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1.
The evolutionary design can produce fast and efficient implementations of digital circuits. It is shown in this paper how evolved circuits, optimized for the latency and area, can increase the throughput of a manually designed classifier of application protocols. The classifier is intended for high speed networks operating at 100 Gbps. Because a very low latency is the main design constraint, the classifier is constructed as a combinational circuit in a field programmable gate array (FPGA). The classification is performed using the first packet carrying the application payload. The improvements in latency (and area) obtained by Cartesian genetic programming are validated using a professional FPGA design tool. The quality of classification is evaluated by means of real network data. All results are compared with commonly used classifiers based on regular expressions describing application protocols. 相似文献
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Open problems posed by Klir and Wierman (1998) for a nonspecificity measure are solved; the measure is proven additive, and its extension to nonconvex sets given. Several different proofs of additivity are given, to suggest certain techniques of wider applicability in system problems and to motivate further research possibihties. A study is initiated to refine nonspecificity separately to each dimension k≤n for the bodies residing in Rn. 相似文献
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Richard W. Hanks 《Chemical Engineering Communications》1990,89(1):187-194
Stokes' second problem, the propagation and damping of waves into a semi-infinite fluid generated by harmonic oscillations of a flat pate on the surface, is solved for the simple Bingham Theological constitutive model. The solution reveals the existence of “windows” in the distance-time-stress space in which shearing is possible whereas outside these restricted regions no shearing can occur. Within these restricted regions the wave forms developed are exponentially damped, traveling waves which propagate from the excitation plane into the fluid and disappear along definitely prescribed boundaries determined by the yield condition. The most significant consequence of the existence of these “windows” of shear is that even very small yield stresses will radically modify the induced velocity wave patterns from that which would be expected based upon the classical Newtonian fluid solution of Stokes' second problem. At least in this physical setting, it is not necessary for shear to occur globally for motion to occur anywhere, as has been postulated in some recent studies of complex motions. Thus, the motion is consistent with a simple Bingham model which does possess a yield stress. 相似文献
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在程序开发过程中利用VC中所见即所得编程技术,通过设置映射模式,统一输入参数单位,调用坐标转换和字体处理函数,将实际的坐标值和字体转换为基于输出设备对象的逻辑坐标值和字体,由程序实现在不同设备上输出一致的显示结果.该方法也可用于文字处理软件,实现文字编辑的所见即所得. 相似文献
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针对弹道飞行器空间飞行轨迹的大地坐标计算,从弹道计算的地心球坐标出发,给出一种利用空间几何关系的迭代法,避免了地心直角坐标的转换过程。通过与传统算法的对比分析,验证了该算法的有效性,并进一步明确了该算法的迭代初值,分析了该算法在弹道飞行器空间飞行轨迹大地坐标计算中的适用性。 相似文献
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Cao Zhi-fang Li Yi-tian Zhao Ming-deng Wuhan University of Hydraulic Electric Engineering Wuh an P.R.China 《水动力学研究与进展(B辑)》2000,12(3)
1. INTRODUCTIONIn 2 -D mathematical model of unsteady flow in open channel,one of the mostdifficulties is its slow convergence rate and too much time needed in computation.Themultigrid method is a new rapid iteration method developed in the resent 2 0 years. Now ithas been verified as an optimizing iteration method and its convergence rate has no relationswith mesh spacing.At present the multigrid method has been widely used in many fields(Liu Chaoqun,1 995;Peng Wenqi,1 994 ) ,especia… 相似文献
10.
有机电致发光器件各层厚度对色坐标的影响 总被引:1,自引:0,他引:1
采用真空蒸镀法制备了不同厚度的双层有机电致发光器件,器件结构为ITO/NPB/Alq3/Al。测得不同厚度的有机电致发光器件的色坐标,发现随有机层厚度值的增加,发光器件的色坐标x值增大,y值减小。为解释此现象,从光传输角度出发利用光传输矩阵理论分析了光从激发到射出器件的光耦合输出过程,建立了光输出模型并得出色坐标变化的原因是厚度变化引起相位的变化,从而影响了传输矩阵,这样透射率会随传输矩阵的改变而改变,色坐标的计算又与透射率有关,最终使色坐标发生改变。 相似文献