查询词典 approximation error

It also can be used to measure the geometrical tolerance, such as straightness error, roundness error, cylindricity error, parallelism error, perpendicularity error, angularity error, coaxiality error, symmetry error and circular run-out error etc.

该仪器集机、光、电于一体，采用了新的光路系统和近些年最新的测量方法及数据处理方法，具有功能多、体积小、重量轻、操作方便、非接触测量、测量精度高等特点。

The second part has summarized from the one-dimension and multivariate respects the abundant approximation properties of Bernstein polynomials, mainly including the estimation of approximation degree, derivative approximation, linear combination approximation and weighted approximation.

第二部分从一元和多元两个方面系统总结了Bernstein算子丰富的逼近性质，主要包括逼近度估计、导数逼近、线性组合逼近和加权逼近等。

The close relationship between the Hybrid polynomial approximation and the classical Hermite polynomial approximation to rational curves and surfaces are studied, Hermite approximation is in fact a special case of Hybrid approximation. The sufficient and necessary condition for the convergence of Hybrid approximation to rational Bézier surface is deduced and proved.

围绕着有理曲线曲面的Hybrid逼近，作者研究了有理曲线曲面的Hybrid多项式逼近与传统的Hermite多项式逼近之间的密切关系，并指出Hermite逼近事实上是Hybrid逼近的一种特例，此后演绎并证明了有理Bézier曲面的Hybrid多项式逼近收敛的充分必要条件。

More than 30 kinds of meshfree methods are reviewed in this paper in the light of weighted residual method, and different meshfree methods can be viewed as different forms of weighted residual method and/or with different approximation functions. Various kinds of meshfree approximate schemes are presented in detail, including moving least square approximation, kernel and reproducing kernel approximation, partition of unity approximation, radial basis approximation, radial point interpolation and natural neighbor interpolation.

详尽介绍了各种无网格近似方案(包括移动最小二乘近似、核近似和重构核近似、单位分解近似、径向基函数近似、点插值近似、自然邻接点插值近似等)和无网格法中常用的各类加权余量法(伽辽金格式、配点格式、局部弱形式、加权最小二乘格式和边界积分格式等)，并讨论了数值积分方法和边界条件的处理等问题。

ABSTRACT This paper summarizes our researches on two key techniques in curve and surface modeling-the geometric approximation techniques and the geometric interpolation techniques. The former includes three types of geometric approximation techniques: Hybrid polynomial approximation to rational curves and surfaces, offset curves and surfaces approximation, interval Bézier curves and surfaces approximation. The latter includes a series of algorithms for shape blending modeling: the MSI algorithm for shape blending between space polylines or trees, the MSI algorithm for shape blending between triangular meshes, and skeleton-based shape blending algorithms using triangular decomposition and star-shape decomposition.

本文是作者对曲线曲面造型中两类核心技术几何逼近技术和几何插值技术的研究成果的总结，其中前者包括有理曲线曲面的Hybrid多项式逼近、等距曲线曲面逼近和区间曲线曲面逼近等三类几何逼近方法；后者包括用于形状混合造型的几何插值方法的一系列算法：空间多边形形状混合的MSI插值算法、三角网格形状混合的MSI插值算法、树的形状混合的MSI插值算法以及基于骨架树形状混合的三角剖分算法和星形剖分算法。

In this paper, some characteristic functions of the multifunctional single-flank mesh gear tester of model CD320G-D which is applying gear integrated error measuring technique, computer technique, error separation technique, fault diagnosis technique and error prediction technique, including automatic searching of profile error start point, determination of profile barrelling, separation of profile form error and profile slope error, measurement of profile error with evaluation range subtracting tooth tip, measurement of tooth topograph and statistical analysis of gear manufacture error, are presented.

