图像扫描波动性定量标准及分形扫描矩阵的快速生成

在图像扫描技术中，首要的问题是如何尽量减小生成数据的波动性。本文在深入研究各种扫描技术的基础上，定义了一种描述扫描产生数据波动性的度量指标，基于图像存在局部连续性，证明了Hilbert分形曲线扫描优于其他传统扫描，表明在生成数据的最佳连续特性，并通过实验 分析了图像扫描方式对DCT变换编码效果的影响。最后，给出了一个构造Hilbert扫描矩阵的快速算法。     

Colored timed Petri nets for modeling and analysis of cluser tools

In this paper, a colored timed resource‐oriented Petri net (CTROPN) is developed to model the cluster tools in semiconductor fabrication. It is structurally simple and concise, since each module in a cluster tool corresponds to a unique place in CTROPN. It is also powerful in modeling the qualitative and temporal behavior of the cluster tools with a single‐blade or dual‐blade robot. The initial transient behavior, steady‐state behavior and the final transient behavior can all be investigated through a single model. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society     

THEORETICAL ANALYSIS OF COORDINATES MEASUREMENT BY FLEXIBLE 3D MEASURING SYSTEM

The system mathematical model of flexible 3D measuring system is built by theoretical analysis,and the theoretical formula for measuring space point coordinate is also derived. Frog-jumping based coordinate transform method is put forward in order to solve measuring problem for large size parts. The frog-jumping method is discussed,and the coordinate transform mathematical model is method of the space point coordinate compared to original value,and an advanced method is provided. Form the space point coordinate transform formula can derive the calculation measuring method for measuring large size parts.     

A signal theory approach to the space and frequency variant filtering performed by the human visual system

A mathematical representation is given of the processing performed by the peripheral nervous cells of the human visual system. This representation consists essentially of a set of shift-variant convolutions, implying non-uniform resolutions in both the space and frequency domains. A remarkable property of such “convolutions” is the form-invariance of their outputs with respect to (size) linear scalings of the inputs. It is shown that this latter property is a necessary support of the hypothesis according to which the visual system translates linear scalings of the (retinal) inputs into shifts of the (cortical) outputs.     

用小波矩阵分析法进行函数的分解与重构

就傅氏级数和小波变换之间的关系进行较全面地讨论。并采用小波矩阵分析方法,使小波变换本质跃然于纸上。同时给出小波分解和小波重构的计算公式,应用变得十分容易。     

基于预测编码与DCT变换编码的比较

深入分析了预测编码与DCT变换编码的异同点，并从编码增益、块效应系数、预测与变换与变换前后的能量关系等多方面比较了两种编码的优缺点。     

Blind 2-D Angles of Arrival Estimation for Distributed Signals Using L-Shaped Arrays

Most existing two dimensional（2-D）angles of arrival（AOAs）estimation methods are based on the assumption that the signal sources are point sources.However,in mobile communications,local scattering in the vicinity of the mobile results in angular spreading as seen from a base station antenna array.In this paper,we consider the problem of estimating the 2-D AOAs of spatially distributed sources.First we perform blind estimation of the steering vectors by exploiting joint diagonalization,then the 2-D AOAs are obtained through two fast Fourier transforming of the estimated steering vectors.Simulations are carried out to illustrate the performance of the method.     

应用于信号处理的Fourier变换与小波变换

在分析Fourier变换与小波变换异同点的基础上,对它们在不同类型信号的处理过程中的应用进行了探讨．并给出一个检测故障点的仿真实例,证明了小波变换的优越性．     

基于新的整型9/7小波变换的硬件设计

提出了基于新的整型9/7小波变换的硬件设计方案.整个系统采用流水结构,充分利用硬件存储资源,实现了行列变换的并行处理.同时把常系数乘法优化为较少次数的移位加操作,加快了运算速度,缩小了电路规模.采用VHDL语言对系统进行描述并在Quartus Ⅱ 5.0环境下仿真,经验证满足图像实时处理的要求,为后续实时压缩编码和传输提供了有利条件.