Zobrazeno 1 - 10
of 272
pro vyhledávání: '"SIMONCINI, VALERIA"'
In this paper, we explore quadratures for the evaluation of $B^T \phi(A) B$ where $A$ is a symmetric nonnegative-definite matrix in $\mathbb{R}^{n \times n}$, $B$ is a tall matrix in $\mathbb{R}^{n \times p}$, and $\phi(\cdot)$ represents a matrix fu
Externí odkaz:
http://arxiv.org/abs/2407.21505
Autor:
Liu, Sijing, Simoncini, Valeria
We consider discontinuous Galerkin methods for an elliptic distributed optimal control problem constrained by a convection-dominated problem. We prove global optimal convergence rates using an inf-sup condition, with the diffusion parameter $\varepsi
Externí odkaz:
http://arxiv.org/abs/2406.09276
Thanks to its great potential in reducing both computational cost and memory requirements, combining sketching and Krylov subspace techniques has attracted a lot of attention in the recent literature on projection methods for linear systems, matrix f
Externí odkaz:
http://arxiv.org/abs/2311.16019
Adaptive cubic regularization methods for solving nonconvex problems need the efficient computation of the trial step, involving the minimization of a cubic model. We propose a new approach in which this model is minimized in a low dimensional subspa
Externí odkaz:
http://arxiv.org/abs/2306.14290
Among randomized numerical linear algebra strategies, so-called sketching procedures are emerging as effective reduction means to accelerate the computation of Krylov subspace methods for, e.g., the solution of linear systems, eigenvalue computations
Externí odkaz:
http://arxiv.org/abs/2306.06481
Given the matrix equation ${\bf A X} + {\bf X B} + f({\bf X }) {\bf C} ={\bf D}$ in the unknown $n\times m$ matrix ${\bf X }$, we analyze existence and uniqueness conditions, together with computational solution strategies for $f \,: \mathbb{R}^{n \t
Externí odkaz:
http://arxiv.org/abs/2209.00897
We introduce a very weak space-time variational formulation for the wave equation, prove its well-posedness (even in the case of minimal regularity) and optimal inf-sup stability. Then, we introduce a tensor product-style space-time Petrov-Galerkin d
Externí odkaz:
http://arxiv.org/abs/2107.12119
Dictionary Learning (DL) is one of the leading sparsity promoting techniques in the context of image classification, where the "dictionary" matrix D of images and the sparse matrix X are determined so as to represent a redundant image dataset. The re
Externí odkaz:
http://arxiv.org/abs/2107.11644
The synthesis of suboptimal feedback laws for controlling nonlinear dynamics arising from semi-discretized PDEs is studied. An approach based on the State-dependent Riccati Equation (SDRE) is presented for H2 and Hinf control problems. Depending on t
Externí odkaz:
http://arxiv.org/abs/2106.07163
Rational Krylov subspaces have become a reference tool in dimension reduction procedures for several application problems. When data matrices are symmetric, a short-term recurrence can be used to generate an associated orthonormal basis. In the past
Externí odkaz:
http://arxiv.org/abs/2103.04054