Results 1  10
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172
Cemgil, “Probabilistic latent tensor factorization
 in LVA/ICA, 2010
"... Abstract. We develop a probabilistic framework for multiway analysis of high dimensional datasets. By exploiting a link between graphical models and tensor factorization models we can realize any arbitrary tensor factorization structure, and many popular models such as CP or TUCKER models with Eucli ..."
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Cited by 13 (0 self)
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problem. We derive the generic form of update equations for multiplicative and alternating least squares. We also propose a straightforward matricisation procedure to convert elementwise equations into the matrix forms to ease implementation and parallelisation.
RADICALS OF 0REGULAR ALGEBRAS
"... We consider a generalisation of the KuroshAmitsur radical theory for rings (and more generally multioperator groups) which applies to 0regular varieties in which all operations preserve 0. We obtain results for subvarieties, quasivarieties and elementwise equationally defined classes. A number o ..."
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Cited by 1 (0 self)
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We consider a generalisation of the KuroshAmitsur radical theory for rings (and more generally multioperator groups) which applies to 0regular varieties in which all operations preserve 0. We obtain results for subvarieties, quasivarieties and elementwise equationally defined classes. A number
Coil sensitivity encoding for fast MRI. In:
 Proceedings of the ISMRM 6th Annual Meeting,
, 1998
"... New theoretical and practical concepts are presented for considerably enhancing the performance of magnetic resonance imaging (MRI) by means of arrays of multiple receiver coils. Sensitivity encoding (SENSE) is based on the fact that receiver sensitivity generally has an encoding effect complementa ..."
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Cited by 193 (3 self)
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image for each array element using discrete Fourier transform (DFT). The second step then is to create a fullFOV image from the set of intermediate images. To achieve this one must undo the signal superposition underlying the foldover effect. That is, for each pixel in the reduced FOV the signal
Discontinuous HpFinite Element Methods For AdvectionDiffusion Problems
 SIAM J. Numer. Anal
, 2000
"... We consider the hpversion of the discontinuous Galerkin finite element method for secondorder partial differential equations with nonnegative characteristic form. This class of equations includes secondorder elliptic and parabolic equations, first)rder hyperbolic equations, as well as problems of ..."
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Cited by 101 (12 self)
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power of p is obtained. These estimates are then combined to deduce an error bound in the general case. For elementwise analytic solutions the method exhibits exponential rates of convergence under prefinement. The theoretical results are illustrated by numerical experiments. Key words. hp
On the Uniqueness of Nonnegative Sparse Solutions to Underdetermined Systems of Equations
, 2008
"... An underdetermined linear system of equations Ax = b with nonnegativity constraint x 0 is considered. It is shown that for matrices A with a rowspan intersecting the positive orthant, if this problem admits a sufficiently sparse solution, it is necessarily unique. The bound on the required sparsity ..."
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Cited by 44 (0 self)
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, considering a matrix A with arbitrary column norms, and an arbitrary monotone elementwise concave penalty replacing the `1norm objective function. Finally, from a numerical point of view, a greedy algorithm—a variant of the matching pursuit—is presented, such that it is guaranteed to find this sparse
A NonNegative and Sparse Enough Solution of an Underdetermined Linear System of Equations is Unique
, 2007
"... In this paper we consider an underdetermined linear system of equations Ax = b with nonnegative entries of A and b, and the solution x being also required to be nonnegative. We show that if there exists a sufficiently sparse solution to this problem, it is necessarily unique. Furthermore, we presen ..."
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Cited by 32 (2 self)
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matrix A with arbitrary column norms, and an arbitrary monotone elementwise concave penalty replacing the ℓ1norm objective function, we generalize known equivalence results. Beyond the desirable generalization that this result introduces, we show how it is exploited to lead to the above
A symmetric mixed finite element method for nearly incompressible elasticity based on biorthogonal systems. Numer. Methods for Partial Differential Equations
, 2012
"... Abstract. We consider a mixed finite element method for approximating the solution of nearly incompressible elasticity and Stokes equations. The finite element method is based on quadrilateral and hexahedral triangulation using primal and dual meshes. We use the standard bilinear and trilinear fini ..."
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Cited by 1 (0 self)
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finite element space enriched with elementwise defined bubble functions with respect to the primal mesh for the displacement or velocity, whereas the pressure space is discretised by using a piecewise constant finite element space with respect to the dual mesh.
Sparse NonNegative Solution of a Linear System of Equations is Unique
"... Abstract—We consider an underdetermined linear system of equations Ax = b with nonnegative entries of A and b, andthe solution x being also required to be nonnegative. We show that if there exists a sufficiently sparse solution to this problem, it is necessarily unique. Furthermore, we present a g ..."
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Cited by 2 (0 self)
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enough solutions. Considering a matrix A with arbitrary column norms, and an arbitrary monotone elementwise concave penalty replacing the ℓ1norm objective function, we generalize known equivalence results, and use those to derive the above uniqueness claim. I.
BEYOND PRESSURE STABILIZATION: A LOW ORDER LOCAL PROJECTION METHOD FOR THE OSEEN EQUATION
"... Abstract. This work proposes a new local projection stabilized finite element method (LPS) for the Oseen problem. The method adds to the Galerkin formulation new fluctuation terms which are parameterfree, symmetric and easily computable at the element level. Proposed for the pair P1/Pl, l = 0, 1, ..."
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, when the pressure is continuously or discontinuously approximated, wellposedeness and error optimality are proved. In addition, we introduce a cheap strategy to recover an elementwise mass conservative velocity field in the discontinuous pressure case, a property usually neglected in the stabilized
Constrained Dirichlet boundary control in L² for a class of evolution equations
"... Optimal Dirichlet boundary control based on the very weak solution of a parabolic state equation is analysed. This approach allows to consider the boundary controls in L2 which has advantages over approaches which consider control in Sobolev involving (fractional) derivatives. Pointwise constrain ..."
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Cited by 15 (3 self)
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Optimal Dirichlet boundary control based on the very weak solution of a parabolic state equation is analysed. This approach allows to consider the boundary controls in L2 which has advantages over approaches which consider control in Sobolev involving (fractional) derivatives. Pointwise
Results 1  10
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172