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Publications associées (17)

Wandering principal optical axes in van der Waals triclinic materials

Nature is abundant in material platforms with anisotropic permittivities arising from symmetry reduction that feature a variety of extraordinary optical effects. Principal optical axes are essential characteristics for these effects that define light-matte ...

Nature Portfolio2024

High-order accurate entropy stable adaptive moving mesh finite difference schemes for special relativistic (magneto)hydrodynamics

Junming Duan

This paper develops high-order accurate entropy stable (ES) adaptive moving mesh finite difference schemes for the two- and three-dimensional special relativistic hydrodynamic (RHD) and magnetohydrodynamic (RMHD) equations, which is the high-order accurate ...

ACADEMIC PRESS INC ELSEVIER SCIENCE2022

Development of a semi-implicit contact methodology for finite volume stress solvers

Andreas Pautz, Carlo Fiorina, Alessandro Scolaro

The past decades have seen numerous efforts to apply the finite volume methodology to solid mechanics problems. However, only limited work has been done by the finite volume community toward the simulation of mechanical contact. In this article, we present ...

Wiley2022

Flow separation at convex banks in open channels

Koen Blanckaert

Laboratory experiments in an open channel bend provide insight into the physics of convex bank flow separation occurring in a variety of channel configurations, including confluences and bifurcations. The edge of the zone of flow separation is characterize ...

Cambridge University Press2015

Tokamak coordinate conventions: COCOS

Olivier Sauter

Dealing with electromagnetic fields, in particular current and related magnetic fields, yields "natural" physical vector relations in 3-D. However, when it comes to choosing local coordinate systems, the "usual" right-handed systems are not necessarily the ...

Elsevier Science Bv2013

Exploitation of a general-coordinate guiding centre code for the redistribution of fast ions in deformed hybrid tokamak equilibria

Jonathan Graves, Wilfred Anthony Cooper, David Pfefferlé

Self-consistent fast ion distributions are usually obtained using a code that solves the guiding-centre equations, with an appropriate fast ion source (e.g. NBI pinis) and sink (e.g. collision operators). Straight field-line coordinate systems, such as Boo ...

Iop Publishing Ltd2012

3DEX: a code for fast spherical Fourier-Bessel decomposition of 3D surveys

Anaïs Marie Rassat, Jean-Luc Starck

Context. High-precision cosmology requires the analysis of large-scale surveys in 3D spherical coordinates, i.e. spherical Fourier-Bessel decomposition. Current methods are insufficient for future data-sets from wide-field cosmology surveys. ...

2012

Vector Control of Single-Phase Voltage-Source Converters Based on Fictive-Axis Emulation

Alfred Rufer, Behrooz Bahrani, Stephan Kenzelmann

This paper presents an alternative way for the current regulation of single-phase voltage-source dc-ac converters in direct-quadrature (dq) synchronous reference frames. In a dq reference frame, ac (time varying) quantities appear as dc (time invariant) on ...

Institute of Electrical and Electronics Engineers2011

Non-axis-symmetrical punching shear around internal columns of RC slabs without transverse reinforcement

Aurelio Muttoni, Miguel Fernández Ruiz, Juan Sagaseta Albajar, Luca Tassinari

Most analytical approaches and available test data for punching shear in flat slabs assume axis-symmetrical conditions, which seems realistic for representing slabs supported on columns equally spaced in both orthogonal directions. However, in practice, th ...

Magazine of Concrete Research2011

Sparse Source Recovery from Boundary Measurements using an Extension of Prony's Method for the Poisson Equation

Djano Kandaswamy

Electroencephalography (EEG) is a key modality to monitor brain activity with high temporal resolution. EEG makes use of an array of electrodes to measure the electrical potential on the scalp. While most traditional EEG analyses have looked at EEG rhythms ...

EPFL2011

A vector controlled single-phase voltage source inverter with enhanced dynamic response

Alfred Rufer

Vector (dq) control is a powerful technique used in high dynamic performance inverters. The transformation of ac into dc quantities allows the controller to be designed as for dc-dc converters, with infinite gain at the steady-state operating point for zer ...

2010

Vector Control of Single-Phase Voltage Source Converters based on Fictive Axis Emulation

Alfred Rufer, Behrooz Bahrani, Stephan Kenzelmann

This paper presents an alternative way for controlling the current of single-phase voltage source dc-ac inverters in a dq synchronous reference frame. In a dq reference frame, ac (time varying) quantities appear as dc (time invariant) quantities allowing t ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2009

Cross-encoded magnetic resonance imaging in inhomogeneous fields

Geoffrey Bodenhausen

In magnetic resonance imaging (MRI), it is possible to cancel the effects of severe inhomogeneities of the magnetic field even if the field profile is unknown. The new ‘cross-encoded’ method is based on adiabatic frequency-modulated pulses combined with tw ...

Academic Press Inc - Elsevier Science2009

On the n-dimensional Dirichlet problem for isometric maps

Bernard Dacorogna

We exhibit explicit Lipschitz maps from R '' to R '' which have almost everywhere orthogonal gradient and are equal to zero on the boundary of a cube. We solve the problem by induction on the dimension n. (C) 2008 Elsevier Inc. All rights reserved. ...

2008

Single or triple gradients?

Geoffrey Bodenhausen, Paul Romeo Vasos, Riddhiman Sarkar, Fabien Ferrage

Pulsed Field Gradients (PFGs) have become ubiquitous tools not only for Magnetic Resonance Imaging (MRI), but also for NMR experiments designed to study translational diffusion, for spatial encoding in ultra-fast spectroscopy, for the selection of desirabl ...

Academic Press Inc - Elsevier Science2008

Some Recovery Conditions for Basis Learning by L1-Minimization

Karin Schnass, Rémi Gribonval

Many recent works have shown that if a given signal admits a sufficiently sparse representation in a given dictionary, then this representation is recovered by several standard optimization algorithms, in particular the convex

\ell^1

minimization approac ...

2008

Generic representations of orthogonal groups: the mixed functors

Christine Vespa

In previous work, we defined the category of functors F-quad, associated to F-2-vector spaces equipped with a nondegenerate quadratic form. In this paper, we define a special family of objects in the category F-quad, named the mixed functors. We give the c ...

2007