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61.
Claude Deslouis Bernard Tribollet Guiliano Mengoli Marco M. Musiani 《Journal of Applied Electrochemistry》1988,18(3):374-383
The electrochemical behaviour of a Cu rotating disc electrode in neutral aerated NaCl solution was investigated in the cathodic and anodic ranges and at the corrosion potential. In the cathodic range, where the reduction of oxygen takes place, reduction peaks allow the identification and quantitative evaluation of insoluble corrosion products (CuCl and Cu2O). In the anodic range Cu is dissolved, most likely as CuCl
2
–
. A new mechanism for the anodic dissolution is proposed after comparing our data with previously published mechanisms. Corrosion currents were found to decrease with time and to be a function of the rotation rate of the electrode. Both the mixed kinetics of the anodic partial reaction and diffusion through a porous layer seem to be relevant in controllingl
corr. 相似文献
62.
N. Fréty F. Bernard J. Nazon J. Sarradin J. C. Tedenac 《Journal of Phase Equilibria and Diffusion》2006,27(6):590-597
A study of copper (Cu) diffusion into silicon substrates through Ta nitride (TaN) and tantalum (Ta/TaN) layers was investigated
based on an experimental approach. TaN
x
and Ta/TaN
x
thin films were deposited by radiofrequency sputtering under argon (Ar) and Ar-nitrogen (N) plasma. The influence of the
N2 partial pressure on the microstructure and the electrical properties is reported. X-ray diffraction patterns showed that
the increase of the N2 partial pressure, from 2 to 10.7%, induces a change in the composition of the δTaN phase, from TaN to TaN1.13, as well as an evolution of the dominant crystallographic orientation. This composition change is related to a drastic increase
of the electrical resistivity over a N2 partial pressure of 7.3%. The efficiency of TaN layers and Ta/TaN multilayer diffusion barriers was investigated after annealing
at temperatures between 600 and 900 °C in vacuum. Secondary ion mass spectrometry profiles showed that Cu diffuses from the
surface layer through the TaN barrier from 600 °C. Cu diffusion mechanisms are modified in the presence of a Ta sublayer.
This article was presented at the Multicomponent-Multiphase Diffusion Symposium in Honor of Mysore A. Dayananda, which was
held during TMS 2006, the 135th Annual Meeting and Exhibition, March 12–16, 2006, in San Antonio, TX. The symposium was organized
by Yongho Sohn of the University of Central Florida, Carelyn E. Campbell of National Institute of Standards and Technology,
Richard D. Sisson, Jr., of Worcester Polytechnic Institute, and John E. Morral of Ohio State University. 相似文献
63.
Françoise Détienne Béatrice Cahour Marie-Christine Legout Bernard Gourvennec Marc Relieu Gilles Coppin 《Cognition, Technology & Work》2013,15(4):445-455
Based on the analysis of “real” Second Life meetings data, in educational and professional settings, our objective is to understand the actual uses of this kind of Virtual World and more particularly, the interactive frames constructed in SL meetings and their interrelation with uses of communication media. The originality of our analytical framework stems from the combination of two perspectives: a third view perspective based on analyses of observational data and a first view perspective based on users’ reports on their experience in SL. Our results highlight: boundaries between serious and recreational registers; avatar’s expression and attribution of feelings to the person “behind”; spatial positioning as indicators and constructors of roles and engagement; management of communication fluidity and joint focus; narrowing of communication media used for task focus content; emerging mediation role for management of fractured exchanges. 相似文献
64.
Elhadi Shakshuki Hsiang-Hwa Koo Darcy Benoit Daniel Silver 《Journal of Computer and System Sciences》2008,74(2):279-296
Electronic calendars are important tools that are used by consumers on a daily basis. However, scheduling a meeting that involves persons with different commitments and preferences remains a difficult task. Meeting scheduling is difficult because current calendaring applications cannot handle the responsibility of automatically and autonomously managing time slots. This paper presents a distributed multi-agent system architecture in which each person is represented by an agent. These agents automatically and autonomously work together to assist different users to book meetings on their behalf. Each agent has the capability to manage, negotiate and schedule tasks, meetings, events, appointments for its assigned user. In this multi-agent system, the agents coordinate their activities and negotiate on behalf of their associated users to find a solution that satisfies the users' meeting requirements and preferences. A prototype of this system is implemented to demonstrate how the agents can automatically book meetings. 相似文献
65.
Gilhuly TJ Hutchings SR Dumont GA Macleod BA 《Computer methods and programs in biomedicine》2008,89(2):179-188
The neuromuscular blocker advisory system (NMBAS) is a computer program developed to provide advisory guidance to anesthesiologists on the timing and dose of rocuronium to paralyze patients during surgery. It is believed that the use of such a system will administer the minimally effective amount of drug, maintaining the patient in a state of paralysis that is useful for surgery yet easily reversible. This will improve patient safety and result in more efficient care. In this paper we present the NMBAS, its basic methodology, and its development though a pilot study. Novel methods of handling neuromuscular response data are presented, including relaxation measurement and the enhanced-train-of-four sensing modality. New methods of handling nonlinearities at the neuromuscular junction to allow application of adaptive control techniques are presented. A novel form of modelling combining model swapping and RLSE adaptation to accommodate the patient variation seen with NMB drugs is introduced. A pilot study testing the NMBAS was undergone to prepare the NMBAS for application in a full clinical trial, in which patients undergoing prostate brachytherapy surgeries using rocuronium for intubation were admitted. 相似文献
66.
