圆度测量中偏心的相关分离与修正

用相关技术原理，提出一种圆度测量中偏心误差的分离与修正方法．该方法仅用一个传感器测量出圆度的原始误差函数，并从中分离出试件在工作台上的安装偏心和圆度误差，避免了常规圆度测量中反复精密的调心，从而可以在不能调心的简易装置上测量圆度误差．     

圆度测量中偏心的相关分离与修正

用相关技术原理，提出一种圆度测量中偏心误差的分离与修正方法。该方法仅用一个传感器测量出圆度的原始误差函数，并从中分离出试件在工作台上的安装偏心和圆度误差，避免了常规圆度测量中反复精密的调心，从而可以在不能调心的简易装置上测量圆度误差。     

基于数字全息显微术的光纤连接器端面形貌检测技术

根据光纤连接器端面检测的要求,设计了运用数字全息显微术测量光纤连接器端面检测的光学系统和相应的再现方法.实验表明:该方法获得的结果清晰,可对光纤连接器端面的几何参数(如端面半径、球面顶点偏芯度和纤芯高度等)进行检测,同时可以重构端面的三维形貌.     

计算机辅助主轴回转误差测试与分析

讨论了计算机辅助主轴回转误差检测原理，分析了影响测量精度的因素，通过傅立叶变换分析，指出检测元件安装偏心和形状误差是影响主轴回转误差测量精度的主要因素．采用滤波技术消除检测元件安装偏心和形状误差的影响，达到精确获取主轴回转误差信息的目的．     

干涉仪测量球面曲率半径的精度分析

利用数字波面干涉仪对光学球面曲率半径进行直接测量和间接测量,分析了2种测量方法的误差来源及测量精度,给出了方法的适用范围和局限性.结果表明,基于光栅尺的直接测量方法的精度受限于齐焦位置与猫眼位置的判读精度,其测量不确定度在10~70μm的范围内,与f数相关并与球径仪的测量精度相当;利用平面干涉仪测量球面波矢高后间接计算曲率半径的方法适合f数大于1 000的长曲率半径的测量,其精度为0.8~0.3m,与干涉仪的标准平晶平面度和测试稳定性密切相关.通过提高标准平晶的平面度和控制测量环境,针对口径6mm、曲率半径9m的激光陀螺反射镜进行的曲率半径测量精度达到0.05m,与ZYGO NewView7 000 3D型表面轮廓仪的测试结果差异为0.03m.     

偏心度对方形倍频晶体温度场的影响

为了解决非均匀温升对非线性晶体倍频转换效率影响的问题，建立了方形非线性晶体模型．该模型在建立中考虑了基频光具有高斯分布，方形倍频晶体具有周边恒温、端面满足近似绝热等特点．根据非线性晶体腔内倍频的实际需要，给出了方形非线性晶体基频光辐射偏心度的定义，并利用热传导方程，得到了方形非线性晶体受基波偏心辐射时温度场分布的一般解析表达式，解决了在温场模式研究中将倍频使用的方形晶体近似为圆柱形晶体所带来的问题．实验结果表明；当基频光辐射偏心度增大到0．75时，倍频晶体的最高温升下降了21．1％．     

形状误差分离统一理论—解的确定性准则

形状误差分离的根本问题是误差分离方程的求解，其解是否存在，决定了形状误差能否分离．通过对现存的各种圆度、直线度、圆柱度及螺纹导程误差等形状误差分离技术的深入探讨，就形状误差分离技术的共同性质作了归纳，据此提出了在线误差测量和分离的一般方法，给出形式统一的矩阵方程．在此基础上，针对误差分离统一方程解的性质进行了详细讨论，应用矩阵理论给出了误差分离统一方程解的确定性准则．结合形状误差分离技术的具体实现，给出了多点法的测量传感器个数和多步法测量传感器移步步数的统一确定方法．     

圆度误差的范数评价

在评价测量对象的圆度误差时 ,必须将偏心分量从测量信号中分离出来 ,采用的方法有最小二乘法、卡尔曼滤波法和三传感器法等。这些方法不能分析非整次谐波 ,不能区分一次谐波和偏心分量 ,并且含有较大的非线性误差。本文提出一种用范数理论表征圆度误差的新方法 ,这种方法可以有效地衰减各种干扰误差 ,计算结果必然收敛于圆度误差的真值 ,而且参数估计误差很小。     

测量轴承摩擦力矩的实验装置及其精度

介绍一种能够精确测量轴承摩擦力矩的实验装置的结构，实验方法，数据处理公式及误差分析等，该装置测量精度高，重复性好，摩擦力矩和轴承载荷的测量误差〈０．３％，偏心矩测量精度０．１μｍ，偏位角误差也很小。     

物理实验中有关误差体系改革的几点看法

1概述误差和不确定度居于两个不同的概念和体系．[1]所谓误差，通常的定义是：（1）式中ε为误差或测量误差，工为给出值或测得值，A为真值．由于测量时随机误差的不可避免，真值是不能得到的；即误差的数值是求不出来的．误差体系中还有一个重要概念是偏差，它指的是多次测量时某次测量值与算术平均值之差：△xi=－x（2）被称作偏差的还有算术平均偏差和标准偏差．偏差、算术平均偏差和标准偏差，它们在测量中的值都是确定的，也是能够计算出其数值来的．航胃不确定度是指由于误差的存在而对被测量不能肯定的程度，它是一个描述尚未确定的…     

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.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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