数字散斑相关方法在实验力学中的适用性

数字散斑相关方法是近些年来新兴的一门利用图像处理技术来计算物体的位移及变形的方法,具有全场测量、非接触、光路相对简单、测量视场可以调节、不需要光学干涉条纹处理、可适用的测试对象范围广、对测量环境无特别要求等优点,对此利用3个基本的实验,刚体平动、橡胶材料拉伸、三点弯梁实验,验证了数字散斑相关方法在大位移及变形测量中的适用性.     

非接触法测量炮弹外径技术研究

非接触测量是以光电、电磁等技术为基础,在不接触被测物体表面的情况下,得到物体表面参数信息的测量方法。典型的非接触测量方法如激光三角法、电涡流法、超声测量法、机器视觉测量法等等。     

利用电子散斑干涉法测量金属表面的位移场

建立了电子散斑干涉测量的专用光路,对金属试件进行了典型的离面位移测量,经过数字图像处理,获得了该试件在一定压力下产生的水平及垂直方向上离面位移的分布曲线.此技术具有全场、非接触、高精度、高灵敏度、不避光、不需要特殊防震、快速实时可在线测量等优点,已经成为全息散斑计量学中最具有实际应用价值的技术.     

机械振动的激光测量研究

提出一种测量机械振动的方法,具有光路简单、抗环境干扰、非接触、实时测量的特点。用２Ｄ－ＣＣＤ接收振动物体表面的散射光强,通过计算机辅助系统自动处理,并给出振动物体的拓动参数。     

基于FPGA的激光双焦点互相关测速系统

采用常规的机械接触式测量方法,不能满足移动物体表面的特殊状态要求.基于FPGA的激光双焦点互相关测速系统,融合了信号采集与处理、高速逻辑器件FPGA和互相关技术,在各种运动物体的非接触测速上具有高速、高精度的特点,可应用于非接触式固体表面的测量.     

基于SOPC的钢轨断面高速测量系统

随着我国高速铁路的快速发展,对钢轨断面高速检测技术的需求变得越来越迫切.本文以三角形摄影测量原理和片上可编程(SOPC)技术为基础,利用亚像素图像处理算法、NIOS Ⅱ处理器和以太网接口等IP软核技术,实时采集和并行处理钢轨图像,实现了多路钢轨断面的高速高精度在线测量.文中论述了基于SOPC与PC协同的高速高精度图像处理系统设计,并给出了系统原型机的试验验证.     

应用Matlab图像处理技术的位相物体的位相测量

组建了一种实用的测量相位物体相位的系统,主要介绍其系统结构、基于LabView平台的硬件组件的连接、软件部分的图像处理算法的设计,并将其应用于位相光栅相位的定量检测.实验结果表明:该测量系统结构简单、重复性好、稳定性高、数据采集自动化,能较好的再现位相光栅的结构,并得到相位光栅相位分布假彩色图、灰度图及三维分布图.对相位物体的相位以及其它光学参数如厚度、折射率的测量具有一定的应用价值.     

厚度测量及厚度分选仪

研制了一种非接触厚度测量及厚度分选仪，其传感器由气动位移传感器和变压器式位移传感器复合而成，该系统不受被测对象水分、灰度及密度的影响，具有较高的测量精度，为非接触厚度测量提供了新手段．     

基于空间载波调制散斑干涉的低频振动测量技术

提出一种基于空间载波调制的散斑干涉测振技术,将散斑干涉测量技术、同态滤波图像处理技术和连续图像采集技术等结合在一起,对物体的微位移低频振动的振幅、周期、频率等参数进行测量,绘制相应的振动曲线,并开发了相应的数据处理系统.实验表明,该方法可实现全场非接触动态测量、精度较高,具有较好的实际应用前景.     

摄影测量与遥感发展探讨

摄影测量与遥感是从摄影影像和其他非接触传感器系统获取所研究物体,主要是获取地球及其环境的可靠信息,并对其进行记录、量测、分析与应用表达的科学和技术,随着计算机技术、空间技术的迅猛发展,摄影测量与遥感之间的距离越来越小,它们的应用己深入到经济建设、社会发展、国家安全和人民生活等各个方面。     

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     

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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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