基于LabVIEW的电能质量监测实验平台设计

构建了基于NI公司PCI-6024E数据采集卡、BNC-2120接线盒和Lab VIEW软件的电能质量监测实验平台,设计了硬件系统和软件系统,借助于Lab VIEW强大的数据计算能力和图形化显示功能,运用快速傅里叶变换、对称分量法等算法实现了对电能质量各项参数的分析计算。本实验平台既可以加载Lab VIEW软件生成的模拟信号,也可以加载实际电网信号,实验结果表明:该平台测量准确度高、计算速度快、结构可靠、实用性强。     

在LabVIEW下基于调用DLL的压缩机气缸压力信号的采集

为实现活塞往复压缩机气缸内压力信号的采集,研究了Lab VIEW调用外部代码的方法,即库函数节点CLF调用外部的动态链接库和代码接口节点CIN调用C源代码,介绍了在虚拟仪器软件开发平台Lab VIEW上调用动态链接库的技巧及过程,实现了具有DMA直接内存访问功能的数据采集模块USB20D的通信。实践证明,基于动态链接库的Lab VIEW数据采集系统简单易行,运行效率高,使Lab VIEW强大的图形化编程和数据处理功能与非NI公司的数据采集设备结合而进行数据采集。     

基于LabVIEW的涡轮增压器试验台测控系统的设计

利用NI公司的Lab VIEW开发环境,并结合PCI-6238数据采集卡开发一个数据采集与处理平台,用于实现涡轮增压器试验台的数据采集、处理、显示以及数据保存等功能.该系统具有简洁、友好的人机界面,可成功完成实验过程.     

基于ZigBee及LabVIEW的无线医疗监测系统设计

设计并实现了一个基于Zig Bee无线通信及Lab VIEW软件的远程医疗健康监测系统,可实现用户端血压、脉搏、体温三种典型生理参数的实时远程监测及健康报警.系统本地节点采用STM32小型嵌入式控制器实现传感器信号的采集与处理,再通过Zig Bee无线通信网络将生理信息传给PC服务器端.PC服务器端采用Lab VIEW编程控制串口通信,实现生理信息的实时监测及GSM短信报警.测试结果表明,生理参数测量结果基本准确,系统运行稳定.     

基于labview钢绳芯胶带检测系统设计

为了满足钢绳芯胶带运行中对信号采集分析的要求,设计了一个基于PCI总线的数据采集系统.在阵列传感器数据的基础上,采用labview软件和NI公司M系列PCI-6224数据采集卡,设计了一个多通道、高速、同步数据采集系统.首次实现了利用labview处理胶带检测的数据,高精度、实时地显示检测结果,并将其数据可视化显示.     

基于声卡的数据采集系统

采用虚拟仪器的思想,设计了一种基于声卡的数据采集系统。该采集系统在Lab VIEW程序开发环境下,能够实现声音信号的采集、播放和识别等功能。实验结果表明:系统能够正确采集声音频率范围内的信号,可用于该范围内的一般数据采集与应用。     

基于虚拟仪器的混频生物阻抗测量系统

为获得同一时刻、不同频率下的生物阻抗信息,设计了基于虚拟仪器的混频生物阻抗测量系统.该系统硬件平台由自主开发的信号源模块和信号调理模块以及NI公司的PCI-6111板卡组成.对混频激励下阻抗信息的提取方法进行了研究,提出了基于虚参考点的数据采集方法,利用LabVIEW实现数据的采集、分析处理、显示和存储等,大大提高了开发效率.通过与Agilent4294A阻抗分析仪进行比对,证明该系统具有较高的测量精度和准确性.     

基于LabVIEW的35kV变电站噪声监测系统设计

该文基于虚拟仪器工程平台(Lab VIEW)设计了35k V变电站噪声监测系统。采用多个声强和声压传感器提取变电站噪声信号,通过USB数据采集卡采样后送入Lab VIEW编写的软件进行处理。噪声监测软件具有实时声功率、波形显示、峰值计算、功率谱分析和历史数据管理等功能。该系统具有简单有效,能直观显示监测结果,且易于控制的优点。     

融合机器视觉的液位控制实验系统设计

将机器视觉技术与传统的过程控制系统深度融合,在水槽液位控制系统基础上增加摄像头、数据采集卡、上位机,结合NI视觉开发模块建立视觉液位测量及控制实验系统。介绍了实验系统的构成,视觉开发模块NI Vision Assistant的功能,以及视觉液位测量过程中图像采集、摄像头标定、图像处理、液位高度提取的方法;设计基于Lab VIEW的PID控制算法,并对实验结果和数据进行分析。视觉液位检测具有较高的精度,扩充了教学内容,推进了新技术在实验教学中的应用。     

基于USB接口的虚拟示波器的设计

在详细地讨论虚拟仪器系统的功能特点的基础上,给出了虚拟仪器系统构建所需要的硬件及软件技术,介绍了一种以USB控制器为接口的实现Lab VIEW虚拟仪器和PC之间的高速USB通信的虚拟示波器设计方法。设计给出了在Lab VIEW环境下测试软件的设计思想,以及利用Lab VIEW软件的模块化编程以及多线程技术框架,实现了多种常见周期信号及任意指定信号的多通道输出。     

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