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

Concept

Métrologie

Publications associées (23)

On double-descent in uncertainty quantification in overparametrized models

Lenka Zdeborová, Florent Gérard Krzakala, Bruno Loureiro, Lucas Andry Clarte

Uncertainty quantification is a central challenge in reliable and trustworthy machine learning. Naive measures such as last-layer scores are well-known to yield overconfident estimates in the context of overparametrized neural networks. Several methods, ra ...

PMLR Proceedings of Machine Learning Research2023

Calibration Transfer Methodology for Cloud Radars Based on Ice Cloud Observations

Alexis Berne, Anne-Claire Marie Billault--Roux

This article presents a calibration transfer methodology that can be used between radars of the same or dif-ferent frequency bands. This method enables the absolute calibration of a cloud radar by transferring it from another collocated instrument with kno ...

AMER METEOROLOGICAL SOC2023

Optical measurement method for mechanical time base characterization

Simon Nessim Henein, Etienne Frédéric Gabriel Thalmann

The recent adoption of silicon components by the mechanical watch industry has triggered the search for new time bases to advantageously replace the traditional balance and hairspring oscillator. In particular, flexure-based oscillators manufactured in sil ...

euspen2021

Precision Positioning of Microrobots for Multi-Object Spectrographs

Luzius Gregor Kronig

How does one study the evolution of the Milky Way, or the expansion of the Universe, or explore the mysteries of Dark energy? To investigate these complex topics, astronomers require data, and a great deal of it, in the form of the spectra of stars, galaxi ...

EPFL2020

Measurement data interpretation and prediction for optimal management of bridges

Marco Proverbio

For many developed countries, the asset management of aging infrastructure continues to present challenges and risks. Around the world, built-environment assets such as bridges, require functional changes and future-proofing in order to accommodate new and ...

EPFL2019

Teaching Measurement Fundamentals

Guglielmo Frigo

While it has always been true that measurements are made to guide decision-making, there is abundant evidence that not all measurement results are meaningful. We give examples of fully-functional, tested and trusted measurement systems producing nonsensica ...

IEEE2018

High density fiber postitioner system for massive spectroscopic surveys

Jean-Paul Richard Kneib, Hannes Bleuler, Mohamed Bouri, Luzius Gregor Kronig, Philipp Hörler

We describe here a novel design of a fast high-density robotized fiber positioner system for massive spectroscopic surveys. The fiber positioners are compact, robust, and they can be coordinated, allowing for a high spatial density. Furthermore, the high a ...

OXFORD UNIV PRESS2018

Guidance, Navigation and Control for Autonomous Cooperative Docking of CubeSats

Volker Gass, Camille Sébastien Pirat

Is it possible to dock CubeSats in Low Earth Orbit? The challenges are mainly associated with the level of miniaturisation. A docking mechanism was designed, built and tested in the laboratory. Results show that a relative precision better than 1 cm and 2 ...

2018

Design and performances of an optical metrology system to test position and tilt accuracy of fiber positioners

Jean-Paul Richard Kneib, Mohamed Bouri, Luzius Gregor Kronig, Philipp Hörler

This paper describes the design of an optical metrology system for fiber positioners. The system can be used for accurate calibration and verification of fiber positioners with SCARA-like RR planar kinematics. It is capable of measuring accurately the abso ...

SPIE-INT SOC OPTICAL ENGINEERING2018

Anomalous Vp/Vs ratios at seismic frequencies might evidence highly damaged rocks in subduction zones

Marie Estelle Solange Violay, Lucas Xan Pimienta

Unusually high compressional (P) to shear (S) wave velocity ratios (V-p/V-s) were measured at different subduction zones and interpreted as fluid-pressurized regions. Because no laboratory data reported such high values in isotropic rocks, mineralogical or ...

2018

Ultra-low noise microwave signal generation with an optical frequency comb

Romain Dany Bruno Bouchand

Photonic synthesis of radio frequency waveforms revived the quest for unrivalled microwave purity by its seducing ability to convey the benefits of the optics to the microwave world. In this contribution, we will present a high-fidelity transfer of frequen ...

