基于低压电力线的音频传输系统设计

通过分析低压电力线信道模型，结合美国Intellon公司的电力线MAC／PHY／AFE集成收发器INT5200的主要功能和结构特点，详细阐述以TMS320VC5471为主控单元，以电力载波芯片INT5200为核心的音频传输系统，给出音频信号的采集及其在低压电力线上通信的硬件设计和软件设计。     

配电载波技术在配网自动化系统中的应用

介绍了配电载波和电力线载波的区别以及配电载波的技术难点和技术优势，并从多方面讨论了配电载波技术在配网自动化中的应用。     

电力线载波通信系统存在的问题及解决方案

电力线载波是电力系统特有的、基本的通信方式，电力线载波通信是指利用已有的电力网，通过载波调制方式将模拟或数字信号进行高速传输的技术。分析了电力线通信的通道特性及其干扰，并结合电力通信的特点提出了解决办法。     

电力线载波通讯技术在远程自动抄表系统中的应用

系统、全面地介绍了电力线载波通讯技术的特点、应用及发展状况,并对目前的电力线载波通讯芯片进行了比较;同时、也提出了电力线载波通讯技术运用在远程自动抄表系统中的应用方案。     

一种基于直接序列扩频通讯的电力载波采集器

采用直接序列扩频通讯技术设计了一种电力线载波抄表系统,介绍了基于该技术的电力线载波抄表器,给出了电力线扩频通讯单元的设计.着重介绍了低压电力线载波通讯中的同步系统,并分析了同步过程的2个阶段搜捕阶段和跟踪阶段.此外,给出了该系统采集器部分软件设计流程图.     

电力线载波通讯中载波频率的研究

本文分析了电力线载波中的衰减特性和干扰特性，以及它们与载波频率的关系，给出了确定载波频率的理论依据，为如何提高电力线载波的通讯距离提供了一种思路。     

利用电力线实现载波遥控的研究

介绍了利用电力线的载波原理，具体应用于遥控领域，实现了利用电力线传播遥控信号，研制了电力线载波遥控开关，广泛应用于电力设备及照明控制等领域。     

X10及PLCBUS在智能家居网络中的应用与分析

从电力线载波类、无线射频类、总线类三种按传输介质分类的协议,分析智能家居网络技术,重点阐述分析了电力线载波类的x10协议、PLCBUS协议以及两协议在智能家居网络中的应用,认为基于电力线载波技术组成智能家居控制网络具有广阔的发展前景。     

电力线扩频载波通信电路的设计

设计一个基于SSCP300的电力线扩频载波的通信电路。根据chirps扫描频率进行载波的扩频通讯技术和CEBus总线的有关协议进行电路设计。给出了符合CEBus标准，以SSCP300为接口控制器件的电力线扩频载波通信部分电路原理图，经仿真实验收到了预期效果。     

扩频技术在电力通信中的应用

阐述了扩展频谱技术的基本原理和特点，并设计了实际电力线直扩载波系统方案。基于直接序列扩频技术的电力线通信具有良好的抗干扰性和保密性，通过实验和证明该方案是可行有效的。     

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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