Publications associées à Piezoelectric Actuators Characterization

Impact of beam-coupling impedance on the Schottky spectrum of bunched beam

Tatiana Pieloni, Nicolas Frank Mounet, Christophe Emmanuel R. Lannoy

The Schottky monitors of the Large Hadron Collider (LHC) can be used for non-invasive beam diagnostics to estimate various bunch characteristics, such as tune, chromaticity, bunch profile or synchrotron frequency distribution. However, collective effects, ...

Iop Publishing Ltd2024

A Two-Wired High Input Impedance and High CMRR Active Electrode Insensitive to Component Mismatch

Alexandre Schmid, Mehdi Saberi

This article proposes a new two-wired amplifying active electrode (AE), presenting a high input impedance and a high common-mode rejection ratio (CMRR). In the proposed structure, the input impedance and the CMRR of the system are considerably increased by ...

Ieee-Inst Electrical Electronics Engineers Inc2024

On the use of Cramér-Rao Lower Bound for least-variance circuit parameters identification of Li-ion cells

Mario Paolone, Vladimir Sovljanski

Electrochemical Impedance Spectroscopy (EIS) and Equivalent Circuit Models (ECMs) are widely used to characterize the impedance and estimate parameters of electrochemical systems such as batteries. We use a generic ECM with ten parameters grouped to model ...

2024

High-frequency response of a hemispherical grounding electrode

Farhad Rachidi-Haeri, Marcos Rubinstein, Antonio Sunjerga

The lightning discharge current is characterized by a high-frequency spectrum extending from DC to about 10 MHz. The calculation of the grounding impedance is one of the most important aspects of designing lightning protection systems. The search for analy ...

Elsevier2024

A ride time-oriented scheduling algorithm for dial-a-ride problems

Nikolaos Geroliminis, Claudia Bongiovanni, Mor Kaspi

This paper offers a new algorithm to efficiently optimize scheduling decisions for dial-a-ride problems (DARPs), including problem variants considering electric and autonomous vehicles (e-ADARPs). The scheduling heuristic, based on linear programming theor ...

Pergamon-Elsevier Science Ltd2024

Inversing the actuation cycle of dielectric elastomer actuators for a facial prosthesis

Paolo Germano, Yves Perriard, Yoan René Cyrille Civet, Alexis Boegli, Thomas Guillaume Martinez, Stefania Maria Aliki Konstantinidi, Quentin Philippe Mario De Menech

Dielectric Elastomer Actuators (DEAs) are a type of smart material described as compliant capacitors. They show impressive performances as soft actuators, such as a high strain and fast response. Nonetheless, replicating natural muscle function with DEAs h ...

Society of Photo-Optical Instrumentation Engineers (SPIE)2024

Optimization Algorithms for Decentralized, Distributed and Collaborative Machine Learning

Anastasiia Koloskova

Distributed learning is the key for enabling training of modern large-scale machine learning models, through parallelising the learning process. Collaborative learning is essential for learning from privacy-sensitive data that is distributed across various ...

EPFL2024

Permanently magnetized elastomer rotating actuator using traveling waves

Herbert Shea

We report a soft actuator that generates continuous rotation of an object placed on it by electromagnetically exciting circular travelling waves in a soft disk. The disk, that serves as the stator, is made of a stretchable composite consisting of segments ...

Iop Publishing Ltd2024

The effect of smooth parametrizations on nonconvex optimization landscapes

Nicolas Boumal

We develop new tools to study landscapes in nonconvex optimization. Given one optimization problem, we pair it with another by smoothly parametrizing the domain. This is either for practical purposes (e.g., to use smooth optimization algorithms with good g ...

Springer Heidelberg2024

Ripple Voltage and Loss Reduction of Single-Phase ISOP SST by Eliminating the Second Harmonic Current in LLC Converters

Drazen Dujic, Tianyu Wei, Andrea Cervone

In two-stage solid-state transformers with input-series output-parallel structure, the LLC converter operating at a fixed switching frequency is a common choice for the isolated DC/DC conversion stage because it can provide a high efficiency and a fixed vo ...

2024

Polarization-enhanced GaN Schottky barrier diodes: Ultra-thin InGaN for high breakdown voltage and low Ron

Elison de Nazareth Matioli, Alessandro Floriduz, Zheng Hao

In this work, we present a concept that leverages the strong piezoelectric polarization field in InGaN, which counteracts the external electric field at reverse bias. We show that despite the smaller InGaN band-gap and lower critical electric field, its st ...

2024

Modeling and optimization of PCB coils for inductive power transfer systems

Xiaotong Du

The auxiliary power supply for medium voltage converters requires high insulation capability between the source and the load. Inductive power transfer technology, with an air gap between the primary and secondary coil, offers such high insulation capabilit ...

EPFL2024

Portable impedance-sensing device for microorganism characterization in the field

Sandro Carrara, Karim Bouzid

A variety of biosensors have been proposed to quickly detect and measure the properties of individual microorganisms among heterogeneous populations, but challenges related to cost, portability, stability, sensitivity, and power consumption limit their app ...

Nature Portfolio2023

Self-Synchronized Grid Impedance Estimation Unit using Interpolated DFT Technique

Drazen Dujic, Jules Christian Georges Macé, Andrea Cervone

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

Stochastic adaptive resampling for the estimation of discrete choice models

Michel Bierlaire, Nicola Marco Ortelli, Matthieu Marie Cochon de Lapparent

In the field of choice modeling, the availability of ever-larger datasets has the potential to significantly expand our understanding of human behavior, but this prospect is limited by the poor scalability of discrete choice models (DCMs): as sample sizes ...

2023

NbN films with high kinetic inductance for high-quality compact superconducting resonators

Edoardo Charbon, Simone Frasca, Pasquale Scarlino, Vincent Jean Yves Jouanny, Fabian Oppliger, Fabrizio Minganti, Marco Scigliuzzo, Roberto Musio

Niobium nitride (NbN) is a particularly promising material for quantum technology applications, as it shows the degree of reproducibility necessary for large-scale superconducting circuits. We demonstrate that resonators based on NbN thin films present a o ...

American Physical Society (APS)2023

Bayesian Optimization for Chemical Reactions

Philippe Schwaller, Bojana Rankovic, Jeff Guo

Reaction optimization is challenging and traditionally delegated to domain experts who iteratively pro-pose increasingly optimal experiments. Problematically, the reaction landscape is complex and often requires hundreds of experiments to reach convergence ...

Swiss Chemical Soc2023

A combined genetic algorithm and active learning approach to build and test surrogate models in Process Systems Engineering

François Maréchal, Julia Granacher

In Process Systems Engineering, computationally-demanding models are frequent and plentiful. Handling such complexity in an optimization framework in a fast and reliable way is essential, not only for generating meaningful solutions but also for providing ...

Pergamon-Elsevier Science Ltd2023

Electrode Impact on the Electrical Breakdown of Dielectric Elastomer Thin Films

Herbert Shea, Fabio Beco Albuquerque

Dielectric Elastomer Actuators (DEAs) enable the realization of energy-efficient and compact actuator systems. DEAs operate at the kilovolt range with typically microampere-level currents and hence minimize thermal losses in comparison to low voltage/high ...

MDPI2023

Wind farm power density optimization according to the area size using a novel self-adaptive genetic algorithm

Fernando Porté Agel, Nicolas Otto Kirchner Bossi

This work studies the power density (PD) optimization in wind farms, and its sensitivity to the available area size. A novel genetic algorithm (PDGA) is introduced, which optimizes PD and the turbine layout, by self-adapting to the PD and to the solutions ...

Pergamon-Elsevier Science Ltd2023