SPIE-INT SOC OPTICAL ENGINEERING2018

Chip-Scale Frequency Comb Generators for High-Speed Communications and Optical Metrology

Tobias Kippenberg, Maxim Karpov, Arne Kordts, Victor Brasch

Chip-scale frequency comb sources are key elements for a variety of applications, comprising massively parallel optical communications and high-precision optical metrology. In this talk, we give an overview on our recent progress in the area of integrated ...

Spie-Int Soc Optical Engineering2017

Scanning Gate Microscope for Cold Atomic Gases

Jean-Philippe Brantut

We present a scanning probe microscopy technique for spatially resolving transport in cold atomic gases, in close analogy with scanning gate microscopy in semiconductor physics. The conductance of a quantum point contact connected to two atomic reservoirs ...

2017

Design, analysis, testing and applications of two-body and three-body kinematic mounts

Johannes Richard Cornelis Geerit Kruis

Kinematic couplings are used when two rigid bodies need to be repeatedly and accurately positioned with respect to each other. They allow for sub-micron positioning repeatability by suppressing play and reducing strains in the bodies. Typical applications ...

EPFL2016

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

Photonic chip-based optical frequency comb using soliton Cherenkov radiation

Tobias Kippenberg, Martin Hubert Peter Pfeiffer, Victor Brasch, Tobias Herr, Michael Wolfgang Geiselmann

Optical solitons are propagating pulses of light that retain their shape because nonlinearity and dispersion balance each other. In the presence of higher-order dispersion, optical solitons can emit dispersive waves via the process of soliton Cherenkov rad ...

American Association for the Advancement of Science2015

Development and integration of high straightness flexure guiding mechanisms dedicated to the METAS watt balance Mark II

Reymond Clavel, Florent Cosandier

There is a firm will in the metrology community to redefine the kilogram in the International System of units by linking it to a fundamental physical constant. The watt balance is a promising way to link the mass unit to the Planck constant h. At the Feder ...

Iop Publishing Ltd2014

Surge Wave Propagation in a Common Tailrace Channel for Two Large Pumped-Storage Plants

Anton Schleiss, Giovanni De Cesare, Martin Peter Bieri, Stéphane Christian Olivier Terrier

Sudden starting and stopping of turbines and pumps lead to highly unsteady flow in tailrace channels of hydropower plants (HPP). Submergence of Pelton turbines and air entrainment in pumps due to surge waves must be avoided by technical measures. The exist ...

Asce-Amer Soc Civil Engineers2014

Compact High-Performance Continuous-Wave Double-Resonance Rubidium Standard With 1.4 x 10(-13) tau(-1/2) Stability

Anja Skrivervik, Francesco Merli, Camillo Stefanucci

We present our studies on a compact high-performance continuous wave (CW) double-resonance (DR) rubidium frequency standard in view of future portable applications. Our clock exhibits a short-term stability of 1.4 x 10(-13) tau(-1/2), consistent with the s ...

Institute of Electrical and Electronics Engineers2014

Updated measurements of exclusive J/psi and psi(2S) production cross-sections in pp collisions at root s=7 TeV

Jian Wang, Olivier Schneider, Yiming Li, Yi Zhang, Lei Zhang, Aurelio Bay, Guido Haefeli, Jessica Prisciandaro, Tatsuya Nakada, Christoph Frei, Mark Tobin, Frédéric Blanc, Minh Tâm Tran, Michel De Cian, Greig Alan Cowan, Maurizio Martinelli, Vladislav Balagura, Donal Patrick Hill, Liang Sun, Pietro Marino, Luca Pescatore, Jean Wicht, Ilya Komarov, Bastien Luca Muster, Frédéric Guillaume Dupertuis, Julien Rouvinet, Pierre Jaton, Barinjaka Rakotomiaramanana, Joël Bressieux, Songmei Wu, Raluca Anca Muresan, Johan Luisier

The differential cross-section as a function of rapidity has been measured for the exclusive production of J/psi and psi(2S) mesons in proton-proton collisions at root s = 7 TeV, using data collected by the LHCb experiment, corresponding to an integrated l ...

Iop Publishing Ltd2014

Publications associées (23)