Filters








88,048 Hits in 6.2 sec

Efficient Rendering of Human Skin [article]

Eugene D'Eon, David Luebke, Eric Enderton
2007 Symposium on Rendering  
We show that sums of Gaussians provide an accurate approximation of translucent layer diffusion profiles, and use this observation to build a novel skin rendering algorithm based on texture space diffusion  ...  Existing offline techniques for modeling subsurface scattering effects in multi-layered translucent materials such as human skin achieve remarkable realism, but require seconds or minutes to generate an  ...  Chris Cowan was extremely helpful in preparing all this data for real-time rendering. Thanks to Craig Donner, Henrik Wann Jensen and George Borshukov for answering many questions about their work.  ... 
doi:10.2312/egwr/egsr07/147-157 fatcat:pa6d4bbajnd7jglov6ln2bhnmu

Derivation of an Improved Semi-empirical Expression for the Re-ionisation Background in Low Energy Ion Scattering Spectra [article]

H. R. Koslowski, Ch. Linsmeier
2021 arXiv   pre-print
Low energy ion scattering is a technique to detect the energy of ions which are scattered from a surface.  ...  In a previous work a semi-empirical formula has been given which allows fitting and derivation of quantitative information from the measured spectra [Nelson 1986 J. Vac. Sci. Technol. A 4 1567-1569].  ...  Again, the sum of all considered contributions (full line) gives a very good representation of the measured data.  ... 
arXiv:2109.02546v1 fatcat:2z7jwmvelzgwjbkc4olvrxihre

Interpreting photometry of regolith-like surfaces with different topographies: shadowing and multiple scattering

Yuriy G. Shkuratov, Dmitriy G. Stankevich, Dmitriy V. Petrov, Patrick C. Pinet, Aurélien M. Cord, Yves H. Daydou, Serge D. Chevrel
2005 Icarus (New York, N.Y. 1962)  
Multiple scattering between different parts of a rough surface suppresses the effect of shadowing, thus the effects produced by increases in albedo on the photometric behavior of a surface can be compensated  ...  The computer modeling shows that rocky topographies generated by randomly distributed stones over a flat surface reveal much steeper phase curves than surface with random topography generated from Gaussian  ...  This study was partially supported by INTAS Grant #2000-0792 and by the French National Program of Planetology (PNP/INSU/CNRS).  ... 
doi:10.1016/j.icarus.2003.12.017 fatcat:j5xa4pke5bdhtmiwpsdqny3p6m

Analytical fitting model for rough-surface BRDF

Ingmar G. E. Renhorn, Glenn D. Boreman
2008 Optics Express  
Using the FindFit function in Mathematica, the functional form is fitted to BRDF measurements over a wide range of incident angles.  ...  A physics-based model is developed for rough surface BRDF, taking into account angles of incidence and scattering, effective index, surface autocovariance, and correlation length.  ...  Fitting of experimental data to the analytical model The total scattered radiation is modeled as the BRDF given above, which is a highly nonlinear function of the fitting parameters and variables.  ... 
doi:10.1364/oe.16.012892 pmid:18711528 fatcat:wdt7723hu5ayrhmpn6gic6fl7y

Surface Approximation to Scattered Lines

A. Ardeshir Goshtasby
2007 Computer-Aided Design and Applications  
To fit a surface to the new set of lines, instead of using a Gaussian of a fixed height Z i , we let the height of the Gaussian vary with data along the line.  ...  The proposed method can, in general, be used to fit a surface to scattered lines.  ... 
doi:10.1080/16864360.2007.10738548 fatcat:chbxbh2fffdrnmiczpz4e536py

SoftWAXS: a computational tool for modeling wide-angle X-ray solution scattering from biomolecules

Jaydeep Bardhan, Sanghyun Park, Lee Makowski
2009 Journal of Applied Crystallography  
Numerical results illustrate the differences between this approach to modeling the excluded volume and a widely used model that treats the excluded-volume function as a sum of Gaussians representing the  ...  This paper describes a computational approach to estimating wide-angle X-ray solution scattering (WAXS) from proteins, which has been implemented in a computer program calledSoftWAXS.  ...  This work was supported by a EUREKA grant from the National Institutes of Health (grant No. R01-GM085648).  ... 
doi:10.1107/s0021889809032919 pmid:21339902 pmcid:PMC3041499 fatcat:wezdbazs25hjjhgp7sd6g6dsoa

Thermally induced disorder on a Cu(110) surface studied by low-energy ion scattering and inverse photoemission

Th. Fauster, R. Schneider, H. Dürr, G. Engelmann, E. Taglauer
1987 Surface Science  
Taking scattering by defects into account gives a good fit of the experimental data.  ...  The scattering of low-energy Na + ions (600 eV, ,9 = 50 o) off a Cu(ll0) surface along the [110] azimuthal direction shows a strong decrease of the intensity above 450 K.  ...  We also would like to thank S. Kato for help during the Na § ion scattering experiments and D.P. Jackson for the ARGUS calculations.  ... 
doi:10.1016/s0039-6028(87)80488-0 fatcat:zpfkj2tgojgnlpks2advlfyuwu

