微粒群算法优化设计宽带微带天线

微粒群（PSO）算法具有概念简单、容易实现及收敛速度快等优点,离散二进制PSO是PSO在二进制空间的扩展。将离散二进制PSO算法与FDTD法相结合来优化设计宽频带微带天线,以矩形微带贴片天线为例,仿真结果显示,在将PSO算法中的微粒维数分别设置为20维和64维的情形下,通过对天线贴片形状的优化,天线的-10dB带宽由原来的4．4％左右拓宽至大约13．8％和14．5％,优化成效显著。     

基于多项式滤波的高性能内插器的ASIC设计

提出了一种设计基于多项式滤波的高性能内插器的有效方法.偏移二进制编码的并串DA算法和折叠技术使滤波和多项式计算仅用一个乘法器完成;存储器资源比同等并行度的DA算法降低50%.在0.13μm工艺下,利用该方法实现了时钟频率为300 MHz,最高插值倍数为256的内插滤波器.总结了该方法与传统多相分解实现相比在资源消耗、灵活性等方面的优势.     

网络图像检索重排序系统建模和仿真

基于关键词的网络图像检索得到的结果往往是海量且无序的,给用户造成不便。本文构建了一个网络图像检索结果重排序系统并进行了仿真。提出了一种利用图像SIFT局部特征构建图像间视觉Graph结构对图像进行聚类的重排序算法,并引入检索关键词的网络翻译以提高检索效率。仿真结果证明,系统的重排序结果满足网络用户的检索期望,验证了算法的有效性。     

无线定位中的接收信号强度值匹配算法

提出两种在WLAN环境下利用RSSI值与距离之间关系进行定位的匹配算法。分别对两种算法的原理进行理论分析,建立算法实现的模型,使之在不同情况下都能够精确地计算匹配结果。提出实现算法的基本流程,并对算法本身的特点进行了理论分析。分析表明通过该方法的修正可以明显改善定位的精度。     

LDPC码在量子密钥分配多维协商算法中的应用

密钥协商是量子密钥分配(QKD)的重要环节,影响着QKD的密钥率和安全距离.作为一种低信噪比时较为高效的密钥协商方案,多维协商算法被很好地应用在高斯调制连续变量QKD中,延长了通信距离.本文研究了二进制LDPC码在多维协商算法中的应用方案,进而扩展到多进制LDPC码.仿真表明,相比二进制LDPC码,利用多进制LDPC码能够使多维协商性能获得明显增益.     

On the rigidity theorems for lagrangian translating solitons in pseudo-Euclidean space I

Let f be a smooth strictly convex solution of
defined on a domain Ω C R^n, where ai, bi and c are constants. Then the graph Mvf of △f is a spacelike translating soliton for mean curvature flow in pseudo-Euclidean space with the translating vector（al, a2, . ., an; bz, b2, , bn）. In this paper, we will use alCfine technique to show a Berustein Theorem： if the graph Mvf is complete, then f（x） must be a quadratic polynomial and Mvf is an ailine n-plane.     

Binary-component micelle and vesicle:Free energy and asymmetric distributions of amphiphiles between vesicle monolayers

The real-space two-dimensional self-consistent field theory(SCFT) is employed to study the free energies of micelles and vesicles constituted by binary amphiphilic diblock copolymer AB in homopolymer A.With an increasing volume fraction of copolymer AB,there are morphological transitions from circle micelles to oblate circle-like micelles,to a compound structure with inverted micelles in the inner center and micelles outer layer,and to vesicles.Special attention is paid to the role of the copolymer AB in controlling the free energies of the micelles and vesicles by examining the effect of the length ratio of A/B with the fixed whole chain length of the AB copolymer,the length effect of A or B block with the corresponding fixed length of B or A block,for one component of copolymer,and the effect of different amphiphile compositions for a binary-component copolymer system.The quantity η is provided to describe the asymmetric density distribution of amphiphiles between the inner and outer monolayers of vesicles,and to quantify the relative asymmetric extent of the density distribution between two species of copolymers in binary component vesicles.     

Transport dynamics of an interacting binary Bose Einstein condensate in an incommensurate optical lattice

We investigate the transport dynamics of an interacting binary Bose-Einstein condensate in an incommensurate optical lattice and predict a novel splitting of a matter wavepacket induced by disorder potential and inter-species interaction. The effect of atomic interaction on the dynamics of the mobile and localized atoms are also studied in detail. We also discuss the behavior of the balanced and inbalanced mixtures in the incommensurate optical lattice.     

一类伪随机二进制数列的碰撞与雪崩效应

设p为奇素数,f(x)∈F_p[x].设a与p互素,表示a关于模p的逆,即1≤≤p-1且a≡1 mod p.定义二进制数列E_(p-1)=(e_1,…,e_(p-1)),其中e_n={(+1),(-1)如果0≤R_p(f(n)+■)

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