基于CPLD与单片机的控制系统设计

结合CPLD与单片机设计了一种数据采集控制系统。A／D转换采用ADC0808芯片,转换精度为8位;方位采集通道为水平方向和俯仰方向,具有错误报警、焦距调节等功能,数据采集具备良好的实时性。该系统实现简单,可靠性好,具有很强的可移植性,可广泛用于全方位、高精度数据采集系统的实现。     

多通道高速数据采集电路设计

在高速数据采集系统中 ,多通道高速数据采集电路设计是一个难点。本文以一种典型的多通道高速数据采集电路设计为例 ,详细说明多通道高速数据采集、转换、存储技术及具体实现方式     

多通道高速数据采集电路设计

在高速数据采集系统中,多通道高速数据采集电路设计是一个难点。本文以一种典型的多通道高速数据采集电路设计为例,详细说明多通道高速数据采集、转换、存储技术及具体实现方式。     

汽轮机无线热力特性测试系统设计

以汽轮机热力特性数据的无线采集为设计方向,设计并实现了一种基于无线射频单片机nRF9E5的新型无线数据采集系统,该系统具有低功耗和抗干扰性能,能够满足火电厂数据采集的要求。     

基于LabVIEW的多通道振动测试与分析系统

为利用计算机系统迅速高效地实现测试与分析功能,研究了一种基于虚拟仪器软件LabVIEW的多通道振动测试与分析系统。该系统中,专门设计的外置式数据采集箱具有多通道输入信号调理,内、外触发采样控制,A/D转换和先入先出(FIFO)缓存等功能;采用增强型并口(EPP)实现计算机与外置数据采集模块的高速数据传输。结果表明,该系统具有较高精度,并能实现振动信号的采样、存盘、分析和回放功能。     

基于FPGA的高速数据采集器

介绍了一种基于FPGA的高速数据采集器,给出了系统方案设计,并对系统各部分电路设计进行了详细介绍。对高速数据采集系统中串并转换功能的实现方法进行了详细阐述。该高速数据采集器由于采用了FPGA+DSP平台设计,使得该系统具有较强的通用性和应用价值。     

带浮点放大器的CPLD数据采集系统设计

采用浮点放大器和CPLD设计了多通道数据采集系统.其浮点放大器根据输入信号范围,放大适当的倍数,保证了数据采集系统的动态测量范围;CPLD具有丰富的内部资源和大量I/O管脚,处理速度快,可实现灵活多变的控制流程;双端口RAM作为A/D转换与CPU之间的桥梁,为高速数据吞吐提供了有力的硬件支持;结合以上几方面的优势,系统总体上实现了高速、高精度数据采集.     

基于C8051F020的心电测量系统设计

为研制一种能够在临床上使用的心电测量系统,以C8051F020单片机为采集控制中心,运用模拟信号采集和数字信号处理技术,实现心电信号的采集。完成了心电测量系统的设计,该系统具有实现各种控制、数据采集和A/D转换等功能。实验结果本系统运行稳定可靠,满足了临床准确采集心电信号的需要。     

基于USB接口的数据采集系统设计

ARM2378为数据采集系统的控制核心,系统中还包括信号数据采集电路、电源电路和报警电路等。设备与PC主机能够实现USB接口通讯,并能够进行数据的采集、转换、存储、异常报警等。便于系统的维护与升级,提高了开发效率,开发周期也被大大缩短。     

基于USB2.0的脑电信号采集系统设计

提出了脑电信号采集系统的硬件与软件设计框架,设计了脑电数据的提取、过滤、去除干扰、三级放大、A/D转换及USB接口等电路.使用KeilC51、Visual C++以及Windows2000DDK编程工具开发了USB固件程序、设备驱动程序.该系统实现了脑电数据的准确采集、高速传输和实时处理,解决了传统脑电数据采集系统方案的缺陷.设计符合下一代数据采集技术的发展方向,满足实际需要.     

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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