Publications associées à Valeur absolue

The Halos and Environments of Nearby Galaxies (HERON) survey IV. Complexity in the boxy galaxies NGC720 and NGC2768

The shapes of galaxies, their outer regions in particular, are important guideposts to their formation and evolution. In this work, we report on the discovery of strongly box-shaped morphologies of the otherwise well-studied elliptical and lenticular galax ...

Edp Sciences S A2024

Preserving the positivity of the deformation gradient determinant in intergrid interpolation by combining RBFs and SVD: Application to cardiac electromechanics

Alfio Quarteroni, Francesco Regazzoni

The accurate, robust and efficient transfer of the deformation gradient tensor between meshes of different resolution is crucial in cardiac electromechanics simulations. This paper presents a novel method that combines rescaled localized Radial Basis Funct ...

Elsevier Science Sa2023

Dipole polarizability of time-varying particles

Romain Christophe Rémy Fleury, Theodoros Koutserimpas, Mohammad Sajjad Mirmoosa

Invariance under time translation (or stationarity) is probably one of the most important assumptions made when investigating electromagnetic phenomena. Breaking this assumption is expected to open up novel possibilities and result in exceeding conventiona ...

2022

Nonlinear Inverse Problems in Quantitative Phase Imaging

Thanh-An Michel Pham

The topic of this thesis is the development of new algorithmic reconstruction methods for quantitative phase imaging (QPI). In the past decade, advanced QPI has emerged as a valuable tool to study label-free biological samples and uncover their 3D structur ...

EPFL2022

Proximity Results and Faster Algorithms for Integer Programming Using the Steinitz Lemma

Friedrich Eisenbrand

We consider integer programming problems in standard form max{c(T)x : Ax = b, x >= 0, x is an element of Z(n)} where A is an element of Z(mxn), b is an element of Z(m), and c is an element of Z(n). We show that such an integer program can be solved in time ...

ASSOC COMPUTING MACHINERY2020

From Polarizability to Effective Permittivity of Time-Varying Materials

Romain Christophe Rémy Fleury, Theodoros Koutserimpas, Mohammad Sajjad Mirmoosa

In this talk, we describe excitation of time-varying dipolar particles (time-modulated meta-atoms) by external time-varying fields from a nonstationary and causal perspective. For a time-harmonic excitation, we introduce a complex-valued function, called t ...

IEEE2020

The Pristine Dwarf-Galaxy survey - II. In-depth observational study of the faint Milky Way satellite Sagittarius II

Pascale Jablonka, Nicolas Lawrence Etienne Longeard

We present an extensive study of the Sagittarius II (Sgr II) stellar system using MegaCam g and i photometry, narrow-band, metallicity-sensitive calcium H&K doublet photometry and Keck II/DEIMOS multiobject spectroscopy. We derive and refine the Sgr II str ...

OXFORD UNIV PRESS2020

Thermorefractive noise in silicon-nitride microresonators

Tobias Kippenberg, Junqiu Liu, Erwan Guillaume Albert Lucas, Arslan Sajid Raja, Nils Johan Engelsen, Guanhao Huang

Thermodynamic noise places a fundamental limit on the frequency stability of dielectric optical resonators. Here, we present the characterization of thermorefractive noise in photonic-chip-based silicon-nitride (Si3N4) microresonators and show that thermor ...

AMER PHYSICAL SOC2019

Generalized Norm-compatible Systems on Unitary Shimura Varieties

Mohamed Réda Boumasmoud

We define and study in terms of integral Iwahoriâ Hecke algebras a new class of geometric operators acting on the Bruhat-Tits building of connected reductive groups over p-adic fields. These operators, which we call U-operators, generalize the geometric n ...

EPFL2019

Robustness of Yu-Shiba-Rusinov resonances in the presence of a complex superconducting order parameter

Klaus Kern, Markus Etzkorn, Jacob Senkpiel

Robust quantum systems rely on having a protective environment with minimized relaxation channels. Super-conducting gaps play an important role in the design of such environments. The interaction of localized single spins with a conventional superconductor ...

