Publications associées à Sparse non-negative super-resolution - simplified and stabilised

An Efficient Sampling Algorithm for Non-smooth Composite Potentials

We consider the problem of sampling from a density of the form p(x) ? exp(-f (x) - g(x)), where f : Rd-+ R is a smooth function and g : R-d-+ R is a convex and Lipschitz function. We propose a new algorithm based on the Metropolis-Hastings framework. Under ...

Microtome Publishing2022

Coarse graining and large-N behavior of the d-dimensional N-clock model

Matthias Ruf, Matthias Benjamin Ruf

We study the asymptotic behavior of the N-clock model, a nearest neighbors ferromagnetic spin model on the d-dimensional cubic epsilon-lattice in which the spin field is constrained to take values in a discretization S-N of the unit circle S-1 consisting o ...

2021

Functional registration and local variations: Identifiability, rank, and tuning

Victor Panaretos, Anirvan Chakraborty

We develop theory and methodology for the problem of nonparametric registration of functional data that have been subjected to random deformation (warping) of their time scale. The separation of this phase variation ("horizontal" variation) from the amplit ...

2021

A reflected forward-backward splitting method for monotone inclusions involving Lipschitzian operators

Volkan Cevher, Cong Bang Vu

In this paper, we propose a novel splitting method for finding a zero point of the sum of two monotone operators where one of them is Lipschizian. The weak convergence the method is proved in real Hilbert spaces. Applying the proposed method to composite m ...

2021

Transient fission matrix approach for assessing complex kinetics behavior in the ZEPHYR ZPR coupled core configurations

Axel Guy Marie Laureau

CEA is currently working on a new ZPR called ZEPHYR (Zero power Experimental PHYsics Reactor), to be built on the Cadarache Center in the next decade. Its awaited experimental capacities should go well beyond traditional needs, and in particular extended p ...

PERGAMON-ELSEVIER SCIENCE LTD2019

Non-local Functionals Related to the Total Variation and Connections with Image Processing

Hoài-Minh Nguyên

We present new results concerning the approximation of the total variation,

\int_{\Omega} |\nabla u|

, of a function

u

by non-local, non-convex functionals of the form $$ \Lambda_\delta u = \int_{\Omega} \int_{\Omega} \frac{\delta \varphi \big( |u(x) - ...

2018

Performing mathematical operations using high-index acoustic metamaterials

Romain Christophe Rémy Fleury, Farzad Zangeneh Nejad

The recent breakthrough in metamaterial-based optical computing devices (2014 Science 343 160) has inspired a quest for similar systems in acoustics, performing mathematical operations on sound waves. So far, acoustic analog computing has been demonstrated ...

2018

Wavevector-Selective Nonlinear Plasmonic Metasurfaces

Olivier Martin, Kuang-Yu Yang, Jérémy Butet, Chen Yan

Electromagnetic metasurfaces with strong non- linear responses and angular selectivity could o ff er many new avenues for designing ultrathin optics components. We investigated the optical second harmonic generation from plasmonic metasurfaces composed of ...

American Chemical Society (ACS)2017

Splines Are Universal Solutions of Linear Inverse Problems with Generalized TV Regularization

Michaël Unser, Julien René Pierre Fageot, John Paul Ward

Splines come in a variety of flavors that can be characterized in terms of some differential operator L. The simplest piecewise-constant model corresponds to the derivative operator. Likewise, one can extend the traditional notion of total variation by con ...

2017

Non-convex, non-local functionals converging to the total variation

Hoài-Minh Nguyên

We present new results concerning the approximation of the total variation, integral(Omega)vertical bar del u vertical bar, of a function u by non-local, non-convex functionals of the form Lambda delta(u) = integral(Omega)integral(Omega)delta phi(vertical ...

Elsevier2017