利用小波变换技术求解钢筋混凝土框架地震反应

基于离散正交小波变换的快速Mallat算法,用紧支集正交小波db6对地震动加速度时程进行了分解,随后将该分解结果用于求解多自由度弹性体系的地震反应。通过实例计算,发现小波变换法的计算结果与用振型分解法计算的结果较接近,说明该方法用于地震反应分析是可行的。     

离散超小波变换下双正交小波正交程度的研究

利用离散超小波变换作为工具,证明了任何一个双正交小波变换的谱不可能分布在1附近的某个区间内,并给出了该区间的一个估计,所给的结果说明双正交小波不可能无限接近一个相应的正交变换. 同时用实验印证了,在其它条件相同的情况下,谱半径越小,双正交小波变换的性能越好.     

基于离散小波变换与小波包分解的语音增强算法

提出了一种基于离散小波变换（DWT）和小波包分解（WPD）的语音增强算法.该算法首先将带噪语音进行离散小波变换,并分别对离散逼近信号和离散细节信号采用不同的基小波进行小波包分解,再按照不同的规则选取阈值进行去噪,最后对去噪后的语音信号完成重构.计算机仿真表明,在计算量相当的情况下,该算法优于离散小波变换法去噪和小波包分解法去噪.     

两通道滤波器组和离散序列的小波变换

多抽样率滤波器组理论和离散时间序列的小波变换有着密切关系.笔者从信号处理的角度研究了离散时间序列的小波变换利用树状滤波器组实现的方法,分析了两通道共轭正交镜象滤波器组理论及滤波器设计,离散时间序列的正交小波变换的快速实现以及正交小波的构造,指出了其内在联系,最后举例说明了正交小波变换通过共轭正交镜象滤波器组来实现信号分解和重构的全过程.     

动态载荷识别的小波正交算子变换法

在动态载荷识别动力学方程中引入离散正交小波 (即Haar小波正交基 ) ,从而得到了一种新的动态载荷识别方法小波正交算子变换法 .此方法对高阶模态信息能有效地提取 ,克服了傅立叶变换的缺点 ,从而提高了动态载荷的识别精度 .用一简单质量弹簧系统验证了本方法的正确性     

正交小波变换的残余相关分析

构造了正交小波变换矩阵，分析了平稳模型和非平稳模型下正交小波变换的残余相关特性．实验结果表明，对于非平稳信号，正交小波变换的去相关性能好于离散余弦变换；而对平稳信号，正交小波变换性能较差，因此，在数据压缩应用中，应使用正交小波变换与其它经典变换相结合的编码方法     

由小波滤波器系数求尺度函数和小波函数

为更好地将离散小波变换和连续小波变换联系起来,在分析了现有的由小波滤波器积法求尺度函数和小波函数的方法的基础上,提出了对迭代卷积法的一种改进算法,同时给出了迭代卷积法的收敛判定方法,并分析了改进后算法的优势.实验结果表明该算法是有效的.     

基于离散小波变换的数字图像隐藏技术

基于离散小波变换(DWT)和S盒算法给出了一种数字图像加密算法.首先分别对秘密图像和公开图像应用离散余弦变换和离散小波变换,并对秘密图像的离散余弦变换系数进行S盒变换,进而潜入到公开图像的小波系数中,利用逆变换得到结果图像.实验证明该方法可行、效果好、隐藏信息量大,隐藏算法还能抵抗许多攻击,并具有一定的安全性和鲁棒性.     

由最优双正交小波变换矩阵决定的小波基

通过双正交小波变换矩阵的特征值分析给出了一个新的定义-最优双正交小波变换矩阵.实验验证了在相同的小波族中,由最优双正交小波变换矩阵决定的双正交(超)小波是"最优"小波.因此,在9-7小波族中,最优9-7小波在图像压缩的性能要优于常用的CDF97小波.     

正交小波变换的残余相应分析

构造了正交小波变换矩阵，分析了平稳模型和非平衡模型上正交小波变换的残余相关特性。实验结果表明，对于非平稳信号，正交小波变换的去相关性能好于离散余弦变换，而对平稳信号，正交小波变换性能较差，因此，在数据压缩应用中，应使用正交小流变换与其它经典变换相结合的编码方法 。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with