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A Study Regarding Solution of a Knowledge Model Based on the Containing-Type Error Matrix Equation 被引量:1
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作者 Xilin Min Kaizhong Guo Jize Huang 《Engineering(科研)》 2012年第8期484-492,共9页
An error matrix equation based on error matrix theory was presented in previous research of the error-eliminating theory. The purpose of solving the error matrix equation is to create a decision support on how to swit... An error matrix equation based on error matrix theory was presented in previous research of the error-eliminating theory. The purpose of solving the error matrix equation is to create a decision support on how to switch from bad to good status. A matrix based on error logic is used to express current status u, expectant status u1 and transformation matrix T. It is u, u1, and T that are used to build error matrix equation T (u)= u1. This allows us to find a method whereby bad status “u” changes to good status “u1” by solving the equation. The conversion method that transform from current to expectant status can be obtained from the transformation matrix T. On this basis, this paper proposes a new kind of error matrix equation named “containing-type error matrix equation”. This equation is more suitable for analyzing the realistic question. The method of solving, existence and form of solution for this type of equation have been presented in this paper. This research provides a potential useful new technique for decision analysis. 展开更多
关键词 error matrix SET EQUATION Containing-Type error matrix EQUATION KNOWLEDGE Model
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MATRIX ALGORITHMS AND ERROR FORMULA FOR BIVARIATE THIELE-TYPE RECTANGULAR MATRIX VALUED RATIONAL INTERPOLATION 被引量:1
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作者 顾传青 朱功勤 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1999年第2期195-208,共14页
A new method for the construction of bivariate matrix valued rational interpolants (BGIRI) on a rectangular grid is presented in [6]. The rational interpolants are of Thiele-type continued fraction form with scalar de... A new method for the construction of bivariate matrix valued rational interpolants (BGIRI) on a rectangular grid is presented in [6]. The rational interpolants are of Thiele-type continued fraction form with scalar denominator. The generalized inverse introduced by [3]is gen-eralized to rectangular matrix case in this paper. An exact error formula for interpolation is ob-tained, which is an extension in matrix form of bivariate scalar and vector valued rational interpola-tion discussed by Siemaszko[l2] and by Gu Chuangqing [7] respectively. By defining row and col-umn-transformation in the sense of the partial inverted differences for matrices, two type matrix algorithms are established to construct corresponding two different BGIRI, which hold for the vec-tor case and the scalar case. 展开更多
关键词 BIVARIATE matrix VALUED RATIONAL inter polants error FORMULA matrix algorithms.
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Separation of Comprehensive Geometrical Errors of a 3-DOF Parallel Manipulator Based on Jacobian Matrix and Its Sensitivity Analysis with Monte-Carlo Method 被引量:16
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作者 SUN Tao SONG Yimin +1 位作者 LI Yonggang2 XU Liang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第3期406-413,共8页
