Zobrazeno 1 - 10
of 846
pro vyhledávání: '"A Brehier"'
We consider a class of stochastic gradient optimization schemes. Assuming that the objective function is strongly convex, we prove weak error estimates which are uniform in time for the error between the solution of the numerical scheme, and the solu
Externí odkaz:
http://arxiv.org/abs/2411.05538
Dust grains play a significant role in several astrophysical processes, including gas/dust dynamics, chemical reactions, and radiative transfer. Replenishment of small-grain populations is mainly governed by fragmentation during pair-wise collisions
Externí odkaz:
http://arxiv.org/abs/2404.11851
Autor:
Beck, Geoffrey, Bréhier, Charles-Edouard, Chevillard, Laurent, Grande, Ricardo, Ruffenach, Wandrille
Publikováno v:
Phys. Rev. Research 6, 033048 (2024)
Motivated by the modeling of the spatial structure of the velocity field of three-dimensional turbulent flows, and the phenomenology of cascade phenomena, a linear dynamics has been recently proposed able to generate high velocity gradients from a sm
Externí odkaz:
http://arxiv.org/abs/2403.05401
Autor:
Bréhier, Charles-Edouard, Cohen, David
We consider a class of linear Vlasov partial differential equations driven by Wiener noise. Different types of stochastic perturbations are treated: additive noise, multiplicative It\^o and Stratonovich noise, and transport noise. We propose to emplo
Externí odkaz:
http://arxiv.org/abs/2402.18982
The detection of multiple targets in an enclosed scene, from its outside, is a challenging topic of research addressed by Through-the-Wall Radar Imaging (TWRI). Traditionally, TWRI methods operate in two steps: first the removal of wall clutter then
Externí odkaz:
http://arxiv.org/abs/2307.12592
We study a class of stochastic semilinear damped wave equations driven by additive Wiener noise. Owing to the damping term, under appropriate conditions on the nonlinearity, the solution admits a unique invariant distribution. We apply semi-discrete
Externí odkaz:
http://arxiv.org/abs/2306.13998
We introduce a positivity-preserving numerical scheme for a class of nonlinear stochastic heat equations driven by a purely time-dependent Brownian motion. The construction is inspired by a recent preprint by the authors where one-dimensional equatio
Externí odkaz:
http://arxiv.org/abs/2304.11064
We construct a positivity-preserving Lie--Trotter splitting scheme with finite difference discretization in space for approximating the solutions to a class of nonlinear stochastic heat equations with multiplicative space-time white noise. We prove t
Externí odkaz:
http://arxiv.org/abs/2302.08858
Publikováno v:
Journal of fluid mechanics, vol. 948, A42 (2022)
In this article, we study numerically the dispersion of colloids in a two-dimensional cellular flow in the presence of an imposed mean salt gradient. Owing to the additional scalar, the colloids do not follow exactly the Eulerian flow field, but have
Externí odkaz:
http://arxiv.org/abs/2209.10667
Autor:
Bréhier, Charles-Edouard
We study a family of numerical schemes applied to a class of multiscale systems of stochastic differential equations. When the time scale separation parameter vanishes, a well-known homogenization or Wong--Zakai diffusion approximation result states
Externí odkaz:
http://arxiv.org/abs/2208.00448