基于电网多通道数据采集系统

本文提出了一种基于电网信号的高速,多通道同步采集的数据获得系统,以MAX125作为核心的模数转换器件,以TMS320LF2407A作为数据处理的核心,并且围绕两者精心设计了外围电路,通过地址译码使DSP通过外部I/O方式方便的对AD进行操作。     

一种新型温度检测系统设计

MAX6 6 75是Maxim公司推出的具有冷端补偿的单片K型热电偶放大器与数字转换器。文中介绍了该器件的特点、工作原理及接口时序 ,并给出了与单片机的接口电路     

一种调幅红外无线耳机的设计

采用MAX1726与MAX9722器件,通过幅度调制方式,实现一款红外无线耳机.该红外无线耳机具有供电方式多样、方向性好、音量可调节等功能.给出了详细设计原理与硬件实现.     

使用MAX＋PLUS II进行数字电路模拟仿真时常见问题与解决方法

MAX＋PLUSII是altera公司推出的第三代开发工具软件,该软件提供了灵活、高效的界面,设计者无需精通器件内部的复杂结构,只需用自己熟悉的设计输入工具（原理图、波形图和硬件描述语言等）进行设计输入,MAX＋PLUSII将这些设计转换成目标结构所要求的格式,从而使设计者能够轻松掌握和使用MAX＋PLUSII软件。     

用高密度可编程逻辑器件实现参数化FIR滤波器

从提高FIR滤波器的处理速度出发，在传统结构的基础上导出减少乘、加次数的优化结构，并利用FLEX器件系列中的查找表LUT结构构成向量乘、加运算，提高滤波器的工作速度并节省器件资源。最后，利用Altera公司的MAX PLUSII软件进行了并、串FIR滤波器的逻辑设计，达到了硬件实现参数化FIR滤波器的目的。     

CDMA手机卷积码编码器的设计与FPGA的实现

阐述了卷积编码的原理和CDMA手机卷积码编码器。在MAX PLUS2软件平台上,给出了利用现场可编程门阵列器件设计的卷积码编码器电路,并进行了编译和波形仿真。综合后下载到可编程器件EPF10K10LC84-3中,测试结果表明,达到了预期的设计要求。     

基于CPLD的循环码编码器的设计

介绍了循环码编码的基本原理,并以MAX+PLUSⅡ软件为开发平台,利用CPLD器件设计了一个(7、3)循环码编码器,该编码器具有编码快速、准确率高等特点.     

微机USB和RS485通讯接口的软硬件设计

文章使用最新的器件CP2101桥接器作为核心,加上UART和RS485的转换芯片MAX1483和一些附加电路IC实现了USB和RS485转换器的硬件电路,介绍了作为USB和UART桥接器的新器件CP2101的功能和用法,设计了在微机平台上与转换器进行通讯的软件.     

基于FPGA的交织编码器的设计

阐述了交织编码的原理,在MAX+PLUS2的EDA软件平台上,给出了利用现场可编程门阵列器件的逻辑单元,用移位寄存器设计交织编码器的原理和电路,进行了编译和波形仿真实验.     

MAX7219在串行LED显示驱动器上的应用

MAX7219是一个采用3线串行接口的8位共阴极7段LED显示驱动器.本文分析了MAX7219各个寄存器的功能,并结合MAX7219的工作时序,给出了MAX7219在8031单片机系统中的一个应用实例.     

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     

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

正~~     

Brief Introduction to “Journal of Jilin University( Science Edition) ”

<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has