Publications associées à Dental radiography

Characterization of a flexible a-Si:H detector for in vivo dosimetry in therapeutic x-ray beams

Sylvain Dunand, Nicolas Würsch, Luca Massimiliano Antognini, Jonathan Emanuel Thomet, Matthew James Large

BackgroundThe increasing use of complex and high dose-rate treatments in radiation therapy necessitates advanced detectors to provide accurate dosimetry. Rather than relying on pre-treatment quality assurance (QA) measurements alone, many countries are now ...

Wiley2024

Measurement and modelling of dynamic fluid saturation in carbon reinforcements

Véronique Michaud, Baris Çaglar, Helena Luisa Teixido Pedarros, Guillaume Clément Broggi

We propose a methodology to monitor the progressive saturation of a non-translucent unidirectional carbon fabric stack through its thickness by means of X-ray radiography and extract the dynamic saturation curves using image analysis. Four constant flow ra ...

2023

Effect of wettability and textile architecture on fluid displacement and pore formation during infiltration of carbon fibrous preforms

Véronique Michaud, Baris Çaglar, Helena Luisa Teixido Pedarros

We seek to address how air entrapment mechanisms during infiltration are influenced by the wetting characteristics of the fluid and the pore network formed by the reinforcement. To this end, we evaluated the behavior of two model fluids with different surf ...

Elsevier Sci Ltd2023

Liquid metal infiltration of silicon based alloys into porous carbonaceous materials. Part II: Experimental verification of modelling approaches by infiltration of Si-Zr alloy into idealized microchannels

Ludger Weber, Caroline Hain, Giovanni Bianchi, Alberto Ortona, Manoj Kondibhau Naikade

In this work, the mechanisms leading to the pore closure in reactive melt infiltration (RMI) of carbon by pure silicon and a near eutectic Si-8 at-pct Zr alloy at 1500 and 1700 degrees C under vacuum were studied. Various geometrical configurations of micr ...

ELSEVIER SCI LTD2022

Cross verified independent measurements of correlated bubble property distributions as part of the scale-up of a catalytic bubbling fluidized bed reactor

Philipp Fedor Riechmann

Methanation can be applied as part of a Power-to-Gas (PtG) concept to store renewable electricity. Using a catalytic bubbling fluidized bed (BFB) methanation reactor allows a flexible and economic operation. Properties of bubbles rising through the fluidiz ...

EPFL2022

Learning to sample in Cartesian MRI

Thomas Sanchez

Magnetic Resonance Imaging (MRI) is a non-invasive, non-ionizing imaging modality with unmatched soft tissue contrast. However, compared to imaging methods like X-ray radiography, MRI suffers from long scanning times, due to its inherently sequential acqui ...

EPFL2022

Medipix4, a high granularity four sides buttable pixel readout chip for high resolution spectroscopic X-ray imaging at rates compatible with medical CT scans

Viros Sriskaran

Medipix4 is the latest member in the Medipix/Timepix family of pixel detector chips aimed at high rate spectroscopic X-ray imaging using high-Z materials. The chip address the limitations of conventional hybrid pixel detectors for X-ray imaging. Its predec ...

EPFL2022

Ion temperature spectroscopic measurements in high rotation discharges by means of X-ray diagnostic at JET

Henri Weisen

Measurement of the X-ray spectra of the He-like Ni ions (Ni26+) and their dielectronic satellites (Ni25+, Ni24+, and Ni23+) plays a crucial role in determination of electronic and ion temperature of plasma in the JET device. Because n >= 3 satellites of Ni ...

2022

Single-projection reconstruction technique for positioning monodisperse spheres in 3D with a divergent x-ray beam

Edward Carlo Giorgio Andò

The measurement of the position of single-sized spheres in 3D from a single, divergent, radiographic projection is addressed in the present study with the development of a novel method. Generally speaking, the location of the shadow cast by a single sphere ...

2021

Three-Dimensional Cubic Barcodes

Martin Vetterli, Adam James Scholefield, Golnooshsadat Elhami

We consider three-dimensional cubic barcodes, consisting of smaller cubes, each built from one of two possible materials and carry one bit of information. To retrieve the information stored in the barcode, we measure a 2-D projection of the barcode using a ...

2022

Experimental analysis of suprathermal electrons generated by electron cyclotron waves in tokamak plasmas

Dahye Choi

This thesis focuses on the physics of suprathermal electrons generated by electron cyclotron (EC) waves in tokamak plasmas, which play an important role in the physics of current drive and energetic particle-driven instabilities. The suprathermal electron ...

