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Related publications (23)

A technique for non-intrusive greedy piecewise-rational model reduction of frequency response problems over wide frequency bands

In the field of model order reduction for frequency response problems, the minimal rational interpolation (MRI) method has been shown to be quite effective. However, in some cases, numerical instabilities may arise when applying MRI to build a surrogate mo ...

2022

Step Change Detection for Improved ROCOF Evaluation of Power System Waveforms

Mario Paolone, Asja Derviskadic, Guglielmo Frigo, Alexandra Cameron Karpilow

In the analysis of power grid waveforms, the presence of amplitude or phase steps can disrupt the estimation of frequency and rate-of-change-of-frequency (ROCOF). Standard methods based on phasor-models fail in the extraction of signal parameters during th ...

IEEE2022

A Vibrational Technique for in vitro Intraoperative Prosthesis Fixation Monitoring

Kamiar Aminian, Hooman Dejnabadi, Seyed Abdolmajid Yousefsani

Objective: In this paper, a new vibrational modal analysis technique was developed for intraoperative cementless prosthesis fixation evaluation upon hammering. Methods: An artificial bone (Sawbones)-prosthesis system was excited by sweeping of a sine signa ...

2020

Vibration tests on interconnected timber elements using wood-wood connections

Yves Weinand, Julien Gamerro, Jean-François Bocquet

Vibration tests were performed on 3 large-scale timber slabs using wood-wood connections with a span of 8.1 meters. 10 impulsive vibration tests per specimen were performed to estimate the initial natural frequency. Vibrations were triggered using a hammer ...

2019

Vibration Mode of MEMS Ultrasonic Sensors on Buckled Diaphragms with Piezoelectric Resonance Frequency Modification

Paul Muralt, Kaoru Yamashita

Vibration mode and resonance frequency of piezoelectric MEMS ultrasonic sensors was investigated on buckled diaphragm structures. The buckling of the diaphragms was introduced intrinsically through residual stress control of the piezoelectric film, and ext ...

IEEE2019

Acoustic emission and ultrasonic testing for fatigue damage detection in a RC bridge deck slab

Eugen Brühwiler, Imane Bayane

There is a significant need to examine precisely the conditions of concrete road bridges because of the increasing traffic and axle loads and the fact that most existing bridges were not designed with respect to fatigue. In-situ investigations are challeng ...

2019

High-Resolution fMRI of Auditory Cortical Map Changes in Unilateral Hearing Loss and Tinnitus

Stephanie Clarke, Dimitri Nestor Alice Van De Ville, Wietske Van der Zwaag, Naghmeh Ghazaleh, Melissa Saenz

Animal models of hearing loss and tinnitus observe pathological neural activity in the tonotopic frequency maps of the primary auditory cortex. Here, we applied ultra high-field fMRI at 7 T to test whether human patients with unilateral hearing loss and ti ...

Springer Verlag2017

High resolution eddy current inspection and eddy current testing for additive manufacturing

David Florian Hippert

Non-destructive testing (NDT) is one of the key method developed for the safety mechanism of many industrial fields, e.g. aerospace, oil and gas and power industries. Among the NDT techniques, eddy current testing belongs to the well-established ones and h ...

EPFL2016

Investigating The Size-Dependent Static And Dynamic Behavior Of Circular Micro-Plates Subjected To Capillary Force

Simon Nessim Henein, Mohammad Hussein Kahrobaiyan, Ilan Vardi

The size-dependent static deflection, pull-in instability and resonant frequency of a circular microplate under capillary force have been studied using modified couple stress elasticity theory. SiZe-dependency is a phenomenon in which the normalized quanti ...

Amer Soc Mechanical Engineers2016

Resonance in swirling wakes and sloshing waves : non-normal and sublinear effects

Francesco Viola

Similarly to mechanical structures, stable flows can exhibit resonance when perturbed by an impulsive or harmonic forcing. Swirling wakes and sloshing waves belong to this kind of flows and manifest large energy response when excited close to their natural ...