阐述了综合应用齿轮整体误差测量技术、计算机技术、误差分离技术、故障诊断技术和误差预报技术的多功能 CD320G-D 型单啮仪的一些具有特色的功能。这些功能包括齿形误差起测点的自动找定、凸形齿凸形量的测定及其形状误差与倾斜误差的分离、取值范围扣除齿顶部的齿形误差的测量、齿面轮廓度误差的测量以及齿轮加工误差的大样本统计分析。

In generic mathematical approximation methods Chebyshev multinomial approximation algorithm has better effect on reducing approximation error. This paper brought forward a parallel Chebyshev multinomial approximation algorithm based on a unique representation of complex curve, and implemented the parallel program in two Java methods.

常用的数学逼近法中切比雪夫多项式拟和法误差较小，对此，提出一种基於复杂曲线表示的切比雪夫多项式拟合并行算法，并采用两种Java方案实现并行程序。

Second, the data checking and correction process, to understand the various sources of measurement error, its three main areas: equipment error (determined by the instrument itself, is an objective source of error), observation error (due to the technical level personnel a result of belonging to a subjective source of error), external influence error (subject, such as temperature, atmospheric refraction effects of external factors such as these factors are also constantly changing and difficult to control, belonging to a variable source of error).

其次，在对数据的检查和矫正的过程中，明白了各种测量误差的来源，其主要有三个方面：仪器误差（仪器本身所决定，属客观误差来源）、观测误差（由于人员的技术水平而造成，属于主观误差来源）、外界影响误差（受到如温度、大气折射等外界因素的影响而这些因素又时时处于变动中而难以控制，属于可变动误差来源）。

To analyze the pseudo phenomena caused by migration velocity error, the paper firstly studied the depth error between post-stack migration and prestack migration caused by same velocity error, and found the depth error was only relative to velocity error and had no direct matter with methods of depth migration (post-stack migration or prestack migration). Then the paper did numerical simulation of a complex lenticular body model with wave-equation modeling and migration, and found that the velocity error could not only induce depth error, but also could change the modality of construction and the event of subjacent layers. Furthermore, it could change the frequency of reflective event. They are the pseudo phenomena caused by migration.

从分析偏移速度误差带来的各种假象出发，本文首先对比分析了速度误差对叠后深度偏移和叠前深度偏移的影响，发现偏移剖面的深度误差仅与速度模型的误差有关系，与具体的偏移方法没有直接的关系；然后对一个复杂的透镜体模型进行了波动方程叠后正演和偏移计算，详细地讨论了不同的速度误差带来的各种假象，发现速度误差不仅会带来深度误差，而且会造成构造体的形态变化，下覆地层同向轴的扭曲，还可能引起地层同向轴的频率发生变化，给资料解释带来一定的假象。

Error analysis In order to analysis the pose error of the hexapod machine tool, considering the characteristics of the parallel mechanism,"analysis on the error prominency factors for the hexapod machine tool pose error"is proposed. Numerically, the error prominency factor can express the influence on the pose error of the tool resulted from the mechanism parameter error within the whole workspace.

四、位姿误差分析为了定量地对并联机器人机床位姿误差进行分析，结合并联机构的特点，首次提出了&并联机器人机床位姿误差放大因子分析法&，因位姿误差放大因子是反映机床机构参数误差对刀具末端误差影响大小的机床工作空间内的统计值，因此既可作为机床结构参数精度设计的依据又可对机构参数进行优化。

Fostering the concept of multi-culture firmly and mastering the development of advanced culture correctly are conductive to resisting terrorism, separatism of nationalities and ultraism of religion, which is of great academic theoretical, immediate and profound historical si...

牢固树立多元文化的理念和正确把握先进文化的发展方向，有助于在世界范围内自觉地抵制恐怖主义，民族分裂主义和宗教极端主义。不仅具有重大的学术理论意义，而且也具有重大的现实意义和深远的历史意义。

But if anyone walks in the night, he stumbles, because the light is not in him.

11：10 若在黑夜行走，就必碰跌，因为那光不在他里面。