履带起重机力矩限制器传感器选型

在选择和使用履带起重机力矩限制器的传感器时要考虑安装方式、安全系数、信号类型、接线方式和成本等几个方面,下面分力传感器和角度传感器两方面介绍。     

起重机监控系统的设计

起重机力矩保护装置的设计在中国虽然已经有一段历史了,但传统的起重机力矩保护装置还有很多的问题与限制,本文设计的在线监控系统由数据采集模块和监控主机两个部分组成.整个系统采用中文显示,操作方便,实现了诸多工作参数的数字化集中显示与控制,提高了起重机的自动化程度和安全操作性.     

STM32F103在超载限制器中的应用

本文介绍了以STM32F103为核心芯片构成的超载限制器,用来控制起重机的安全运行。该系统具有保护、报警、实时记录并显示多个工作参数的功能,是一种可靠的起重机安全保护装置。     

单片机力矩限制器的研究

用MCS-96系列单片机中的8098作为主控芯片,用软件对起重力矩实现控制并自动报警和制动,成功地制成了单片机力矩限制器。经在新开发的百吨液压起重机上试用,表明具有良好的技术性能和经济效益。     

起重机械载荷试验中几个值得重视的问题

载荷试验是检验起重机械产品质量及安全性能的综合性的重要指标，通过载荷试验不仅可以检测出起重机金属结构的变形情况，如桥式起重机的挠度值等，还可以检测出起重机安全装置的有效情况，如超载限制器，塔式起重机在额定载荷状态下的力矩限制器的动作保护情况等。总之，载荷试验对检查起重机及其部件的结构承载能力，起重机的焊接、裂纹情况，永久性变形，联接松动情况，安全装置有效性及起重机性能与安全有影响的损坏情况，都是极为重要的。     

紧凑型内嵌扭矩传感器机器人关节设计

内嵌扭矩传感器的紧凑型一体化关节可增加机器人的负载质量比,提高力控安全性,更适用于服务行业。通过对轻型协作机器人关节的研究,提出了机器人关节系统整体设计方案。基于关节设计参数,研究关节系统工况负载下的可靠性。对关节扭矩特性进行分析,设计了17型号关节扭矩传感器本体,并采用有限元仿真方法,验证了应变片安装位置的合理性。研制了放大与低通滤波电路系统,并对传感器进行实验分析标定,拟合扭矩电压特性曲线,得到线性度、灵敏度、迟滞和零漂参数。最后对研制的关节整机进行负载测试,并应用于五自由度碳纤维轻型机械臂系统。结果表明:紧凑型内嵌扭矩传感器机器人关节质量轻、负载能力高,扭矩传感器具有较高的精度和灵敏度。     

海上采油平台电动吊车力矩仪改造

吊车是海上采油平台的重要设备之一,当吊机超载作业产生过大应力,可能使钢丝绳拉断、传动机构损坏、马达及液压缸憋压或者下滑,制动失效,甚至造成臂架折断、回转轴承解体,严重的可能导致整个起重机倾覆。在海上平台大多数起重机上安装力矩限制器和超载保护装置,针对平台电动吊车力矩仪因使用时间较长存在的重量数值漂移、显示背灯故障等问题进行分析,并对力矩仪进行了换型改造。     

在线带式输送机托辊工况动态监测系统的研发

开发了1种适用于各种型号带式输送机托辊的计算机监测系统。研究了托辊工况监测系统动态参数模型与计算方法,这种方法是基于理论力学中"转动惯量法"的原理,从力矩平衡的角度出发,建立起被测参数的数学模型。论述了监测系统的组成及工作原理,进行了系统硬件原理电路的设计和软件系统结构及数据处理应用程序的设计。分析了系统的测量精度和可靠性,由此得出该系统的设计能够满足使用要求。     

起重量限制器在电动单梁起重机上的设置及检验

本文主要讨论了起重量限制器的原理和特点及起重量限制器在电动单梁起重机上的安装形式,结合起重机检验中发现的问题,对起重量限制器的相关问题的解决进行探讨。     

基于AMEsim的起重机伸缩臂液压系统动态仿真

选取了QY-8型液压起重机的伸缩臂液压系统为研究对象,采用AMESim软件建立了液压回路仿真模型,通过模拟不同工况下的负载,对液压系统工作过程进行了动态仿真。分析不同的动态特性曲线发现,动态仿真结果与理论预期效果相符合,且仿真过程平稳,为更大载荷汽车起重机液压系统设计和参数优化提供了依据。     

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.     

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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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