关于SVD水印算法的分析和探究

基于奇异值分解理论的数字水印技术是一种新的值得探讨和研究的变换域水印技术,它的提出为数字水印技术的发展开拓了新的思路和方法.本文对传统的基于奇异值分解理论的数字水印技术进行了深入分析和研究,并提出了改进方法,给出了一种新的基于奇异值分解的数字水印方案.仿真实验证明,新的方法比较好的满足了数字水印的透明性和鲁棒性,能经受住通常的图像处理操作且具有较大的应用潜力.     

基于SVD和ICA的全息水印算法

基于奇异值分解和独立分量分析,提出一种新的数字全息水印算法。该算法利用全息图的特点,采用数字全息图代替普通的二值图像作为水印图像,提高了水印算法的安全性。奇异值分解被应用于水印的嵌入过程中以提高水印算法抗几何攻击能力,并借助于独立分量分析实现全息水印图像的盲提取。实验结果表明,该算法能有效地抵抗JPEG 压缩、加噪、声滤波和对比度增强等常规攻击,同时,对旋转、平移、翻转和缩放等几何攻击也具有一定的鲁棒性。     

UKF算法与SVDKF算法性能的比较

在模式识别领域,基于Unscented的卡尔曼滤波算法（UKF）广受关注,但在求解过程中经常会遇到病态问题,从而影响算法的性能。基于奇异值分解（SVD）的卡尔曼滤波算法（SVDKF）以SVD代替Cholesky分解协方差矩阵产生sigma样本点,可以提高协方差矩阵的数值稳定性。通过对两种算法性能进行仿真比较发现,SVDKF算法优于UKF算法,具有良好的鲁棒性,能有效改善滤波性能,提高算法的精度。     

A simplified MMSE-based iterative receiver for MIMO systems

A simplified minimum mean square error （MMSE） detector is proposed for joint detection and decoding of multiple-input multiple-output （MIMO） systems. The matrix inversion lemma and the singular value decomposition （SVD） of the channel matrix are used to simplify the computation of the coefficient of the MMSE filter. Compared to the original MMSE detector, the proposed detector has a much lower computational complexity with only a marginal performance loss. The proposed detector can also be applied to MIMO systems with high order modulations.     

线性流形上矩阵方程AXA~T=B的双反对称解

利用矩阵对的商的奇异值分解研究了线性流形上矩阵方程AXA^T=B双反对称解．     

基于计算机生成全息图及SVD—DWT的数字水印算法

提出一种基于奇异值分解和离散小波变换并应用计算机生成全息图作为水印图像的新算法．该算法结合了奇异值分解抗几何攻击能力强以及离散小波变换抗噪声、压缩等能力强的特点．实验表明,该算法能有效地抵抗旋转、平移、翻转和缩放等几何攻击,同时对滤波、加噪声、JPEG压缩、图像模糊、裁剪、锐化和对比度增强等常规攻击也有很强的鲁棒性．     

基于SVD和直方图的JPEG同幅图像篡改盲检测算法

首先分析了基于小波变换和奇异值分解方法对同幅图像拼接篡改检测的缺点,结合相关重要的思想,构建了一种改进算法,该算法运用SVD提取图像块特征,并采用偏移频率的直方图来确定阈值。在仿真实验中,通过运用三种算法对图像篡改进行检测,对比结果表明,文章所提算法对同幅图像单次篡改和多次篡改均有更好的检测效果,而且通过修改图像的质量因子的实验进一步证实了该算法具有一定的鲁棒性。     

Mobility and equilibrium stability analysis of pin-jointed mechanisms with equilibrium matrix SVD

Under certain load pattern, the geometrically indeterminate pin-jointed mechanisms will present certain shapes to keep static equalization. This paper proposes a matrix-based method to determine the mobility and equilibrium stability of mechanisms according to the effects of the external loads. The first and second variations of the potential energy function of mechanisms under conservative force field are analyzed. Based on the singular value decomposition (SVD) method, a new crite- rion for the mobility and equilibrium stability of mechanisms can be concluded by analyzing the equilibrium matrix. The mobility and stability of mechanisms can be classified by unified matrix formulae. A number of examples are given to demonstrate the proposed criterion. In the end, criteria are summarized in a table.     

SVD-LSSVM and its application in chemical pattern classification

INTRODUCTION Pattern classification is an important problem in the machine learning field and least squares support vector machine (LSSVM) proposed by Suykens is an easy and powerful tool for this problem (Suykens and Vandewalle, 1999a). Only a set of linear equations should be solved during training of an LSSVM, which makes it easy to be realized. LSSVM is based on structural risk minimization (SRM) rule, which en- hances its generalization ability. SRM rule requires that model …     

基于潜在语义空间的文本检索问题研究

本文针对潜在语义空间模型下文本检索存在的问题进行了研究；对LSI／SVD方法的理论及问题进行探讨，对文本一特征项矩阵加权方式进行了改进，对文本的聚类提出了k—means截尾算法，对原始向量空间降秩后的语义空间维数的确定提出了解决方法。