Publications associées à Structure différentielle

Symplectic dynamical low rank approximation of wave equations with random parameters

Fabio Nobile, Eleonora Musharbash, Eva Vidlicková

In this paper we propose a dynamical low-rank strategy for the approximation of second order wave equations with random parameters. The governing equation is rewritten in Hamiltonian form and the approximate solution is expanded over a set of 2S dynamical ...

2020

Property FW, differentiable structures and smoothability of singular actions

Yash Lodha, Nicolas Matte Bon

We provide a smoothening criterion for group actions on manifolds by singular diffeomorphisms. We prove that if a countable group Gamma has the fixed point property FW for walls (for example, if it has property(T)), every aperiodic action of Gamma by diffe ...

WILEY2020

Hyperbolicity as an obstruction to smoothability for one-dimensional actions

Yash Lodha

Ghys and Sergiescu proved in the 1980s that Thompson's group T, and hence F, admits actions by C-infinity diffeomorphisms of the circle. They proved that the standard actions of these groups are topologically conjugate to a group of C-infinity diffeomorphi ...

GEOMETRY & TOPOLOGY PUBLICATIONS2019

Exact Smooth Term Structure Estimation

Damir Filipovic, Sander Félix M Willems

We present a non-parametric method to estimate the discount curve from market quotes based on the Moore-Penrose pseudoinverse. The discount curve reproduces the market quotes perfectly, has maximal smoothness, and is given in closed-form. The method is eas ...

2018

Exact Smooth Term-Structure Estimation

Damir Filipovic, Sander Félix M Willems

We present a nonparametric method to estimate the discount curve from market quotes based on the Moore-Penrose pseudoinverse. The discount curve reproduces the market quotes perfectly, has maximal smoothness, and is given in closed-form. The method is easy ...

SIAM PUBLICATIONS2018

Switchable silver clusters : crystals for novel electronics

Sergio Allegri

Metallic nanoclusters form a family of novel materials with atomically defined hybrid organic/inorganic structures. Among these materials, clusters containing 44 silver atoms have emerged as one of the most interesting, because of their exceptional electro ...

EPFL2016

Riemannian Optimization for Solving High-Dimensional Problems with Low-Rank Tensor Structure

Michael Maximilian Steinlechner

In this thesis, we present a Riemannian framework for the solution of high-dimensional optimization problems with an underlying low-rank tensor structure. Here, the high-dimensionality refers to the size of the search space, while the cost function is scal ...

EPFL2016

Signal structure: from manifolds to molecules and structured sparsity

Sofia Karygianni

Effective representation methods and proper signal priors are crucial in most signal processing applications. In this thesis we focus on different structured models and we design appropriate schemes that allow the discovery of low dimensional latent struct ...

EPFL2015

Design and fabrication of a novel centimeter scale three dimensional silicon tip, tilt and piston mirror mechanism

François Barrot, Dara Zaman Bayat, Johannes Richard Cornelis Geerit Kruis, Rémy Fournier

A novel centimetre scale tip tilt piston mirror mechanism has been designed in silicon. The mirror consists of three identical mechanism parts and one mirror part. The fabrication of the parts was done with photolithography and Deep Reactive Ion Etching an ...

2013

Extended Focus Optical Coherence Microscopy : Theory and Application

Martin Villiger

Optical coherence tomography (OCT) is an interferometric imaging technique that can provide depth resolved cross-sectional views of biological tissue. OCT employs light with low temporal and yet high spatial coherence. The sample is illuminated point by po ...

EPFL2010