On-surface radiation condition for multiple scattering of waves
Aug 27, 2014 ... an inexpensive pre-conditioner for Krylov iterative solutions of BIE. ... arXiv: 1312.6750v2 [physics.comp-ph] 26 Aug 2014 ... The second category is based on boundary integral equations (BIE) leading to surface dis- ... tice is to ignore the multiple-component nature of the scatterer and enclose all obstacles ...
[ 1312.6750.pdf; - Read/Download File
arXiv:1608.00500v1 [math.NA] 1 Aug 2016 - arXiv.org
Aug 2, 2016 ... one is interested in real valued eigenvalues because the physics of the problems ... The SSM is a non-iterative algorithm which determines ... the results in the following discussions hold for multiple scatterer cases as well. ......  K. Niino and N. Nishimura, Preconditioning based on Calderon's formu-.
[ 1608.00500 - Read/Download File
Physics-based Preconditioners and Optimization
Department of Applied Physics & Applied Mathematics. Columbia University ... Krylov iteration is expensive in memory and in function ... physics-based preconditioning .... multiple scales problems in geophysical modeling .... must devise new “all-at-once” algorithms that seek “exact” feasibility only .... scatter of ghost values.
[ DD15-tutorial-friPM.pdf - Read/Download File
Acoustic multiple scattering using recursive algorithms - RCI
Jul 21, 2015 ... F.A. Amirkulova, A.N. Norris / Journal of Computational Physics 299 (2015) 787– 803 ... X is the interaction matrix that defines the coupling between each scatterer of the .... method based on Fourier series using an iterative solver (GMRES) ... Two preconditioners were proposed to increase the convergence.
[ 2015_JCP_multiple_scattering.pdf - Read/Download File
chapter 4 - IECL
Computational Methods for Multiple Scattering at High Frequency ... mentary set of the scatterer Ω− in Rd, is denoted by. Ω ... Progress in Computational Physics ( PiCP), 2010, 73-107 .... integral equation based strategies. .... introduction of nontrivial fast iterative algorithms ..... to build a geometrically-based preconditioner.
[ 10_PiCP.pdf - Read/Download File
Multi-hybrid method for investigation of EM scattering from - Springer
Science China Physics, Mechanics and Astronomy ... An iterative strategy combining Kirchhoff approximation^(KA) with the hybrid finite ... Du Y, Liu B. A numerical method for electromagnetic scattering from dielectric rough surface based on the .... twofold iterative algorithm of FE-BI-MLFMA using multilevel inverse-based ...
[ mxqu86q8r0418577.pdf - Read/Download File
Computation of scattering from clusters of spheres using the fast
A T-matrix based method of solution of the multiple scattering problem ... multilevel fast multipole method that employs fast translation algorithms. ... vergence of the iterative techniques, selection of the truncation number, errors in the ... simplicity of description, clear relation to the physics, and operation with the quantities.
[ cs-tr-4609.pdf - Read/Download File
Computation of scattering from clusters of spheres using the fast
A T-matrix based method of solution of the multiple scattering problem was ... products, a novel FMM-based preconditioner, and fast translation techniques that enable us to ... iterative techniques, selection of the truncation number, errors in the solution, and ... to be spherical, and the boundary conditions on the scatterer.
[ Gumerov_Duraiswami_jasa_04_05.pdf - Read/Download File
Sparse approximate inverse preconditioning for dense linear
a Parallel Computing Group, Physics and Mathematics Department, Aerospatiale , ... Keywords: dense linear systems, preconditioning, sparse approximate ... for complex symmetric systems with multiple right-hand sides is block QMR (see, ... of the iterative method, and on properties of the coefficient matrix (the side of the.
[ fulltext.pdf - Read/Download File
PETSc Tutorial - Mathematics and Computer Science
Jun 30, 2016 ... keep solvers decoupled from physics and discretization ... Algorithm Developers ( iterative methods and preconditioning) .... Involve MPI operations (scatter, gather, reduce, etc.) ..... Matrix-based: Jacobi, Gauss-Seidel, SOR, ILU(k), LU .... Geometric: define problem on multiple levels, use grid to compute ...
