ARCHITECTURE TRANSPARENTE EN FIBRE MULTIMODE ET TECHNOLOGIE CWDM POUR UN RESEAU LOCAL DOMESTIQUE MULTIFORMAT

National audienceNous proposons une solution de réseau domestique optique, associant une architecture transparente basée sur la fibre multimode et la technologie CWDM. Des signaux de natures différentes et diverses topologies peuvent coexister sur cette infrastructure multiformat, ce qui lui confère une grande flexibilité et une forte évolutivité. Les problèmes, issus de l'association de la technologie CWDM avec des composants passifs multimodes, sont discutés

Towards a multiservice & multiformat optical home area networks

International audienceWe propose mid and long term visions of optical Home Area Networks. The challenge is not only to increase the network capacity, but also to take into account the heterogeneity of the signals to be conveyed: Ethernet, RF TV and radio signals for wireless-end-connectivity. Two solutions are described: a mid term solution, based on an active star and centered on a multiformat switch, and a long term solution based on a fully transparent infrastructure, associated with optical wavelength multiplexing. These solutions and the corresponding realized setups will be described and compared in terms of performances, flexibility and robustness to future evolutions

Optical home network based on an NxN multimode fiber architecture and CWDM technology

International audienceWith this optical home network solution associating an NxN multimode architecture and CWDM technology, various applications and network topologies are supported by a unique multiformat infrastructure. Issues related to the use of MMF are discussed

CORROSION MECHANISMS OF ZIRCONIA/CARBON BASED REFRACTORY MATERIALS BY SLAG IN PRESENCE OF STEEL

Zirconia is usually utilised in Submerged Entry Nozzle (SEN) in the slag contact zone, because of its high resistance to corrosion. However inconsistency of component performance and apparently erratic behaviours, in terms of corrosion rate, are frequently experienced. An important cause of the unexplained variability of component performance is the typical trial-and-error approach used to develop materials for the specific applications, and the “Darwinian selection” for the choice of the most suitable material despite the fact that a number of studies are available in literature. As a matter of fact, although almost all the mechanisms that have been proposed are based on some form of cyclic mechanism where the oxide is attacked by the slag and the exposed graphite is then attacked by the metal, contradictory conclusions can be often found about specific features. It is not to be excluded that contradictory results could be dependant on the experimental conditions used. In this paper laboratory experiments have been carried out, using together slag and steel, in order to clarify their role on the global corrosion mechanism. The results showed that, besides the dissolution of carbon in steel and oxide in slag, other phenomena contribute to the corrosion. In particular the experiments put in evidence the critical role of steel in dissolving the products of reactions between slag components and carbon, pushing the attack of slag to carbon. The consequence is that the corrosion phenomenon is complex, and parameters such as activity of slag components, porosity of refractory matrix, characteristics of carbon material are involved in the tendency of the carbon to react with slag, hence on the global corrosion rate

Advanced laboratory testing methods using real-time simulation and hardware-in-the-loop techniques : a survey of smart grid international research facility network activities

The integration of smart grid technologies in interconnected power system networks presents multiple challenges for the power industry and the scientific community. To address these challenges, researchers are creating new methods for the validation of: control, interoperability, reliability of Internet of Things systems, distributed energy resources, modern power equipment for applications covering power system stability, operation, control, and cybersecurity. Novel methods for laboratory testing of electrical power systems incorporate novel simulation techniques spanning real-time simulation, Power Hardware-in-the-Loop, Controller Hardware-in-the-Loop, Power System-in-the-Loop, and co-simulation technologies. These methods directly support the acceleration of electrical systems and power electronics component research by validating technological solutions in high-fidelity environments. In this paper, members of the Survey of Smart Grid International Research Facility Network task on Advanced Laboratory Testing Methods present a review of methods, test procedures, studies, and experiences employing advanced laboratory techniques for validation of range of research and development prototypes and novel power system solutions

Etude par angioscintigraphie des effets de la stimulation ventriculaire gauche chez des patients en insuffisance cardiaque avec bloc de branche gauche (analyse systolique et diastolique)

BREST-BU Médecine-Odontologie (290192102) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Definitions, adjudication, and reporting of pulmonary embolism-related death in clinical studies: a systematic review.

