Publications associées à Three-phase medium model for filled rock joint and interaction with stress waves

Optothermal shaping of lamb waves with square and spiral phase fronts

Romain Christophe Rémy Fleury, Aleksi Antoine Bossart, Janez Rus

We introduce a Lamb-wave medium with tunable propagation velocities, which are controlled by a two-dimensional heating pattern produced by a laser beam. We utilized it to demonstrate that waves in an appropriately designed medium can propagate in the form ...

2024

In-Sensor Passive Speech Classification with Phononic Metamaterials

Luis Guillermo Villanueva Torrijo, Daniel Moreno Garcia

Mitigating the energy requirements of artificial intelligence requires novel physical substrates for computation. Phononic metamaterials have vanishingly low power dissipation and hence are a prime candidate for green, always-on computers. However, their u ...

Wiley-V C H Verlag Gmbh2024

Optimization of elastic wave propagation in a reconfigurable medium by genetic algorithms with adaptive mutation probability

Romain Christophe Rémy Fleury, Janez Rus

We introduce a reconfigurable medium for the manipulation of elastic propagation properties of Lamb waves. It is based on a shape memory polymer (SMP) with temperature-dependent Young's modulus. Waves are excited by a laser pulse and detected by a laser vi ...

IOP Publishing Ltd2023

Fluid flow through microcracked and fractured granitic reservoirs

Marie Estelle Solange Violay, Michael Heap, Lucille Jocelyne Nadine Carbillet

The permeability of crustal rocks and rock-masses dictates the efficiency of hydrothermal circulation and therefore the productivity of geothermal resources. In this study, we find by monitoring P-wave velocity that thermal microcracking in Lanhélin granit ...

2023

Nonlinear interactions of ion acoustic waves explored using fast imaging decompositions

Fast camera imaging is used to study ion acoustic waves propagating azimuthally in a magnetized plasma column. The high-speed image sequences are analyzed using proper orthogonal decomposition and 2D Fourier transform, allowing to evaluate the assets and d ...

2023

Automatic and high-precision microseismic monitoring of progressive failure prior, during, and after tunnel excavation

Brice Tanguy Alphonse Lecampion, Christophe Nussbaum, Seyyedmaalek Momeni

Acoustic emission (AE) monitoring is commonly used to inspect the health of a structure continuously. During fracture processes elastic waves of AE are created and emitted, and sensors can capture these waves. The acquired signals can be processed to track ...

2023

Experimental study on velocity distributions, secondary currents, and coherent structures in open channel flow with submerged riparian vegetation

Haoran Shi

Riparian vegetation, which is commonly found in natural rivers and open channels, has a strong influence on flow structures. This paper describes a laboratory experiment on velocity distributions, secondary currents, and coherent structures in narrow open- ...

ELSEVIER SCI LTD2023

Long-distance coherent propagation of magnon polarons in a ferroelectric-ferromagnetic heterostructure

Jean-Philippe Ansermet, Haiming Yu, Peng Chen, Song Liu, Jilei Chen, Jianyu Zhang, Jinlong Wang, Yao Zhang

We experimentally demonstrate the coherent propagation of magnon polarons, the hybridized excitations formed by the coupling of spin waves and Rayleigh/Love surface acoustic waves, in a heterostructure consisting of ferroelectric BaTiO3 and ferromagnetic L ...

Amer Physical Soc2023

Stochastic particle transport by deep-water irregular breaking waves

Debbie Eeltink

Correct prediction of particle transport by surface waves is crucial in many practical applications such as search and rescue or salvage operations and pollution tracking and clean-up efforts. Recent results by Deike et al. (J. Fluid Mech., vol. 829, 2017, ...

Cambridge University Press2023

A 5G n77 Filter Using Shear Bulk Mode Resonator With Crystalline X-cut Lithium Niobate Films

Luis Guillermo Villanueva Torrijo, Florian Fernand Hartmann

This paper presents the use of a shear bulk acoustic mode resonator made of a membrane of X-cut lithium niobate (LiNbO3) for ultra-wide band filter applications. Aluminum interdigitated (IDT) electrodes are deposited on top of the LiNbO3 thin film as well ...

