基于LabviEW的动平衡测试系统设计

动平衡机是教学实验、工程测试中的重要设备。该文针对老式平衡机操作繁琐、测试精度低、工作效率低的缺点，引入数据采集系统（DAQ）和LabviEW软件平台，采用新的动平衡计算方法来改造原有的测试系统，实现了不平衡量的量化测量，有效地提高精度和工作效率。     

一种质量质心测量系统设计

稳定平台的静不平衡对系统在大过载状态下的工作性能影响很大,而精确测量稳定平台的质量质心能够将系统静不平衡量调整到最小。文章针对一般稳定平台系统的结构特点,设计了一种采用力矩平衡原理的质量质心测试系统,可以满足稳定平台精确调整静平衡的要求。     

力平衡式传感器在力测试系统实验的应用

将力平衡式传感器应用于力测试系统实验，可使测量精度、灵敏度和稳定性等指标大大提高。章阐述了将涡流传感器、激振器以及力平衡式传感器用于力测试系统的测量原理和实验过程。     

转子自动平衡理论及应用研究

对转子自动平衡问题进行了理论和应用研究。针对自动平衡的特点，对振动系统的力学模型进行了新的分析，指出：运用补偿方法，可以得到精确的系统模型，克服了传统通用平衡机中存在的原理误差提出了一种软件、硬支承自动平衡机的通用测试理论，详细介绍了研制的自动平衡系统的主要功能和技术关键。     

浅谈企业水量平衡测试中发现的几个问题及建议

水量平衡测试是指对用水单元和用水系统的水量进行系统的测试、统计、分析得出水量平衡关系的过程。简述了企业水量平衡测试中出现的问题,提出解决的建议,以增强人员的节水意识、提高企业用水水平。     

现场转子动平衡测试方法

将被动平衡的回转机械视为一个线性系统，根据线性系统满足叠加原理的特点，采用试配重的方法，利用一般测试仪器，测试出原始不平衡引起的振动幅值与基准相角和试加配重后引起的振动幅值确定不平衡质量大小，进而减轻设备的振动。     

两轮自平衡机器人动力学模型分析及PID 控制方法研究

针对两轮自平衡机器人高阶次、不稳定、多变量、非线性、强耦合的特点，以其为研究对象，采用Lagrange方法建立状态方程，并对其平衡控制进行了研究，采用STM32单片机设计了控制系统进行验证，以寻求最优的系统动态性能，提高系统稳定性和鲁棒性。根据机器人俯仰角度和速度等输入参数，采用 PID算法输出 PWM 占空比可变的脉冲对驱动电机进行控制。仿真实验证明，本方法具有较好的动态性能和快速性。通过实际测试，证明了本方法的有效性。
     

基于虚拟仪器的电能质量监测和分析的软件设计

电能质量监测和分析系统是结合计算机技术与现代测试技术构成的虚拟仪器系统。主要阐述了频率、电网谐波、三项不平衡度等部分电能质量指标的分析算法；介绍了采用虚拟仪器软件开发工具LabVIEW(1aboratory virtual instnament engineering workbench)监测和分析电能质量的方法，并给出了部分程序。     

惯性平台不平衡力矩测试方法及补偿控制

为了消除惯性平台在导弹飞行过程中受到的不平衡力矩对其稳定性和跟踪精度的影响,提出了惯性平台不平衡力矩的测试和补偿方法.在得出平台内外框架静平衡条件的基础上,采用多个称重传感器对内外框架进行测试,得到每个框架不平衡力矩值,从而推导出在弹体运动的动态环境下内外框不平衡力矩的算式.根据不平衡力矩测试结果和算式,建立了基于不平衡力矩补偿的惯性平台内框控制模型.通过MATLAB/Adams对该模型进行联合仿真,结果表明了该补偿方法的有效性.     

滑动轴承不平衡弹性转子系统周期运动的稳定性

利用快速Galerkin方法，结合Floquet理论，在较大的参数范围内研究了滑动轴承不平衡弹性转子系统周期运动的稳定性并进行了数值模拟。研究发现，考虑转子弹性后，较小的不平衡量使得转子刚性较大的系统Hopf分岔提前，而使得转子刚性较小的系统Hopf分岔滞后。系统刚性不同使得倍周期分岔形状发生了很大的变化，从而使得系统在参数空间的失稳途径不同。在较小的不平衡量范围内，随着转速的增大，转子刚性较大的系统失稳方式有两种，而转子刚性较小的系统失稳方式只有其中一种。在较大的不平衡量的范围内，无论转子刚性大小，系统失稳方式相同。     

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