Critical Components Selection for a Prognostics and Health Management System Design: an Application to an Overhead Contact System

In recent years, improving quality of rail services by increasing availability, saving energy, and cutting the costs of infrastructure and rolling stock maintenance has become a central concern in the railway industry. Furthermore, considerable research efforts have been devoted to develop monitoring and health management solutions for the rail transportation systems. Streaming data from trains, infrastructure and signaling systems became a key subject for an implementation of a predictive maintenance. Prognostics and Health Management (PHM) is an approach that aims to support a predictive maintenance program. Basically, the first step to develop a PHM system is to identify critical components. This paper emphasizes on the critical components selection step. It presents a methodology to identify the critical components for the design of a PHM solution. The proposed methodology is based on objectives definition for PHM and it is applied to an Overhead Contact System (OCS

Development of a prognostics and health management system for the railway infrastructure – Review and methodology

The Prognostics and Health Management (PHM) can be considered as a key process to deploy a predictive maintenance program. Since its inception as an engineering discipline, a lot of diagnostics and prognostics algorithms were developed and furthermore methodologies for health management and PHM development established. These solutions were applied in a lot of industrial cases aiming a maintenance transformation. In the Aerospace and Military systems, for example, the PHM has been applied more than 20 years with systems and components applications. During this last decade, the railway industry focused on maintenance issues and expressed a special interest on the PHM systems. The maintenance of the railway infrastructure requires considerable resources and an important budget. Many of the developed algorithms and methodologies can be imported to the Rail Transport systems. However, a methodology to develop a PHM system for a railway infrastructure must be established. This paper provides an overview on the key steps to design a PHM system regarding to the specific characteristics of the railway infrastructure. In addition, tools and procedures for each level of the PHM process are reviewed, as well as a summary of the existing monitoring, health assessment and decision solutions for the railway infrastructure

Prognostics and health management for an overhead contact line system - A review

The railway industry in European countries is standing a significant competition from other modes of transportation, particularly in the field of freight transport. In this competitive context, railway stakeholders need to modernize their products and develop innovative solutions to manage their asset and reduce operational expenditures. As a result, activities such as condition-based and predictive maintenance became a major concern. Under those circumstances, there is a pressing need to implement prognostics and health management (PHM) solutions such as remote monitoring, fault diagnostics techniques, and prognostics technologies. Many studies in the PHM area for railway applications are focused on infrastructure systems such as railway track or turnouts. However, one of the key systems to ensure an efficient operability of the infrastructure is the overhead contact line (OCL). A defect or a failure of an OCL component may cause considerable delays, lead to important financial losses, or affect passengers safety. In addition maintaining this kind of geographically distributed systems is costly and difficult to forecast. This article reviews the state of practice and the state of the art of PHM for overhead contact line system. Key sensors, monitoring parameters, state detection algorithms, diagnostics approaches and prognostics models are reviewed. Also, research challenges and technical needs are highlighted

WEB 2.0 : 15 ans déjà et après ? : 7 pistes pour réenchanter Internet !

International audienceEn 15 ans, le Web 2.0 a radicalement transformé notre façon de travailler, de consommer, de vendre, de communiquer… Les technologies (mobile et tablette, 3G ou 4G, médias sociaux, big data, IA, etc.) ont bouleversé nos sphères de vie et notre rapport aux individus, à l’information, aux objets… 57 pionniers vous proposent d’explorer rétrospectivement les conséquences du digital sur notre société (économie, politique, juridique, culturel…). Le but : imaginer 7 pistes de réenchantement pour un futur numérique plus sain et plus responsable face à la domination des géants d’Internet, GAFA et BATX.La voix de 57 pionniers : Farid Arab . Thierry de Baillon . Christine Balagué . Éric Barbry . Beer Bergman . Olivier Berlingué . Nicolas Bermond . Fanny Berrebi . Michelle Blanc . Jérôme Bondu . Fadhila Brahimi . Frédéric Canevet . Dominique Cardon . Nicolas Celic . Cyrille Chaudoit . Jean-Pierre Corniou . Céline Crespin . André Dan . Yannis Delmas-Rigoutsos . Damien Douani . Antoine Dubuquoy . Jean-Philippe Encausse . Fabrice Epelboin . Olivier Ezratty . Isabelle Falque-Pierrotin . David Fayon . Mathieu Flaig . Cyrille Frank . Yann Gourvennec . David Guillocheau . Claudie Haigneré (Préface) . Olivier Iteanu . Henri Kaufman (Postface) . François Laurent . Yann Leroux . Éric Maillard . Vérone Mankou . Émilie Marquois . Grégory Maubon . Pierre Mawas . Pierre Métivier . Jean-Claude Morand . Ahmed Mehdi Omarouayache . Anthony Poncier . Grégory Pouy . PPC . Benoît Raphaël . Cyril Rimbaud . Vincent Rostaing . Jean-François Ruiz . Éric Seulliet . Serge Soudoplatoff . Virginie Spies . Yaëlle Teicher Stein . Pierre Tran . Pierre Vallet . Henri Verdier

