Search results for "Nod"
showing 10 items of 4007 documents
Charge transport in electrically responsive polymer layers
2007
The processes of charge transport in the conducting polymer electrochromic films have been studied by means of spectral-electrochemical method, impedance spectroscopy and cyclic voltametry measurements. It has been shown that charge transport during the coloration-bleaching processes is not symmetric phenomenon. By means of impedance spectroscopy the effective diffusion coefficients for anode and cathode charge transport have been measured. The higher rate of charge transport in the bleaching process as compared to coloration is considered in the frame of conformation rebuilding of conducting polymer chains.
Three dimensional PEDOT nanowires network
2016
Abstract A three dimensional (3D) structure of poly(3,4-ethylenedioxythiophene) (PEDOT) nanowires have been prepared by electrochemical polymerization using 3D-alumina templates. The templates were synthesized by pulse anodization in an electrochemical bath. A 3D free standing network has been obtained after the template removal. The morphological analysis by electron microscopy shows the existence of a 3D PEDOT nanowires network whose nanowire diameter is around 20 nm for the vertical nanowires and 10 nm for the transversal connections. Electrical properties such as the I–V characteristics and the Seebeck coefficient were studied for the nanowires network. Also, the optical properties have…
Design of experiment approach applied to reducing and oxidizing tolerance of anode supported solid oxide fuel cell. Part I: Microstructure optimizati…
2011
The main drawback of Ni/YSZ anode supports for solid oxide fuel cell application is their low tolerance to reducing and oxidizing (RedOx) atmosphere changes, owing to the Ni/NiO volume variation. This work describes a structured approach based on design of experiments for optimizing the microstructure for RedOx stability enhancement. A full factorial hypercube design and the response surface methodology are applied with the variables and their variation range defined as: (1) NiO proportion (40-60 wt% of the ceramic powders), (2) pore-former proportion (0-30 wt% corresponding to 0-64 vol.%), (3) NiO particle size (0.5-8 mu m) and (4) 8YSZ particle size (0.6-9 mu m).
An Efficient Immunization Strategy Using Overlapping Nodes and Its Neighborhoods
2018
International audience; When an epidemic occurs, it is often impossible to vaccinate the entire population due to limited amount of resources. Therefore, it is of prime interest to identify the set of influential spreaders to immunize, in order to minimize both the cost of vaccine resource and the disease spreading. While various strategies based on the network topology have been introduced, few works consider the influence of the community structure in the epidemic spreading process. Nowadays, it is clear that many real-world networks exhibit an overlapping community structure, in which nodes are allowed to belong to more than one community. Previous work shows that the numbers of communit…
Diversity and phylogeography of Southern Ocean sea stars (Asteroidea)
2019
How is life distributed on the Southern Ocean sea floor? How can we explain species distribution patterns, their origin and the underpinning drivers? These questions are central to macroecological studies, especially in regions facing fast environmental changes. The main objective of this thesis was to describe and characterise distribution patterns of sea stars species (Echinodermata: Asteroidea) with regards to reproductive strategy (i.e. brooding versus broadcasting), a key life history trait for species dispersal. I tested whether contrasting dispersal abilities between direct developers (brooders) and species with pelagic larvae in their development (broadcasters) result in distinct di…
LoRa-Based Sensor Node Energy Consumption with Data Compression
2021
In this paper simple temporal compression algorithms' efficiency to reduce LoRa-based sensor node energy consumption has been evaluated and measured. It is known that radio transmission is the most energy consuming operation in a wireless sensor node. In this paper three lightweight compression algorithms are implemented in an embedded LoRa platform to compress sensor data in on-line mode and the overall energy consumption is measured. Energy consumption is compared to the situation without implementing any compression algorithm. The results show that a simple compression algorithm is an effective method to improve the battery powered sensor node lifetime. Despite the radio transmission's h…
A Virtual Tool for Load Flow Analysis in a Micro-Grid
2020
This paper proposes a virtual tool for load flow analysis in energy distribution systems of micro-grids. The solution is based on a low-cost measurement architecture, which entails low-voltage power measurements in each secondary substation and a voltage measurement at the beginning of the medium voltage (MV) feeder. The proposed virtual tool periodically queries these instruments to acquire the measurements. Then, it implements a backward&ndash
Nanostructured Ni Based Anode and Cathode for Alkaline Water Electrolyzers
2019
Owing to the progressive abandoning of the fossil fuels and the increase of atmospheric CO2 concentration, the use of renewable energies is strongly encouraged. The hydrogen economy provides a very interesting scenario. In fact, hydrogen is a valuable energy carrier and can act as a storage medium as well to balance the discontinuity of the renewable sources. In order to exploit the potential of hydrogen it must be made available in adequate quantities and at an affordable price. Both goals can be potentially achieved through the electrochemical water splitting, which is an environmentally friendly process as well as the electrons and water are the only reagents. However, these devices stil…
Energy Efficiency Evaluation of Dynamic Partial Reconfiguration in Field Programmable Gate Arrays: An Experimental Case Study
2018
Both computational performances and energy efficiency are required for the development of any mobile or embedded information processing system. The Internet of Things (IoT) is the latest evolution of these systems, paving the way for advancements in ubiquitous computing. In a context in which a large amount of data is often analyzed and processed, it is mandatory to adapt node logic and processing capabilities with respect to the available energy resources. This paper investigates under which conditions a partially reconfigurable hardware accelerator can provide energy saving in complex processing tasks. The paper also presents a useful analysis of how the dynamic partial reconfiguration te…
A Space-Time Meshless Method for Heat Transfer Problems With High Discontinuities
2013
The aim of this research is the development of a space-time driscretization method based on Diffuse Approximation Meshless method. This method, devoted to transient heat transfer problems presenting high temporal discontinuities, avoids any Finite-Difference time stepping procedure. The space-time discretization proposed here seems to be convenient for continuous transient heat transfer. Nevertheless, for problems including temporal discontinuities, some spurious oscillations, whose amplitudes depend on source power, appear. A new weight function respecting the principle of causality, based on a modification of the involved node’s selection and a normalisation of the distances, is developed…