Results 21 to 30 of about 505,660 (243)
Novel Watermarking Methods Based on Frequency Domain and Singular Value Decomposition
Communications, 2013 Nowadays, the copyright laws protecting the digital content are getting quite common. One of the important things is to protect the original or compressed images against illegal use. Frequency domain watermarking methods are used in most cases in today's
Petr Cika, Martin Zukal
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A sparse decomposition of low rank symmetric positive semi-definite matrices [PDF]
, 2016 Suppose that $A \in \mathbb{R}^{N \times N}$ is symmetric positive semidefinite with rank $K \le N$. Our goal is to decompose $A$ into $K$ rank-one matrices $\sum_{k=1}^K g_k g_k^T$ where the modes $\{g_{k}\}_{k=1}^K$ are required to be as sparse as ...
Hou, Thomas Y. +2 more
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Adaptive Aggregation Based Domain Decomposition Multigrid for the Lattice Wilson Dirac Operator [PDF]
, 2014 In lattice QCD computations a substantial amount of work is spent in solving discretized versions of the Dirac equation. Conventional Krylov solvers show critical slowing down for large system sizes and physically interesting parameter regions.
Frommer, Andreas +4 more
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Oil & Gas Science and Technology, 2014 Multiphase, compositional porous media flow models lead to the solution of highly heterogeneous systems of Partial Differential Equations (PDE). We focus on overlapping Schwarz type methods on parallel computers and on multiscale methods.
Dolean Victorita +4 more
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A Posteriori Error Estimates for the Generalized Overlapping Domain Decomposition Methods
Journal of Applied Mathematics, 2012 A posteriori error estimates for the generalized overlapping domain decomposition method (GODDM) (i.e., with Robin boundary conditions on the interfaces), for second order boundary value problems, are derived.
Hakima Benlarbi, Ahmed-Salah Chibi
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Generating Equidistributed Meshes in 2D via Domain Decomposition
, 2013 In this paper we consider Schwarz domain decomposition applied to the generation of 2D spatial meshes by a local equidistribution principle. We briefly review the derivation of the local equidistribution principle and the appropriate choice of boundary ...
Haynes, Ronald D. +1 more
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A course space construction based on local Dirichlet-to-Neumann maps [PDF]
, 2011 Coarse-grid correction is a key ingredient of scalable domain decomposition methods. In this work we construct coarse-grid space using the low-frequency modes of the subdomain Dirichlet-to-Neumann maps and apply the obtained two-level preconditioners to ...
Dohrmann C. R. +4 more
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A User-Based Cross Domain Collaborative Filtering Algorithm Based on a Linear Decomposition Model
IEEE Access, 2017 Sparsity is a tough problem in a single domain collaborative filtering (CF) recommendation system as it is difficult to compute the similarities among users accurately. Recently, cross domain CF is a new way to alleviate this difficulty.
Xu Yu +3 more
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Time integration and the Trefftz Method Part I - First-order and parabolic problems
Computer Assisted Methods in Engineering and Science, 2023 The finite element method is applied in the time domain to establish formulations for the integration of first-order and parabolic (transient) problems. The modal decomposition concept is applied using two distinct approaches.
João A. Teixeira de Freitas
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Nihon Kikai Gakkai ronbunshu, 2015 Actual problems in science and industrial applications are modeled by multi-materials and large-scale unstructured mesh, and the finite element analysis has been widely used to solve such problems on the parallel computer.
Masao OGINO
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