基于声卡的RLC电路稳态特性(相频部分)采集系统

介绍了基于声卡的RLC电路稳态特性(相频部分)采集系统.系统以Delphi作为开发平台,声卡为数据采集卡,调用Windows标准API函数编程而成.主要包括数据实时采集、波形实时显示、数据分析处理、结果显示、采集数据保存和数据回放.实验结果表明系统是成功的.     

基于串行总线的井下多通道高速高精度数据采集系统的设计

设计了一种八通道高速高精度并行数据采集系统.该系统具有14位分辨率,4×105次/s最高转换速度.采用复杂可编程逻辑器件(CPLD)实现了数据采集速率和采集数据量的程控选择功能,并控制FIFO缓存波形数据.数字处理器(DSP)通过串行命令总线控制采集速率、采集深度并启动采集;通过串行高速数据总线读取采集数据并进行实时处理.整个电路控制灵活,指标先进,结构紧凑,适合高性能井下设备使用.井下测试结果表明,波形特征明显,信噪比高.     

基于串行总线的井下多通道高速高精度数据采集系统的设计

设计了一种八通道高速高精度并行数据采集系统.该系统具有14位分辨率,4×105次/s最高转换速度.采用复杂可编程逻辑器件(CPLD)实现了数据采集速率和采集数据量的程控选择功能,并控制FIFO缓存波形数据.数字处理器(DSP)通过串行命令总线控制采集速率、采集深度并启动采集;通过串行高速数据总线读取采集数据并进行实时处理.整个电路控制灵活,指标先进,结构紧凑,适合高性能井下设备使用.井下测试结果表明,波形特征明显,信噪比高.     

微电脑控制的心电数据床边采集系统

介绍的微电脑控制的心电数据床边采集系统，具有心电数据的采集、存储和向计算机传送数据的功能。它与传统的心电数据采集系统相比，着重解决以下关键技术：以51系列单片机为核心的软、硬件结构；具有12位分辨率的多通道A／D采样、多路选择功能的高性能前置放大电路；实时高效的数据压缩算法等。系统性能稳定、使用方便，非常适用于心电数据的床边采集。     

基于LabVIEW的虚拟示波器的设计与实现

本文选用LabVIEW图形化编程语言为开发软件,采用AC1810作为外用数据采集卡,开发虚拟实验仪器:虚拟示波器.虚拟示波器主要功能是对采集到的数据进行触发、时基控制后,完成对输入信号的电压、频率和周期等参数的测量,同时,利用FFT窗口对波形进行频谱分析,可以实现单、双通道显示波形,并可以对波形运算后进行输出,并显示测量值.     

基于嵌入式系统的心电无线远程传输系统

研制了一套适用于远程急救或家庭远程监护的基于嵌入式处理器Intel SA-1110的心电无线远程传输系统．该系统硬件部分由数据采集模块、数据存储及显示模块、GPRS模块及嵌入式微处理器Intel SA-1110组成．数据采集模块负责心电的采集、滤波及A／D变换；数据存储和显示模块完成心电数据的存储、波形显示；GPRS模块实现心电信号的无线远程传输；Intel SA-1110控制全系统及各模块间的通讯；软件部分包括基于嵌入式操作系统WinCE开发的病人管理程序和基于Windows开发的远端心电服务器软件．在1天内5个不同时段进行数据传输实验，比较采集的心电信号与远程服务器接收的信号，误码率为零，传输速度为12．5～35kb／s．     

基于STM32的便携式心电信号采集系统设计

设计了一套便携式、高精度的小型实时心电信号采集显示系统.采用STM32作为核心控制器,选用TI公司的ADS1298模拟前端IC芯片,二者构成系统的数据采集部分. ADS1298采集的信号通过SPI通信发送到控制器,然后利用蓝牙模块将数据发送到由LabVIEW搭建的上位机显示平台,最后进行数据处理,显示心电波形图.实验结果表明:该系统能够实现人体心电信号的高精度(μV/bit)、便携式采集,并能实时动态显示波形;利用现有的高效滤波算法EMD对所采集数据进行处理,结果显示EMD的滤波效果与本文模型基本一致.     

基于单片机的多路数据采集系统的设计与实现

本数据采集系统是基于单片机AT89S52为控制核心的数据采集系统,该数据采集系统具有电路简单、功耗低、可靠性高等优点,能实现对多路模拟通道信号的数据采集与处理,并将采集的数据送LED显示器显示等功能.另外,该系统可作信号发生器使用产生频率为1kHz的方波测试信号.     

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。     

利用USB接口实现数据采集

研究了USB接口的数据采集系统的设计与实现。整个系统以EZ-USB控制器为核心,由EZ-USB经控制电路实现对模数转换的控制。数据缓冲器存满后,通知EZ-USB控制器,由主机取出采样数据,并实时显示波形。系统硬件主要采用以AN2131QC为核心的USB接口电路和以模数转换器AD1674为核心的USB设备功能单元电路,系统软件采用Ke il C51语言编写芯片固件程序、采用VC 语言编写USB设备驱动程序和W in32应用程序。实验表明,该系统用于音频等信号的数据采集,性能稳定,效果良好。     

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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