A direct solution for radiative intensity with high directional resolution in isotropically scattering media

2018 ◽  
Vol 117 ◽  
pp. 296-302 ◽  
Author(s):  
Zhifeng Huang ◽  
Qiang Cheng ◽  
Chun Lou
Keyword(s):  
Direct Solution ◽  
Scattering Media ◽  
Radiative Intensity

Equation Solving DRESOR Method for Radiative Transfer in Three-Dimensional Isotropically Scattering Media

2014 ◽  
Vol 136 (9) ◽  
Author(s):  
Zhifeng Huang ◽  
Huaichun Zhou ◽  
Guihua Wang ◽  
Pei-feng Hsu
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Method ◽  
Computation Time ◽  
Discrete Ordinates ◽  
Distinct Advantage ◽  
Reverse Monte Carlo ◽  
Scattering Media ◽  
Equation Solving ◽  
Radiative Intensity ◽  
The Monte Carlo Method

Distributions of ratios of energy scattered or reflected (DRESOR) method is a very efficient tool used to calculate radiative intensity with high directional resolution, which is very useful for inverse analysis. The method is based on the Monte Carlo (MC) method and it can solve radiative problems of great complexity. Unfortunately, it suffers from the drawbacks of the Monte Carlo method, which are large computation time and unavoidable statistical errors. In this work, an equation solving method is applied to calculate DRESOR values instead of using the Monte Carlo sampling in the DRESOR method. The equation solving method obtains very accurate results in much shorter computation time than when using the Monte Carlo method. Radiative intensity with high directional resolution calculated by these two kinds of DRESOR method is compared with that of the reverse Monte Carlo (RMC) method. The equation solving DRESOR (ES-DRESOR) method has better accuracy and much better time efficiency than the Monte Carlo based DRESOR (original DRESOR) method. The ES-DRESOR method shows a distinct advantage for calculating radiative intensity with high directional resolution compared with the reverse Monte Carlo method and the discrete ordinates method (DOM). Heat flux comparisons are also given and the ES-DRESOR method shows very good accuracy.

Resolved Order of Scattering for the Solution of Radiative Transfer Equation

2013 ◽  
Vol 135 (4) ◽  
Author(s):  
Liangyu Wang ◽  
Robert J. Hall ◽  
Meredith B. Colket
Keyword(s):  
Radiative Transfer ◽  
Transfer Equation ◽  
Radiative Transfer Equation ◽  
Anisotropic Scattering ◽  
Scattering Media ◽  
Radiative Intensity ◽  
Reflecting Boundaries ◽  
Strong Scattering

The solution of the radiative transfer equation (RTE) becomes complicated when the participating medium is scattering and/or the boundary walls are reflecting. To reduce the complexity, the resolved order of scattering (ROS) formulation described in this paper separates the radiative intensities being solved by RTE into a series of intensities corresponding to different orders of the scattering and reflection events. The resulting equation of transfer for each order of radiative intensity is not only much simpler to solve but also represents the physical scattering/reflection processes that are hidden in the original full RTE. The ROS formulation provides a mathematically rigorous and elegant means of solving RTE for strong scattering media with or without reflecting boundaries. Sample calculations are presented for a droplet-laden, 3D enclosure with strong anisotropic scattering.

Anatomy and ultrastructure of haustoria in selected West Australian parasitic angiosperms

1990 ◽  
Vol 48 (3) ◽  
pp. 690-691
Author(s):  
John Kuo ◽  
John S. Pate
Keyword(s):  
Parasitic Plants ◽  
The Other ◽  
Nutrient Transfer ◽  
Direct Solution ◽  
Tracheary Elements ◽  
Solute Transfer ◽  
Glycol Methacrylate ◽  
Australian Species ◽  
Anatomy And Ultrastructure ◽  
Solution Transfer

Our understanding of nutrient transfer between host and flowering parasitic plants is usually based mainly on physiological concepts, with little information on haustorial structure related to function. The aim of this paper is to study the haustorial interface and possible pathways of water and solute transfer between a number of host and parasites.Haustorial tissues were fixed in glutaraldehyde and embedded in glycol methacrylate (LM), or fixed in glutaraldehyde then OsO4 and embedded in Spurr’s resin (TEM).Our study shows that lumen to lumen continuity occurs between tracheary elements of a host and four S.W. Australian species of aerial mistletoes (Fig. 1), and some root hemiparasites (Exocarpos spp. and Anthobolus foveolatus) (Fig. 2). On the other hand, haustorial interfaces of the root hemiparasites Olax phyllanthi and Santalum (2 species) are comprised mainly of parenchyma, as opposed to terminating tracheads or vessels, implying that direct solution transfer between partners via vessels or tracheary elements may be limited (Fig. 3).

Impact of Scattering on Transfer of Radiation in Emitting, Absorbing, and Scattering Media

2002 ◽  
Vol 33 (3-4) ◽  
pp. 4
Author(s):  
M. L. German ◽  
E. P. Nogotov ◽  
V. P. Necrasov
Keyword(s):  
Scattering Media

Imaging through Scattering Media with a Learning Based Prior

2020 ◽  
Vol 2020 (14) ◽  
pp. 306-1-306-6
Author(s):  
Florian Schiffers ◽  
Lionel Fiske ◽  
Pablo Ruiz ◽  
Aggelos K. Katsaggelos ◽  
Oliver Cossairt
Keyword(s):  
Optimization Problem ◽  
Autonomous Driving ◽  
Scattering Media ◽  
Photon Scattering ◽  
Point Spread ◽  
Spread Function ◽  
Radiative Transport Equation ◽  
Spatio Temporal ◽  
Transient Imaging

Imaging through scattering media finds applications in diverse fields from biomedicine to autonomous driving. However, interpreting the resulting images is difficult due to blur caused by the scattering of photons within the medium. Transient information, captured with fast temporal sensors, can be used to significantly improve the quality of images acquired in scattering conditions. Photon scattering, within a highly scattering media, is well modeled by the diffusion approximation of the Radiative Transport Equation (RTE). Its solution is easily derived which can be interpreted as a Spatio-Temporal Point Spread Function (STPSF). In this paper, we first discuss the properties of the ST-PSF and subsequently use this knowledge to simulate transient imaging through highly scattering media. We then propose a framework to invert the forward model, which assumes Poisson noise, to recover a noise-free, unblurred image by solving an optimization problem.

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