IEEE2023

Automatic and high-precision acoustic emission-based structural health monitoring of concrete structures

Brice Tanguy Alphonse Lecampion, Seyyedmaalek Momeni

Acoustic emission (AE) monitoring is a useful technique to monitor the health of a structure continuously, helping to prevent potential failure. AE are elastic waves produced and emitted during fracture processes inside a material and are recorded by senso ...

DESTech publications inc.2023

Toward Metantennas: Metamaterial-Based Antennas for Wireless Communications

Yuanyan Su

Antennas have historically been the most common electromagnetic (EM) technology for wireless communication systems. Antenna as hardware is entirely dependent on the EM properties of the materials used, mostly related to the permittivity and permeability. I ...

Ieee-Inst Electrical Electronics Engineers Inc2023

Development of a Robotic Microsurgeon for Embryonic Research

Ece Özelçi

Understanding how biological matter takes its shape is instrumental to biology, bioengineering, medicine, and bioinspired engineering. Gaining information on the principles of morphogenesis could enable clinicians to correct developmental abnormalities, ev ...

EPFL2023

Generalised Kerr Microcomb Physics in Synchronously Driven Systems

Miles Henry Anderson

In this thesis, the generation of microcombs under complex, non-trivial, and/or higher-order cavity conditions is explored, both in theory & simulation, and in practical experimentation. Pulse-driving of microresonators is investigated for the generation ...

EPFL2023

Scattering from Time-Modulated Transmission-Line Loads: Theory and Experiments in Acoustics

Romain Christophe Rémy Fleury, Matthieu Francis Malléjac

Scattering wave systems that are periodically modulated in time offer many new degrees of freedom to control waves in both the spatial and frequency domains. Such systems, albeit linear, do not conserve frequency and require the adaptation of the usual the ...

American Physical Society (APS)2023

Theoretical Efficiency and Dosimetry of Buffered On-body Transmitter Antennas for Wireless Powering of In-body Devices

Anja Skrivervik, Denys Nikolayev

The viable and safe application of wireless power transfer for powering bioelectronic implants requires understanding the wave propagation in heterogeneous and dispersive media, the electromagnetic exposure assessment, and the optimum design of the system ...

IEEE2022

cRacklet: a spectral boundary integral method library for interfacial rupture simulation

Jean-François Molinari, Fabian Barras, Thibault Didier Roch

The study of dynamically propagating rupture along interfaces is of prime importance in various fields and system sizes, including tribology (nm to m), engineering (mm to m) and geophysics (m to km) (Armstrong-Hélouvry et al., 1994; Ben-Zion, 2008; Vanossi ...

2022

Finite element method–discrete element method bridging coupling for the modeling of gouge

Jean-François Molinari, Guillaume Anciaux, Manon Eugénie Voisin--Leprince, Antonio Joaquin Garcia Suarez

We discuss the multiscale modeling of a granular material trapped between continuum elastic domains. The amorphous granular region, usually termed “gouge,” is under high confinement pressure, to represent the loading of faults at depth. We model the granul ...

Wiley2023

Reduced basis methods for numerical room acoustic simulations with parametrized boundaries

Jan Sickmann Hesthaven, Hermes Sampedro Llopis

The use of model-based numerical simulations of wave propagation in rooms for engineering applications requires that acoustic conditions for multiple parameters are evaluated iteratively, which is computationally expensive. We present a reduced basis metho ...

ACOUSTICAL SOC AMER AMER INST PHYSICS2022

Uncertainty Quantification by Multilevel Monte Carlo and Local Time-Stepping for Wave Propagation

Fabio Nobile

Because of their robustness, efficiency, and non intrusiveness, Monte Carlo methods are probably the most popular approach in uncertainty quantification for computing expected values of quantities of interest. Multilevel Monte Carlo (MLMC) methods signific ...

2022