Effect of chemoprevention by low-dose aspirin of new or recurrent colorectal adenomas in patients with Lynch syndrome (AAS-Lynch): study protocol for a multicenter, double-blind, placebo-controlled randomized controlled trial

Abstract Lynch syndrome (LS) is the most common cause of inherited colorectal cancer (CRC) and confers a high lifetime risk of CRC estimated to be up to 60%. Colonoscopy is recommended every 2 years in LS patients above the 20–25-year-old age bracket, and every year when colonic neoplasia has been detected. Efficient chemoprevention has the potential to represent a cost-effective intervention in these high-risk patients and could allow a delay in colonoscopy surveillance. Several epidemiological studies have shown that regular use of low dose aspirin is associated with a 20 to 30% reduction in the risk of sporadic colonic adenomas and colorectal cancer regardless of family risk. However, in recent large randomized trials in specific populations, aspirin use showed no protection for colorectal cancer. A prospective randomized CAPP-2 trial evaluated the effect of aspirin use in LS patients. The primary analysis of this trial showed no significant decrease in CRC in LS patients under daily aspirin. However, a preplanned secondary analysis after an extended follow-up showed a significant reduced risk of CRC in the aspirin group in the per-protocol analysis. The real effect and clinical benefit of aspirin are still to be consolidated in this population. The AAS-Lynch trial—a prospective, multicentric, double-blind, placebo-controlled, randomized clinical trial—was designed to investigate if daily aspirin therapy, at a dose of 100 or 300 mg, would decrease the occurrence or recurrence of colorectal adenomas in patients under 75 years of age, compared with placebo. Trial registration ClinicalTrials.gov NCT02813824 . Registered on 27 June 2016. The trial was prospectively registered

Low incidence of SARS-CoV-2, risk factors of mortality and the course of illness in the French national cohort of dialysis patients

International audienceThe aim of this study was to estimate the incidence of COVID-19 disease in the French national population of dialysis patients, their course of illness and to identify the risk factors associated with mortality. Our study included all patients on dialysis recorded in the French REIN Registry in April 2020. Clinical characteristics at last follow-up and the evolution of COVID-19 illness severity over time were recorded for diagnosed cases (either suspicious clinical symptoms, characteristic signs on the chest scan or a positive reverse transcription polymerase chain reaction) for SARS-CoV-2. A total of 1,621 infected patients were reported on the REIN registry from March 16th, 2020 to May 4th, 2020. Of these, 344 died. The prevalence of COVID-19 patients varied from less than 1% to 10% between regions. The probability of being a case was higher in males, patients with diabetes, those in need of assistance for transfer or treated at a self-care unit. Dialysis at home was associated with a lower probability of being infected as was being a smoker, a former smoker, having an active malignancy, or peripheral vascular disease. Mortality in diagnosed cases (21%) was associated with the same causes as in the general population. Higher age, hypoalbuminemia and the presence of an ischemic heart disease were statistically independently associated with a higher risk of death. Being treated at a selfcare unit was associated with a lower risk. Thus, our study showed a relatively low frequency of COVID-19 among dialysis patients contrary to what might have been assumed