基于虚拟仪器技术的发动机功率与扭矩的测量

运用虚拟仪器Lab VIEW为开发平台,在参照GB/T 18297～2001汽车发动机性能试验方法的要求下,研制了发动机的功率和扭矩测试系统.该系统采用电涡流缓速器作为负载,运用PID控制方式,可以实现对发动的扭矩、功率等参数测量.具有实时数据动态显示、可视化强、测量准确、数据保存、自动绘图等优点.     

电流互感器精度在线评估系统

电流互感器的准确性是电力系统计量、保护和监测的重要保证.提出了一种新的基于带电作业技术的电流互感器精度评估方法,首先构建标准回路,采用带电作业把标准回路接入一次线路,然后比较标准回路和被测量回路的数据,系统就可以计算出被测量电流互感器的比差和角差.现场测试的结果表明了该方法的有效性和可行性,系统的测试精度达到0.1级.     

存储式变压器油压监测与保护系统的数据管理

针对机械式速动油压继电器的局限性,设计了存储式变压器油压监测与保护系统.该系统除了具有油压速动保护功能外,还能进行油压高/低报警,并能长期存储和管理油压数据.系统下位机以双C 8051F 340 CPU为核心,以U盘为介质,采用文本文件存储数据.上位机以ACCESS数据库为核心,完成数据存储、管理和分析.分析油压测量值、系统参数以及速动保护信号等各种数据的关系及其管理方法.该方法的实用性和有效性在实验室测试以及现场试用中得到了有效验证.     

轴类零件的磨损分析与检测系统设计

针对曲轴磨损情况提出了一种计算机辅助测试系统.该系统采用计算机控制,实现了测量数据的自动采集和处理,检测参数包括曲轴轴颈的径向圆跳动误差、直径和圆度等,经验证,测试结果满足使用要求.     

改进的RBFNN用于机器人三维表面 测量系统曲面重构

为克服三坐标测量机检测速度慢等缺点,提出机器人三维表面测量系统. 针对该系统设计了一种基于径向基神经网络(RBFNN)的简洁快速曲面重构方法. 该方法考虑到RBFNN选取的神经元函数为高斯函数,将机器人三维表面测量系统获得的点云数据投影到二维平面,然后将该二维平面平均分割,选取分割点为RBFNN神经元的中心,避免了模糊c-均值法选取中心需要迭代计算的缺点,并且重构的网络训练精度和测试精度均高于模糊c-均值法选取中心设计的网络精度. 利用该测量系统获得的实际点云数据验证了     

一种新型煤层瓦斯含量测量系统

针对现有煤层瓦斯含量测量方法中数据记录不及时、误差较大等缺点,提出一种新的瓦斯含量测量系统,利用最小二乘法拟合测量数据,得出样品的瓦斯解吸量与时间的函数关系,从而预测出瓦斯漏失量.根据现场测试需求,对瓦斯含量测量系统进行设计,采用微小流量气体传感器FS5001-200实现瓦斯解吸量精确测量,上位机采用VC实现数据拟合算法处理,最后得到煤样瓦斯含量.研究结果表明:该测量系统反应快速、实时性高、可操作性强、数据拟合精度高,可准确测量瓦斯含量.     

基于喷射角信息的淋浴花洒冲击力场测试方法研究

从理论和仿真两方面分析淋浴花洒喷射冲击力场的特性,在通过图像测量技术获得喷射角信息的前提下,提出单束冲击力的测试方法和多束射流冲击力场的测试结构,并给出测试系统的设计以及上位机数据的存储方法.实验表明,该方案能够实现多种规格淋浴花洒喷射冲击力场的测试和数据的实时存储.     

基于LabVIEW的电机测试系统的设计与研究

基于LabVIEW的电机测试平台是针对于传统方法已无法满足电机生产测试量的需求而提出来的,通过对方案和功能的设计能够完成电机出厂检测的基本测量任务,可以满足电机的动态性能测试,它具有便于操作、直观显示、工作简单等优点.探讨了测试系统的总体设计方案、技术原理以及对某型号异步交流电机的实际测试.实际测量数据表明本系统运行稳定,测量准确.     

电动多旋翼无人机转向能耗测试系统设计与试验

本文针对电动多旋翼无人机的能耗测试,设计了一种基于单片机的无人机转向能耗测试系统。该测试系统主要由角速度传感器,功率测量模块,无线通讯模块以及单片机等部分组成,并基于LabVIEW软件设计了上位机程序,以实现对测试过程数据的实时显示和保存。对系统进行试验表明：系统数据采集频率为100 Hz,电压测量精度为99.93 %,电流测量精度为99.87 %,转向角度测量精度为98.10 %,可见该系统测量精度较高,能满足电动多旋翼无人机转向能耗的测试及相关数据的获取。     

基于MSP430的线阵CCD数据采集系统

基于电荷耦合器件和单片机技术, 设计一个2 160像元的线阵图像采集系统. 该系统根据线阵电荷耦合器件驱动模块的要求, 设计了图像数据的高速采集与缓存、 串行通信接口上传与上位机显示软件. 该数据采集系统具有单次采集和连续采集两种工作模式, 图像刷新率可达5帧/s. 实验测试结果表明, 该线阵图像采集系统成本较低、 工作稳定、 使用方便, 可应用于产品尺寸测量和非接触尺寸测量.     

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

正~~