Fitting EXAFS data using molecular dynamics outputs and a histogram approach

Stephen W. T. Price, Nicholas Zonias, Chris-Kriton Skylaris, Timothy I. Hyde, Bruce Ravel, Andrea E. Russell
2012 Physical Review B  
Each bin from the histogram was considered to be a single scattering path and subsequently used in fitting the EXAFS data obtained for a series of carbon-supported platinum nanoparticles.  ...  In addition, the surface atoms of nanoparticles have been observed to undergo a greater contraction than those in the core, further increasing the range of bond distances.  ...  N.Z. would like to thank the Southampton Nanoforum for a PhD studentship. C.K.S would like to thank the Royal Society for a University Research Fellowship.  ... 
doi:10.1103/physrevb.85.075439 fatcat:xtx6j4xpefbwvaizi4wxhsqewe

Subsurface scattering using splat-based diffusion in point-based rendering

Hyeon-Joong Kim, Bernd Bickel, Markus Gross, Soo-Mi Choi
2010 Science China Information Sciences  
Keywords subsurface scattering, point-based rendering, skin rendering, diffusion profile, sum of Gaussian Citation Kim H J, Bickel B, Gross M, et al.  ...  To accurately simulate subsurface scattering in multilayered materials, we present splat-based diffusion to apply a linear combination of several Gaussian basis functions to each splat in object space.  ...  Since the diffusion profiles can be measured by analyzing scattering of laser or structured light patterns, any translucent object can be represented through the process of fitting a sum-of Gaussian to  ... 
doi:10.1007/s11432-010-0068-y fatcat:gsiijlbzmvfrph45h5qx46qjqm

Hydrogen molecule-antihydrogen atom potential energy surface and scattering calculations

Barry Peter Mant, Mark McGregor Law, Krzysztof Strasburger
2019 Journal of Physics B: Atomic, Molecular and Optical Physics  
Rigid-rotor scattering calculations on these surfaces have been carried out using the S-matrix Kohn variational method with a two-dimensional Gaussian basis set.  ...  The energies have been fit to functional forms using a neural network for the short-range interaction which is combined with asymptotic formulas at long range.  ...  This paper is dedicated to the memory of John H Binks (1932-2011).  ... 
doi:10.1088/1361-6455/ab312e fatcat:mt2fgigfvfcipopinxsmb4duyy

A Note on the Radial Shape of Isospin Potential

H. M. Sen Gupta, D. Husain, M. Rahman, M. Musa
1971 Progress of theoretical physics  
It has been pointed out by Lane 1 > that such a term arises .in the calculation of potential considered as a sum of two-body interaction with Heisenberg component and averaged over a Fermi gas.  ...  While previous analyses usually favoured a surface-centred Gaussian shape, the present work in contrast indicates that the choice of form factor is probably not important (only in 59 Co, a Gaussian shape  ... 
doi:10.1143/ptp.45.971 fatcat:sjm77ffw2vd4xiqe4s5cjh6i7a

Surface self-diffusion at intermediate temperature: The Ag(110) case

L. Pedemonte, R. Tatarek, G. Bracco
2002 Physical Review B (Condensed Matter)  
Energy-resolved He atom scattering is adopted to investigate self-diffusion on Ag͑110͒ in a temperature range well below the bulk melting point.  ...  The diffusion coefficients are estimated and strong anisotropy is evidenced by adsorbed atoms moving mainly along the ͗11 0͘ surface rows.  ...  Vladiskovic for assistance in measurements and data analysis. Mr. A. Gussoni is gratefully acknowledged for technical support.  ... 
doi:10.1103/physrevb.66.045414 fatcat:zu37bptk75e5fhkziphldkhsly

Analysis of $alpha$ + $^{40}$Ca and $alpha$ + $^{58}$Ni Elastic Scatterings at $E_{lab}$ = 240 MeV

Yong Joo KIM*
2018 New Physics Sae Mulli  
The second one is to use parameters calculated by matching the Gaussian density to the two-parameter Fermi density.  ...  The elastic scatterings for the α + 40 Ca and the α + 58 Ni systems at E lab = 240 MeV have been analyzed within the framework of the Coulomb-modified Glauber model using two kinds of Gaussian density  ...  ACKNOWLEDGEMENTS This research was supported by the 2018 scientific promotion program funded by Jeju National University.  ... 
doi:10.3938/npsm.68.1324 fatcat:i4e7m5ovnjfxxioj6eaihyrv6i

The momentum distribution of liquid3He

M. S. Bryan, T. R. Prisk, R. T. Azuah, W. G. Stirling, P. E. Sokol
2016 Europhysics letters  
We present high-resolution neutron Compton scattering measurements of liquid ^3He below its renormalized Fermi temperature.  ...  Theoretical predictions are in excellent agreement with the experimental data when instrumental resolution and final state effects are accounted for.  ...  We represented J IA (Y ) by means of a single Gaussian when fitting the scattering data.  ... 
doi:10.1209/0295-5075/115/66001 fatcat:ewi6ivfisrbmniemy4dgujlppa

X-Ray Reflectivity and Surface Roughness [chapter]

B. M. Ocko
1990 Spectroscopic and Diffraction Techniques in Interfacial Electrochemistry  
Since the advent of high brightness synchrotron radiation sources there has been a phenomenal growth in the use of x-rays as a probe of surface structure.  ...  The technique of x-ray reflectivity is particularly relevant to electrochemists since it is capable of probing the structure normal to an electrode surface in situ.  ...  SUMMARY The technique of X-ray reflectivity prov^'es detailed information about the structure along the surface normal direction.  ... 
doi:10.1007/978-94-011-3782-9_11 fatcat:4rf27khhsvhr7g2flzfiar7kie
« Previous Showing results 1 — 15 out of 88,048 results