数控铣、加工中心椭圆轮廓宏程序编程

零件中遇到公式曲线时,由于数控机床不能自动进行插补运动,这时可以采用计算机软件生成程序,但其生成的程序有弊端,不利于调整。本文介绍利用FANUC机床自带的宏程序编程方法,利用手工编程来解决公式曲线零编程问题。     

椭圆的近似画法在数控加工中的应用

通过对椭圆的四心近似画法的分析,介绍了椭圆的近似画法应用于数控编程与加工中,从而简化了程序的编写、提高了零件的加工效率的一种方法。     

椭圆问题自动求解系统—ELLPACK

ELLPACK是解椭圆问题的超高级系统,建立在软件部件技术的原理之上,其系统设计使得ELLPACK成为研究数值方法和解应用问题的极其灵活方便而有力的工具。ELLPACK作为面向问题的超高级语言展示了迈向科技计算现代化的重要步骤。本文首先描述了ELLPACK——椭圆问题自动求解系统的由来,演变和主要的先进特征,然后叙述了ELLPACK系统的结构、功能与原理,最后介绍了ELLPACK的近期及未来发展与演变,包括PC ELLPACK、交互式ELLPACK、分布式椭圆专家系统以及未来数学软件系统结构。     

椭圆切线面的展开

本文对两端处于平行平面上的椭圆的切线面进行了解析分析，提出了其展开方法，利用此方法可由计算机绘出展开图。     

用直径距离的拉线法描绘椭圆

本文介绍了一种鲜为人知的用直径距离描绘椭圆的方法。     

有效的椭圆曲线求阶算法

介绍了有限域Fq上椭圆曲线群的求阶算法:l-adic求阶方法、p-adic求阶方法.描述了各算法的理论依据,分析、比较了其优劣性及适用情况,为ECC安全参数的选取的设计者提供参考.     

数控车实训中斜椭圆的编程

一些外形复杂的曲面,如椭圆、双曲线、抛物线等,手动编程比较困难,而斜椭圆的编程较以上曲线更难,文中结合实例介绍了斜椭圆的加工。     

椭圆规（样品）研制报告

本文阐述了椭圆规的研制原理，将普通教具圆规改制成椭圆规的方法和其正确的使用方法。     

数控车床椭圆加工宏程序编制方法探究

随着数控加工技术的发展,宏程序在数控编程中被广泛地应用。本文阐述了数控车削加工中,椭圆宏程序的两种编制方法,并对其进行比较,解决了数控车削加工中椭圆曲线的插补问题。最后对宏程序编制进行了总结。     

椭圆曲线加密在智能卡中的应用

根据椭圆曲线加密算法的教学理论基础,对比分析了椭圆曲线加密算法的性能,得到了其安全曲线.并介绍了椭圆曲线加密算法在智能卡PIN鉴别中的算法和流程实现.     

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

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