AMER PHYSICAL SOC2019

Proximity results and faster algorithms for Integer Programming using the Steinitz Lemma

Friedrich Eisenbrand

We consider integer programming problems in standard form max{c(T)x : Ax = b; x >= 0, x is an element of Z(n)} where A is an element of Z(mxn), b is an element of Z(m) and c is an element of Z(n). We show that such an integer program can be solved in time ...

ASSOC COMPUTING MACHINERY2018

Four-Variable Expanders Over The Prime Fields

Adrian Claudiu Valculescu, Van Thang Pham, Seyed Hossein Nassajianmojarrad

Let F-p be a prime field of order p > 2, and let A be a set in F-p with very small size in terms of p. In this note, we show that the number of distinct cubic distances determined by points in A x A satisfies vertical bar(A - A)(3) + (A - A)(3 vertical bar ...

AMER MATHEMATICAL SOC2018

Testing parallaxes with local Cepheids and RR Lyrae stars

Stephan Morgenthaler, Mikaël Martino, Shuangqing Liao

Context. Parallaxes for 331 classical Cepheids, 31 Type II Cepheids, and 364 RR Lyrae stars in common between Gaia and the HIPPARCOS and Tycho-2 catalogues are published in Gaia Data Release 1 (DR1) as part of the Tycho-Gaia Astrometric Solution (TGAS). Ai ...

Edp Sciences S A2017

ARE ULTRA-FAINT GALAXIES AT z=6-8 RESPONSIBLE FOR COSMIC REIONIZATION? COMBINED CONSTRAINTS FROM THE HUBBLE FRONTIER FIELDS CLUSTERS AND PARALLELS

Jean-Paul Richard Kneib, Hakim Atek, Benjamin Yvan Alexandre Clement, Mathilde Jauzac, Johan Richard

We use deep Hubble Space Telescope imaging of the Frontier Fields to accurately measure the galaxy rest-frame ultraviolet luminosity function (UV LF) in the redshift range z similar to 6-8. We combine observations in three lensing clusters, A2744, MACS 041 ...

Iop Publishing Ltd2015

New constraints on the faint end of the UV luminosity function at z∼ 7-8 using the gravitational lensing of the hubble frontier fields cluster A2744

Jean-Paul Richard Kneib, Hakim Atek, Benjamin Yvan Alexandre Clement, Mathilde Jauzac, Johan Richard

Exploiting the power of gravitational lensing, the Hubble Frontier Fields (HFF) program aims at observing six massive galaxy clusters to explore the distant universe far beyond the limits of blank field surveys. Using the complete Hubble Space Telescope ob ...

American Astronomical Society2015

Liftings of reduction maps for quaternion algebras

Dimitar Petkov Jetchev

We construct liftings of reduction maps from complex multiplication (CM) points to supersingular points for general quaternion algebras and use these liftings to establish a precise correspondence between CM points on indefinite quaternion algebras with a ...

Oxford University Press2013

A Comparison Between Joint Coordinate System and Attitude Vector for Multi-segment foot Kinematics

Kamiar Aminian, Julien Favre, Hossein Rouhani, Xavier Crevoisier

The joint angles of multi-segment foot models have been primarily described using two mathematical methods: the joint coordinate system and the attitude vector. This study aimed to determine whether the angles obtained through these two descriptors are com ...

Elsevier2012

Discrete choice models with multiplicative error terms

Michel Bierlaire

The conditional indirect utility of many random utility maximization (RUM) discrete choice models is specified as a sum of an index V depending on observables and an independent random term. In general, the universe of RUM consistent models is much larger, ...

2009

Shift-Invariant Spaces from Rotation-Covariant Functions

Michaël Unser, Dimitri Nestor Alice Van De Ville, Thierry Blu

We consider shift-invariant multiresolution spaces generated by rotation-covariant functions ρ in

\mathbb{R}^{ 2 }

. To construct corresponding scaling and wavelet functions, ρ has to be localized with an appropriate multiplier, such that the localized ...

Elsevier2008

Influence of residual disorder on the anticrossing of Bloch modes probed in k space

Romuald Houdré, Nicolas Le Thomas, Vasily Zabelin

We retrieve the dispersion properties of photonic crystal waveguides near the band edge with high experimental accuracy. The dispersion diagram of the waveguide modes in the complex-valued plane is directly measured in the far ﬁeld by using a Fourier space ...

2008