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Multi-Frequency Tracking via Group-Sparse Optimal Transport

In this letter, we introduce an optimal transport framework for inferring power distributions over both spatial location and temporal frequency. Recently, it has been shown that optimal transport is a powerful tool for estimating spatial spectra that chang ...

Ieee-Inst Electrical Electronics Engineers Inc2024

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

Dynamic behavior of exposed geomembrane systems in pressure waterways

Giovanni De Cesare, Samuel Luke Vorlet, Roberto Proença Seixas

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

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

Lightning interaction with the ionosphere

Farhad Rachidi-Haeri, Marcos Rubinstein, Dongshuai Li

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

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

Duccio Testa, Marcus Cemes, Ambrine Douhane

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

Electronic metadevices for terahertz applications

Elison de Nazareth Matioli, Mohammad Samizadeh Nikooytabalvandani

The evolution of electronics has largely relied on downscaling to meet the continuous needs for faster and highly integrated devices(1). As the channel length is reduced, however, classic electronic devices face fundamental issues that hinder exploiting ma ...

NATURE PORTFOLIO2023

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

Artificial Neural Network Training on an Optical Processor via Direct Feedback Alignment

Florent Gérard Krzakala, Julien Marcel Daniel Emmanuel Launay

Artificial Neural Networks (ANN) are habitually trained via the back-propagation (BP) algorithm. This approach has been extremely successful: Current models like GPT-3 have O(10 11 ) parameters, are trained on O(10 11 ) words and produce awe-inspiring resu ...

IEEE2023

A single-beat algorithm to discriminate farfield from nearfield bipolar voltage electrograms from the pulmonary veins

Jean-Marc Vesin, Adrian Luca, Vincent Schlageter

Background Superimposition of farfield (FF) and nearfield (NF) bipolar voltage electrograms (BVE) complicates the confirmation of pulmonary vein (PV) isolation after catheter ablation of atrial fibrillation. Our aim was to develop an automatic algorithm ba ...

SPRINGER2023

Development of next-generation microfluidic systems for enhanced, faster, and cost-effective immunoassays for tissue diagnostics - Ac electrothermal flow & Acoustofluidics

Muaz Salama Abdelmonem Draz

The application of microfluidics in the field of surface-based assays and more specifically, the spatial molecular profiling of tumor tissues has gained a lot of interest, especially with the increased interest in personalized medicine and targeted therapy ...

EPFL2023

Low and high frequency electromagnetic forces: numerical modelling and practical applications

Marco Riccardi

The understanding and manipulation of nanoscale analytes is a central theme in nanotechnology and has been one of the main driving forces behind the development of this field as we know it today. Furthermore, such a technology has the potential to also rev ...

EPFL2022

The spectral bias of polynomial neural networks

Volkan Cevher, Grigorios Chrysos, Leello Tadesse Dadi, Moulik Choraria

Polynomial neural networks (PNNs) have been recently shown to be particularly effective at image generation and face recognition, where high-frequency information is critical. Previous studies have revealed that neural networks demonstrate a spectral bias ...

2022

Generation of OAM-carrying space-time wave packets with time-dependent beam radii using a coherent combination of multiple LG modes on multiple frequencies

Tobias Kippenberg, Maxim Karpov, Zhe Zhao, Hao Song, Xinzhou Su

Space-time (ST) wave packets, in which spatial and temporal characteristics are coupled, have gained attention due to their unique propagation characteristics, such as propagation invariance and tunable group velocity in addition to their potential ability ...

Optica Publishing Group2022

Millimeter-wave to near-terahertz sensors based on reversible insulator-to-metal phase transition in Vanadium dioxide

Fatemeh Qaderi Rahaqi

Millimeter-wave (mm-wave) and terahertz (THz) detection has opened a significant research direction in imaging, sensing, spectroscopy, and ultrafast wireless communication. The sensitivity of the phase transition to electromagnetic waves in Vanadium dioxid ...

EPFL2022

Transient Elastomers with High Dielectric Permittivity for Actuators, Sensors, and Beyond

Holger Frauenrath, Yauhen Sheima

Dielectric elastomers (DEs) are key materials in actuators, sensors, energy harvesters, and stretchable electronics. These devices find applications in important emerging fields such as personalized medicine, renewable energy, and soft robotics. However, e ...

AMER CHEMICAL SOC2022

Development of Thin Film Lithium Niobate Shear Bulk Acoustic Wave Resonators

Soumya Yandrapalli

RF MEMS piezoelectric acoustic resonators are the essential building blocks for RF filters used in RF front-end modules for wireless mobile communication due to their compact size in the MHz-GHz frequency range, high Quality factors and large relative band ...

EPFL2022

Constraining quasar structure using high-frequency microlensing variations and continuum reverberation

Frédéric Courbin, Eric Gérard Guy Paic, Hung-Hsu Chan, Vivien François Bonvin, Georgios Vernardos, Martin Raoul Robert Millon

Gravitational microlensing is a powerful tool for probing the inner structure of strongly lensed quasars and for constraining parameters of the stellar mass function of lens galaxies. This is achieved by analysing microlensing light curves between the mult ...

EDP SCIENCES S A2022

Plasma-based Electroacoustic Actuator for Broadband Sound Absorption

Stanislav Sergeev

Environmental noise, mostly related to human activities, has an immense impact on public health. The development of noise reduction technologies is paramount in addressing this problem. Because of practical and economic reasons, a compact, broadband, light ...

EPFL2022

Hybrid Modular Multilevel Converter for Pumped Hydro Storage Applications

Miodrag Basic

Energy balance in a power system must be maintained at all times, regardless of the variations in generation and consumption. Large Pumped Hydro Storage Plants (PHSPs) are introduced to the power system to accumulate the excess of energy during the low dem ...

EPFL2022