Publications associées à Réflexion (physique)

The Advection Boundary Law in presence of mean-flow and spinning modes

In the attempt to reduce fuel consumption, a new generation of Ultra-High-By-Pass-Ratio (UHBR) turbofans have been introduced in the aeronautic industry which are structurally noisier especially at lower frequencies, because of their larger diameter, lower ...

SPIE2024

Electromagnetic time reversal for online partial discharge location in power cables: Influence of interfering reflections from grid components

Farhad Rachidi-Haeri, Marcos Rubinstein

In online single-sided partial discharge (PD) location, the measured PD reflection patterns are affected by the characteristics of all the components of the associated power network. This paper analyses the performance of a PD location method based on elec ...

2024

Plasmonic Nanostructures for Photocatalysis: Material, Photonic and Electronic Effects

Fateme Kiani Shahvandi

Plasmonic photochemistry has a large potential to replace energy-intensive chemical processes with low-temperature, low-pressure light-driven chemical reactions. Plasmonic nanostructures have emerged as promising photocatalysts with exceptional and tunable ...

EPFL2024

Modeling reflection by structured building-integrated photovoltaics

Stephen William Wasilewski

Evaluating the reflection of solar radiation by Building Integrated Photovoltaics (BIPV) with structured front-glass is challenging for two reasons. First, the resulting irregular scattering of light cannot be accounted for by simple reflection models. Sec ...

2023

Dielectric Elastomer Actuator-Based Valveless Impedance-Driven Pumping for Meso- and Macroscale Applications

Yves Perriard, Yoan René Cyrille Civet, Thomas Guillaume Martinez, Francesco Clavica, Armando Matthieu Walter, Amine Benouhiba, Silje Ekroll Jahren

Impedance pumps are simple designs that allow the generation or amplification of flow. They are fluid-filled systems based on flexible tubing connected to tubing with different impedances. A periodic off-center compression of the flexible tubing causes the ...

2023

Beam radiation penetration in particle b e ds for heat transfer modeling of a centrifugal solar particle receiver

Evan Fair Johnson, Serdar Hiçdurmaz

This article describes a study of beam radiation striking particle beds of randomly packed, spherical par-ticles. The current study is focused on concentrating solar power receivers which use solid particles as a heat transfer medium, but results are appli ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Broadband Air-Coupled Ultrasound Emitter and Receiver Enable Simultaneous Measurement of Thickness and Speed of Sound in Solids

Janez Rus

Air-coupled ultrasound sensors have advantages over contact ultrasound sensors when a sample should not become contaminated or influenced by the couplant or the measurement has to be a fast and automated inline process. Thereby, air-coupled transducers mus ...

MDPI2023

Quantification of the Phenomena Affecting Reflective Arterial Photoplethysmography

Nikolaos Stergiopoulos, Georgios Rovas, Vasiliki Bikia

Photoplethysmography (PPG) is a widely emerging method to assess vascular health in humans. The origins of the signal of reflective PPG on peripheral arteries have not been thoroughly investigated. We aimed to identify and quantify the optical and biomecha ...

MDPI2023

Observation of non-reciprocal harmonic conversion in real sounds

Romain Christophe Rémy Fleury, Hervé Lissek, Xinxin Guo

Reciprocity guarantees that in most media, sound transmission is symmetric between two points of space when the location of the source and receiver are interchanged. This fundamental law can be broken in non-linear media, often at the cost of detrimental i ...

2023

Method for operating a frequency agile tunable self-injection locking laser system and self-injection locking laser system

Tobias Kippenberg, Anat Siddharth, Grigorii Likhachev

The invention relates to a Method for operating a frequency agile tunable self-injection locking laser system being formed by a laser device coupled to at least one optical resonator, wherein a diode current of a laser diode of the laser device is controll ...

2023

Spin wave dispersion of ultra-low damping hematite ( α−Fe2O3 ) at GHz frequencies

Dirk Grundler, Mohammad Hamdi, Ferdinand Rémy Hynek Posva

Low magnetic damping and high group velocity of spin waves (SWs) or magnons are two crucial parameters for functional magnonic devices. Magnonics research on signal processing and wave-based computation at GHz frequencies focused on the artificial ferrimag ...

2023

Spin wave dispersion of ultra-low damping hematite (α-Fe2O3) at GHz frequencies

Dirk Grundler, Mohammad Hamdi, Ferdinand Rémy Hynek Posva

Raw data associated to the manuscript ‘’Spin wave dispersion of ultra-low damping hematite (α-Fe2O3) at GHz frequencies‘’, Physical Review Materials 7, 054407(2023); doi: 10.1103/PhysRevMaterials.7.054407 Information about file fo ...

Zenodo2023

Lippmann Photography: A Signal Processing Perspective

Martin Vetterli, Arnaud Latty, Adam James Scholefield, Gilles Baechler, Michalina Wanda Pacholska

Lippmann (or interferential) photography is the first and only analog photography method that can capture the full color spectrum of a scene in a single take. This technique, invented more than a hundred years ago, records the colors by creating interferen ...

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

Enhanced Signal-Associated Noise in a φ-OTDR System

Luc Thévenaz, Malak Mohamed Hossameldeen Omar Mohamed Galal, Suneetha Sebastian

Owing to their high sensitivity with respect to external measurands, Rayleigh-based distributed optical fiber sensors (DOFS) find their way into applications in many industrial and academic sectors. To further transcend the limit of these sensors in terms ...

2022

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

Reciprocal Metasurfaces for On-axis Reflective Optical Computing

Romain Christophe Rémy Fleury, Karim Achouri, Ali Momeni

Analog computing has emerged as a promising candidate for real-time and parallel continuous data processing. This paper presents a reciprocal way for realizing asymmetric optical transfer functions (OTFs) in the reflection side of the on-axis processing ch ...

2021

Sensing of Surface and Bulk Refractive Index Using Magnetophotonic Crystal with Hybrid Magneto-Optical Response

Serguei Sekatski

We propose an all-dielectric magneto-photonic crystal with a hybrid magneto-optical response that allows for the simultaneous measurements of the surface and bulk refractive index of the analyzed substance. The approach is based on two different spectral f ...

2021

Modeling specular transmission of complex fenestration systems with data-driven BSDFs

Jan Wienold

A Bidirectional Scattering Distribution Function (BSDF) describes how light from each incident direction is scattered (reflected and transmitted) by a simple or composite surface, such as a window shade. Compact, tabular BSDFs may be derived via interpolat ...

2021

Electrical transport properties of Ru1-xTixO2 films deposited by magnetron sputtering technique

Rosendo Sanjines, Silviu Cosmin Sandu

The optical and electrical properties of Ru1-xTixO2 (0

PERGAMON-ELSEVIER SCIENCE LTD2021