Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Concept

Précession des équinoxes

Publications associées (25)

Delineating Conformation Control in the Photophysical Behaviour of a Molecular Donor-Acceptor-Donor Triad

Shubhajit Das

Mechanochromic luminescent materials, exhibiting a change in luminescence behavior under external stimuli have emerged as one of the promising candidates for upcoming efficient OLEDs. Recently mechanochromic luminescence was reported in a donor-acceptor-do ...

WILEY-V C H VERLAG GMBH2021

Adaptive Regularization For Three-Dimensional Optical Diffraction Tomography

Michaël Unser, Demetri Psaltis, Emmanuel Emilien Louis Soubies, Thanh-An Michel Pham, Ahmed Bassam Sayed Ayoub Mohamed Emam

Optical diffraction tomography (ODT) allows one to quantitatively measure the distribution of the refractive index of the sample. It relies on the resolution of an inverse scattering problem. Due to the limited range of views as well as optical aberrations ...

IEEE2020

Design of a Flexure Based Low Frequency Foucault Pendulum

Simon Nessim Henein, Ilan Vardi, Patrick Robert Flückiger

The Foucault pendulum is a well-known mechanism used to demonstrate the rotation of the Earth. It consists in a pendulum launched on linear orbits and, following Mach’s Principle, this line of oscillation will remain fixed with respect to absolute space bu ...

2020

Effect of damping models on the simulation of seismic axial forces in a reinforced concrete bridge pier

Katrin Beyer, João Saraiva Esteves Pacheco de Almeida

Post-reconnaissance findings after recent earthquakes have shown that the effect of the vertical acceleration component of the ground motion can be more damaging than typically considered thus far, particularly in near-field regions where the ratio of vert ...

2018

A wrist sensor and algorithm to determine instantaneous walking cadence and speed in daily life walking

Kamiar Aminian, Pierre-André Farine, Benedikt Fasel, Cyntia Duc, Farzin Dadashi, Martin Savary, Flavien Bardyn

In daily life, a person’s gait—an important marker for his/her health status—is usually assessed using inertial sensors fixed to lower limbs or trunk. Such sensor locations are not well suited for continuous and long duration measurements. A better locatio ...

Springer Heidelberg2017

Elemento de Viga Baseado em Formulação de Rigidez Enriquecido com Funções de Forma Adaptativas para Garantir Equilíbrio Axial

Katrin Beyer, João Saraiva Esteves Pacheco de Almeida, Danilo Tarquini

In the framework of Performance Based Earthquake Engineering (PBEE), assessing the inelastic behaviour of structures both at the global (force-displacement) and local (stress-strain) level is of priority importance. This goal is typically achieved by advan ...

2016

Skyrmion dynamics under uniaxial anisotropy

Dirk Grundler

Broadband microwave spectroscopy has been performed on single-crystalline GaV4S8, which exhibits a complex magnetic phase diagram including cycloidal and Neel-type skyrmion lattice phases below 13 K. At small magnetic fields two collective modes with large ...

Amer Physical Soc2016

Gaia Data Release 1 Summary of the astrometric, photometric, and survey properties

Stephan Morgenthaler, Shuangqing Liao

Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7. Aims. A summary of Gaia DR1 is presented along with illu ...

EDP Sciences2016

Space and time reconstruction of the precessing vortex core in Francis turbine draft tube by 2D-PIV

François Avellan, Arthur Tristan Favrel, Christian Landry, Andres Müller, Keita Yamamoto

Francis turbines operating at part load conditions experience the development of a high swirling flow at the runner outlet, giving rise to the development of a cavitation precessing vortex rope in the draft tube. The latter acts as an excitation source for ...

International Association For Hydraulic Research2016

Miniature silicon Michelson interferometer characterization for dimensional metrology

Dimensional metrology applications require performing measurements of profile and form/shape of parts at a nanometer-level of accuracy. Therefore, the metrological characteristics of a miniature optical micro-probe based on a Michelson interferometer are e ...

Elsevier Science Sa2015

Hydro-acoustic resonance behavior in presence of a precessing vortex rope: observation of a lock-in phenomenon at part load Francis turbine operation

François Avellan, Arthur Tristan Favrel, Christian Landry, Andres Müller, Keita Yamamoto

Francis turbines operating at part load condition experience the development of a cavitating helical vortex rope in the draft tube cone at the runner outlet. The precession movement of this vortex rope induces local convective pressure fluctuations and a s ...

IOP Publishing2014

Hydro-acoustic resonance behavior in presence of a precessing vortex rope: observation of a lock-in phenomenon at part load Francis turbine operation

François Avellan, Arthur Tristan Favrel, Andres Müller, Christian Landry, Keita Yamamoto

IOP science2014

Twist and Stretch of Helices Explained via the Kirchhoff-Love Rod Model of Elastic Filaments

John Maddocks

In various single-molecule experiments, a chiral polymer, such as DNA, is simultaneously pulled and twisted. We address an elementary but fundamental question raised by various authors: does the molecule overwind or unwind under tension? We show that withi ...

Amer Physical Soc2013

Singularity Free Parametrization of Human Limbs

Ronan Boulic, Eray Molla

In this paper we propose the Middle-Axis-Rotation (MAR) parametrization of human limbs that addresses the ill-conditioned cases of analytical Inverse Kinematics (IK) algorithms. The MAR parametrization is singularity-free in the reach space of the human li ...

ACM Press2013

Haptic interface for simulator, such as a colonoscopy simulator

Evren Samur, Lionel Flaction

The device (1 ) comprises an endoscopic interface (2) with a guiding tube (4) for guiding an endoscope, said tube (4) being mounted on bearings (5) for free rotation and comprising windows for allowing a contact between said endoscope and friction rollers ...

2011

Hydrodynamics of High Specific Power Pumps for Off-Design Operating Conditions

Part load operation of high energy centrifugal pumps is associated with increased vibration levels which may adversely affect the machines operational safety. The main sources of vibrations in centrifugal pumps are of hydrodynamic nature. The interaction b ...

EPFL2010

On the upper part load vortex rope in Francis turbine: Experimental investigation

François Avellan, Christophe Nicolet, Pierre Maruzewski, Amirreza Zobeiri

The swirling flow developing in Francis turbine draft tube under part load operation leads to pressure fluctuations usually in the range of 0.2 to 0.4 times the runner rotational frequency resulting from the so-called vortex breakdown. For low cavitation n ...

International Association For Hydraulic Research2010

Three-dimensional force measurements in optical tweezers formed with high-NA micromirrors

René Salathé, László Forró, Sylvia Jeney, Fabrice Merenda

The three-dimensional trap stiffness of optical tweezers formed with high-NA micromirrors is investigated by back-focal-plane interferometry and power spectrum analysis. Normalized stiffness values of kappa(xy)/P-trap =1.2(mu N/m)/mW and kappa(z)/P-trap = ...

Optical Society of America2009

New slip synthesis and theoretical approach of CVT slip control

Today's vehicle must be efficient in terms of gas (CO2, NOx) emissions and fuel consumption. Due to improvements in material and oil, the continuous variable transmission (CVT) is now making a breakthrough in the automotive market. The CVT decouples the en ...

EPFL2009

New designs for submillimetric press-fitting

Jacques Jacot, Fabien Bourgeois, Ludovic Charvier

Press-fitting is a very common assembly process used in many fields, especially in the watchmaking industry. It consists of introducing a shaft in a hole (also called receptor) with a certain value of tightening (or interference). However, this process is ...

Springer, 233 Spring Street, New York, Ny 10013, United States2008