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Publications associées (28)

Smart Acoustic Lining for UHBR Technologies Engine Part 1: Design of an Electroacoustic Liner and Experimental Characterization Under Flow in Rectangular Cross-Section Ducts

Hervé Lissek, Maxime Volery

The new generation of Ultra-High-By-Pass-Ratio (UHBR) turbofan engine while considerably reducing fuel consumption, threatens higher noise levels at low frequencies because of its larger diameter, lower number of blades and rotational speed. This is accomp ...

American Institute of Aeronautics and Astronautics2024

Deriving Major Ion Concentrations at High Resolution from Continuous Electrical Conductivity Measurements in Karst Systems

Paolo Benettin

Time series of hydrochemical parameters support the investigation of dominant karst hydrological processes and conceptual model structures. Nevertheless, high costs for sample collection and analyses cause hydrochemical data to be rarely available at a suf ...

SPRINGER INTERNATIONAL PUBLISHING AG2023

First developments towards producing inductive magnetic sensors using state-of-the-art photolithography techniques

Duccio Testa, Ambrine Douhane, Marcus Cemes

Inductive magnetic sensors are needed for tokamak operation to provide the low-frequency (LF) measurements leading to the equilibrium reconstruction and to monitor the higher frequency (HF) instabilities; the HF magnetic sensors are often also used as a ba ...

2023

Dynamic behavior of exposed geomembrane systems in pressure waterways

Giovanni De Cesare, Samuel Luke Vorlet

Geomembrane systems have been used in dams and reservoirs as rehabilitation technology since several decades and are now used worldwide. They act as impervious layer to prevent and mitigate water leakage and damage to structures. They meet the needs of man ...

CRC Press/Balkema2023

Lightning interaction with the ionosphere

Farhad Rachidi-Haeri, Marcos Rubinstein

Lightning discharges, including cloud-to-ground (CG) and intracloud (IC) lightning, are known to emit electromagnetic pulses (EMPs) in a wide frequency band ranging from few Hz up to hundreds MHz [1]. During the breakdown and ionization processes (mostly f ...

IET2023

Self-Synchronized Grid Impedance Estimation Unit using Interpolated DFT Technique

Drazen Dujic, Andrea Cervone, Jules Christian Georges Macé

Estimating the impedance of a grid-connected device or of a grid at the point of common coupling is important for evaluating the interaction between them. Impedance measurement involves a perturbation injection device, that perturbs the system, and a measu ...

2023

Emittance growth suppression with a multibunch feedback in high-energy hadron colliders: Numerical optimization of the gain and bandwidth

Xavier Buffat, Sondre Vik Furuseth

A transverse feedback system can effectively mitigate the emittance growth caused by injection oscillations and machine noise in hadron beams. However, as its action on the beam depends on beam position measurements of finite accuracy, it introduces additi ...

2021

High-frequency broadband laser phase noise cancellation using a delay line

Timo Zwettler

Laser phase noise remains a limiting factor in many experimental settings, including metrology, time-keeping, as well as quantum optics. Hitherto this issue was addressed at low frequencies ranging from well below 1 Hz to maximally 100 kHz. However, a wide ...

2021

Sound Field Reconstruction in a room through Sparse Recovery and its application in Room Modal Equalization

Vu Thach Pham

The acoustics of a room often refer to the quality of the room in terms of sound recording as well as sound reproduction. At low frequencies, where the wavelengths are of the same order of magnitude with the dimensions of the room, due to the standing wave ...

EPFL2021

Association of Heart Rate Variability With Silent Brain Infarcts in Patients With Atrial Fibrillation

Jean-Marc Vesin, Vincent Schlageter

Purpose: Silent brain infarcts (SBI) are frequently detected in patients with atrial fibrillation (AF), but it is unknown whether SBI are linked to autonomic dysfunction. We aimed to explore the association of autonomic dysfunction with SBI in AF patients. ...