[ tutorial1.pdf - Read/Download File
Wide Frequency Band Numerical Approaches for Multiple Scattering
Feb 26, 2013 ... The representation of the solution is based on an integral equation ... Keywords: Multiple scattering; circular cylinders; wide frequency band; fast and accurate algorithms; preconditioning ... global scatterer Ω− is defined as the union of the M obstacles: Ω− = ∪M ...... otherwise, the iterative method diverges.
[ document - Read/Download File
An efficient and highly accurate solver for multi-body acoustic
The BIE is discretized using the Nyström method based on a high-order ... BIE is solved using the iterative solver GMRES , combined with a block-diagonal ... ers, let n denote the total number of discretization nodes on a single scatterer and let I ..... A block-diagonal pre-conditioner for the multibody scattering problem.
[ 2014_multibody_axisym.pdf - Read/Download File
Domain Decomposition in the Mainstream of Computational Science
schemes and physics-informed preconditioning, so that multiple scale problems are ... Algorithms for these PDE-based simulations must be highly .... Combining a Schwarz preconditioner with a Krylov iteration method inside an in- ... represent gather and scatter communication operations, mapping between a global.
[ dd14_keyes.pdf - Read/Download File
A Fast Parallel Poisson Solver on Irregular Domains Applied to
Jul 28, 2009 ... gebraic multigrid (AMG) preconditioning. We investigate ... also compare our SAAMG-PCG solver with an FFT-based solver that is ... 1. arXiv:0907.4863v1 [ physics.comp-ph] 28 Jul 2009 ... , a solver based on geometric multi- .... iteration step the CG algorithm minimizes the quadratic functional ϕ along a.
[ arXiv:0907.4863.pdf?version=1 - Read/Download File
Report - Stanford University
Jun 3, 2011 ... physics problem and an inverse model that makes changes based on ... More specific methods include the distorted Born iterative algorithm ... The set of measurements, ûj ∈ CΩr , exist at multiple frequencies and ... gives small error if the magnitude of the scatterer, p is small and the ratio between the.
[ strauss.pdf - Read/Download File
Engineering, Purdue - Purdue University
Jul 1, 2008 ... inverse problem because (1) FEM-based forward models, which ... into iterative algorithms for the inverse problem: (1) a direct ... given bioluminescent source distribution using known optical scatter and absorption properties .... performed for multiple sources, as noted in Schweiger and Arridge (1997).
[ pmb1.pdf - Read/Download File
BOUT++: Recent and current developments
Jun 2, 2014 ... Algorithms have been implemented in BOUT++ to solve a range of linear algebraic problems encountered ... extended in multiple ways by a large group of users. .... been used as part of a physics-based precondition- .... Preconditioning of iterative solver .... uses gather and scatter operations which reduces.
[ 25030896.pdf - Read/Download File
Internet2-based 3D PET image reconstruction using a PC cluster
PHYSICS IN MEDICINE AND BIOLOGY ... algorithms (e.g. Defrise et al 1997) and then using iterative 2D reconstruction rather than ... The difference between the cluster system and a multiple CPU ... scatter is estimated using a model- based approach for the ECAT HR+ ... is the diagonal EM-based preconditioning matrix.
[ ShattuckEtAl_20021.pdf - Read/Download File
Physically Based Preconditioning Techniques Applied to the First
May 1, 2014 ... Physically based preconditioning is applied to linear systems resulting from solving ... modeling fusion reactions, or web search algorithms.
[ viewcontent.cgi?article=3190&context=etd - Read/Download File
A Discrete BCG-FFT Algorithm for Solving 3D Inhomogeneous
input and multi-output linear system with known kernels. ... N logN operations per iteration, where N is the number of 3D unknowns. ... Today, commonly applied algorithms for this purpose are based on conjugate .... The scatterer is described by the distribution function O(r) de ned ...... tem," Journal of Applied Physics, vol.
[ download?doi=10.1.1.51.4121&rep=rep1&type=pdf - Read/Download File