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Concept

Forme d'onde

Publications associées (27)

Direct observations of X-rays produced by upward positive lightning

Farhad Rachidi-Haeri, Marcos Rubinstein, Antonio Sunjerga, Thomas Chaumont

X-rays have been observed in natural downward cloud-to-ground lightning for over 20 years and in rocket-triggered lightning for slightly less. In both cases, this energetic radiation has been detected during the stepped and dart leader phases of downward n ...

Nature Publishing Group2024

Measuring electro-adhesion pressure before and after contact

Herbert Shea, Sylvain Thomas Schaller

Electro-adhesion (EA) is a low-power, tunable, fast and reversible electrically-controlled adhesion method, effective on both conducting and insulating objects. Typically, only the electro-adhesive detachment force, i.e., the force required to separate an ...

Nature Portfolio2023

Terahertz waveform synthesis in integrated thin-film lithium niobate platform

Ileana-Cristina Benea-Chelmus

Bridging the "terahertz gap" relies upon synthesizing arbitrary waveforms in the terahertz domain enabling applications that require both narrow band sources for sensing and few-cycle drives for classical and quantum objects. However, realization of custom ...

Nature Portfolio2023

Step detection in power system waveforms for improved RoCoF and frequency estimation

Mario Paolone, Asja Derviskadic, Guglielmo Frigo, Alexandra Cameron Karpilow

The evaluation of the signal frequency and Rate of Change of Frequency (RoCoF) from voltage or current waveforms is used for critical grid control, monitoring and protection applications. However, when step changes in the amplitude or phase of the signal o ...

Elsevier2022

Study of the enhanced electricity output of a sliding droplet-based triboelectric nanogenerator for droplet sensor design

Jürgen Brugger, Xia Liu, Wei Xu

Triboelectric nanogenerators are establishing themselves as promising candidates for realizing high-efficient energy harvesting from largely available droplets. However, the conventional droplet-based liquid-solid triboelectric nanogenerator (DLS-TENG) has ...

Elsevier2022

Analytical Expressions for Lightning Electromagnetic Fields With Arbitrary Channel-Base Current—Part I: Theory

Marcos Rubinstein

The article provides analytical expressions for the electromagnetic fields generated by a lightning return stroke characterized by a channel-base current with arbitrary time waveform, in presence of either a perfectly conducting or a lossy ground, assuming ...

2021

Automated test setup to quantify the lifetime of dielectric elastomer actuators under a wide range of operating conditions

Herbert Shea, Fabio Beco Albuquerque, Djen Timo Kühnel, Valentin Colin Py

We present an automated test setup for the systematic performance and lifetime evaluation of dielectric elastomer actuators (DEAs). This setup, called the MAPLE setup, performs accelerated aging tests and allows quantifying how material choice, fabrication ...

IOP PUBLISHING LTD2021

Fundamentals of power systems modelling in the presence of converter-interfaced generation

Mario Paolone

This survey paper discusses the fundamentals of power systems modelling in the presence of large amounts of converter-interfaced generation (CIG). By referring to real-life events characterised by anomalous dynamics associated to the presence of CIG, the c ...

Elsevier2020

Quasi-Rayleigh model for modeling hysteresis of piezoelectric actuators

Dragan Damjanovic

Piezoelectric actuators (PEAs) have been widely used in nano-positioning applications for their high resolution of displacement. However, hysteresis, which is an inherent property of ferroelectric PEAs has been shown to significantly degrade the system per ...

2020

Numerical and Experimental Validation of Electromagnetic Time Reversal for Geolocation of Lightning Strikes

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

We implement an electromagnetic time reversal technique (EMTR) to locate lightning return strokes. The two-dimensional finite difference time domain is employed to simulate the EMTR process in both, the forward-time and the backward-time phases. Scatterers ...

2020

Spatial covariance improves BCI performance for late ERPs components with high temporal variability

José del Rocio Millán Ruiz, Ricardo Andres Chavarriaga Lozano, Lucian Andrei Gheorghe, Marija Uscumlic, Ruslan Aydarkhanov

Objective. Event Related Potentials (ERPs) reflecting cognitive response to external stimuli, are widely used in brain computer interfaces. ERP waveforms are characterized by a series of components of particular latency and amplitude. The classical ERP dec ...

2020

Multiple-Station Measurements of a Return-Stroke Electric Field From Rocket-Triggered Lightning at Distances of 68-126 km

Antonio Sunjerga, Quanxin Li

Far-field measurements of lightning-produced electromagnetic fields are of high importance for lightning location systems. Data from recorded lightning strokes can be, for example, used to assess the risk of lightning-induced damage in some geographical ar ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2019

Importance of Taking Into Account the Soil Stratification in Reproducing the Late-Time Features of Distant Fields Radiated by Lightning

Farhad Rachidi-Haeri, Marcos Rubinstein, Antonio Sunjerga

In this paper, we present an analysis of the propagation effect along a lossy ground on the characteristics of lightning-generated electric fields, using simultaneous observations of lightning currents and radiated fields measured at nine different distanc ...

2019

Two Possible Scenarios for the Formation of Category 1 Bipolar Lightning Flashes

Marcos Rubinstein, Davide Pavanello, Mohammad Azadifar, Quanxin Li

We present and discuss the current and electric field waveforms associated with two upward bipolar lightning flashes that occurred at the Säntis Tower. According to the traditional classification of bipolar flashes, both observed flashes could be classifie ...

2019

A stick-slip/inchworm hybrid rotary piezo motor based on a symmetric triangular driving mechanism

Dongdong Zheng

A stick-slip/inchworm hybrid rotary piezomotor based on a symmetric triangular driving mechanism, which can simultaneously achieve the benefits of both stick-slip and inchworm motors, was reported in this letter. It is based on the principle of stick-slip ...

2019

Optimization of the Beam Screen for the FCC Injection Kicker Magnets

Agnieszka Chmielinska

The Future Circular Collider for hadrons (FCC-hh) is a proposed high-energy frontier particle accelerator, which would be built in a new ~100 km circumference tunnel and would enable proton-proton collisions at a centre-of-mass energy of 100 TeV. The basel ...

EPFL2019

A New Engineering Model of Lightning M Component That Reproduces Its Electric Field Waveforms at Both Close and Far Distances

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Quanxin Li

We present a new engineering model for the M component mode of charge transfer to ground that can predict the observed electric field signatures associated with this process at various distances, including (a) the microsecond-scale pulse thought to be due ...

2019

An Analysis of Current and Electric Field Pulses Associated With Upward Negative Lightning Flashes Initiated from the Säntis Tower

Marcos Rubinstein, Davide Pavanello, Mohammad Azadifar, Lixia He

We present a study on the characteristics of current and electric field pulses associated with upward lightning flashes initiated from the instrumented Säntis Tower in Switzerland. The electric field was measured 15 km from the tower. Upward flashes always ...

2018

Method for estimating synchrophasors during static and dynamic conditions

Mario Paolone, Asja Derviskadic, Paolo Romano

A method for performing synchrophasor estimation of an input signal, whereby the input signal is a sinusoidal power system voltage or current signal, comprising: a. Periodic sampling of a continuous time-domain waveform, consisting of a power system voltag ...

2018

Area and Power Efficient Ultra-Wideband Transmitter Based on Active Inductor

Catherine Dehollain, Franco Maloberti, Kerim Türe, Arnout Jan J Devos

This paper presents the design of an impulse radio ultra-wideband (IR-UWB) transmitter for low-power, short-range, and high-data rate applications such as high density neural recording interfaces. The IR-UWB transmitter pulses are generated by modulating t ...

2018