FRONTIERS MEDIA SA2021

Machine Learning-Based Lightning Localization Algorithm Using Lightning-Induced Voltages on Transmission Lines

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Amirhossein Mostajabi, Hamidreza Karami

In this article, we present a machine learning-based method to locate lightning flashes using calculations of lightning induced voltages on a transmission line. The proposed approach takes advantage of the preinstalled voltage measurement systems on power ...

2020

Design and Optimization of Low Power and Low Light Sensor

Christian Enz, Assim Boukhayma, Antonino Caizzone, Raffaele Capoccia

The current trend towards embedding more and more light sensors in portable and wearable devices is calling for higher integration and reuse of the sensor interface electronics. In many applications, the light needs to be generated locally, which becomes t ...

IEEE2020

Single yeast cell nanomotions correlate with cellular activity

Giovanni Dietler, Sandor Kasas, María Inés Villalba, Anton Malovichko

Living single yeast cells show a specific cellular motion at the nanometer scale with a magnitude that is proportional to the cellular activity of the cell. We characterized this cellular nanomotion pattern of nonattached single yeast cells using classical ...

AMER ASSOC ADVANCEMENT SCIENCE2020

Antennas for CubeSat Communication

Miroslav Veljovic

CubeSats are a type of small satellites (< 500 kg) that weigh several kilograms and consist of multiple Units (U) measuring 100 × 100 × 113.5 mm3. CubeSats emerged as a low-cost alternative to conventional large satellites, and have since demonstrated capa ...

EPFL2020

Biotechnologies to tackle the challenge of neoantigen identification

Philippe Renaud, George Coukos, Alexandre Harari, Margaux Catherine Marie Duchamp

Among immune correlates of clinical responses, tumor-specificneoantigens took the spotlight as relevant targets for cancerimmunotherapy. The implementation of pipelines forpersonalized cancer therapy remains challenging due to theprivacy, that is patient-s ...

2020

Theory for the density of interacting quasilocalized modes in amorphous solids

Matthieu Wyart, Thomas Willem Jan de Geus, Marko Popovic, Wencheng Ji

Quasilocalized modes appear in the vibrational spectrum of amorphous solids at low frequency. Though never formalized, these modes are believed to have a close relationship with other important local excitations, including shear transformations and two-lev ...

AMER PHYSICAL SOC2019

Nonlinear piezoelectric vibration energy harvester with frequency-tuned impacting resonators for improving broadband performance at low frequencies

Nico de Rooij, Danick Briand, Andres Felipe Vasquez Quintero, Robert Andrew Lockhart

The paper reports on a nonlinear frequency up-converting vibration energy harvester with enhanced broadband performance below 50 Hz, which is attained by leveraging vibro-impact interaction between two high-frequency piezoelectric generators and two low-fr ...

IOP PUBLISHING LTD2019

AltitudeOmics: Spontaneous Baroreflex Sensitivity During Acclimatization to 5,260 m: A Comparison of Methods

Jean-Marc Vesin, Sasan Yazdani

Introduction Baroreflex sensitivity (BRS) is essential to ensure rapid adjustment to variations in blood pressure (BP). Spontaneous baroreflex function can be assessed using continuous recordings of blood pressure. The goal of this study was to compare fou ...

2019

Tower and Path-Dependent Voltage Effects on the Measurement of Grounding Impedance for Lightning Studies

Marcos Rubinstein, Antonio Sunjerga, Hamidreza Karami, Keyhan Sheshyekani

We present an analysis aimed at evaluating the effect of the presence of the tower on the measurement of the grounding impedance. The Numerical Electromagnetics Code NEC-4 is used for the full-wave modeling of the structure including the tower and its foot ...

2019

Multi-Variable High-Frequency Input-Admittance of Grid-Connected Converters: Modeling, Validation and Implications on Stability

Drazen Dujic, Francisco Daniel Freijedo Fernández

Modern grids are facing a massive integration of power electronics devices, usually associated to instability issues. In order to assess the likelihood and severity of harmonic instability in the high frequency region, this work develops a multi-variable i ...

2019