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1.
量子遗传算法具有种群规模小,全局搜索能力强的特点被广泛应用于各类优化问题的求解.为了进一步提高量子遗传算法的收敛速度和搜索稳定性,克服算法的早熟问题,本文改进了基于自适应机制的量子遗传算法.在自适应量子遗传算法的基础上根据种群的适应度定义了个体相似度评价算子、个体适应度评价算子和种群变异调整算子及相应算子的计算方法,利用多算子协同评价当前种群状态并根据进化代数的变化,自适应的改变个体的变异概率,提高了算法全局寻优能力和收敛速度,降低了算法陷入局部寻优的概率.此外,为了提高算法的时间效率,将算法采用并行多宇宙的方式实现.实验结果表明,本文提出的算法在全局搜索性能、收敛速度和时间效率方面有较好的综合表现.  相似文献   

2.
针对MIMO雷达相位编码信号集的优化设计问题,提出一种改进正弦余弦优化算法.该算法通过引入Lévy飞行,扩大对目标点位置的搜索范围,防止陷入部分最佳;并设置控制参数,提高收敛速度,均衡全局搜索和局部搜索能力;借鉴粒子群算法的权重思想改变自适应更新方程,提高收敛精度,从而达到寻求最佳结果的目的.基于改进正弦余弦优化算法不仅设计出了相关性能良好的MIMO雷达相位编码信号集,而且与现有成果相比,该算法收敛速度和收敛精度均有明显提高.  相似文献   

3.
考虑到常规遗传优化算法进行电力配网系统的无功优化时,算法的早熟问题以及局部寻找最优解能力欠缺造成了优化结果收敛速度和收敛精度较低等问题,该文将自适应对偶种群、自适应终止条件以及全新的子代生成条件引入以形成一种改进型遗传优化算法,在种群迭代过程中保证种群的多样性以避免优化算法早熟现象,以及对优化算法的搜索效率进行加快以提高局部寻找最优解能力。通过实验IEEE57和IEEE30节点系统作为测试平台,使用常规遗传优化算法和可控交叉遗传算法(CCGA)与该文研究的改进遗传优化算法进行对比,使用相同的实验条件和实验数据进行测试。结果表明该文研究的改进遗传算法具有最好的优化效果,该算法计算得到的平均网损均低于其他优化算法,收敛精度和收敛速度更高,能够在局部最优解处跳出,距离目标函数的全局最优解更加接近。  相似文献   

4.
针对原始麻雀搜索算法在寻优过程中出现多样性降低,难以跳出局部最优,以及收敛精度不够等问题,提出一种基于混沌的多策略优化麻雀算法.首先,通过Circle混沌映射进行种群初始化,生成分布更加均匀的麻雀种群,增加种群的多样性;其次,引入自适应比例,对发现者的种群规模占种群总规模的比例进行动态变化,平衡算法的全局搜索与局部挖掘能力;然后引入Levy飞行改进发现者位置更新方式,提高算法的搜索范围与局部搜索能力,并且加快收敛于最优值的速度;最后,选择逐维变异与反向学习相融合的方式来扰动当前全局最优位置,通过贪婪算法来筛选出变异前后的最优值作为当前全局最优值,从而提高算法跳离局部最优的能力.本次选择12个基准函数和Wilcoxon秩和检验进行验证,并于六种其他算法进行对比,证明了以上多种策略对于算法的性能提升明显.同时,将该改进算法应用于工程实践中,本文选择压缩弹簧设计优化问题,验证所提改进算法在工程设计中的可行性与优越性.  相似文献   

5.
为了解决传统遗传算法在自动组卷中容易出现未成熟收敛和收敛速度慢等问题,提出了一种基于改进遗传算法的自动组卷方法。采用分段二进制编码策略,对每个子空间进行初始种群选择,保证了初始种群舍有丰富的模式,从而增加搜索收敛于全局最优的可能性。并对交叉算子和变异算子进行了优化,实现了交叉和变异概率随解的变化而自适应调整。实验结果表明,改进的遗传算法能有效地解决自动组卷问题,提高了收敛速度和组卷的成功率。  相似文献   

