Publications related to Rotations in 4-dimensional Euclidean space

Stronger serial dependence in the depth plane than the fronto-parallel plane between realistic objects: Evidence from virtual reality

Visual estimates of stimulus features are systematically biased toward the features of previously encountered stimuli. Such serial dependencies have often been linked to how the brain maintains perceptual continuity. However, serial dependence has mostly b ...

2023

Optimal denoising of rotationally invariant rectangular matrices

Florent Gérard Krzakala, Lenka Zdeborová, Emanuele Troiani, Vittorio Erba

In this manuscript we consider denoising of large rectangular matrices: given a noisy observation of a signal matrix, what is the best way of recovering the signal matrix itself? For Gaussian noise and rotationally-invariant signal priors, we completely ch ...

2022

Thin Liquid Film Dynamics on a Spinning Spheroid

Edouard Boujo

The present work explores the impact of rotation on the dynamics of a thin liquid layer deposited on a spheroid (bi-axial ellipsoid) rotating around its vertical axis. An evolution equation based on the lubrication approximation was derived, which takes in ...

MDPI2021

Physics-enhanced machine learning with symmetry-adapted and long-range representations

Andrea Grisafi

Theoretical and computational approaches to the study of materials and molecules have, over the last few decades, progressed at an exponential rate. Yet, the possibility of producing numerical predictions that are on par with experimental measurements is t ...

EPFL2021

Angular Color Prediction Model for Anisotropic Halftone Prints on a Metallic Substrate

Roger Hersch, Lin Yang, Petar Pjanic

Under specular reflection, non-isotropic halftones such as line halftones printed on an ink-receiving plastic layer superposed with a metallic layer change their colors upon in-plane rotation of the print. This color change is due to the orientation-depend ...

I S & T-SOC IMAGING SCIENCE TECHNOLOGY2019

The Mutual Information in Random Linear Estimation Beyond i.i.d. Matrices

Nicolas Macris, Jean François Emmanuel Barbier, Florent Gérard Krzakala

There has been definite progress recently in proving the variational single-letter formula given by the heuristic replica method for various estimation problems. In particular, the replica formula for the mutual information in the case of noisy linear esti ...

IEEE2018

A transmurally heterogeneous orthotropic activation model for ventricular contraction and its numerical validation

Alfio Quarteroni, Luca Dede', Simone Rossi, Luca Barbarotta

Models for cardiac mechanics require an activation mechanism properly representing the stress-strain relations in the contracting myocardium. In this paper, we propose a new activation model that accounts for the transmural heterogeneities observed in myoc ...

Wiley2018

Color changing effects with cross-halftone prints on metal

Roger Hersch, Petar Pjanic

We propose new methods for creating color varying prints with classical cyan, magenta, yellow inks on a metallic substrate. We use a special crossline halftone with optimized surface coverages of the inks to create color prints on a metallic surface whose ...

2017

Color changing effects with cross-halftone prints

Roger Hersch, Petar Pjanic

We propose new methods for creating color varying prints with classical cyan, magenta, yellow inks on a metallic specularly reflecting or on a white diffusely reflecting substrate. We use a special cross-line halftone with optimized surface coverages of th ...

2017

Shear Resistance and Failure Modes of Edgewise Multiple Tab-and-Slot Joint (MTSJ) Connection with Dovetail Design for Thin LVL spruce plywood Kerto-Q Panels

Yves Weinand, Stéphane Nicolas Roche, Mira Dedijer

The objective of this study is to experimentally analyse effects of geometry variations of Multiple Tab and Slot Joint (MTSJ) connection with dovetail design on shear mechanical behaviour. Direct shear test was performed on angular (phi=90°) MTSJ connectio ...

2016

A block algorithm for computing antitriangular factorizations of symmetric matrices

Daniel Kressner, Zvonimir Bujanovic

Any symmetric matrix can be reduced to antitriangular form in finitely many steps by orthogonal similarity transformations. This form reveals the inertia of the matrix and has found applications in, e.g., model predictive control and constraint preconditio ...

Springer2016

Stability of stationary wave maps from a curved background to a sphere

Sohrab Mirshams Shahshahani

We study time and space equivariant wave maps from

M \times \mathbb{R} \rightarrow S^2

, where

M

is dieomorphic to a two dimensional sphere and admits an action of

SO(2)

by isometries. We assume that metric on

M

can be written as $dr^2+f^2(r)d\theta ...

2016

Pressure dependence of the structure and electronic properties of Sr3Ir2O7

Henrik Moodysson Rønnow

We study the structural evolution of Sr3Ir2O7 as a function of pressure using x-ray diffraction. At a pressure of 54 GPa at room temperature, we observe a first-order structural phase transition, associated with a change from tetragonal to monoclinic symme ...

2016

An updated version of wannier90: A tool for obtaining maximally-localised Wannier functions

Nicola Marzari, Giovanni Pizzi

wannier90 is a program for calculating maximally-localised Wannier functions (MLWFs) from a set of Bloch energy bands that may or may not be attached to or mixed with other bands. The formalism works by minimising the total spread of the MLWFs in real spac ...

Elsevier Science Bv2014

Accurate Measurement of Concurrent Flexion-Extension and Internal-External Rotations in Smart Knee Prostheses

Kamiar Aminian, Arash Arami, Axelle Vallet

In this work, we present a magnetic measurement system for integration into smart knee prostheses to accurately measure the combination of two knee rotations; namely Flexion- Extension and Internal-External rotations. This measurement system consists of tw ...

Institute of Electrical and Electronics Engineers2013

Accurate angle estimation in smart knee prostheses via magnetic implantable and skin-mounted sensors

Kamiar Aminian, Arash Arami, Arnaud Barré

In this work we investigated how to measure concurrently flexion-extension and internal-external rotations in a smart knee prosthesis. A configuration of magnetic sensors and magnets were designed and embedded in knee prostheses in which each sensor measur ...

2013

Mechanical positioning system for surgical instruments

Hannes Bleuler, Reymond Clavel, Ricardo Daniel Rita Beira

An external manipulator for positioning surgical instruments within the abdominal cavity, comprising a hybrid kinematics with a parallel structure, able to provide four, active or passive, positional degrees of freedom to a endoscopic unit, placed in the d ...

2012

Exact geometric theory of dendronized polymer dynamics

Tudor Ratiu, François Gay-Balmaz

Dendronized polymers consist of an elastic backbone with a set of iterated branch structures (dendrimers) attached at every base point of the backbone. The conformations of such molecules depend on the elastic deformation of the backbone and the branches, ...

2012

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

An effortless procedure to align the local frame of an inertial measurement unit to the local frame of another motion capture system

Kamiar Aminian, Julien Favre, Julien Chardonnens

Inertial measurement units (IMUs) offer great opportunities to analyze segmental and joints kinematics. When combined with another motion capture system (MCS), for example, to validate new IMU-based applications or to develop mixed systems, it is necessary ...

Elsevier2012