EPFL2020

SciFi detector and associated method for real-time determination of profile and output factor for small fields in stereotactic radiotherapy

Guido Haefeli, Frédéric Blanc, Plamen Hristov Hopchev, Philippe Pittet

Purpose For determining small-field profile and output factor during stereotactic radiotherapy quality assurance (QA) procedures, we propose a novel system based on the scintillating fiber (SciFi) detector with output image acquisition and processing to al ...

WILEY2020

Predrilled locking compression plate is more accurate than tension band wiring in restoring articular geometry of the ulnar greater sigmoid notch after olecranon Chevron osteotomy

Alexandre Terrier, Patrick Goetti, Frédéric Vauclair

Introduction: The olecranon Chevron osteotomy (OCO) is commonly used to approach complex intraarticular fractures of the distal humerus. Predrilled tension band wiring (TBW) has historically been used to fix OCO. However, clinical outcomes are burdened by ...

ELSEVIER SCI LTD2020

Caries Detection with Near-Infrared Transillumination Using Deep Learning

Henry Markram, Felix Schürmann, Taylor Howard Newton, Francesco Casalegno

Dental caries is the most prevalent chronic condition worldwide. Early detection can significantly improve treatment outcomes and reduce the need for invasive procedures. Recently, near-infrared transillumination (TI) imaging has been shown to be effective ...

2019

Deep neural networks for plasma tomography with applications to JET and COMPASS

Olivier Sauter, Ambrogio Fasoli, Yiming Li, Basil Duval, Jonathan Graves, Duccio Testa, Patrick Blanchard, Henri Weisen, Federico Nespoli, Alessandro Pau, Federico Alberto Alfredo Felici, Dalziel Joseph Wilson, Hamish William Patten, Cristian Sommariva, Antoine Pierre Emmanuel Alexis Merle, Samuel Lanthaler, Haomin Sun, Michele Marin, Richard Pitts, Yann Camenen, Jan Horacek, Javier García Hernández, Marco Wischmeier, Nicola Vianello, Mikhail Maslov, Yao Zhou, Davide Galassi, Antonio José Pereira de Figueiredo, Emiliano Fable, Francesca Maria Poli, Daniele Brunetti, Anna Teplukhina, Alberto Mariani, Kenji Tanaka, Bernhard Sieglin, Otto Asunta, Gergely Papp, Leonardo Pigatto

Convolutional neural networks (CNNs) have found applications in many image processing tasks, such as feature extraction, image classification, and object recognition. It has also been shown that the inverse of CNNs, so-called deconvolutional neural network ...

2019

Probing Molecular Chirality by Orbital-Angular-Momentum-Carrying X-ray Pulses

Jérémy Raymond Jean Maurice Rouxel

A twisted X-ray beam with orbital angular momentum is employed in a theoretical study to probe molecular chirality. A nonlocal response description of the matter-field coupling is adopted to account for the field short wavelength and the structured spatial ...

AMER CHEMICAL SOC2019

Region Of Interest X-Ray Computed Tomography Via Corrected Back Projection

Michaël Unser, Michael Thompson McCann, Laura Vilaclara

We present a new method for region of interest (ROI) reconstruction from high-resolution, nontruncated data in parallel-ray X-ray computed tomography (CT). Many of the approaches to ROI CT reconstruction in the literature rely on a costly forward projectio ...

IEEE2018

High-Quality Parallel-Ray x-Ray CT Back Projection Using Optimized Interpolation

Michaël Unser, Michael Thompson McCann

We propose a new, cost-efficient method for computing back projections in parallel-ray X-ray CT. Forward and back projections are the basis of almost all X-ray CT reconstruction methods, but computing these accurately is costly. In the special case of para ...

2017

Implant-based three-dimensional superimposition of the growing mandible in a rabbit model

The reliable assessment of craniofacial morphological changes during growth requires invariant regions for image registration. As these regions have not yet been identified in three dimensions, intra-osseous implants are required as fiducial markers for th ...

Oxford Univ Press2016

Energy-selective neutron imaging for materials science

Steven Luc X Peetermans

Common neutron imaging techniques study the attenuation of a neutron beam penetrating a sample of interest. The recorded radiograph shows a contrast depending on traversed material and its thickness. Tomography allows separating both and obtaining 3D spati ...

EPFL2015