BACKGROUND Pulmonary embolism (PE)-related death is a component of the primary outcome in many venous thromboembolism (VTE) studies. The absence of a standardized definition for PE-related death hampers study outcome evaluation and between-study comparisons. OBJECTIVES To summarize definitions for PE-related death used in recent VTE studies and to assess the PE-related death rate. PATIENTS/METHODS A systematic literature search was conducted on April 26 , 2018 from January 1 , 2014 up to the search date in MEDLINE, Embase, and CENTRAL. Cohort studies and randomized trials in which PE-related death was included in the primary outcome were eligible. Screening of titles, abstracts, and full-text articles, and data extraction were independently performed in duplicate by two authors. Study outcomes included the definition for PE-related death, VTE case-fatality rate, and death due to PE rate. Descriptive statistics were used to analyze the data. RESULTS Of the 6,807 identified citations, 83 studies were included of which 27% were randomized trials, 31% were prospective and 42% retrospective cohort studies. Thirty-five studies (42%) had a central adjudication committee. Thirty-eight (46%) reported a definition for PE-related death of which the most frequently used components were 'autopsy-confirmed PE' (50%), 'objectively confirmed PE before death' (55%), and 'unexplained death' (58%). Median VTE case-fatality rate was 1.8% (interquartile range, 0.0 to 13). CONCLUSIONS Only half of the included studies reported definitions for PE-related death, which were very heterogeneous. Case-fatality rate of VTE events varied widely across studies. Standardization of the definition and guidance on adjudication and reporting of PE-related death is needed. This article is protected by copyright. All rights reserved

Influence de la position dorsale ou ventrale sur l'analyse de la viabilité en scintigraphie myocardique

BREST-BU Médecine-Odontologie (290192102) / SudocSudocFranceF

Compréhension élémentaire des propriétés physiques des matériaux compositesréfractaires à matrice carbonée

National audienceDe nos jours, la production d’acier avec des propriétés améliorées devient essentielle, mais presque impossiblesans le progrès dans la connaissance des matériaux réfractaires à matrice carbonée. Ces matériaux sont confrontés à desconditions sévères d’utilisations et font face à des contraintes thermomécaniques élevées et à la corrosion de l’acier enfusion. Ces matériaux réfractaires doivent donc avoir des propriétés spécifiques telles qu’une faible dilatation entempérature et un module d’Young peu élevé, une haute conductivité thermique et une faible réactivité chimique avecl’acier afin d’avoir une bonne résistance aux chocs thermiques. Certaines familles de réfractaires notamment celles àmatrice carbonée présentent un comportement mécanique non-linéaire en service, du fait de leur structure spécifique,même lorsque ces matériaux sont testés à température ambiante. Comparativement à des matériaux ayant uncomportement mécanique linéaire, cette caractéristique entraîne une valeur élevée de la déformation à la rupture,couplée avec une contrainte à la rupture plus faible. Par conséquent, une meilleure compréhension de ces matériaux, enparticulier des interactions entre leurs différents composants et de leur influence sur les propriétés thermo-physiquesmacroscopiques est vital.Afin de parvenir à cette compréhension, des matériaux modèles à matrice carbonée, utilisant des précurseursorganiques pour la matrice et des oxydes comme charge minérale ont été élaborés, en vue de comprendre lesinteractions entre la matrice carbonée et les particules d’oxyde. Les matériaux ont été étudiés grâce à différentesméthodes de caractérisation, tel que la microscopie électronique à balayage, le module d’Young et l’analyse dedilatation thermique. En fonction de la fraction volumique d’oxyde, il apparaît deux types de structures différentes : lapremière consiste en une matrice carbonée amorphe contenant des particules d’oxyde bien dispersées et l’autre est unréseau de particules d’oxyde connectées entre elles, liées par le carbone amorphe. En raison de la différence dedilatation entre le carbone amorphe et les particules d’oxyde, des microfissures se sont développées dans lamicrostructure soit au niveau des interfaces carbone/oxyde, soit au sein de la matrice carbonée elle-même. Les résultatsprésentés sur ces matériaux modèles ont révélés que les propriétés thermomécaniques de ces matériaux peuvent êtreconçues en adaptant la microstructure

Accurate Wavelength Drift Measurements of NGPON2 Tunable Lasers Candidates

International audience<p>We describe a heterodyne detection method able to measure precisely the wavelength drift of directly modulated lasers under burst mode operation. In addition to the thermal drift (up to 25GHz), the adiabatic chirp frequency modulation should not be neglected.</p