基于Modbus协议的配电室环境监测系统设计

针对配电网自动化系统中配电室的监测问题, 采用有线监测的方式难以实现室内环境监测, 基于射频技术的无线监测方式是有效的方法. 设计一种基于Modbus协议的配电室环境监测系统, 该系统由无线数据收发模块, 无线传感器测量模块, 集中器模块构成. 详细介绍了各模块的工作原理、硬件设计和软件设计. 实际应用表明所设计的配电室环境监测系统实现了配电室内环境的实时无线远程监测, 并具有响应快、精度高以及可靠性强的特点.     

基于现场总线的配电监测系统研制

介绍了基于RS485现场总线的对现有铁路配电室进行的计算机监测系统改造设计。工控机和智能采集终端通过RS485总线组成的可靠系统可完成配电室各种电参数及开关设备、保护设备的数据和状态显示、故障报警、历史参数记录等功能。     

矿井勘探钻孔多参量监测系统设计

为了有效的对矿井勘探钻孔数据进行长期监测,设计了一套地勘钻孔实时监测系统.系统以STM32F103RCT6为主控芯片,采用LoRa低功耗传输网络为通信方式,上位机软件采用Python程序设计,实现实时数据的监测和存储.其中系统监测上位机软件能够实现包括用户登录和管理、串口参数设置、数据实时显示、数据存储、显示当前时间及蓄电池电压、表格打印等功能.试验结果表明,矿井勘探钻孔多参量监测系统可扩展性强,运行稳定,能够满足对矿井勘探钻孔多参量监测的需求,具有较好的应用前景.     

电能量损失监控系统的研究与应用

从分析用户的非法用电情况入手,设计了一种新的电能量监测系统,并详细介绍了它的工作机理.该系统采用DSP技术、通讯技术和数据库技术,能够及时反映出用户的用电情况并对非法用电进行及时补偿,具有实时性、可靠性和实用性等特点.     

智能发电设备电参量测量仪的研制

发电设备电参量是反应发电设备状况的重要参数,为此研制了基于嵌入式系统的智能发电设备电参量测量仪.通过加Hanning窗的基2 FFT电参量计算方法、硬件频率检测跟踪方法降低泄漏效应和栅栏效应;同时设计了外部总线接口的高速同步AD转换、多路反馈(MFB)型滤波器,多任务调度,以及图形开发软件μC/GUI的应用,提高了电参量测量的实时性、抗干扰能力和人机交互能力.实验测试表明,该系统精度不大于0.5%,稳定性好,使用操作方便.     

集中供热微机远程监测系统及其应用

介绍了一种热力管网多点实时监测系统的工作原理和硬件组成 .本系统采用了有线传输方案 ,可对集中供热换热站及热用户的温度、压力、流量及热量等参数进行测量并集中监测 .     

HDM型直流接地绝缘监测仪

HDM型直流接地绝缘监测仪,采用磁调制原理对支路接地产生的漏电流进行直接测量,传感器与被测支路只有磁的联系,没有电的联系,成功克服了采用直流检测装置外加信号方案对直流系统运行的影响,防止了误报、虚报现象.该监测仪具有母线电压监测,异常报警等功能,能够实现多电压等级下多支路检测,可根据用户要求实现远程通讯功能,便于实现变电站运行无人值班.系统分布电容对测量无影响.     

基于CS5460A的三相电参数检测仪的设计

针对现有电参数检测仪功能单一、自动化程度不高等缺点,采用ATMEGA162为微控制器、专用电能计量芯片CS5460A为模数转换器.根据嵌入式系统的设计思想设计了三相电参数检测系统.介绍了三相电参数检测仪的硬件结构和软件设计方法,并分析了提高测试精度的方法.测试表明,系统的测量精度可达到0.1级,能满足对设备用电参数监测的要求.     

基于ARM的电能质量监测控制器的研制

介绍了一种基于ARM的电能质量监测控制器的研制过程.该硬件主要由电压电流信号采集模块、LCD液晶显示部分、以太网接口模块GSM无线通信模块和USB移动存储模块组成.软件部分主要对电参量的算法进行了推导,给出了优化算法,操作系统选用源码公开的实时操作系统μC/OS-Ⅱ.其核心代码短小精悍,具有可移植性、可裁剪、占先式等优点,通过实时多任务操作系统对所有任务的调度管理,解决在单任务系统中难以处理的实时性差的问题,同时增强了系统工作的可靠性.对电能质量参数进行了实验测试和分析,结果表明这种设计符合电能质量监测标准.     

基于GSM的电能量监测系统的研究与应用

针对用户的非法用电情况,设计了一种新的基于GSM的电能量监测系统,并详细介绍了它的工作机理。该系统采用微处理器技术、GSM通讯技术和数据库技术,能够及时反映出用户的用电情况并对非法用电进行及时补偿,具有实时性、可靠性和实用性等特点。     

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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