150 research outputs found
Structural, magnetic and magnetocaloric properties of Pr0.6-xErxSr0.4MnO3 (x=0.0, 0.1 and 0.2)
No full textInternational audienceWe investigate the effect of Erbium doping on the structural, magnetic and magnetocaloric properties of Pr0.6-xErxSr0.4MnO3 (x = 0.0, 0.1 and 0.2) powder samples. Our polycrystalline samples were synthesized using the solid-state reaction at high temperature. X-ray diffraction characterizations showed that all our studied samples crystallize in the distorted orthorhombic system with Pnma space group. All our synthesized samples exhibit a paramagnetic-ferromagnetic transition with decreasing temperature. The magnetic transition temperature T-C is found to decrease continuously with increasing Er concentration. It was found that the maximum value of the magnetic entropy change for Pr0.4Er0.2Sr0.4MnO3 sample reached vertical bar Delta S-M(max)vertical bar = 2.40 J kg(-1) K-1 in a magnetic applied filed of 2T
Effect of barium-deficiency on the structural, magnetic, and magnetocaloric properties of La0.6Sr0.2Ba0.2-x square xMnO3 (0 <= x <= 0.15)
No full textInternational audienceStructural, magnetic, and magnetocaloric properties of La0.6Sr0.2Ba0.2-x square xMnO3 (0 <= x <= 0.15) where square is a barium deficiency have been investigated by X-ray diffraction and magnetic measurements. Our samples were synthesized using the solid-state reaction method at high temperatures. Structural studies show that our samples are single phase and crystallize in the rhombohedral system with R (3) over barc space group. Magnetization measurements as a function of temperature in a magnetic applied field of 0.05 T show that all our samples exhibit a paramagnetic-ferromagnetic transition with decreasing temperature. The Curie temperature T-C shifts to lower values with increasing barium-deficiency. The Arrott plots show that the phase transition is of second order. The effect of barium deficiency on the magnetocaloric properties has been investigated. The values of the maximum of the magnetic entropy change, vertical bar-Delta S-max vertical bar, under a magnetic field change of 3.5 T are found to be 2.9, 2.92, 3.31, and 3.34 J/kg K for x = 0.0, 0.05, 0.1, and 0.15, respectively
Automatic Configuration of PVCs in ATM Networks
No full textThis paper describes an agent-based approach to the automatic provision of Permanent Virtual Channels (PVC) in ATM networks. The agent framework described fosters flexibility and seamless evolution by the definition of capability skills. Skills are plugged into the agent's brain which is responsible for the coordination of the agent's behavior. The application of this agent framework to the problem of PVC configuration resulted in the definition of a set of skills, among which, only one skill is device-dependent. Therefore, the implemented application can easily support new types of ATM switches. Moreover, it is efficient in terms of performance and bandwidth saving
Strategic Analysis of Products Related to the Integration of Human Judgement into Demand Forecasting
No full textFor companies proposing a large offer of products and services, it is important to identify the products for which the forecast quality is critical. The objective of this paper is to propose a strategic analysis of the products in order to determine priorities in the demand forecasting process: (1) a high priority class including the products for which forecast accuracy has a strong impact on the logistic performance of the company and where judgement should be integrated in the forecasting process; (2) a low priority class with the remaining products for which forecast accuracy is less important and where forecasts could be established in an automated way. The classification process takes into account different criteria chosen on the basis of cost efficiency reasoning.LGP
Flexible Software Agents for the Automatic Provision of PVCs in ATM Networks
No full textThis paper describes an agent-based approach to the automatic provision of Permanent Virtual Channels (PVC) in ATM networks. The agent framework described fosters flexibility and seamless evolution by the definition of capability skills. Skills are plugged into the agent's brain which is responsible for the coordination of the agent's behavior. The application of this agent framework to the problem of PVC configuration resulted in the definition of a set of skills, among which, only one skill is device-dependent. Therefore, the implemented application can easily support new types of ATM switches. Moreover, it is efficient in terms of performance and bandwidth saving
Sodium – Deficiency effects on the structural, magnetic and magnetocaloric properties of La 0.8 Na 0.2−x □ x MnO 3 (0 ≤ x ≤ 0.15)
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Screening of the synthesis route on the structural, magnetic and magnetocaloric properties of La 0.6 Ca 0.2 Ba 0.2 MnO 3 manganite: A comparison between solid-solid state process and a combination polyol process and Spark Plasma Sintering
No full textLa0.6Ca0.2Ba0.2MnO3 ceramics are prepared by an original route, combining soft chemistry and Spark Plasma Sintering, within a few minutes at 700 degrees C and by the solid-state reaction at high temperatures with an annealing temperature of 1200 degrees C. We have studied the leverage of the powder synthesis method on the structural, morphological, magnetic and magnetocaloric properties of the samples. X-ray diffraction analysis using Rietveld refinement revealed that our materials crystallize in the rhombohedral system with R(3) over bar c space group for the sample prepared by the Polyol-Spark Plasma Sintering method and in the orthorhombic structure with Pbnm space group for the sample synthesized by the solid-state reaction. Magnetization measurements versus temperature under magnetic applied field of 0.05 T show a paramagnetic-ferromagnetic phase transition for both samples. The Arrott plots reveal that ours materials undergo a second-order phase transition. The maximum values of the magnetic entropy change (-Delta S-M(max)) under the magnetic field change of 5 T are 2.4 and 4.7 J/kg K for La0.6Ca0.2Ba0.2MnO3 synthesized by using solid-state reaction and Polyol-Spark Plasma Sintering methods respectively. The highest value of the relative cooling power RCP is found to be 244 J/kg for the Polyol-Spark Plasma Sintering sample under 5 T. These results are interesting enough and suggest that the Polyol-Spark Plasma Sintering synthesis method is a feasible route to prepare high quality perovskite material for magnetic cooling application. (C) 2017 Elsevier B.V. All rights reserved
High-speed data access with enhanced interference suppression over wideband cdma networks
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