‐harmonic waves propagating in a constant density medium with isotropic, random velocity fluctuations and being scattered mainly in the forward direction yields a simple and robust procedure that combines the logarithm of the mean wave amplitude with the mean logarithm of the wave amplitude to perform a separation of scattering attenuation and absorption effects. Finite‐difference simulations of wave propagation in 2-D random media with a Voigt‐body rheology illustrate the evolution of wave field fluctuations and demonstrate that the separation procedure works for a wide range of seismic albedos. In the case of no absorption, the logarithms of seismic amplitudes will have a nonlinear dependence on the travel distance if the wavefield fluctuations are small compared to the amplitude of the coherent field. If these fluctuations are large, the logarithms of seismic amplitudes will tend to constant levels independent of the travel distance. In the case of random viscoacoustic media and at propagation distances larger than the inverse of the scattering coefficient of the coherent field, and apart from geometrical spreading, the overall amplitude decrease will be predominated by absorption, even if the absorption coefficient is one order smaller than the scattering coefficient of the coherent field.

Random media with temperature controlled connectivity

1992 ◽  
Vol 2 (5) ◽  
pp. 503-510 ◽  
Author(s):  
F. Carmona ◽  
E. Valot ◽  
L. Servant ◽  
M. Ricci
Keyword(s):  
Random Media ◽  
Temperature Controlled

Investigation of particulate systems using optical pathlength spectroscopy

2000 ◽  
Vol 627 ◽  
Author(s):  
Gabriel Popescu ◽  
Aristide Dogariu
Keyword(s):  
Path Length ◽  
Random Media ◽  
Michelson Interferometer ◽  
Industrial Process ◽  
Optical Path Length ◽  
Industrial Applications ◽  
Optical Path ◽  
Interference Signal ◽  
Optical Length ◽  
Reference Mirror

ABSTRACTIn many industrial applications involving granular media, knowledge about the structural transformations suffered during the industrial process is desirable. Optical techniques are noninvasive, fast, and versatile tools for monitoring such transformations. We have recently introduced optical path-length spectroscopy as a new technique for random media investigation. The principle of the method is to use a partially coherent source in a Michelson interferometer, where the fields from a reference mirror and the sample are combined to obtain an interference signal. When the system under investigation is a multiple-scattering medium, by tuning the optical length of the reference arm, the optical path-length probability density of light backscattered from the sample is obtained. This distribution carries information about the structural details of the medium. In the present paper, we apply the technique of optical path-length spectroscopy to investigate inhomogeneous distributions of particulate dielectrics such as ceramics and powders. The experiments are performed on suspensions of systems with different solid loads, as well as on powders and suspensions of particles with different sizes. We show that the methodology is highly sensitive to changes in volume concentration and particle size and, therefore, it can be successfully used for real-time monitoring. In addition, the technique is fiber optic-based and has all the advantages associated with the inherent versatility.

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