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261.
Galli R. Tenca A.F. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2004,12(1):52-66
The use of online arithmetic was often proposed for hardware implementations of complex digital-signal processing (DSP) algorithms. However, several important issues in the design process of such algorithms using online arithmetic are rarely discussed in the literature. This paper presents these issues and provides a methodology to analyze the behavior of networks of online arithmetic modules performing serial computation over fixed-point numbers. The methodology is presented, applied in several examples, and finally used to design an efficient field programmable gate arrays implementation of the Levinson-Durbin algorithm in an application of the Yule-Walker power spectrum estimation. The methodology can be applied to other algorithms as well and it simplifies the task of designing and verifying a network of online modules. The experimental results show the advantages of online arithmetic in the design of complex DSP algorithms. 相似文献
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P. Budrugeac J. M. Criado F. J. Gotor J. Malek L. A. Prez‐Maqueda E. Segal 《国际化学动力学杂志》2004,36(6):309-315
The isoconversional method suggested by Friedman and the invariant kinetic parameters method (IKP) were used in order to examine the kinetics of the nonisothermal crystallization of (GeS2)0.3(Sb2S3)0.7. The objective of the paper is to show the usefulness of the IKP method both for determining the activation parameters as well as the model of the investigated process. It was shown that the kinetic triplet [(E, A, f(α), where E is the activation energy, A is the preexponential factor, and f(α) is the differential function of conversion], which results through the application of the IKP method, depends on the set of kinetic models considered. For different sets of kinetic models, proportional values of f(α) are obtained. A criterion for the selection of this set, the use of which lead to the true kinetic triplet corresponding to the analyzed process (E = 163.2 kJ mol?1; A = 2.47 × 1012 min?1 and the Avrami‐Erofeev model, Am, for m = 2.5–2.6 was suggested. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 309–315, 2004 相似文献
266.
Paul F.Smith Sameer M.Prabhu Jonathan H.Friedman 《电子设计应用》2008,(5):88-92
本文引入了基于模型设计的概念,突出了其中的一些优点,详细讨论了组织中采用基于模型设计文化的10个最佳策略。这些最佳策略从不同工业领域的公司中收集,包括向基于模型设计的成功或者不成功的过渡。 相似文献
267.
Kargl F. Papadimitratos P. Buttyan L. Müter M. Schoch E. Wiedersheim B. Ta-Vinh Thong Calandriello G. Held A. Kung A. Hubaux J.-P. 《Communications Magazine, IEEE》2008,46(11):110-118
Vehicular communication systems are on the verge of practical deployment. Nonetheless, their security and privacy protection is one of the problems that have been addressed only recently. In order to show the feasibility of secure VC, certain implementations are required. In [1] we discuss the design of a VC security system that has emerged as a result of the European SeVe- Com project. In this second article we discuss various issues related to the implementation and deployment aspects of secure VC systems. Moreover, we provide an outlook on open security research issues that will arise as VC systems develop from today?s simple prototypes to fullfledged systems. 相似文献
268.
F. Ati S. El-Aoufi A. Chergui H. Y. Aboul-Enein B. Maouche 《Journal of the Iranian Chemical Society》2008,5(3):506-513
This paper describes khellin hydrolysis mechanism using semiemperical PM3 implemented in Gaussian 03 package. The calculations show that in the presence of an acidic media, an enolate molecular ion leads directly to ω-acetokhellinone while in the basic media it leads to khellinone. 相似文献
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F. Mattioni P.M. Weaver K.D. Potter M.I. Friswell 《International Journal of Solids and Structures》2008,45(2):657-675
This paper models the non-linear flexural response of laminates that have piecewise variation of lay-up in the planform, using finite element analysis. Attention is focused on the effects that thermal stresses have on the potential multiple shapes of a composite structure. Unsymmetric laminates may possess more than a single equilibrium configuration, and during the cool-down the solution thus bifurcates at a critical temperature. In static analyses, numerical solutions are often coaxed to converge into one or the other branch of the solution. A methodology to overcome this problem is presented. Such modelling is necessary to allow application of multistable composite within morphing aircraft structures as multistable composites could provide a viable solution for the realisation of shape-adaptable structures. 相似文献