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1.
莫宏伟  徐立芳 《电子学报》2013,41(5):1036-1040
 针对传统演化算法在设计数字逻辑电路时存在的演化速度缓慢和容易陷入局部最优解等问题,设计了一种Cartesian进化编程编码的电路演化Memetic算法,采用遗传算法作为全局搜索方法,并设计了适合电路演化的基本门种类局部搜索策略.通过一位全加器电路证明所提出的Memetic硬件演化算法的搜索能力,实验证明所提出的算法能够有效地完成进化任务,具有较强的全局快速和局部搜索能力.  相似文献   

2.
针对制约演化硬件技术发展所面临的可扩展性问题,提出了一种GD.BIE分解演化方法,它将待演化电路按照先输出分解后输入分解的顺序,逐步分解为多个子电路,最后将演化成功的子电路有规律的综合完成目标电路的演化设计。实验证明,该分解方法能有效解决大规模电路演化中存在的染色体编码长、最大适应度高、演化代数多、输入输出真值表组合复杂的问题,为较大规模电路演化提供了一种有效途径。  相似文献   

3.
针对传统WDCT图像压缩编码算法频率卷曲参数的难选取问题,提出了小生境演化算法下的WDCT图像压缩方法(NEAWDCT).利用小生境演化算法全局寻优的特点,与WDCT图像压缩编码方法相结合,达到自适应选取最优频率卷曲参数的目的.针对频率卷曲参数特征,设计染色体编码方式及演化算子,以加快收敛速度.由于图像能量多集中于低频部分,选择特定范围内的数值初始化种群,不仅能加快算法收敛速度,还保留了种群的多样性.实验结果表明,利用新的NEAWDCT算法生成的WDCT矩阵能有效提高峰值信噪比.  相似文献   

4.
硬件演化技术在电路演化过程中具有自组织、自适应、自修复性能,具有重要的工程应用价值,硬件演化技术能够实现的核心就是演化算法。目前中等规模及大规模电路演化的时候存在演化速度慢等缺陷,直接影响电路演化的时效性。提出了一种新颖的电路加速演化策略,即基于真值表分解的电路演化策略,从不同的角度对电路演化算法进行了改进,有别于常规的改进演化算法。通过对典型电路进行仿真分析,证明了所提出的加速演化策略的有效性,并且具有重要的应用价值。  相似文献   

5.
基于Xilinx Virtex-Ⅱ系列FPGA控制逻辑块(CLB)矩阵特点以及每一个控制逻辑块能实现任何2输入1输出的逻辑功能的特点,提出了一种基于基因表达式程序设计的电路优化算法。在该算法中染色体由按线性方式连接的逻辑单元矩阵组成,采用的遗传操作包括变异和杂交,并利用真值表进行适应度评估。实验证明,所得到的电路结构优于传统方法。  相似文献   

6.
演化硬件(EvolvableHardware,EHW)是可编程逻辑器件和进化算法的结合,可根据不同演化目标自主动态调整自身电路结构.在演化硬件方法中,由于其自演化特性和上层遗传算法为参数敏感型,面对不同演化对象自适应性较差.同时遗传算法有早熟缺陷,在大型演化目标后期经常无法演化到目标真值表,成功率较低.本文在传统演化硬...  相似文献   

7.
提出一种基于演化算法的可测性调度分配方法.应用演化算法,在调度和分配过程中研究电路的可测性设计.该方法的贡献是:给出了三个可测性准则;设计了可测性目标函数;提出了一种新颖的演化编码和演化操作,提高了搜索速度和解的质量.实验结果验证了该方法的可行性.  相似文献   

8.
该文将量子计算与遗传算法进行融合,其核心是在常规遗传算法中将量子的态矢量引入遗传编码,并自适应地进行量子旋转门的调整以实现染色体的演化,使算法具有更好的种群多样性和全局寻优能力。通过求解计算机通信网优化问题的实例,结果表明:新方法比采用常规遗传算法具有明显的高效性。  相似文献   

9.
TN7 2004040451用遗传算法实现信号转换电路的非线性校正/温秀兰,宋爱国,崔建伟,(2{高桂本(东南大学)11数据采集与处理一2003,18(3)一306一309采用了遗传算法的最新成果,提出了一种新颖的基于实数编码的改进遗传算法用以校正信号转换电路的非线性误差.该算法采用基于代沟最小的  相似文献   

10.
演化硬件作为新的硬件载体,具有自组织、自适应、自修复的能力。本文设计了一种由查找表(LUT)和D触发器构成的基本演化硬件单元,能够满足组合逻辑电路和时序逻辑电路的设计要求。同时设计了兼容组合逻辑电路和时序逻辑电路的适应度评估函数。利用该模型对基于遗传算法的演化硬件和基于猴王遗传算法的演化硬件参数进行了优化设计。分析表明遗传算法的变异概率 取值应在0~0.01之间,交叉概率对算法的性能影响可以忽略;猴王遗传算法的保留概率 取值应在0~0.85之间,变异概率 应在0~0.01之间。对比分析了遗传算法和猴王遗传算法的性能:基于猴王遗传算法演化硬件的运算量只有基于遗传算法演化硬件的1/4,且能得到更接近目标电路的电路结构。  相似文献   

11.
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.  相似文献   

12.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

13.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

14.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

15.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

16.
Waveguide multilayer optical card (WMOC) is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling & processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic (VB) language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.  相似文献   

17.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  相似文献   

18.
It is a key problem to accurately calculate beam spots' center of measuring the warp by using a collimated laser. A new method, named double geometrical center method (DGCM), is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device (CCD) is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What's more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.  相似文献   

19.
The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.  相似文献   

20.
Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.  相似文献   

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