Publications associées à Non-line-of-sight propagation

A Gradient-Gated SPAD Array for Non-Line-of-Sight Imaging

Edoardo Charbon, Pouyan Keshavarzian, Jiuxuan Zhao, Francesco Gramuglia, Myung Jae Lee

Time-resolved non-line-of-sight (NLOS) imaging based on single-photon avalanche diode (SPAD) detectors have demonstrated impressive results in recent years. To acquire adequate number of indirect photons from a hidden scene in the presence of overwhelming ...

Ieee-Inst Electrical Electronics Engineers Inc2024

Partial discharge localization in power transformers using acoustic time reversal

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Hamidreza Karami, Florent Quentin Aviolat

The localization of partial discharges (PD) is important to monitor the conditioning of high voltage insulator materials. One of the key components in power grids is the high power transformer. Localization of PDs in these pieces of equipment can increase ...

Elsevier2022

A Correlation-Based Electromagnetic Time Reversal Technique to Locate Indoor Transient Radiation Sources

Farhad Rachidi-Haeri, Marcos Rubinstein, Zhaoyang Wang, Qi Li

To overcome the multipath interference in locating transient electromagnetic (EM) radiation sources in an indoor environment, we propose a criterion that calculates the correlation between back-propagated signals from observation points, to be used in EM t ...

Institute of Electrical and Electronics Engineers2021

An experimental validation of partial discharge localization using electromagnetic time reversal

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

The localization of partial discharge (PD) sources is of importance for the monitoring and maintenance of power transformers. Time difference of arrival (TDoA) based methods are widely adopted in the literature for the localization of PDs. Recently, time r ...

Nature Research2021

Nature of Crack Path Instabilities in Thin Sheets Cut by Blunt Objects

Iryna Sivak

Cutting a brittle thin sheet with a blunt object leaves an oscillating crack that seemingly violates the principle of local symmetry for fracture. We experimentally find that at a critical value of a well chosen control parameter the straight propagation i ...

AMER PHYSICAL SOC2020

Analysis of a bipolar upward lightning flash based on simultaneous records of currents and 380-km distant electric fields

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Amirhossein Mostajabi, Wolfgang Schulz, Davide Pavanello, Dongshuai Li

In this paper, we present and discuss simultaneous records of current and wideband electric field waveforms at 380 km distance from the strike point associated with an upward bipolar flash initiated from the Säntis Tower. The flash contains 23 negative str ...

Elsevier2019

Modeling of parasitic oscillations in smooth-wall circular symmetric dielectric-loaded gyrotron beam ducts

Stefano Alberti, Jean-Philippe Hogge, Jérémy Genoud

The self-consistent simulation of the electron beam interaction was performed in the presence of a lossy dielectric layer in the smooth-wall beam duct of a gyrotron oscillator. For this purpose, the linear and spectral code TWANGlinspec was extended. In th ...

AMER INST PHYSICS2019

Constant-pressure sound waves in non-Hermitian disordered media

Romain Christophe Rémy Fleury, Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Stefan Rotter

When waves impinge on a disordered material they are back-scattered and form a highly complex interference pattern. Suppressing any such distortions of a wave’s free propagation is a challenging task with many applications in a number of different discipli ...

2018

Photoinitiator-free Laser Fabrication of Ultra-compact, Low-loss Waveguides in Polydimethylsiloxane

Demetri Psaltis, Christophe Moser, Ye Pu, Giulia Panusa, Jieping Wang

Owing to its excellent elasticity, wide spectral range of transparency, and outstanding chemical and thermal stability, polydimethylsiloxane (PDMS) is an elastomer of great technological importance, being widely used in the fabrication of microfluidic and ...

SPIE-INT SOC OPTICAL ENGINEERING2018

Learning Tomography Assessed Using Mie Theory

Michaël Unser, Demetri Psaltis, Joowon Lim

In optical diffraction tomography, the multiply scattered field is a nonlinear function of the refractive index (RI) of the object. The Rytov method relies on a single-scattering propagation model and is commonly used to reconstruct images. Recently, a rec ...

American Physical Society (APS)2018