Search results for "flux [cosmic radiation]"
showing 10 items of 153 documents
Long range rapidity correlations and the ridge in A+A collisions
2009
We discuss results for n-gluon correlations that form the basis of the Glasma flux tube picture of early times in heavy ion collisions. Our formalism is valid to all orders in perturbation theory at leading logarithmic accuracy in x and includes both QCD bremsstrahlung and the many body screening and recombination effects that are important at large parton densities. Long range rapidity correlations, as seen in the near-side ridge in heavy ion collisions, are a chronometer of these early time strong color field dynamics. They also contain information on how radial flow develops in heavy ion collisions.
Estimating radiant fields in flat heterogeneous photoreactors by the six-flux model
2006
Heterogeneous photoreactor modeling is a task complicated by the integro-differential nature of the Radiation Transfer Equation (RTE) when scattering phenomena are important. In the present work, a novel “Six Flux Model” (SFM) is proposed, which may be regarded as a step forward with respect to the previously proposed “Two Flux Model” (TFM). In order to validate the newly proposed model, Monte Carlo simulations of an indefinite plane-slab photoreactor have been performed. As no simplifying assumptions are involved in this case, the information obtained may be regarded as “pseudo-experimental,” and therefore compared with the predictions of both TFM and SFM models. Results show that the nove…
Gastro-oesophageal reflux and "epileptic" attacks: casually associated or related? Efficiency of antireflux surgery. A case report
2009
Although a possible link between gastro-oesophageal reflux disease (GORD) and obstructive sleeping apnoea has already been reported in the literature, there has never been any suggestion of an association with epilepsy, and epileptic attacks have not so far been included among gastro-oesophageal reflux disease symptoms. We report the case of a patient with gastro-oesophageal reflux disease associated with a sliding hiatus hernia, a short oesophagus and oesophagitis, who for the last ten years had not only presented the typical symptoms of gastrooesophageal reflux, but also symptoms of obstructive sleep apnoea and epileptic-like attacks occurring occasionally and only during sleep. Partial p…
A 3D totally absorbable synthetic mesh in antireflux surgery: Gore Bio-A tissue reinforcement for hiatal hernia repairing
2015
Introduction Hiatal hernia, defined as “transitory or stable dislocation of a part of the stomach in mediastinum through the diaphragmatic crura delimiting esophageal hiatus”. Its appearance presupposes anatomic anomalies or weakening of structures and mechanisms able to maintain esophago-gastric junction and stomach in the abdominal cavity [1]. Classically hiatal hernia was classified in four types using Hill’s classification: Type 1 hiatal hernia is associated with GERD in 50-90% of cases, in facts its presence gradually compromises esophago-gastric junction’s continence favouriting the backwater of acid secretion and its reflux in contact with esophageal mucosa during transient relaxatio…
Chemical characterisation of the gases released at Gyali Island, Dodecanese, Greece and preliminary estimation of the CO2 output
2021
Greece belongs to the most geodynamically active regions of the world and as such, it has to be considered an area of intense geogenic degassing. In terms of carbon, the territory is characterized by the high hydrothermal and volcanic activity of the South Aegean Active Volcanic Arc (SAAVA), and by widespread geological seeps of buried carbon dioxide and methane. In the present work, we investigate the island of Gyali located in the volcanic system Kos-Gyali-Nisyros. Nine gas samples have been collected on the island of Gyali in areas found both on land, in a small lake (∼2000 m2) along its beach, and in the sea close to the shore at shallow depths (<20 m). Results show that CO2 is the p…
On implementation of the Gibbs sampler for estimating the accuracy of multiple diagnostic tests
2010
Implementation of the Gibbs sampler for estimating the accuracy of multiple binary diagnostic tests in one population has been investigated. This method, proposed by Joseph, Gyorkos and Coupal, makes use of a Bayesian approach and is used in the absence of a gold standard to estimate the prevalence, the sensitivity and specificity of medical diagnostic tests. The expressions that allow this method to be implemented for an arbitrary number of tests are given. By using the convergence diagnostics procedure of Raftery and Lewis, the relation between the number of iterations of Gibbs sampling and the precision of the estimated quantiles of the posterior distributions is derived. An example conc…
3D MHD MODELING of TWISTED CORONAL LOOPS
2016
We perform MHD modeling of a single bright coronal loop to include the interaction with a non-uniform magnetic field. The field is stressed by random footpoint rotation in the central region and its energy is dissipated into heating by growing currents through anomalous magnetic diffusivity that switches on in the corona above a current density threshold. We model an entire single magnetic flux tube, in the solar atmosphere extending from the high-beta chromosphere to the low-beta corona through the steep transition region. The magnetic field expands from the chromosphere to the corona. The maximum resolution is ~30 km. We obtain an overall evolution typical of loop models and realistic loo…
Magnetic hysteresis in the microwave surface resistance of Nb samples in the critical state
2006
We discuss the hysteretic behavior of the field-induced variations of the microwave surface resistance in superconductors in the critical state. Measurements have been performed in a bulk sample of Nb and a powdered one at different values of the temperature. We discuss a model, based on the Coffey and Clem theory, in which we take into account the flux distribution inside the sample, due to the critical state. The experimental results are justified quantitatively in the framework of our model. We show that by fitting the experimental data it is possible to determine the value of the critical current density and its field dependence.
Design of a transverse flux machine for power generation from seawaves
2014
In this paper, we present a transverse flux linear generator. We investigate the possibility to use this generator to extract energy from seawaves. We propose an optimization procedure that allows us to obtain an optimized design of the generator. The optimized design of the converter shows a power generation capability index much higher than other renewable systems.
Visualisation et analyse spatio-temporelle de trajectoires maritimes
2016
Bedrock of globalization, maritime transport is paradoxically the poor sibling of network analysis and flow mapping. But the unprecedented use of archival data allows us to consider a long-term analysis