Search results for "Image"

Shear Effects in Elastic Nanobeams

2020

Small-scale, shear deformable nanobeams, subjected to quasi-static loads, are analyzed by a nonlocal (integral) elasticity model with the main goal to evaluate the influence of shear deformation on size effects. To this aim a warping parametric model is considered in order to obtain a continuous family of shear deformable beam models which span from the Euler-Bernoulli to the Thimoshenko beam model, passing from the Reddy model. The strain difference based nonlocal elasticity theory is applied under the hypotheses of small displacements and isotropic material. The results, obtained by analysing a cantilever nonlocal nanobeam, indicate that shear deformation has a considerable influence upon…

ATLAS beam test results

1996

Many different configurations of electronics and-semiconductor strip detectors were studied in 1995 using the ATLAS tracking detector test area at the H8 beam-line of the CERN SPS. A significant fraction of these investigations are presented elsewhere in this volume and this paper will concentrate on the results with silicon strip detectors read out with electronics preserving the pulse height information. Data has been collected with the ADAM, APV5 and FElix read-out chips on a number of different detectors. The first results are presented for read out with LHC electronics of detectors to the ATLAS-A specification of 112.5 mu m pitch, employing n-strips in n-type silicon, capacitive coupli…

Hierarquia e autoridade capetíngia no século XI: imagem e texto

2011

Em um caderno de 6 fólios, um deles hoje desaparecido, de pequeno formato (170 x 250 mm), em torno de 1076-1077, os cônegos regulares da abadia de Saint-Martin-des-Champs compuseram uma obra, conservada atualmente na British Library (Add 11662, f. 4r-8r), que reúne em torno de três atos diplomáticos, uma narrativa em versos e em imagens. Conhecida como " chronique versifiée " ou " livre des privilèges ", e editado em 1912 por Jean Depoin, o manuscrito foi copiado com a adição de três outros documentos e uma nova interpretação das imagens em meados do século XIII, obra que se encontra hoje em Paris (BnF, nouv. acq. lat. 1359). Nenhum estudo analisou ainda atentadamente as imagens contidas no…

ANALISI E SVILUPPO DI UN SETUP SPERIMENTALE PER LA DETERMINAZIONE DELLA TENACITÀ A FRATTURA A MODO II NEI MATERIALI COMPOSITI E IBRIDI

Il presente lavoro di Tesi si propone a compimento del percorso previsto dal Ciclo XXVI del corso di Dottorato di Ricerca in Ingegneria Civile e Ambientale – Indirizzo Materiali – seguito durante il triennio Gennaio 2013- Dicembre 2015 presso l’Università degli Studi di Palermo. L’elaborato si sviluppa in due principali sezioni. Dopo un’introduzione all’argomento affrontato, nella prima parte del lavoro, viene analizzato, sia sperimentalmente che numericamente, un setup tipicamente utilizzato nell’industria aeronautica per la caratterizzazione delle delaminazione a MODO II nei materiali compositi (Transverse Crack Tensile test – TCT-test). A partire dai risultati ottenuti dalle analisi prel…

GridNet with Automatic Shape Prior Registration for Automatic MRI Cardiac Segmentation

2018

In this paper, we propose a fully automatic MRI cardiac segmentation method based on a novel deep convolutional neural network (CNN) designed for the 2017 ACDC MICCAI challenge. The novelty of our network comes with its embedded shape prior and its loss function tailored to the cardiac anatomy. Our model includes a cardiac center-of-mass regression module which allows for an automatic shape prior registration. Also, since our method processes raw MR images without any manual preprocessing and/or image cropping, our CNN learns both high-level features (useful to distinguish the heart from other organs with a similar shape) and low-level features (useful to get accurate segmentation results).…

Pulse rate variability measurement with camera-based photoplethysmography

2021

Electrocardiogram (ECG) has been used by doctors and biomedical researchers to measure cardiac parameters such as Heart Rate (HR) and Heart Rate Variability (HRV). HR is a medical index for health monitoring and the HRV is a sign to reflect the activities of Autonomic Nervous System (ANS) and can be used for emotion recognition applications. Recently, remote photoplethysmography (rPPG) has evolved as a non-contact technique for measuring vital cardiac signs. Compared with ECG, this technique is non-invasive, low-cost, comfortable and possibly utilized in long-term monitoring. It has great potential in remote health assessment and emotion detection. However, the rPPG is a video-based method,…

Patients with acute chest pain, elevated troponin and normal coronary arteries, could be the Cardiovascular Magnetic Resonance advantageous?

2013

Modified electrocardiograph-triggered black-blood turbo spin-echo technique to improve T1-weighting in contrast-enhanced MRI of atherosclerotic carot…

2008

Purpose To assess the efficacy of a modified electrocardiograph (EKG)-triggered black-blood T1W (T1W) spin-echo sequence in improving contrast on post-gadolinium high-resolution carotid plaque imaging by implementing heart-rate–independent contrast preparation. Materials and Methods We used a standard EKG-triggered double inversion-recovery (DIR) turbo spin-echo (TSE) sequence modified with the addition of an extra saturation (90°) radio frequency (RF) pulse placed immediately after the DIR module, shortening the repetition time to a fixed value of 400 msec. A total of 10 patients with atherosclerotic disease were included in the study. Postinjection intraplaque contrast measurements were p…

Integrated non-invasive approach to atherosclerosis with cardiac CT and carotid ultrasound in patients with suspected coronary artery disease

2017

The aim of the study was to compare the atherosclerotic disease in the coronary and carotid arteries in patients who underwent non-invasive imaging for suspected stable coronary artery disease (CAD). 107 patients (64 men, age 59 ± 12) with atypical chest pain underwent cardiac CT (CCT) and carotid ultrasound (US) on the same day. Severity (obstructive or not-obstructive disease), location, shape, and composition of atherosclerotic plaques in the two districts were evaluated. Patients presented normal coronary arteries in 36 % (n = 38), not-obstructive CAD in 36 % (n = 39), and obstructive CAD in 28 % (n = 30), while had normal carotid arteries in 53 % (n = 57), not-obstructive disease in 44…

Going beyond histology. Synchrotron micro-computed tomography as a methodology for biological tissue characterization: from tissue morphology to indi…

2009

Current light microscopic methods such as serial sectioning, confocal microscopy or multiphoton microscopy are severely limited in their ability to analyse rather opaque biological structures in three dimensions, while electron optical methods offer either a good three-dimensional topographic visualization (scanning electron microscopy) or high-resolution imaging of very thin samples (transmission electron microscopy). However, sample preparation commonly results in a significant alteration and the destruction of the three-dimensional integrity of the specimen. Depending on the selected photon energy, the interaction between X-rays and biological matter provides semi-transparency of the spe…