6.
张雪霞  陈维荣  戴朝华 《电子学报》2010,38(8):1825-1830
 提出将一种改进的差分进化算法——带局部搜索的动态多群体自适应差分进化算法(DMSDELS)应用于函数优化.该算法将种群中的个体随机动态分成多个子群体,以增强个体间的信息交换;变异操作中,选择最优个体为基向量,差分向量的方向选择有利于搜索的方向,以提高收敛速度;变异尺度因子F与交叉概率CR采用自适应机制,以平衡局部搜索与全局搜索;部分优秀个体搜索达到指定代数进入局部搜索,以加快收敛.通过对13个benchmark典型复杂函数进行测试,并与其他七种优化算法进行比较,仿真结果表明:DMSDELS算法具有较高的搜索精度和收敛性,且具有较强的跳出局部最优解能力.  相似文献   

7.
王毅  李晓梦  耿国华  周琳  段焱中 《电子学报》2021,49(12):2381-2389
为了提升粒子群算法的全局寻优与局部精细搜索能力并加快收敛速度,提出了基于直觉模糊熵的混合粒子群优化算法.该算法采用粒子的历史最优解信息构造直觉模糊熵的自适应函数,并将熵值作为扰动因子动态调节惯性权重,同时建立自适应全局最优粒子学习策略对扰动后的粒子进行训练,在保持多样性传播的基础上选择学习对象,使粒子探索更多新区域,实现种群间的协作与并行进化.通过仿真实验,将本文算法与两种衍生算法以及其他改进粒子群算法在11个测试函数上进行比较,结果表明,本算法在求解精度、收敛速度和寻优效率上均有更好表现.  相似文献   

8.
乾凡  游达章  张业鹏 《电子世界》2013,(23):144-145
为了提高遗传算法的搜索效率和收敛速度,本文给出了一种新的改进的遗传算法。该算法采用对群的优化来保持种群的多样性,保留历史最优个体并定期替换最优个体从而使得个体优化,对交叉概率和变异概率采用自适应的概率进行优化。通过对目标函数的测试表明,将改进遗传算法与基本遗传算法相比较,在函数最优值,平均收敛代数方面取得了令人满意的效果。  相似文献   

9.
基于遗传算法的亚100nm SOI MOSFET模型参数提取   总被引:1,自引:0,他引:1  
李尊朝  张瑞智  张效娟  林尧 《电子学报》2007,35(11):2033-2037
为了简化亚100nm SOI MOSFET BSIMSOI4的模型参数提取过程,实现全局优化,使用了遗传算法技术,并提出了保留多个最优的自适应遗传算法.该算法通过保留最优个体的多个拷贝,对适应度高和适应度低的个体分别进行诱导变异和动态变异,在进化起始阶段和终止阶段分别执行随机交叉和诱导交叉,既具有全局优化特性,又加速了局部搜索过程,提高了最终解的质量.不同种群数和进化代数条件下的参数提取实例表明,该算法提取精度高、速度快,全局优化稳定性好;适当增加种群数,有利于加速算法的全局收敛过程.  相似文献   

10.
针对当前雷达波形优化算法搜索策略单一、适用范围受限的问题,提出了一种基于改进混合量子遗传算法的二相编码雷达波形优化算法。所提算法采用了一种新的自适应旋转角度策略,根据迭代次数和余弦相似度动态调整旋转角度,提高了算法的收敛速度、全局搜索能力和求解质量。仿真结果表明,与遗传算法、基本量子遗传算法和混合量子遗传算法相比,对于包含了单峰、多峰和非凸优化问题的6个标准测试函数,所提算法在质量和资源消耗上均表现更好;对于二相编码雷达波形优化,证实了使用所提算法优化波形是可行和有效的。  相似文献   

11.
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   

12.
IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…  相似文献   

13.
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   

14.
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   

15.
A doping system consisting of NPB and PVK is employed as a composite hole transporting layer (CHTL). By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK : NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK : NPB at 1:3.  相似文献   

16.
An insert layer structure organic electroluminescent device(OLED) based on a new luminescent material (Zn(salen)) is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn(salen)/Liq/LiF/A1/CuPc/NPD/Zn(salen)/Liq/LiF/A1. Effective insert electrode layers comprising LiF(1nm)/Al(5 nm) are used as a single semitransparent mirror, and bilayer cathode LiF(1 nm)/A1(100 nm) is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.  相似文献   

17.
Due to variable symbol length of digital pulse interval modulation(DPIM), it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation(FDPIM) method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.  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.
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   

20.
High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET > PDMAT > TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.  相似文献   

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