Theory and application of wave propagation and scattering in random media

Abstract

S, = -(E, X z: ) = -lEJ2 o^ 2 2770and 770 = ( p~/ e o ) ' /~ is the characteristic impedance of the medium. We see that ud has the dimensions of area/solid angle. The dimensionless quantity p ( 8 , a in (2-2) is called the "phase function" and is commonly used in radiative transfer theory.' Ut is the "total cross section." In radar applications, the "bistatic radar cross section" ubi and the "backscattering cross section" Ob are often used. They are related t o ud through u&,n = 4n ~,(8,(76 is ah0 called the "radar cross section."Next, let us consider the total observed scattered power at all angles surrounding the particle. The cross section of a particle which would produce this amount of scattering is called the "scattering cross section." The scattering cross section us is given bywhere d o is the differential solid angle. The ratio W O of the scattering cross section to the total cross section is called the "albedo" of a single particle and is given byThe sum of the scattering and the absorption cross sections is called the "total cross section" U t or. the "extinction cross section," ut = 0, + 0,.(2-7) has no relation to the ''phase" of the wave. The name "phase function"The "phase function" represents the amount of scattered power and has its origins in astronomy, where it refers to lunar phases.

Two dimensional mapping of the perfusion of the retina and optic nerve head.

“…With the calculated data of flow (equation (5)), volume (equation (6)), and. velocity (equation (7) Figure 6 shows schematically the principle of function of SLDF.…”

Physical explanation of the SLIPI technique by the large scatterer approximation of the RTE

“…The analysis reviewed in this section follows Ishimaru closely [12, Chapter 13] and [15]. An electrically large object scatters strongly in the forward direction, and less in all other directions.…”

Towards Conformal Interstitial Light Therapies: Modelling Parameters, Dose Definitions and Computational Implementation

“…It is spectrally dependent for a given chromophore, and for a given tissue may be represented as µ a (λ) = ∑ ǫ i (λ i )C i , where ǫ i and C i are the extinction coefficient and concentration, respectively, for chromophore i in the tissue. The radiative transport equation (RTE) (Ishimaru, 1977) is a description of photon transport through a medium, derived from conservation of energy:…”