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multiple scattering Between Adjacent Sound Sources in Head-Related Transfer Function Measurement System

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Sound & Vibration 2019年第4期53卷 151-159页

作者： Guangzheng Yu Yu Liu Bosun Xie Huali Zhou Acoustic Lab. School of Physics and OptoelectronicsSouth China University of TechnologyGuangzhou510641China GAC R&D Center Guangzhou Automobile Group Co.Ltd.Guangzhou511458China.

To accelerate head-related transfer functions(HRTFs)measurement,two or more independent sound sources are usually employed in the measurement ***,the multiple scattering between adjacent sound sources may influence the accuracy of *** the other hand,the directivity of sound source could induce measurement ***,a model consisting of two spherical sound sources with approximate omni-directivity and a rigid-spherical head is proposed to evaluate the errors in HRTF measurement caused by multiple scattering between *** example of analysis using multipole re-expansion indicates that the error of ipsilateral HRTFs are within the bound of±1.0 dB below a frequency of 20 kHz,provided that the sound source radius does not exceed 0.025 m,the source distance relative to head center is not less than 0.5 m,and the angular interval between two adjacent sources is not less than 20 *** conclusions under different conditions can also be analyzed and discussed by using this calculation ***,the results are verified by measurements of HRTFs for a rigid sphere and a KEMAR artificial head.

关键词： Head-related transfer function near field measurement error multiple scattering

Numerical calculation of multiple scattering with the layer model

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Particuology 2009年第1期7卷 76-82页

作者： Yuehuan Wei Jianqi Shen Haitao Yu University of Shanghai for Science and Technology Shanghai 200093 China

The optical measurement technique based on Mie scattering has been applied to various areas, in which single scattering at low particle concentration is assumed. Nevertheless, since multiple scattering is usually unavoidable in online measurements, we present in this work a multiple scattering calculation method, in which a layer model is employed. The three-dimensional particle system is divided into a pile of layers the number of which is automatically determined, depending on the obscuration of the particle system. The calculation is found to be fast, reasonable and reliable.

关键词： multiple scattering Layer model Mie theory Forward scattering Particle analysis

Influence of single scattering and multiple scattering on backscattered Mueller matrix in turbid media

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Chinese Optics Letters 2009年第1期7卷 64-66页

作者：徐兰青李晖郑勇平 Key Laboratory of Opto-Electronic Science and Technology for Medicine(Fujian Normal University) Ministry of EducationFujian Provincial Key Lab of Photonic Technology

Monte Carlo algorithm and Stokes-Mueller formalism are used to simulate the propagation behavior of polarized light in turbid media. The influence of single scattering and multiple scattering on backscattered Mueller matrix in turbid media is discussed. Single and double scattering photons form the major part of backscattered polarization patterns, while multiple scattering photons present more likely as background. Further quantitative analyses show that single scattering approximation and double scattering approximation are quite accurate when discussing the polarization patterns near the incident point.

关键词： Light multiple scattering Photons Polarization Turbidity

Analysis of multiple scattering from two-dimensional dielectric sea surface with iterative Kirchhoff approximation

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Chinese Physics B 2010年第8期19卷 379-383页

作者：罗伟张民周平殷红成 School of Science Xidian University National Electromagnetic scattering Laboratory

An iterative method in the Kirchhoff approximation is proposed for high frequency multiple electromagnetic scattering from two-dimensional dielectric sea surface. The multiple interaction of the scattering field is characterized with the corrected electromagnetic currents of the wind-driven sea surface. The actual surface currents are approximated with the iterative solution of the corrected currents. A newly developed sea spectrum, Elfouhaily spectrum, is utilized to build the sea surface model. The shadowing correction is improved by the Dept-Buffer algorithm. The validity of the iterative Kirchhoff approximation is verified by the agreement of backscattering coefficients with the measured data.

关键词： sea surface multiple scattering iterative methods shadowing correction

UAV remote sensing atmospheric degradation image restoration based on multiple scattering APSF estimation

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Optoelectronics Letters 2017年第5期13卷 386-391页

作者：仇翔戴明尹传历 Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

Unmanned aerial vehicle(UAV) remote imaging is affected by the bad weather, and the obtained images have the disadvantages of low contrast, complex texture and blurring. In this paper, we propose a blind deconvolution model based on multiple scattering atmosphere point spread function(APSF) estimation to recovery the remote sensing image. According to Narasimhan analytical theory, a new multiple scattering restoration model is established based on the improved dichromatic model. Then using the L0 norm sparse priors of gradient and dark channel to estimate APSF blur kernel, the fast Fourier transform is used to recover the original clear image by Wiener filtering. By comparing with other state-of-the-art methods, the proposed method can correctly estimate blur kernel, effectively remove the atmospheric degradation phenomena, preserve image detail information and increase the quality evaluation indexes.

