Publications associées à Absorption (acoustics)

Massively parallel nodal discontinous Galerkin finite element method simulator for room acoustics

We present a massively parallel and scalable nodal discontinuous Galerkin finite element method (DGFEM) solver for the time-domain linearized acoustic wave equations. The solver is implemented using the libParanumal finite element framework with extensions ...

Sage Publications Ltd2023

Perfluorocarbon emulsion enhances MR-ARFI displacement and temperature in vitro: Evaluating the response with MRI, NMR, and hydrophone

Mohamed Farhat, Davide Bernardo Preso, Ryan Holman

Sonosensitive perfluorocarbon F(8)TAC(18)-PFOB emulsion is under development to enhance heating, increase thermal contrast, and reduce treatment times during focused ultrasound tumor ablation of highly perfused tissue. The emulsion previously showed enhanc ...

FRONTIERS MEDIA SA2023

Ultrabroadband sound control with deep-subwavelength plasmacoustic metalayers

Romain Christophe Rémy Fleury, Hervé Lissek, Stanislav Sergeev

Controlling audible sound requires inherently broadband and subwavelength acoustic solutions, which are to date, crucially missing. This includes current noise absorption methods, such as porous materials or acoustic resonators, which are typically ineffic ...

Nature Research2023

Robust tunable acoustic impedance control on electroacoustic resonators for aircraft noise reduction

Maxime Volery

Air traffic noise emissions are responsible for a significant part of the overall environmental noise, especially in the vicinity of airports. Exposure to environmental noise is known to negatively impact health and to be associated with cardiovascular dis ...

EPFL2023

PID-like active impedance control for electroacoustic resonators to design tunable single-degree-of-freedom sound absorbers

Hervé Lissek, Maxime Volery, Xinxin Guo

Sound absorption at low frequencies still remains a challenge in both scientific research and engineering practice. Natural porous materials are ineffective in this frequency range, as well as acoustic resonators which present too narrow bandwidth of absor ...

2022

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

A phenomenological extended-reaction boundary model for time-domain wave-based acoustic simulations under sparse reflection conditions using a wave splitting method

Jan Sickmann Hesthaven

In environmental acoustics and in room acoustics, many surfaces exhibit extended-reaction (ER) behavior, i.e., their surface impedance varies with the angle of the incident sound wave. This paper presents a phenomenological method for modeling such angle d ...

ELSEVIER SCI LTD2021

Localization of Electromagnetic Interference Sources Using a Time-Reversal Cavity

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

In this article, we propose and implement a novel technique to locate electromagnetic interference (EMI) sources using the concept of time-reversal (TR) cavity. We show in an intuitive manner that reflections from the surfaces of a cavity can emulate an in ...

2021

Improving sound absorption through nonlinear active electroacoustic resonators

Romain Christophe Rémy Fleury, Hervé Lissek, Xinxin Guo

Absorbing airborne noise at frequencies below 300 Hz is a particularly vexing problem due to the absence of natural sound absorbing materials at these frequencies. The prevailing solution for low-frequency sound absorption is the use of passive narrow-band ...

American Physical Society (APS)2020

Low frequency sound field reconstruction in a non-rectangular room using a small number of microphones

Hervé Lissek, Vu Thach Pham

An accurate knowledge of the sound field distribution inside a room is required to identify and optimally locate corrective measures for room acoustics. However, the spatial recovery of the sound field would result in an impractically high number of microp ...

2020

Point, Plane, Set, Match! Winning the Echo Grand SLAM

Miranda Krekovic

Some of the most important and challenging problems in science are inverse problems. They allow us to understand phenomena that cannot be measured directly. Inverse problems might not always have a unique or stable solution, or might not have any solution ...

EPFL2020

Locating Transient Directional Sources in Free Space Based on the Electromagnetic Time Reversal Technique

Farhad Rachidi-Haeri, Marcos Rubinstein, Qi Li

Traditional location methods such as time of arrival and direction of arrival have been widely used to locate transient radiation sources. However, these approaches neglect the directional radiation pattern of the sources. Locating directional sources is a ...

2020

Is there a relationship between footstep-impact locations and measured signal characteristics?

Ian Smith, Yves Sylvain Gilles Reuland, Sai Ganesh Sarvotham Pai, Slah Drira

Building utilization can be enhanced by tracking occupants. Non-intrusive tracking of occupants using floor-vibration measurements is beneficial for many smart-building applications such as energy consumption, security enhancement, and care-giving. Also, u ...

ACM2019

Active acoustic resonators with reconfigurable resonance frequency, absorption, and bandwidth

Romain Christophe Rémy Fleury, Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Theodoros Koutserimpas

Acoustic resonators play a key role in the development of subwavelength-sized technologies capable of interacting with airborne audible sound, from its emission and absorption to its manipulation and processing. Specifically, artificial acoustic media made ...

American Physical Society (APS)2019

Multi-degree-of-freedom low-frequency electroacoustic absorbers through coupled resonators

Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Sami Driss Karkar

Electroacoustic absorbers represent an interesting solution for low-frequency sound absorption in rooms. These systems simply consist of closed-box electrodynamic loudspeakers, whose acoustic impedance at the diaphragm is judiciously adjusted by connecting ...

Elsevier2018

MULAN: A Blind and Off-Grid Method for Multichannel Echo Retrieval

Rémi Gribonval, Helena Peic Tukuljac

This paper addresses the general problem of blind echo retrieval, i.e., given M sensors measuring in the discrete-time domain M mixtures of K delayed and attenuated copies of an unknown source signal, can the echo locations and weights be recovered? This p ...

2018

Distributed analyses using distinct classes of Brillouin scatterings in optical fibres

Desmond Chow Ming Chia

Brillouin scattering is an interaction between light and sound in a material. This inelastic light scattering had been observed in the first optical fibres that were used in cross-continent communication. Via Brillouin scattering, the guided light wave in ...

EPFL2018

Pyramic: Full Stack Open Microphone Array Architecture And Dataset

René Beuchat, Robin Scheibler, Corentin Ferry

In this paper we introduce an open source and reproducible microphone array hardware design and an anechoic dataset recorded with this array. The Pyramic array has 48 microphones spread onto six identical modules connected to an FPGA-ARM combo. The arrange ...

IEEE2018

Through the Hourglass: A Faithful Audiovisual Reconstruction of the Old Montreux Casino

Martin Vetterli

In architecture, space is traditionally understood as a cumulus of forms, colors and textures that form a conceived area, or-in other words-architectural space design is mainly achieved by following visual concepts. The human experience of space, however, ...

Springer2015

Electroacoustic absorbers for the low-frequency modal equalization of a room: what is the optimal target impedance for maximum modal damping, depending on the total area of absorbers?

Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Sami Driss Karkar, Véronique Adam

Electroacoustic absorbers consist of loudspeakers, shunted with an electrical circuit designed to obtain a given acoustic impedance. Their design and principles are now well understood. Unidimensional experiments, using plane waves under normal incidence i ...

2014