基于LabVIEW平台的激光吸收光谱测量系统

为利用计算机系统迅速高效地实现测试和分析功能,研究了基于虚拟仪器软件LabVIEW的多通道激光吸收光谱数据采集与处理系统。该系统以LabVIEW为软件开发平台,以便携式计算机、数据采集卡NI USB-6212和光电探测器为硬件基础,通过在LabVIEW程序中调用Matlab数值计算程序实现激光频率的实时刻度分析;通过中值滤波和计算平均方法提高测量光谱信噪比;采用模块化技术和多线程技术实现数据流运行机制,确保获得较高精度和较全面的吸收光谱数据。结果表明:该系统能够实现气体吸收光谱信号的实时采集、显示、存储和分析,并能获得光谱吸收分析结果。     

基于LabVIEW的超声分子束激光光谱仪控制系统设计

文章阐述了超声分子束激光光谱仪的结构特点,介绍了在LabVIEW平台上结合RS-232接口和PXI总线技术进行仪器控制和数据采集的设计方法.在现有实验环境下,开发了基于LabVIEW的超声分子束激光光谱仪控制系统,实现了设备控制和光谱数据采集软件自动化.     

基于LabVIEW与单片机串口的信号处理的研究

介绍了一种利用单片机采集数据，LabVIEW作为开发平台，二者之间通过串口实现数据通信的数据采集系统，利用LabVIEW的图形环境进行频谱分析。通过对Matlab的功能调用，对信号进行了滤噪处理。     

基于LabVIEW的电弧焊工艺参数采集系统的设计开发

针对电弧焊工艺的虚拟测试仪器,以LabVIEW为基础开发电弧焊工艺参数的数据采集系统。该软件系统包括数据采集软件和数据回放软件,可以对数据进行采集、读取和回放,从而实现对信号的分析和处理。同时可以与测试系统硬件进行通讯,完成对所采集参数的实时显示和存储。对所设计数据采集系统进行调试及实测,结果表明此系统可以准确地对电弧焊过程的电流和电压信号进行采集。     

基于LabVIEW和MATLAB的语音信号采集系统设计

充分利用LabVIEW的简洁和可靠,通过声卡设计LabVIEW语音信号采集与声音信息保存系统.借助MATLAB强大的数据计算能力,对采集的语音信号进行消噪处理,实现LabVIEW和MATLAB的优势互补.本设计简洁易用且处理效率高,是对语音信号进行分析处理的一条有效途径.     

基于LabVIEW的汽车平顺性试验系统设计

本设计采用LabVIEW编程软件,开发了一套汽车平顺性试验系统。根据实验室现有设备,利用三轴式加速度传感器,采集汽车行驶时的加速度信号,通过数据采集卡将所获的模拟信号输入电脑。使用图形化虚拟编程软件LabVIEW进行编程,对所采集的信号数据进行处理,根据计算出的相应的平顺性评价指标和相关的评价标准,对汽车的行驶平顺性的好坏进行评价。通过试验系统的硬件设计、软件开发和试验验证,实现了汽车平顺性的测试功能,并可对悬架系统设计等方面作进一步研究。     

基于最小二乘的MEVVA源产生的金属镍等离子发射谱线的单峰拟合

在MEVVA源产生金属等离子体的发射光谱诊断的过程中,需要用＂Plasus Specline＂光谱分析软件对光谱仪采集到的等离子体发射光谱数据进行标定.但是受光谱仪分辨率的限制,某些谱线虽然有较高的谱线强度,但是标定结果与实际情况不符或者是由于不存在明确的峰值波长而不能准确标定.为解决这个问题,本文根据最小二乘法的函数逼近原理,结合原子发射光谱的多普勒展宽和洛伦兹展宽机制,在只考虑一种展宽机制的前提下,分别用高斯线型和洛伦兹线型两种轮廓函数对以上2种谱线进行函数逼近,即对光谱仪采集到的发射光谱数据点进行单峰拟合.用逼近函数的中心波长作为该谱线的波长并用分析软件对其进行标定,从而实现用＂Plasus Specline＂软件对光谱仪采集光谱信号中每一条谱线的准确标定.在函数逼近的过程中,分别采用改进后的牛顿迭代法、变量轮换法和模式搜索法3种优化方法求解逼近函数,并对这3种方法的优化效果进行比较.     

基于LabVIEW数据采集系统

虚拟仪器技术在仪器领域显示了强大的生命力.介绍了虚拟仪器领域中最具有代表性的图形化编程开发平台LabVIEW,并对LabVIEW驱动普通数据采集卡进行了研究.总结了调用LabVIEW的端口操作图标、利用CIN图标调用C语言驱动程序及动态数据交换(DDE)技术实现LabVIEW驱动普通数据采集卡的方法.针对双诺AC6010卡,成功地实现了可供LabVIEW直接调用的动态库的编制与调用.开发出了一套性价比较高的数据采集系统.     

C8051F020单片机远程升级方法在光谱仪中的应用研究

为了解决光谱仪内部数据库及程序的固件更新的需求,提出了一种基于C8051F020单片机的远程固件升级方法,并完成系统的软硬件设计。该系统在光谱分析仪中,实现了光谱信号的采集分析;同时可以将数据通过网络进行数据的传输。因此利用其具有远程通信的特点,实现了利用网络进行远程在线更新系统固件的方式。实际应用证明该方式简便有效,系统运行稳定。     

基于声卡的水射流反射声信号采集处理系统

为了能够用较低的成本实现高压水射流冲击不同几何尺寸靶物时反射声音信号特征值的有效提取,采用基于LabVIEW和声卡的高压水射流反射声信号采集处理系统实现技术。通过对LabVIEW软件编程结合声卡和高精度传声器实现了水射流反射声信号的实时采集,应用MATLAB编制小波降噪和模极大值提取程序,通过调用MATLAB Script实现LabVIEW与MATLAB的通信,完成信号的降噪和有用成分的分离与提取。实验结果验证,本系统能实现实时有效地提取对应不同靶物几何参数的特征值。     

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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