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81.
Colaitis M.-J. Jumpertz J.-L. Guerin B. Cheron B. Battini F. De Lescure B. Gautier E. Geffroy J.-P. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1996,84(7):1019-1037
This paper provides a tutorial on the motivations, design, and applications of parallel processing applied to video real-time, illustrated by the experience gained in the implementation of the P3I machine. Its main purpose is to highlight the motivations for such a development the basic implementation choices, the major difficulties encountered and how they have been solved. Through these studies we found that parallel processing is well-suited to video real-time, when programmable implementations are considered. There are many outcomes of the P3I project, ranging from architectural considerations to parallel algorithms optimizations, and programming methodology. We want to emphasize three conclusions. First, programming an architecture composed of different parallel paradigms in a given architecture is tractable, and this heterogeneity is cost effective and efficient in terms of processing performances. Second, concerning the well known debate about how to match parallel architectures and image processing “levels” we conclude that the key is not to discuss Flynn's taxonomy (i.e., data versus tasks parallelism) but to consider how the parallelism grain evolves within a whole application. Third, we confirm that in the field of image processing, the efficiency of parallelism can only be gained if algorithms developers think “parallel”; this result seems to be obvious, but just consider the trends of recent RISC processors, embedding more and more parallelism, and claiming at a compatibility with existing sequential softwares 相似文献
82.
Sang-Il Han Author Vitae Author Vitae Lisane Brisolara Author Vitae Luigi Carro Author Vitae Author Vitae Xavier Guerin Author Vitae Author Vitae Kai Huang Author Vitae Author Vitae Xiaolang Yan Author Vitae 《Integration, the VLSI Journal》2009,42(2):227-245
As a solution for dealing with the design complexity of multiprocessor SoC architectures, we present a joint Simulink-SystemC design flow that enables mixed hardware/software refinement and simulation in the early design process. First, we introduce the Simulink combined algorithm/architecture model (CAAM) unifying the algorithm and the abstract target architecture. From the Simulink CAAM, a hardware architecture generator produces architecture models at three different abstract levels, enabling a trade-off between simulation time and accuracy. A multithread code generator produces memory-efficient multithreaded programs to be executed on the architecture models. To show the applicability of the proposed design flow, we present experimental results on two real video applications. 相似文献
83.
The BF3:Et2O catalysed Diele-Alder reaction of α-ethenylidene cyclanones constitutes a highly stereoselective route to spirocyclic dienones. 相似文献
84.
Bandwidth management and congestion control in plaNET 总被引:1,自引:0,他引:1
The protocols and mechanisms necessary for network bandwidth management and congestion control are addressed. The discussion draws heavily on the lessons learned from the design and implementation of plaNET, a high-speed packet-switching system for integrated voice, video, and data communications. A general overview of the mechanisms involved is given. The individual components of the system are discussed. Most of the conclusions are general and can be applied to other high-speed networks, including asynchronous transfer mode (ATM) systems 相似文献
85.
We present an overview of various aspects of the self-assembly of organic monolayers on silicon substrates for molecular electronics applications. Different chemical strategies employed for grafting the self-assembled monolayers (SAMs) of alkanes having different chain lengths on native oxide of Si or on bare Si have been reviewed. The utility of different characterization techniques in determination of the thickness, molecular ordering and orientation, surface coverage, growth kinetics and chemical composition of the SAMs has been discussed by choosing appropriate examples. The metal counterelectrodes are an integral part of SAMs for measuring their electrical properties as well as using them for molecular electronic devices. A brief discussion on the variety of options available for the deposition of metal counterelectrodes, that is, soft metal contacts, vapor deposition and soft lithography, has been presented. Various theoretical models, namely, tunneling (direct and Fowler-Nordheim), thermionic emission, Poole-Frenkel emission and hopping conduction, used for explaining the electronic transport in dielectric SAMs have been outlined and, some experimental data on alkane SAMs have been analyzed using these models. It has been found that short alkyl chains show excellent agreement with tunneling models; while more experimental data on long alkyl chains are required to understand their transport mechanism(s). Finally, the concepts and realization of various molecular electronic components, that is, diodes, resonant tunnel diodes, memories and transistors, based on appropriate architecture of SAMs comprising of alkyl chains (sigma- molecule) and conjugated molecules (pi-molecule) have been presented. 相似文献
86.
Guerin S Hayden BE Pletcher D Rendall ME Suchsland JP 《Journal of combinatorial chemistry》2006,8(5):679-686
A novel high-throughput technique has been developed for the investigation of the influence of supported metal particle size and the support on electrocatalytic activity. Arrays with a gradation of catalyst particle sizes are fabricated in a physical vapor deposition system that also allows selection of the support material. Simultaneous electrochemical measurements at all electrodes in the array, together with determination of the actual particle size distribution on each of the electrodes by transmission electron microscopy (TEM), then allows rapid determination of the activity as a function of catalyst center size. The procedure is illustrated using data for the reduction of oxygen on gold nanoparticles supported on both substoichiometric titanium dioxide (TiO(x)()) and carbon and the conclusions are verified using voltammetry at rotating disk electrodes. Gold centers with diameters in the range 1.4-6.3 nm were investigated and it is demonstrated that, with both supports, the catalytic activity for oxygen reduction decays rapidly for particle sizes below 3.0 nm. This may be observed as a decrease in current at constant potential or an increase in the overpotential for oxygen reduction. 相似文献
87.
C.R. Parthasarathy M. Denais V. Huard G. Ribes D. Roy C. Guerin F. Perrier E. Vincent A. Bravaix 《Microelectronics Reliability》2006,46(9-11):1464-1471
Assessment of design implications due to degradation of CMOS devices is increasingly required in the latest technologies. This paper presents selected topics relevant to realize an efficient design-in reliability methodology in the latest generation CMOS technologies. NBTI is discussed in terms of characterization using On-The-Fly (OTF) methodology. Extension of OTF method is discussed using bias patterns to gain insights into NBTI under analog operation. A reliability simulation methodology is discussed against requirements for optimization and integration within an existing design flow. The features of this methodology are illustrated using some simple design examples. 相似文献
88.
89.
R. Guerin E. H. El Ghadraoui M. Sergent P. Monceau 《Journal of solid state chemistry》1983,50(3):304-311
The M2Re5As12 arsenides (M = Fe, Co, Ni) and the Co2Re5P12 phosphide were synthesized. The unit cell is orthorhombic with space group Pnnm and contains two formula units. The X-ray structure of Ni2Re5As12 was studied from three-dimensional single-crystal counter data and was refined down to R = 0.048 for 637 independent reflections. The structure can be described as built up from two different structural domains; the first one is the marcasite type and shows As---As pairs and linear Re---Re chains, the second one consists of Re4 clusters with common edges linked to terminal Ni atoms. A nearly temperature-independent paramagnetism and p-type metallic conduction were observed from the magnetic and electrical measurements. Also observed in this new family of compounds were the resistivities along and perpendicular to the c axis and their anisotropic behavior. 相似文献
90.