关键词： Convolution Fast Fourier transforms Image reconstruction multiple scattering Optical transfer function Restoration Signal receivers Unmanned aerial vehicles (UAV)

Holographic particle localization under multiple scattering

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Advanced Photonics 2019年第3期1卷 39-50页

作者： Waleed Tahir Ulugbek S.Kamilov Lei Tian Boston University Department of Electrical and Computer EngineeringBostonMassachusettsUnited States Washington University in St.Louis Department of Electrical and Systems EngineeringSt.LouisMissouriUnited States Washington University in St.Louis Department of Computer Science and EngineeringSt.LouisMissouriUnited States

We introduce a computational framework that incorporates multiple scattering for large-scale threedimensional(3-D)particle localization using single-shot in-line *** holographic techniques rely on single-scattering models that become inaccurate under high particle densities and large refractive index *** multiple scattering solvers become computationally prohibitive for large-scale problems,which comprise millions of voxels within the scattering *** approach overcomes the computational bottleneck by slicewise computation of multiple scattering under an efficient recursive *** the forward model,each recursion estimates the next higher-order multiple scattered field among the object *** the inverse model,each order of scattering is recursively estimated by a nonlinear optimization *** nonlinear inverse model is further supplemented by a sparsity promoting procedure that is particularly effective in localizing 3-D distributed *** show that our multiple-scattering model leads to significant improvement in the quality of 3-D localization compared to traditional methods based on single scattering *** experiments demonstrate robust inverse multiple scattering,allowing reconstruction of 100 million voxels from a single 1-megapixel hologram with a sparsity *** performance bound of our approach is quantified in simulation and validated *** work promises utilization of multiple scattering for versatile large-scale applications.

关键词： multiple scattering digital holography particle localization

multiple—scattering of Near—Edge x—ray Absorption Fine Structure of Sulphur—Passivated InP（100） Surface

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Chinese Physics Letters 2003年第7期20卷 1151-1154页

作者：曹松唐景昌沈少来陈更生马丹 DepartmentofPhysics ZhejianguniversityHangzhou310027 DepartmentofPhysics ZhejianguniversityHangzhou310027 StateKeyLaboratoryforSiliconMaterialScience ZhejianguniversityHangzhou310027

We use the multiple-scattering cluster method to calculate the sulphur 1s near-edge x-ray absorption fine structure (NEXAFS) of S-passivated InP(100) surface. The physical origins of the resonances in the NEXAFS have been unveiled. It is shown that the most important resonance is attributed to the photoelectron scattering between the central sulphur and the nearest indium atoms. The studies show that two S-S dimers with the bond lengths of 2.05 Å and 3.05 Å coexist in the surface, meanwhile the bridge and antibridge site adsorption of single S could not be ruled out. We support the scanning tunnelling microscopy result that the S-passivated InP(100) surface exhibits significant disorder.

关键词： multiple scattering

Evaluating the Effect of multiple scattering on Interception of Photosynthetically Active Radiation at Organ Scale Within Maize Canopy

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Evaluating the Effect of Multiple Scattering on Interception...

Comparison and Improvement of the Computational Efficiencies of Two FFT-Based Iterative Solution Methods for the Scalar multiple-scattering Equation

作者： Jun Meng Xinyu Guo Xiaohong Du Weiliang Wen Shenglian Lu Boxiang Xiao China National Engineering Research Center for Information Technology in Agriculture(NERCITA) Life Science Department of Luoyang Normal University

multiple scattering is a critical factor that affects the spatial distribution of photosynthetically active radiation(PAR) within the *** it is neglected sometimes to reduce the numerical complexity in plant functioning simulation with no adequate *** this study,using VisuAlea visual programming tool and Caribu module which based on the nested radiosity method,PAR interception at organ scale is analyzed on the basis of 3-dimentional architecture model of maize canopy which consists of 50 *** with photosynthesis model,the importance of multiple scattering to canopy PAR distribution is *** result shows that,the multiple scattering take notable effect on PAR intensity on leaf surface(|t|> t),especially the lower surface,and lead to a 19.88%enhancement of absorbed *** to the high light usage ratio when PAR far below the saturation point,leaves under multiple scattering conditions show an average of 7.48 μmol CO · m· sphotosynthesis rate,23.43%more than control’s 6.06 μmol CO·m·*** leaves in the lower layers of the canopy can not receive as much scattering as those in the upper layers,their resultant photosynthesis promotion almost *** a conclusion,the multiple scattering affect spatial distribution of PAR within the canopy significantly,and the multiple scattering process should be considered with special attention in crop growth simulation,especially in agronomical view.

关键词： The Nested Radiosity Model multiple scattering Spatial Distribution Canopy Photosynthetically Active Radiation

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Communications in Computational Physics 2009年第1期5卷 108-125页

作者： Kristopher T.Kim Electromagnetic scattering Branch Sensors DirectorateAir Force Research LaboratoryHanscom AFBMA 01731-3010USA

We consider two existing FFT-based fast-convolution iterative solution techniques for the scalar T-matrix multiple-scattering equation[1].The use of the FFT operation requires field values be expressed on a regular Cartesian grid and the two techniques differ in how to go about achieving *** first technique[6,7]uses the nondiagonal translation operator[1,9]of the spherical multipole field,while the second method[11]uses the diagonal translation operator of Rokhlin[10].Because of its use of the non-diagonal translator,the first technique has been thought to require a greater number of spatial convolutions than the second *** establish that the first method requires only half as many convolution operations as the second method for a comparable numerical accuracy and demonstrate,based on an actual CPU time comparison,that it can therefore perform iterations faster than the second *** then consider the respective symmetry relations of the non-diagonal and diagonal translators and discuss a memory-reduction procedure for both FFT-based *** this procedure,we need to store only the minimum sets of near-field and far-field translation operators and generate missing elements on the fly using the symmetry *** show that the relative cost of generating the missing elements becomes smaller as the number of scatterers increases.

关键词： multiple scattering iterative method FFT symmetry