Inductive transfer with context-sensitive neural networks 总被引:1,自引:1,他引:0
Context-sensitive Multiple Task Learning, or csMTL, is presented as a method of inductive transfer which uses a single output neural network and additional contextual inputs
for learning multiple tasks. Motivated by problems with the application of MTL networks to machine lifelong learning systems,
csMTL encoding of multiple task examples was developed and found to improve predictive performance. As evidence, the csMTL method is tested on seven task domains and shown to produce hypotheses for primary tasks that are often better than standard
MTL hypotheses when learning in the presence of related and unrelated tasks. We argue that the reason for this performance
improvement is a reduction in the number of effective free parameters in the csMTL network brought about by the shared output node and weight update constraints due to the context inputs. An examination
of IDT and SVM models developed from csMTL encoded data provides initial evidence that this improvement is not shared across all machine learning models. 相似文献
67.
Aye Akbalk Sekoun Kebe Bernard Penz Najiba Sbihi 《International Transactions in Operational Research》2008,15(2):195-214
In this paper we study the coordination of different activities in a supply chain issued from a real case. Multiple suppliers send raw materials (RMs) to a distribution center (DC) that delivers them to a unique plant where the storage of the RMs and the finished goods is not possible. Then, the finished goods are directly shipped to multiple customers having just‐in‐time (JIT) demands. Under these hypotheses, we show that the problem can be reduced to multiple suppliers and one DC. Afterwards, we analyze two cases; in the first, we consider an uncapacitated storage at DC, and in the second, we analyze the capacitated storage case. For the first case, we show that the problem is NP‐hard in the ordinary sense using the Knapsack decision problem. We then propose two exact methods: a mixed integer linear program (MILP) and a pseudopolynomial dynamic program. A classical dynamic program and an improved one using the idea of Shaw and Wagelmans are given. With numerical tests we show that the dynamic program gives the optimal solution in reasonable time for quite large instances compared with the MILP. For the second case, the capacity limitation in DC is assumed, which makes the problem solving more challenging. We propose an MILP and a dynamic programming‐based heuristic that provides solutions close to the optimal solution in very short times. 相似文献
68.
In the ternary system Ti-Si-C, the ternary compound Ti3SiC2 seems to exhibit promising thermal and mechanical properties. Its synthesis as a thin film from the vapour phase is very difficult owing to the complexity of the system. A contribution to the knowledge of the CVD of Ti3SiC2 from a TiCl4-SiCl4-CH4-H2 gas mixture is proposed on the basis of a thermodynamic approach. This approach is based on a reliable estimation of Ti3SiC2 thermodynamic data in good accordance with recent experimental results on its thermal stability. A first equilibrium calculation for the deposition on an inert substrate shows the influence of the experimental parameters on the composition of both the deposit and the gas phase. As a result, the deposition of Ti3SiC2 can be favoured by an excess of TiCl4 ( 45%), a rather low pressure (10–20 kPa), high temperature ( 1273 K) and low H2 dilution ratio. On the basis of equilibrium calculations for various reactive substrates, complex mechanisms of Ti3SiC2 deposition are pointed out, with intermediate steps of substrate consumption, e.g. the formation of TiC from a carbon substrate or TiSi2 from a silicon substrate. 相似文献
69.
Chapellier Paul Lavenus Pierre Le Traon Olivier Dulmet Bernard 《Microsystem Technologies》2022,28(6):1485-1496
Microsystem Technologies - This paper presents recent advances on two dimensional length-extension mode (2D-LEM) quartz resonators providing high quality (Q) factor on resonances at a few MHz. The... 相似文献
70.
Hassen Ait Atmane Abdelouahed Tounsi Fabrice Bernard 《International Journal of Mechanics and Materials in Design》2017,13(1):71-84
The novelty of this paper is the use of an efficient beam theory for bending, free vibration and buckling analysis of functionally graded material (FGM) beams on two-parameter elastic foundation. The present theory accounts for both shear deformation and thickness stretching effects by a parabolic variation of all displacements across the thickness, and satisfies the stress-free boundary conditions on the upper and lower surfaces of the beam without requiring any shear correction factor. Due to porosities, possibly occurring inside FGMs during fabrication, it is therefore necessary to consider the vibration, bending and buckling behaviors of beams having porosities in this work. The equation of motion for FGM beams is obtained through Hamilton’s principle. The closed form solutions are obtained by using Navier technique, and then fundamental frequencies are found by solving the results of eigenvalue problems. The validity of the present theory is investigated by comparing some of the present in literature. It can be concluded that the proposed theory is accurate and simple in solving the bending, free vibration and buckling behaviors of FGM sandwich beams. 相似文献