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81.
提出了一种基于中国地面数字电视广播传输标准的星座映射与解映射器的设计方法.使用DSP Builder的各种模块搭建系统,并利用Signal Compiler生成HDL工程.在完成对所生成工程的优化后,进行相关软硬件仿真验证.实现了32QAM、16QAM星座映射器与解映射器的设计、仿真,并在利用DSP Builder进行DSP系统开发方面进行了深入的探索.  相似文献   
82.
通过对多核应用技术进行系统效率与任务属性关系的优化分析.得出系统所接受任务的不同属性与对应的系统效率之间的指令级仿真结果,证明了系统面向的任务属性与选择的多核系统性能存在科学的性价比,从而保证了期望的系统计算力与整体架构之间符合原本的科学性与经济性.  相似文献   
83.
While the experimental detection of entanglement provides already quite a difficult task, experimental quantification of entanglement is even more challenging, and has not yet been studied thoroughly. In this paper we discuss several issues concerning bounds on concurrence measurable collectively on copies of a given quantum state. Firstly, we concentrate on the recent bound on concurrence by (Mintert and Buchleitner in Phys Rev Lett 98:140505/1–140505/4, 2007). Relating it to the reduction criterion for separability we provide yet another proof of the bound and point out some possibilities following from the proof which could lead to improvement of the bound. Then, relating concurrence to the generalized robustness of entanglement, we provide a method allowing for construction of lower bounds on concurrence from any positive map (not only the reduction one). All these quantities can be measured as mean values of some two-copy observables. In this sense the method generalizes the Mintert–Buchleitner bound and recovers it when the reduction map is used. As a particular case we investigate the bound obtained from the transposition map. Interestingly, comparison with MB bound performed on the class of ${4\otimes 4}While the experimental detection of entanglement provides already quite a difficult task, experimental quantification of entanglement is even more challenging, and has not yet been studied thoroughly. In this paper we discuss several issues concerning bounds on concurrence measurable collectively on copies of a given quantum state. Firstly, we concentrate on the recent bound on concurrence by (Mintert and Buchleitner in Phys Rev Lett 98:140505/1–140505/4, 2007). Relating it to the reduction criterion for separability we provide yet another proof of the bound and point out some possibilities following from the proof which could lead to improvement of the bound. Then, relating concurrence to the generalized robustness of entanglement, we provide a method allowing for construction of lower bounds on concurrence from any positive map (not only the reduction one). All these quantities can be measured as mean values of some two-copy observables. In this sense the method generalizes the Mintert–Buchleitner bound and recovers it when the reduction map is used. As a particular case we investigate the bound obtained from the transposition map. Interestingly, comparison with MB bound performed on the class of 4?4{4\otimes 4} rotationally invariant states shows that the new bound is positive in regions in which the MB bound gives zero. Finally, we provide measurable upper bounds on the whole class of concurrences.  相似文献   
84.
In order to reveal the relationship between system time domain model parameters and system frequency response functions, new magnitude bounds of frequency response functions for nonlinear Volterra systems described by NARX model are established. The magnitude bound of the nth-order generalized frequency response function (GFRF) can be expressed as a simple n-degree polynomial function of the magnitude of the first order GFRF, whose coefficients are functions of the model parameters and frequency variables. Thus the system output spectrum can also be bounded by a polynomial function of the magnitude of the first order GFRF. These results demonstrate explicitly the analytical relationship between model parameters and system frequency response functions, and provide a significant insight into the magnitude based analysis and synthesis of nonlinear systems in the frequency domain.  相似文献   
85.
基于混沌免疫进化算法的聚类算法分析   总被引:1,自引:0,他引:1  
结合免疫进化算法和混沌优化算法各自在数据空间搜索的优势,本文提出了一种新的基于混沌免疫进化算法的模糊c_均值聚类算法.该算法实现了从全局到局部的两层领域搜索机制,且仿真结果表明,该算法有效地避免了通常聚类方法易出现的早熟现象,同时也具有较快的收敛速度和较高的准确度.  相似文献   
86.
Organic solar cells (OSCs) have achieved much progress with rapidly increasing power conversion efficiencies (PCEs). It should be noted that the top-performance OSCs are generally consisted of active materials with complex chemical structures, resulting in high costs. Here, combining the material design and morphology control, high-efficiency OSCs are fabricated by a low-cost donor: acceptor blend. A completely non-fused electron acceptor named Tz is designed and synthesized via introducing thiazole units on both sides of a bithiophene core, which shows an outstanding PCE of 13.3% with a typical polythiophene donor. More importantly, optimization guidelines are presented to get excellent morphology for low-cost donor:acceptor systems. Three polythiophenes are selected, poly(3-hexylthiophene) and its two derivatives with electron-withdrawing substitutions (PDCBT and PDCBT-2F), as donors to fabricate the cell devices. The computational and experimental data reveal that decreasing the electrostatic interaction between polythiophene and Tz is the key to getting a suppressed miscibility and thus a high phase purity. This study provides insight into the molecular design and donor:acceptor matching requirements for high-efficiency and low-cost OSCs.  相似文献   
87.
88.
田园  马孜  李爱国 《控制工程》2011,18(2):283-285
针对大孔径管件的圆度误差问题,研制了一套在线检测系统,并提出了一种分组粒子群优化算法的圆度误差评定,将整个搜索空间分成若干个小组,各个小组单独搜索,迭代到一定步数,将各个小组混合,重新合成一个大的种群,在整个空间追随各自的极值和种群的最优值,避免了陷入局部最优解.在自行研制的检测系统中进行了应用,证明分组粒子群优化方法...  相似文献   
89.
90.
基于FPGA+DDS的信号源设计与实现   总被引:1,自引:0,他引:1  
采用DDS+FPGA+DAC数字信号激励器硬件电路和数字波形合成软件算法设计实现了宽带信号源所需要的各类信号,覆盖30 MHz~1 GHz频段,功率达到20 W.在完成了具体的设计和实验后实现了样机的制作,通过现场测试验证了其完全满足应用需求.  相似文献   
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