Uncertainty Assessment for PA Models

A mathematical model comprises input variables, output variables and equations relating these quantities. The input variables may vary within some ranges, reflecting either our incomplete knowledge about them (epistemic uncertainty) or their intrinsic variability (aleatory uncertainty). Moreover when solving numerically the equations of the model, numerical errors are also arising. The effects of such errors and variations of the inputs have to be quantified in order to asses the model¿s range of validity. The goal of uncertainty analysis is to asses the effects of parameter uncertainties on the uncertainties in computed results. The purpose of this report is to give an overview of the most useful probabilistic and statistic techniques and methods to characterize uncertainty propagation. Some examples of application of these techniques for PA applied to radioactive waste disposal are given.JRC.F.4-Safety of future nuclear reactor

Review of Sensitivity Analysis Methods and Experience for Geological Disposal of Radioactive waste and Spent Nuclear Fuel

This reports gives an overview of sensitivity methods (screening, global and response surface based) that are suitable for safety analysis of a repository for radioactive waste or spent nuclear fuel. The theorerical background of the methods, their limitations and suitability for different analyses are discussed and illustrated by examples.JRC.F.7-Energy systems evaluatio

Les leviers de la création de valeur partagée en contexte PME : étude exploratoire dans la région Rhône-Alpes

http://www.strategie-aims.com/events/conferences/24-xxiiieme-conference-de-l-aims/communications/3106-les-leviers-de-la-creation-de-valeur-partagee-en-contexte-pme-etude-exploratoire-dans-la-region-rhone-alpes/downloadInternational audienceLa notion de création de valeur partagée (Porter, Kramer, 2011) invite les entreprises à replacer les démarches de responsabilité sociétale (RSE) a u cœur de leur stratégie, tout en recherchant la compétitivité. Parallèlement, les travaux académiques sur la RSE dans l'univers des PME demeurent marginaux en dépit d'un regain d'intérêt récent (Spence, Perrini, 2009). Ce papier exploratoire propose d'interroger la pertinence de la création de valeur partagée au travers de ses trois leviers : (1) l'intégration à un réseau territorialisé; (2) la remise à plat des produits/services et marchés de l'entreprise et (3) la redéfinition de sa chaîne de valeur dans le contexte des PME. Une enquête par questionnaire a été réalisée dans la région Rhône-Alpes auprès de 488 PME. Les résultats des analyses statistiques montrent que la notion de création de valeur partagée telle que présentée par Porter et Kramer (2011) nécessite des aménagements de manière à mieux refléter les réalités des PME. De nature exploratoire, cette étude invite à approfondir les résultats notamment en termes de renforcement potentiel des différents leviers mobilisés par les PME au travers d'une analyse dynamique, par exemple

The cathodic evolution of hydrogen on nickel in artificial seawater

The hydrogen evolution reaction (HER) on Ni electrode in artificial seawater was investigated by steady-state polarisation curves and electrochemical impedance spectroscopy methods at the room temperature and at high temperatures (30–60oC). The electrochemical kinetics parameters of the HER – Tafel slope, charge transfer coefficient and exchange current density – were evaluated in accordance with the potential scan direction and temperature. The Tafel slopes are significantly higher than 120 mV/decade and they increase with the increasing of the solution temperature. The charge transfer coefficient is lower than 0.5 and it decreases with temperature. The exchange current density has a magnitude order of 10-5 A·cm-2 and its value is increasing with increasing solution temperature. The activation energy of the HER has a moderate value, that slowly decreases with the cathodic polarisation increase. The HER is controlled by the charge transfer step and by the mass transfer of the intermediate reaction product Hads on the electrode surface

Arterial vascularization of the colon; a guide to surgical resection

Background. Colorectal cancer is a commonly diagnosed neoplasia in men and women worldwide. This study aims to rigorously map the arterial distribution of the colon in order to assess the implications of vascular patterns in surgical resection. Methods. Cadaveric dissections were performed to explore the arterial distribution (including collateral blood flow) of the colon. The study used standard dissection tools and photographic documentation to detail the vascular architecture supporting the large intestine. Results. The dissection revealed important arterial branches and anastomoses in the area of the superior and inferior mesenteric arteries, which are able to ensure continuous local blood supply especially in cases of arterial ischemia. An important arterial anastomosis was identified between the right branch of the middle colic artery and the ascending branch of the right colic artery, as well as the specific distribution of the marginal artery of Drummond and Haller-Riolan anastomotic arch. Conclusions. The blood supply of the colon derived from both mesenteric arteries includes redundant arterial anastomoses, but which are critical in specific situations such as the approach and results of surgical resection. Understanding these vascular patterns and collateral pathways, as well as careful intraoperative surgical exploration, are essential for oncologic surgeons to ensure successful colic resections with minimal complications and morbidity

PFO-spectrum disorder: two different cerebrovascular diseases in patients with PFO as detected by AI brain imaging software

BackgroundPatent foramen ovale (PFO) is a prevalent cardiac remnant of fetal anatomy that may pose a risk factor for stroke in some patients, while others can present with asymptomatic white matter (WM) lesions. The current study aimed to test the hypothesis that patients with a PFO who have a history of stroke or transient ischemic attack, compared to those without such a history, have a different burden and distribution of cerebral WM hyperintensities. Additionally, we tested the association between PFO morphological characteristics and severity of shunt, and their impact on the occurrence of ischemic cerebral vascular events and on the burden of cerebral WM lesions.Patients and methodsRetrospective, case–control study that included patients with PFO confirmed by transesophageal echocardiography. Right-to-left shunt size was assessed using transcranial Doppler ultrasound. Cerebral MRIs were analyzed for all participants using the semi-automated Quantib NDTM software for the objective quantification of WM lesions. WM lesions volume was compared between patients with and without a history of stroke. Additionally, the anatomical characteristics of PFOs were assessed to explore their relation to stroke occurrence and WM lesions volume.ResultsOf the initial 264 patients diagnosed with PFO, 67 met the inclusion criteria and were included in the analysis. Of them, 62% had a history of PFO-related stroke/TIA. Overall burden of WM lesions, including stroke volume, was not significantly different (p = 0.103). However, after excluding stroke volume, WM lesions volume was significantly higher in patients without stroke (0.27 cm3, IQR 0.03–0.60) compared to those with stroke/TIA (0.08 cm3, IQR 0.02–0.18), p = 0.019. Patients with a history of PFO-related stroke/TIA had a tendency to larger PFO sizes by comparison to those without, in terms of length and height, and exhibited greater right-to-left shunt volumes.DiscussionWe suggest that PFO may be associated with the development of two distinct cerebrovascular conditions (stroke and “silent” WM lesions), each characterized by unique imaging patterns. Further studies are needed to identify better the “at-risk” PFOs and gain deeper insights into their clinical implications

General Pattern Recognition

International audienc