27 research outputs found
Monitoring and lifetime prediction of pvc cables: methodology by multiscale and multidisciplinary approach
Monitoring of the PVC cables as well as the prediction of their residual lifetime are
important issues for the maintenance of the French nuclear power plants (NPPs). To date, the
unanimously end of life criterion admitted for these cables is a 50% value of elongation at break
and, to our knowledge, only destructive tests give access to this parameter. This study reports a
relationship between elongation at break of the PVC and their plasticizer content. This
correlation opens the door to a monitoring directly on site or by micro sampling since all classic
laboratory techniques able to measure this content become ways to judge the condition of the PVC
sheaths and insulators. In addition, this study demonstrates the feasibility of
prediction of industrial PVC behavior changes. This model, adapted to the case of thin films,
involved tools of chemical kinetics and the implementation of a constitutive model
Metabolic profiling identifies trehalose as an abundant and diurnally fluctuating metabolite in the microalga Ostreococcus tauri
© 2017, The Author(s).Introduction: The picoeukaryotic alga Ostreococcus tauri (Chlorophyta) belongs to the widespread group of marine prasinophytes. Despite its ecological importance, little is known about the metabolism of this alga. Objectives: In this work, changes in the metabolome were quantified when O. tauri was grown under alternating cycles of 12 h light and 12 h darkness. Methods: Algal metabolism was analyzed by gas chromatography-mass spectrometry. Using fluorescence-activated cell sorting, the bacteria associated with O. tauri were depleted to below 0.1% of total cells at the time of metabolic profiling. Results: Of 111 metabolites quantified over lightâdark cycles, 20 (18%) showed clear diurnal variations. The strongest fluctuations were found for trehalose. With an intracellular concentration of 1.6 mM in the dark, this disaccharide was six times more abundant at night than during the day. This fluctuation pattern of trehalose may be a consequence of starch degradation or of the synchronized cell cycle. On the other hand, maltose (and also sucrose) was below the detection limit (~10 ΌM). Accumulation of glycine in the light is in agreement with the presence of a classical glycolate pathway of photorespiration. We also provide evidence for the presence of fatty acid methyl and ethyl esters in O. tauri. Conclusions: This study shows how the metabolism of O. tauri adapts to day and night and gives new insights into the configuration of the carbon metabolism. In addition, several less common metabolites were identified
Joint Power and Rate Adaptation in Ad Hoc Networks based on Coupled Interference
International audienc
Adaptive Compensation Signal for A Wheelchair Control using Anfis Model
International audienceno abstrac
Doppler Shift Compensation Schemes in VANETs
Over the last decade vehicle-to-vehicle (V2V) communication has received a lot of attention as it is a crucial issue in intravehicle communication as well as in Intelligent Transportation System (ITS). In ITS the focus is placed on integration of communication between mobile and fixed infrastructure to execute road safety as well as nonsafety information dissemination. The safety application such as emergence alerts lays emphasis on low-latency packet delivery rate (PDR), whereas multimedia and infotainment call for high data rates at low bit error rate (BER). The nonsafety information includes multimedia streaming for traffic information and infotainment applications such as playing audio content, utilizing navigation for driving, and accessing Internet. A lot of vehicular ad hoc network (VANET) research has focused on specific areas including channel multiplexing, antenna diversity, and Doppler shift compensation schemes in an attempt to optimize BER performance. Despite this effort few surveys have been conducted to highlight the state-of-the-art collection on Doppler shift compensation schemes. Driven by this cause we survey some of the recent research activities in Doppler shift compensation schemes and highlight challenges and solutions as a stock-taking exercise. Moreover, we present open issues to be further investigated in order to address the challenges of Doppler shift in VANETs
New combined polymer-chromium approach for investigating the phototransformations involved in hologram formation in dichromated poly(vinyl alcohol)
International audienc
Lung CT image registration using regular step gradient descent optimisation algorithm
International audienceno abstrac
Monitoring and lifetime prediction of pvc cables: methodology by multiscale and multidisciplinary approach
Monitoring of the PVC cables as well as the prediction of their residual lifetime are
important issues for the maintenance of the French nuclear power plants (NPPs). To date, the
unanimously end of life criterion admitted for these cables is a 50% value of elongation at break
and, to our knowledge, only destructive tests give access to this parameter. This study reports a
relationship between elongation at break of the PVC and their plasticizer content. This
correlation opens the door to a monitoring directly on site or by micro sampling since all classic
laboratory techniques able to measure this content become ways to judge the condition of the PVC
sheaths and insulators. In addition, this study demonstrates the feasibility of
prediction of industrial PVC behavior changes. This model, adapted to the case of thin films,
involved tools of chemical kinetics and the implementation of a constitutive model