机器人复合加工模具曲面工艺参数的研究

本文提出了一种由机器人和超垢电火花复合抛光机组成的自动研磨加工系统，试验表明，本研究为进一步拓展模具曲面的加工技术领域提供了一种新的方法     

高精度模具的超精密加工

通过分析仿形加工、NC加工的特点，提出一种将其两有机结合的加工系统．对模具型腔表面研磨及抛光的方法进行了分析比较，提出在加工中将各种方法加以组合，以提高加工效率．     

反求工程在复杂曲面模具制造中的应用

介绍了以反求工程为技术支撑的复杂曲面模具数控加工的基本原理和实现过程关键技术-样件表面数字化技术和曲面重构技术.综述了基于反求工程技术的复杂曲面模具制造过程中的应用现状及特点,并以其在鼠标模具制造中的应用,说明反求工程技术在复杂曲面模具的快速设计和加工制造中可缩短产品的研发周期,增强市场竞争力.     

汽车覆盖件模具CAPP关键技术研究

在分析汽车覆盖件模具CAD/CAM技术特点和覆盖件模具CAPP关键技术基础上,提出了基于宏工艺的面向数控编程的包含自由曲面类零件数控加工工艺规划模型,解决了曲面加工特征识别的难题。并提出了曲面数控加工区域划分的概念,在子区域内优化走刀路线的策略,解决了曲面数控加工刀具轨迹优化问题。     

基于Windows98磁粒光整加工CNC系统的开发研究

磁粒研磨是复杂模具高精度光整加工最具潜力的方法之一.为解决模具型腔表面高精度光整加工的难题,将磁粒光整加工与数控技术结合起来,以开放式CNC体系为指导思想,在Windows98下开发适合磁粒光整加工的三坐标CNC系统.采用了VXD技术进行Windows98下的实时中断操作.用所开发的CNC系统进行试验研究,结果表明磁粒光整加工能大大降低模具表面粗糙度.该结论对模具高精度光整加工自动化的研究具有重要意义.     

汽车覆盖件模具CAPP关键技术研究

在分析汽车覆盖件模具CAD/CAM技术特点和覆盖件模具CAPP 关键技术基础上,提出了基于宏工艺的面向数控编程的包含自由曲面类零件数控加工工艺规划模型,解决了曲面加工特征识别的难题-并提出了曲面数控加工区域划分的概念,在子区域内优化走刀路线的策略,解决了曲面数控加工刀具轨迹优化问题.     

模具高速加工技术与策略

在现代模具的成形制造中,由于模具的形面设计日趋复杂,自由曲面所占比例不断增加,因此对模具加工技术提出了更高要求,即不仅应保证高的制造精度和表面质量,而且要追求加工表面的美观。随着对高速加工技术的研究不断深入,尤其在加工机床、数控系统、刀具系统、CAD/CAM软件等相关技术不断发展的推动下,高速加工技术已越来越多地应用于模具的制造加工。     

一种自主研磨机器人搜索未知自由曲面模型技术研究

为解决正交双目立体视觉自主研磨机器人对未知自由曲面的加工问题,结合全区域搜索技术、待加工轮廓的选择算法和曲面边界识别方法,提出一种适用于未知曲面加工的自主搜索方法,实现了研磨机器人对非结构化环境中未知曲面的目标搜索任务.研磨机器人利用线激光和视觉传感器来感知未知待加工曲面,采用光轴正交的两个相机同时采集研磨曲面轮廓的图像,并利用模糊逻辑方法进行局部路径规划,在此基础上通过全区域搜索技术实现对未知待加工区域的遍历.同时采用图像处理技术,即动态边界识别方法辨识目标并确定其位置.该未知待加工曲面自主搜索方法可以从曲面任意位置开始加工,算法对于非结构化自由曲面具有良好的适应性.实验结果验证了算法的可行性.     

多轴联动空间复杂曲面线切割加工技术

为实现大锥度空间复杂曲面模具零件的线切割加工,解决高速走丝电火花线切割机床加工空间曲面的难题,以空间曲面零件电火花线切割加工运动规律数学模型为基础,设计开发一种带有自动分度功能的、可翻转的数控回转工作台;基于原有的高速走丝数控电火花线切割机床,研制空间复杂曲面多轴联动高速走丝线切割加工系统,并进行螺旋面、锥面、锥台、双曲面和正弦曲面等典型空间曲面零件的电火花线切割加工实验,对加工出的各个实验样件进行了测量和加工误差分析.研究结果表明:所设计的空间复杂曲面多轴联动线切割加工系统具有较高的加工效率、较好的加工质量和较低的成本;加工样件的误差在允许范围内,验证了该系统的实用性,为解决高速走丝电火花线切割加工空间曲面的难题提供了一种思路.     

SUS304不锈钢平面磁力研磨加工试验研究

采用自行设计的磁力研磨装置,对SUS304不锈钢板进行研磨试验,分析了加工时间对磁力研磨效果的影响.试验结果表明:加工初期,不锈钢表面粗糙度值下降较快,加工效率高;超过一定时间后,研磨效率降低.在磁力研磨过程中,存在一个使得研磨加工效率最高的最佳加工时间.     

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