基于虚拟仪器的导航雷达回波信号采集器设计与实现

信号采集的目的是了后续雷达成像和海浪信息提取。基于虚拟仪器技术,对单脉冲体制导航雷达设计了一套数据采集系统。以计算机和PXI-9820数据采集卡为硬件,以VC++6.0软件作为开发平台,构建了基于Windows平台的数据采集系统,雷达回波信号采集单元采用多路信号同步采集的设计方案,并指出了系统实现过程中的多通道同步采集的关键技术问题。东海某海域的岸基采样实验证明了基于虚拟仪器技术的数据采集器设计的可行性及系统运行的可靠性。     

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ARM嵌入式平台的雷达数据采集系统

针对雷达接口信号测试复杂问题,提出了基于ARM9系列嵌入式平台作为硬件开发平台的雷达数据采集系统。将采集系统按照便携式数据采集系统和数据管理及分析系统两大分系统进行了详细阐述。     

基于LabVIEW的温度测试系统

介绍了基于虚拟仪器技术设计的温度测试系统。将高性能的数据采集卡PCI-1711与传感元件和调理电路于一体,构建成了温度测试硬件系统,软件基于Labview虚拟仪器开发平台,采用模块化设计,实现了检测信号的实时采集、数据处理、数据显示等功能。系统可应用于实验教学中。     

基于虚拟仪器的机床切削力采集与数据处理系统

利用国产数据采集设备和虚拟仪器技术开发了机床切削力数据采集与处理系统,该系统可以具有信号采集.数据处理、存储以及图形显示等功能.     

人体脉搏检测的软件模块设计

通过HK-2000C集成化数字脉搏传感器结合虚拟仪器软件LabVIEW设计开发脉搏分析仪模块,构建出了虚拟人体脉搏采集系统,实现了虚拟仪器界面中脉搏信号的采集、存储、回放和处理,可应用于中医脉诊教学及实验.     

便携式压力变送器检定系统的设计

基于虚拟仪器技术,设计了便携式的压力变送器检定系统。该系统以高精度智能压力表为标准表,以LabView为软件平台,通过计算机完成压力变送器的信号采集与转换,并与标准表进行对比。整个系统具有信号采集、误差计算、报表打印等功能,且携带方便,操作简单,可大大提高工作效率。     

基于虚拟仪器LabVIEW的发动机台架试验数据采集系统设计

发动机台架试验系统是测试发动机动力性、经济性、可靠性的必要手段,其自动化水平与测试精度能够直接影响试验数据采集及分析处理的准确性。基于虚拟仪器LabVIEW设计了发动机台架试验数据采集系统,硬件部分主要包括实现发动机转速、温度、振动等信息获取的传感器,以及匹配传感器的信号调理模块和数据采集卡;软件部分是基于虚拟仪器LabVIEW编写的数据处理与界面显示程序。调试运行结果表明构建的发动机台架试验数据采集系统能够实现发动机转速特性、负荷特性、振动等信息的准确采集并能在界面窗口直观显示,能够满足发动机性能测试过程中运转特性参数信息准确获取的需求。     

基于LabVIEW的信号处理系统

介绍了以图形化编程语言LabVIEW为软件开发平台,通过数据采集卡和PC为硬件支撑,构建信号的采集和分析的虚拟仪器系统,该系统不仅实现了实时波形显示、电压有效值、信号频率等参数的计算,还将虚拟仪器技术运用到频谱分析中来,增强了仪器的功能,缩短了仪器的开发时间。     

基于LabVIEW的信号处理系统

介绍了以图形化编程语言LabVIEW为软件开发平台,通过数据采集卡和PC为硬件支撑,构建信号的采集和分析的虚拟仪器系统,该系统不仅实现了实时波形显示、电压有效值、信号频率等参数的计算,还将虚拟仪器技术运用到频谱分析中来,增强了仪器的功能,缩短了仪器的开发时间。     

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.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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