Many papers present various analyses for comforming finite element multigrid methods which are often based on certain regularity and approximation assumptiom concerning smoother and the solution. In chapter three, we analyze the error convergence operator directly and analyze the V-cycle convergence for symmetry positive define elliptic boundary problem without regularity assumption.
协调有限元多重网格法近似解对称正定椭圆边值问题，往往要对解，光滑子作一定的正则性、逼近性假设，在无正则性弱假设条件的前提下，我们直接推导误差减少算子的收敛关系式，第三章主要分析了对称正定椭圆边值问题的多重网格V-循环收敛性。
Taking the error occurring in no-load test of three phase AC traction motor in our company as example, analyzing with symmetrical components method, the main cause of error-three phase non-symmetry and corresponding solutions were given in this paper.
在三相异步电动机的性能测试中，空载试验是最基本的试验项目之一。
Secondly, the key technology of how to align point cloud with surface feature model of human body, analyze error, adjust position are researched and the algorithms of calculating center of mass, inertia axis, and symmetry plane are successfully introduced.
其次，研究了如何将测量得到的人体点云数据与人体曲面特征模型对齐，进行误差分析，位置调整等关键技术，成功的将质心、惯性轴、对称面的计算方法引入到对齐过程中。
When the planing machines are used to machine long keyway, the machining errors will occur. The factors that can lead to machining errors, and make a comprehensive analysis on the main error, such as location error, symmetry error and tool error are described.
简述了普通刨床加工长键槽产生加工误差的多种因素，并对加工过程中产生的主要误差、定位误差、对称度误差和刀具误差进行了综合分析。
The fractional error estimation part analyzes the performance of SCA and conjugate symmetry algorithm. After comparing the performance of the two algorithms, we choose SCA, which has a larger estimation range and smaller error.
其中小数频偏估计部分详细分析了SCA算法和共轭对称算法的性能，再作出比较之后，选择了估计范围大，误差小的SCA算法；
Geometric optics is used to analyze the influence on beam transmission as circular symmetry manufacture error exists on an axicon.
用几何光学分析了圆锥透镜的锥面存在圆对称加工误差时，对光束传输变换的影响；
Influence of Manufacture Error with Non-Circular Symmetry in an Axicon on the Bessel Beams Quality
轴棱锥非圆对称加工误差对贝塞耳光束质量的影响
Systematic check of symmetry group tables (continued) & proof on the error of the general formula B of the space group p42/nnm
对称群表的系统校验（续）&论证P42/nnm总公式B的错误
Area detection, consistent constraint error detection, probability selection rule and symmetry optimization were successfully applied to the correction and completion of feature matching of curved scenes by epipolar constraints homography mapping in curved scenes.
使用对极约束和同形映射两种几何约束，通过采用面积检测、一致性约束误差检测、概率筛选规则和对称优化等策略，成功地实现了曲面场景图像的特征点匹配。
The taper control principle, compensation of gear clearance, compensation of top error, short circuit turn back were introduced and the data automatic produce method of symmetry and rotate cutting was analyzed.
重点介绍了锥度控制原理、齿隙补偿、端偏量补偿、短路回退，并分析了对称、旋转加工的数据自动生成方法。
Discussed a means to deal with dimensional chain computing with symmetry error in two way: computing analysis and geometry analysis.
从计算和几何分析两条途径，讨论尺寸链计算中对称度误差的处理方法，为类似计算提供参考意见。
A Means to Deal with Dimensional Chain Computing with Symmetry Error
尺寸链计算中对称度误差的处理方法
This paper discusses the cause of keyway symmetry error produced and test method and approaches to related calculating formulae.
论述了键槽对称度误差的产生原因以及检测方法，并对有关计算公式进行了探讨。
The radial and axial displacements of spherical arc center are primary reason for form error, and spherical symmetry error respectively.
球面圆弧中心径向位移是工件产生球面轮廓形状误差的主要原因，而球面圆弧中心轴向位移则是球面产生球形对称度误差的主要原因。
The error sources of IRO are analyzed. The spherical symmetry approximation of electron density is the main source of the inversion error.
分析电离层掩星误差源，指出电子密度分布的局部非球对称性是电离层掩星的主要误差源。
Diffraction theory and stationary phase method are adopted as a manufacture error is not a circular symmetry.
用衍射理论及稳相法分析了锥面的非圆对称加工误差及横截面由圆变为椭圆时，其后衍射光场的变化情况。
By analyzing the symmetry properties of the signal disturbance and introducting the ideal error dynamics equation, quarter-period repetitive controller for 2-order AR system is given in detail when the disturbance signal is sinusoidal, and extended to the N-order AR system.
通过分析扰动信号的对称特性，引入理想误差动态方程，给出了扰动信号为正弦时的二阶AR系统1/4周期重复控制器的具体设计方法，并将其推广至N阶AR系统。
Analyzed the reason of endpoint effect and proposed the method of combining Extreme Point Symmetry Continuation method and Gray Error Separation method to suppress the endpoint effect.
分析了端点效应产生的原因，提出了用极值点对称延拓法和灰色误差分离方法联合抑制端点效应的方法。
Besides, the mode of multiple sub-optimal fading factors in STF will destroy the symmetry and positive definiteness of the prediction error covariance matrix, which results in the filter divergence.
此外，多重渐消因子矩阵在原强跟踪滤波算法中的作用方式可能破坏误差协方差阵的对称正定性，导致滤波算法的发散。
However, the variance matrix of computation error gradually loses positive definite and symmetry in the recursion, which induce output divergence of system filtering.
但对于无轨迹卡尔曼滤波，由于在长时间的递推过程中使计算误差的方差矩阵逐渐失去正定性和对称性而导致系统滤波输出发散。