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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   
2.
This article presents a heuristic which combines the orthogonal array experiment technique and an ant direction hybrid differential evolution algorithm (ADHDEOA) for planning of a large-scale passive harmonic filters problem. The addressed problem has a multi-bus and under abundant harmonic current sources in the system. In this study, an orthogonal array is first conducted to obtain the initial solution. Next, an ant direction hybrid differential evolution (ADHDE) is applied to search for a near optimum solution. The objective is to minimize the cost of the filter, the total demand distortion of harmonic currents and the total harmonic distortion of voltages at each bus simultaneously. In order to determine a set of weights of each term in the objective function, the simplest and most efficient form of triangular membership functions has been considered. The designed heuristic ADHDEOA is applied to a practical harmonic problem in a steel plant, and three design schemes are compared to demonstrate the performance of the ADHDEOA.  相似文献   
3.
AutoCAD是一种人机交互的绘图软件,本身并不具备参数化绘图功能,更不具备尺寸驱动功能,但用户可以利用其所提供的强大的二次开发语言AutoLISP、VisualLISP、VBA开发完全个性化的、性能更为优越的、具有尺寸驱动功能的参数化绘图软件。  相似文献   
4.
基于联合迭代重建技术的超声CT重建算法   总被引:2,自引:0,他引:2  
王浩全 《计算机应用》2010,30(7):1844-1846
在研究超声CT成像原理的基础上,对阵列检测方法进行了探讨。通过对探头布置方式的改进,增加了成像所需的数据量。基于最小二乘方准则,利用联合迭代重建算法,采用四边扫描算法求解相关系数矩阵,通过不断修正误差逼近真实值,进而实现速度矩阵的求取。数值仿真表明:采用上述方法能够明显减小重建误差,改善层析成像效果。  相似文献   
5.
A planar voltammetric sensor array for use in an electronic tongue was fabricated using a combination of microfabrication techniques. The techniques of e-beam evaporation and pulsed laser deposition were applied to prepare a device that contained all of the electrodes integrated on a silicon die (6 mm × 6 mm). The working electrodes were metals gold, platinum, iridium and rhodium. They were characterized by SEM and EDX, and by electrochemical investigation of the packaged dies with cyclic voltammetry in solutions of sulfuric acid and of ferrocene carboxylic acid in aqueous buffer solution. The robustness and reproducibility of the devices were assessed by potential cycling in acid solution.  相似文献   
6.
In this paper, we consider finite-time control problems for linear multi-agent systems subject to exogenous constant disturbances and impulses. Some sufficient conditions are obtained to ensure the finite-time boundedness of the multi-agent systems, which could be then reduced to a feasibility problem involving linear matrix inequalities. Numerical examples are given to illustrate the results.  相似文献   
7.
Basic finite-automaton characteristics are established for the class of all linear automata and information-lossless automata over a ring. The complexities of solving problems of parametric identification and initial-state identification are analyzed. The sets of fixed points for mappings realized by initial automata are characterized. Canonical forms are proposed for linear automata over the ring. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 60–74, May–June 2008.  相似文献   
8.
为提高动力电池使用效率,提出了一种基于FPGA的动力电池检测系统的设计方案.采用AD转换芯片实现对电池电压、电流的采集,数字温度传感器对温度进行采集,再通过软件实现对数据的处理和实时显示.系统运行稳定,数据处理能力强,集成度高,易于扩展.  相似文献   
9.
The ability to remember visual stimuli over a short delay period is limited by the small capacity of visual working memory (VWM). Here the authors investigate the role of learning in enhancing VWM. Participants saw 2 spatial arrays separated by a 1-s interval. The 2 arrays were identical except for 1 location. Participants had to detect the difference. Unknown to the participants, some spatial arrays would repeat once every dozen trials or so for up to 32 repetitions. Spatial VWM performance increased significantly when the same location changed across display repetitions, but not at all when different locations changed from one display repetition to another. The authors suggest that a major role of learning in VWM is to mediate which information gets retained, rather than to directly increase VWM capacity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
论述了应用Autolisp软件在机械设计CAD系统中,生成参数图的技术,介绍了参数的处理及编程技巧  相似文献   
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