一种高精度水力压裂电位监测系统的设计

水力压裂技术起源于石油和天然气的增产,现已发展成为页岩气开采过程中一种有效的方法。设计了一种高精度电位监测系统,对页岩气开采水力压裂过程中地表电位的变化进行动态监测。该系统由24位ADC LTC2400与内嵌CAN控制器的主控芯片STM32F105构成高精度数据采集单元,并用16位DAC进行自然电位补偿,实现了对压裂电位的高精度采集和可靠传输。系统设计完成后进行了多项室内测试及室外测试。测试结果表明,系统实现了高精度、小型化、低功耗设计和便携式应用。     

嵌入式智能高压断路器状态监测系统的研究与设计

针对高压断路器机械特性监测的具体要求,研究和设计了一种基于DSP和μC/OS-Ⅱ的嵌入式智能高压断路器状态监测系统。该系统的数据采集层由多种传感器和DSP数据处理器构成,在移植到DSP芯片的μC/OS-Ⅱ实时操作系统平台上开发应用软件,完成对高压断路器机械特性的多个参数的采集、处理与显示,同时通过CAN总线将数据传送到监测服务器,服务器上管理软件采用VC++工具开发,主要完成对测量数据的存储、显示和分析处理等。多次实验测试结果表明,智能监测系统性能稳定,准确性较高,效果理想。     

CAN总线技术及其在船舶结构安全监测系统中的应用

提出基于CAN总线与Windows CE.NET嵌入式操作系统来建立船舶结构安全监测系统.重点论述了数据采集模块硬件接口设计及硬件抗干扰措施的设计.此外,描述了Windos CE.NET下的CAN卡驱动程序的设计要点.实验证明基于CAN总线的船舶结构安全监测系统在网络拓扑结构上架构简单、可扩展性强、运行可靠、对节点请求响应实时性强的特点,能够满足实验室测试和船舶航行中对船舶结构应变变化的监测要求.     

汽车局域网CAN总线在客车上的应用研究

研究汽车局域网CAN总线在现代客车上的具体应用 ,采用 89C5 2单片机与SJA1 0 0 0CAN控制节点为核心设计了基于CAN总线的客车后置发动机数据采集显示系统 ,系统利用单片机通过传感器对发动机的冷却水温、机油压力、转速、车速等信号进行采集 ,再用CAN总线传输所有信号 ,简化了汽车线束 文中还给出了数据采集发送软件框图和数据接收显示软件框图 系统在实验室的模拟强干扰下 ,工作稳定可靠     

基于CAN总线通信技术的家庭空气监测系统的设计与制作

<正>本文介绍了基于CAN总线通信技术的家庭空气监测系统的设计与制作。该系统通过使用CAN总线通信技术,实时监测家庭的空气质量,并提供报警功能以确保居民的健康和安全。本文详细讨论了传感器选型、数据采集与处理、CAN总线通信协议的实现以及云平台的连接等关键设计与制作步骤。     

基于CAN总线冗余结构的矿下智能语音系统设计

为了满足矿下恶劣环境中智能语音通信系统高可靠性的需求,提出将冗余结构思想应用到CAN总线智能语音通信系统。系统在平行双CAN总线为干线前提下,各级节点均以双CAN总线进行通信。节点以STM32微处理器和AMBE-2000芯片为核心,语音信号经过AMBE编码后由CAN总线传送到系统各节点,同时传感器采集井下参数也经CAN总线传送至地面主站,实现地面主站与井下分站及分站之间的实时语音通信以及对井下状况的监测与预警。实验结果表明,在突发事件下,这种冗余结构在矿下抗干扰能力强,针对矿下语音通信、数据采集,体现出了系统良好的可靠性和实时性,达到了预期的效果。     

基于DSP技术与USB2.0的数据采集实时处理系统

数据采集与实时处理技术广泛应用于雷达、通信、遥测遥感、海洋监测等领域,主要介绍一种基于DSP和USB2.0技术的双通道数据采集与实时处理系统设计方案,该方案采用TMS320C6713B作为核心处理芯片,CY7C68013为USB2.0接口芯片,给出了多通道采集系统的硬件设计及软件编程方法。     

煤岩应力动态监测系统的设计

分析了现有煤矿监测系统的现状,提出利用CAN总线进行分布式的煤岩应力动态监测,给出了系统设计的性能要求,详细介绍了系统的硬件设计过程.系统结合高精度数据采集技术和先进的CAN现场总线技术,实现了分布式煤岩应力的高精度实时动态监测.     

基于ARM的煤矿安全监控系统通信分站的设计

针对煤矿安全的重要性,设计了一种基于ARM7控制器的煤矿安全监控通信分站;该分站由传感器数据采集电路、集成CAN控制器的ARM7芯片、CAN接口电路组成;用移植入μC/OS-Ⅱ实时操作系统的ARM7微控制器处理传感器采集来的数据,并以CAN总线的方式与监控中心进行通信。     

基于CAN总线的电力系统参数采集和监控

介绍一种基于CAN总线的电力参数采集监控系统,系统由主控计算机、CAN总线适配卡和多个智能测控节点组成;各智能测控点则由80C196KC微控制器和电力参数采集专用芯片CS5460A构成现场测控电路。详细介绍了由新型独立CAN总线控制器SJA1000构成的CAN总线结口电路的组成和现场测控电路的硬件设计。实践表明:该系统能对5km配电范围的10个智能节点实行高精度的数据采集和有效监控。实现了配电系统参数的数字化采集和智能化管理,提高了配电系统运行的可靠性和效率。     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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