EPFL2016

Human audiometric thresholds do not predict specific cellular damage in the inner ear

Demetri Psaltis

Introduction: As otology enters the field of gene therapy and human studies commence, the question arises whether audiograms - the current gold standard for the evaluation of hearing function - can consistently predict cellular damage within the human inne ...

Elsevier2016

Low frequency terahertz-induced demagnetization in ferromagnetic nickel

Mostafa Shalaby, Christoph Peter Hauri

A laser stimulus at terahertz (THz) frequency is expected to offer superior control over magnetization dynamics compared to an optical pulse, where ultrafast demagnetization is mediated by heat deposition. As a THz field cycle occurs on a timescale similar ...

Amer Inst Physics2016

What’s the Frequency, Kenneth?: Sublinear Fourier Sampling Off the Grid

Volkan Cevher, Yen-Huan Li

We design a sublinear Fourier sampling algorithm for a case of sparse off-grid frequency recovery. These are signals with the form f(t)=∑kj=1ajeiωjt+ν^ , t∈Z ; i.e., exponential polynomials with a noise term. The frequencies {ω j } satisfy ω j ∈ [η,2π − η ...

Springer Verlag2015

Tailoring single-cycle electromagnetic pulses in the 2–9 THz frequency range using DAST/SiO_2 multilayer structures pumped at Ti:sapphire wavelength

Jean-Pierre Wolf, Luigi Bonacina, Christoph Peter Hauri

We present a numerical parametric study of single-cycle electromagnetic pulse generation in a DAST/SiO2 multilayer structure via collinear optical rectification of 800 nm femtosecond laser pulses. It is shown that modifications of the thicknesses of the DA ...

Optical Society of America2014

New Cadanav methodology for quantitative rock fall hazard assessment and zoning at the local scale

Vincent Labiouse, Jacopo Maria Abbruzzese

Rock fall hazard zoning is a challenging yet necessary task to be accomplished for planning an appropriate land use in mountainous areas. Methodologies currently adopted for elaborating zoning maps do not provide satisfactory results though, due to uncerta ...

Springer Verlag2014

Implementation of a binaural localization algorithm in hearing aids: Specifications and achievable solutions

Hervé Lissek, Patrick Marmaroli, Gilles André Courtois

This article introduces the constraints and issues related to the implementation of a binaural localization algorithm on a pair of hearing aids. The algorithm should improve the rendering of the spatial information available in the audio signals, which are ...

2014

Multiphysics finite element model of a frequency-amplifying piezoelectric energy harvester with impact coupling for low-frequency vibrations

Nico de Rooij, Robert Andrew Lockhart, Danick Briand, Pattanaphong Janphuang, Andres Felipe Vasquez Quintero

This paper presents experimentally-verified multiphysics finite element model of a wideband vibration energy harvester with impact coupling, which operates on the principle of frequency up-conversion: under low-frequency harmonic base excitation a cantilev ...

Iop Publishing Ltd2013

A speckle-based CMOS sensor array for arbitrary surface movement detection

Steve Tanner, Pierre-André Farine, Chao Wang

The paper presents a CMOS sensor array for the detection of speckle movements, for applications requiring accurate movement tracking of arbitrary surfaces. The array is made of eight sensors incorporating each a spatial comb filter with a pitch of 2.8μm so ...

SPIE Society2011

Polar lattice vibrations and phase transition dynamics in Pb(Zr1-xTix)O-3

Dragan Damjanovic, Li Jin

Infrared (IR) reflectivity spectra of nominally pure Pb(Zr1-xTix)O-3 ceramics with different Ti/Zr concentration (x = 0.42-0.58) were measured and evaluated, along with the time-domain terahertz transmittance spectra in the temperature range 10 K-900 K. Th ...

2011

An Integrated Probe for Electromagnetic NDT Inspection

Pavel Kejik

Electromagnetic techniques present definite advantages for Non Destructive Testing such as no need for surface couplant, potential for miniaturization, and fast scanning rates. They suffer, however, from a lack of reliability when crack sizing capabilities ...

2010

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