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Orientation-dependent two-dimensional magnonic crystal modes in an ultralow-damping ferrimagnetic waveguide containing repositioned hexagonal lattices of Cu disks

Two-dimensional (2D) hexagonal lattices of Cu disks are shown to induce orientation-dependent magnonic crystal (MC) modes for propagating forward volume spin waves in a single-crystal yttrium iron garnet (YIG) film. The width and depth of the magnonic band ...

American Physical Society (APS)2024

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

A 0.14-nJ/b 200-Mb/s 2.7-3.5-GHz Quasi-Balanced FSK Transceiver With PLL-Based Modulation and Sideband Energy Detection

Cong Ding, Bowen Wang

This paper describes a balanced frequency shift keying (FSK) modulation, namely quasi-balanced FSK (QB-FSK), for energy-efficient high-data-rate communication. Not suffering from data-pattern dependency, the proposed modulation method enables frequency mod ...

2024

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

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

Tri-Axial Magnetic Field Sensor up to VHF with Frequency Weighing

German Augusto Ramirez Arroyave

This contribution presents an isotropic magnetic field probe with shaped frequency response in the band 100 kHz - 400 MHz to ponder the aggregate response according to the ICNIRP 2020 guidelines. The basic sensor is a printed loop which is modelled as a Th ...

IEEE2023

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

Comparison of Different Formulations to Compute the Ground Return Parameters in the Analysis of High-Frequency Pulse Propagation Along a Wire Above a Lossy Ground

Farhad Rachidi-Haeri, Rafael Silva Alipio

The propagation characteristics along a single-conductor line above a lossy ground are assessed considering different formulations to compute the ground correction terms in the per-unit-length line parameters. It is shown that the often-used Sunde’s formul ...

2023

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

Metasurface Near-Field Measurements with Incident Field Reconstruction Using a Single Horn Antenna

Shourya Dutta Gupta, Ville Tuovi Tiukuvaara

Metasurfaces (MSs) are the 2-D equivalent of metaterials, the latter being a class of artificial engineered materials exhibiting peculiar electromagnetic properties [1], [2]. Generally constructed as arrays of deeply sub-wavelength resonant particles on a ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Corona discharge actuator as an active sound absorber under normal and oblique incidence

Hervé Lissek, Stanislav Sergeev, Thomas Humbert

In the majority of active sound absorbing systems, a conventional electrodynamic loudspeaker is used as a controlled source. However, particular situations may require an actuator that is more resistant to harsh environments, adjustable in shape, and light ...

2022

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

Dipole-Fed Rectangular Dielectric Resonator Antennas for Magnetic Resonance Imaging at 7 T: The Impact of Quasi-Transverse Electric Modes on Transmit Field Distribution

Rolf Gruetter, Daniel Wenz

Shortened dipole antennas based on rectangular dielectric blocks play an important role in ultrahigh field magnetic resonance imaging (UHF-MRI) radio frequency (RF) coil design. However, the generally assumed direct contact with the subject is difficult to ...

2021

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

The effect of low-frequency equalisation on preference and sensorimotor synchronisation in music

Steffen Alexander Herff

Equalisation, a signal processing technique commonly used to shape the sound of music, is defined as the adjustment of the energy in specific frequency components of a signal. In this work, we investigate the effects of equalisation on preference and senso ...

SAGE PUBLICATIONS LTD2021

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

Energy-Efficient Design Techniques for High-Speed Wireline Serial Links

Firat Çelik

The exponential growth in computing power and multimedia services has caused a tremendous increase in data traffic in recent years. This increase in data traffic brings a strong demand for data bandwidth of electrical input/output (I/O) links and pushes th ...

EPFL2021