NSCT域红外图像改进非局部均值滤波算法

结合非下采样轮廓波变换(NSCT),提出了一种红外图像改进非局部均值滤波算法(Improved Non-local Means Filtering,INLMF)。该算法首先对红外噪声图像进行多尺度NSCT变换,其次分别从相似图像块自适应划分方法以及滤波权重计算方法 2个方面对经典非局部均值滤波算法进行适当改进,将改进后的非局部均值滤波算法(INLMF)应用于处理高频分解系数,然后将滤波后的高频分解系数与低频分解系数进行重构,得到去噪后的图像,最后对去噪后图像采用非负支撑域有限递归逆滤波(Non-negativity and Support Constraints Recursive Inverse Filtering,NAS-RIF)算法进行图像复原,以尽可能消除因滤波造成的图像失真。测试结果表明,本文算法滤波效果优于NLMF及其已有的改进算法。     

基于聚类稀疏表示与图像块自适应聚合的单幅图像超分辨研究

A Single Image Super-Resolution (SISR) reconstruction method that uses clustered sparse representation and adaptive patch aggregation is proposed. First, we randomly extract image patch pairs from the training images, and divide these patch pairs into dif-ferent groups by K-means clustering. Then, we learn an over-complete sub-dictionary pair offline from corresponding group patch pairs. For a given low-resolution patch, we adap-tively select one sub-dictionary to reconstruct the high resolution patch online. In addition, non-local self-similarity and steering kernel regression constraints are integrated into patch aggregation to improve the quality of the re-covered images. Experiments show that the proposed method is able to realize state-of-the-art performance in terms of both objective evaluation and visual perception.     

Quantum theory analysis of the action micromechanism exerted on bioparticles from laser microbeams

The effect of laser microbeam trapping the bioparticles has been appfied widely in the biology .However the micromechanism of the acting that realizes the laser-microbeam trapping bioparticles is still lacking. In this paper ,the act microchenism of the gradiant force of laser microbeam for the bioparticles is analysed by means of quantum theory ,The result accords with our experiment.     

Convergence rate of spherical harmonic expansions of smooth functions

We extend a well-known result of Bonami and Clerc on the almost everywhere (a.e.) convergence of Cesàro means of spherical harmonic expansions. For smooth functions measured in terms of φ-derivatives on the unit sphere, we obtained the sharp a.e. convergence rate of Cesàro means of their spherical harmonic expansions.     

向径函数上的球面平均及其点态收敛性

设球面平均函数为,则当f∈LP(Rn)是向径函数, n≥3,1≤P≤n/n-1时,几乎处处成立.     

基于防火墙和VPN技术的网络安全架构研究与应用

随着网络信息资源的增长,网络规模的不断扩大,网络系统的安全问题日趋严重。本文基于防火墙和VPN技术研究了企业网络系统的安全解决方案,方案可以满足一个大中型跨地区企业的安全需求;同时,还给出了一个典型的应用示例。     

射频识别系统的攻防策略分析

随着大规模集成电路技术的进步以及生产规模的不断扩大，RFID产品的成本将不断降低，RFID应用也将越来越广泛。由于在最初的RFID应用设计和开发过程中，没有考虑安全问题，导致目前安全问题日益凸显。这已经成为制约RFID应用的重要因素。本文重点讨论了目前攻击者采用的主要攻击手段，以及应对这些攻击的防御策略。     

Fixed-width confidence intervals for contrasts in the means

The sequential procedure developed by Bhargava and Srivastava (1973, J. Roy. Statist. Soc. Ser. B, 35, 147–152) to construct fixed-width confidence intervals for contrasts in the means is further analyzed. Second-order approximations for the first two moments of the stopping time and the coverage probability associated with the sequential procedure, are obtained. A lower bound for the number of additional observations after stopping is derived, which ensures the mxact probability of coverage. Moreover, two-stage, three-stage and modified sequential procedures are proposed for the same estimation problem. Relative advantages and disadvantages of these sampling schemes are discussed and their properties are studied.     

A general class of inequalities with mixed means

Suppose (T, Σ, μ) is a space with positive measure,f: ? → ? is a strictly monotone continuous function, and &;(T) is the set of real μ-measurable functions onT. Letx(·) ∈ &;(T) andf ○x)(·) ∈L ₁(T,μ). Comparison theorems are proved for the means $\mathfrak{M}_{(T,{\mathbf{ }}\mu ,{\mathbf{ }}f)} (x( \cdot ))$ and the mixed means $\mathfrak{M}_{(T_1 ,{\mathbf{ }}\mu _1 ,{\mathbf{ }}f_1 )} (\mathfrak{M}_{(T_2 ,{\mathbf{ }}\mu _2 ,{\mathbf{ }}f_2 )} (x( \cdot )))$ these inequalities imply analogs and generalizations of some classical inequalities, namely those of Hölder, Minkowski, Bellman, Pearson, Godunova and Levin, Steffensen, Marshall and Olkin, and others. These results are a continuation of the author's studies.     

基于低秩分解和改进的非局部平均的SAR图像相干斑抑制

为抑制合成孔径雷达（SAR）图像成像过程中形成的相干斑噪声,提出了一种基于低秩分解和改进的非局部平均的SAR图像相干斑去噪方法。首先将SAR图像进行对数处理,将乘性噪声转换为加性噪声;然后利用低秩稀疏分解将对数图像分解成低秩图像部分和稀疏图像部分;接着对含噪严重的稀疏图像部分分析其结构张量,生成非局部平均滤波所需的衰减因子,进行改进的非局部平均滤波去噪;最后再做图像合成,经指数变换得到去噪后的SAR图像。实验结果表明,该方法经视觉评价、边缘保持指数（EPI）和等效视数（ENL）等方面评测,具有较好的抑制噪声和保持边缘及纹理细节的能力。