P—对称等带宽带状方程组的改进平方根法

本文将改进平方根法拓广到求解Ｐ－对称等带宽带状方程组，并给出相应的矩阵压缩存储方法及ＦＯＲＴＲＡＮ过程描述。     

基于序列图象对应概率累积的基础矩阵求解方法*

提出一种基于图象序列对应概率累积的基础矩阵求解算法.该算法基于序列对应概率累积求最大熵点的对应概率累积分布图,采用RANSAC思想和加权最小二乘法拟合极线,通过统计分类器求解极点并消除出格极线,并利用所求的对应极线和极点,采用一种参量化方法求解F矩阵.该算法工程实现容易,对输入的源图象没有苛刻的要求,可以基于随机拍摄的图象序列方便地求解F矩阵.     

激光径向偏振光栅反射镜的研究

径向偏振光是近些年引起广泛关注的一种新型偏振光,它在粒子操控、金属切割和提高显微镜分辨率方面具有广阔的应用前景。径向偏振光可以通过在激光器谐振腔内应用径向偏振光栅反射镜来获得。首先在顶层刻蚀光栅反射镜的模型上通过自编程序分析光栅反射镜各参数对光栅性能的影响,然后设计出光栅反射镜复合结构并结合微纳加工工艺进行了可行性分析。     

Quantum Fisher Information for Density Matrices with Arbitrary Ranks

We provide a new expression of the quantum Fisher information （QFI） for a general system. Utilizing this expression, the QFI for a non-full rank density matrix is only determined by its support. This expression can bring convenience for an infinite-dimensional density matrix with a finite support. Besides, a matrix representation of the QFI is also given.     

Further studies on stability analysis of nonlinear Roesser-type two-dimensional systems

This paper is concerned with further relaxations of the stability analysis of nonlinear Roesser-type two-dimensional （2D） systems in the Takagi-Sugeno fuzzy form. To achieve the goal, a novel slack matrix variable technique, which is homogenous polynomially parameter-dependent on the normalized fuzzy weighting functions with arbitrary degree, is developed and the algebraic properties of the normalized fuzzy weighting functions are collected into a set of augmented matrices. Consequently, more information about the normalized fuzzy weighting functions is involved and the relaxation quality of the stability analysis is significantly improved. Moreover, the obtained result is formulated in the form of linear matrix inequalities, which can be easily solved via standard numerical software. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed result.     

基于操作腔外原子比特控制腔内原子比特相干性时间演化

考虑初始处于两类Bell态的两原子比特,将其中一个注入真空态腔中发生共振相互作用的情况,研究基于操作腔外原子比特控制腔内原子比特相干性时间演化.考察对腔外原子比特施Hadamard(H)门,H类门,Y门及位相门四种逻辑门操作及态选择测量前后,腔内原子比特约化密度矩阵非对角元时间演化曲线,讨论两类Bell态之间的关联性.结果表明,对腔外原子比特操作前,腔内原子比特密度矩阵非对角元在任意时刻都为零,总是处于混合态或经典态,因此始终退相干.而对腔外原子比特施H门和H类门操作及基态测量后,腔内原子比特密度矩阵非对角元呈现周期为2π的时间演化,除(2n+1)π/2时刻外,其相干性得到恢复;在nπ时刻,其最大相干叠加态和一般相干叠加态被制备;两类Bell态之间存在R∧(π/2)旋转关联性.而对腔外原子比特施Y门及位相门操作后,腔内原子比特的相干性得不到恢复.发现腔内原子比特的相干性得到恢复的必要条件是,逻辑门操作能够调节腔内原子比特与环境的相互作用,并使两原子比特与场分离的同时,它们之间形成强相干性的纠缠态分布.     

基于现场可编程门阵列单探测器复合轴控制技术

为了解决空间激光通信系统中单探测器复合轴结构的粗精解耦难题,通过分析二维关联控制矩阵,得出粗精跟踪解耦的必要条件,提出了一种单探测器复合轴结构的工作方式.在跟踪过程中,相机直接配合子轴执行器完成精跟踪工作,而主轴的跟踪信息由子轴的角度偏转器来提供,同时所有的图像处理算法、位置检测算法、以及粗精伺服控制算法都在现场可编程门阵列中实现,完成了系统的轻小型化设计.实验搭建了测试系统,并对现场可编程门阵列硬件和系统跟踪性能进行测试,结果表明单探测器复合控制系统可以实现跟踪准确度优于3μrad,为工程化奠定了良好的基础.     

基于改进梯度投影NMF和复Contourlet变换的遥感图像融合

为了尽可能地保留全色图像的空间信息和多光谱图像的光谱信息,提出了一种基于改进梯度投影非负矩阵分解和复Contourlet变换的遥感图像融合方法.首先,以多光谱图像的强度分量图像为标准,对全色图像做直方图匹配,得到新的全色图像;然后,利用复Contourlet变换分别分解多光谱图像的强度分量图像和新的全色图像,得到各自对应的低频分量和高频分量;接着,对两幅低频分量图像采用改进梯度投影的非负矩阵分解作为融合规则获取新的低频分量,并对两幅高频分量图像使用系数绝对值较大法获取新的高频分量;最后,通过逆复Contourlet变换和逆色调-饱和度-强度变换获得融合后的图像.大量实验结果表明,与HSI方法、NMF与无下采样Contourlet变换结合的方法以及提升小波变换与HSI结合的方法相比,本文方法获得的融合图像具有更高的空间分辨率和更多的光谱信息.     

Spectral analysis of the UFBG-based acousto optical modulator in V–I transmission matrix formalism

In this study, the V-I transmission matrix formalism （V-I method） is proposed to analyze the spectrum characteristics of the uniform fiber Bragg grating （FBG）-based acousto--opfic modulators （UFBG-AOM）. The simulation results demon- strate that both the amplitude of the acoustically induced strain and the frequency of the acoustic wave （AW） have an effect on the spectrum. Additionally, the wavelength spacing between the primary reflectivity peak and the secondary reflectivity peak is proportional to the acoustic frequency with the ratio 0.1425 nm/MHz. Meanwhile, we compare the amount of calculation. For the FBG whose period is M, the calculation of the V-I method is 4 × （2M-l） in addition/subtraction, 8 × （2M - 1） in multiply/division and 2M in exponent arithmetic, which is almost a quarter of the multi-film method and transfer matrix （TM） method. The detailed analysis indicates that, compared with the conventional multi-film method and transfer matrix （TM） method, the V-I method is faster and less complex.