Parallel kinematic machines (PKMs) have the advantages of a compact structure,high stiffness,a low moving inertia,and a high load/weight ratio.PKMs have been intensively studied since the 1980s,and are still attract... Parallel kinematic machines (PKMs) have the advantages of a compact structure,high stiffness,a low moving inertia,and a high load/weight ratio.PKMs have been intensively studied since the 1980s,and are still attracting much attention.Compared with extensive researches focus on their type/dimensional synthesis,kinematic/dynamic analyses,the error modeling and separation issues in PKMs are not studied adequately,which is one of the most important obstacles in its commercial applications widely.Taking a 3-PRS parallel manipulator as an example,this paper presents a separation method of source errors for 3-DOF parallel manipulator into the compensable and non-compensable errors effectively.The kinematic analysis of 3-PRS parallel manipulator leads to its six-dimension Jacobian matrix,which can be mapped into the Jacobian matrix of actuations and constraints,and then the compensable and non-compensable errors can be separated accordingly.The compensable errors can be compensated by the kinematic calibration,while the non-compensable errors may be adjusted by the manufacturing and assembling process.Followed by the influence of the latter,i.e.,the non-compensable errors,on the pose error of the moving platform through the sensitivity analysis with the aid of the Monte-Carlo method,meanwhile,the configurations of the manipulator are sought as the pose errors of the moving platform approaching their maximum.The compensable and non-compensable errors in limited-DOF parallel manipulators can be separated effectively by means of the Jacobian matrix of actuations and constraints,providing designers with an informative guideline to taking proper measures for enhancing the pose accuracy via component tolerancing and/or kinematic calibration,which can lay the foundation for the error distinguishment and compensation. 展开更多
关键词 parallel kinematic machines (PKMs) limited-degree-of-freedom (limited-DOF) error separation accuracy analysis Jacobian matrix compensable error non-compensable error sensitivity analysis
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基于新一代几何技术规范的装配误差建模
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作者 杨朝晖 高天石 +1 位作者 李崇赫 贺子力 《计算机集成制造系统》 EI CSCD 北大核心 2024年第1期118-128,共11页
针对由于公差设计不合理而导致的服役于复杂工况的机械装备性能下降等问题,提出一种综合考虑制造与装配误差的机械产品装配精度分析方法。该方法首先利用有限元分析机械装备零部件装配误差导致的变形,并提取发生形变的关键特征面;然后... 针对由于公差设计不合理而导致的服役于复杂工况的机械装备性能下降等问题,提出一种综合考虑制造与装配误差的机械产品装配精度分析方法。该方法首先利用有限元分析机械装备零部件装配误差导致的变形,并提取发生形变的关键特征面;然后基于新一代几何技术规范(GPS)将特征面的变形转化为尺寸与形位公差数据,并与设计公差进行叠加,实现变形—误差—公差的转换;随后基于雅可比旋量理论,构建综合考虑制造与装配误差的公差分析模型支撑机械装备的公差精量化设计;最后以某型机载作动筒为工程应用对象,对比分析了是否考虑受力变形条件下装配精度分析的结果差异,结果显示该方法相较于原有方法具有更高的计算准确性,能为精密机械产品精度设计提供更加准确的指导。 展开更多
关键词 雅可比旋量 变形 公差建模 修正矩阵 装配精度分析
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B-Dashnic-Zusmanovich矩阵线性互补问题误差界的估计
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作者 李艳艳 《文山学院学报》 2024年第2期53-55,共3页
研究B-Dashnic-Zusmanovich矩阵线性互补问题的误差界,利用Dashnic-Zusmanovich矩阵M的线性互补误差界估计式,得到了B-Dashnic-Zusmanovich矩阵误差界的估计式。
关键词 B-Dashnic-Zusmanovich矩阵 线性互补 误差界
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同步相移横向剪切干涉中偏振器件的误差建模
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作者 张郁文 刘丙才 +3 位作者 王红军 田爱玲 任柯鑫 王凯 《中国光学(中英文)》 EI CAS CSCD 北大核心 2024年第3期640-647,共8页
为了对同步相移横向剪切干涉系统中偏振器件的选型、装调以及误差补偿提供可靠的理论依据,本文根据琼斯矩阵原理,构建了系统中1/4波片和偏振片阵列误差对测量结果影响程度的误差模型,对四分之一波片的相位延迟误差、快轴方位角误差以及... 为了对同步相移横向剪切干涉系统中偏振器件的选型、装调以及误差补偿提供可靠的理论依据,本文根据琼斯矩阵原理,构建了系统中1/4波片和偏振片阵列误差对测量结果影响程度的误差模型,对四分之一波片的相位延迟误差、快轴方位角误差以及偏振片阵列透光轴方位角误差对测量结果的影响进行了定量分析。仿真结果表明:1/4波片的相位延迟误差在±1°以内时,波面测量误差为0.00002λ(PV)和0.000062λ(RMS);1/4波片的调整精度在±2°以内时,波面测量误差为0.0001λ(PV)和0.00006λ(RMS);偏振片阵列方位角误差在±1°以内时,测量误差为0.003λ(PV)和0.001λ(RMS)。根据仿真结果对测量系统中偏振元器件进行选型,同时选择两种不同精度的偏振元器件进行对比实验。实验结果的残差值与仿真结果的残差值的PV以及RMS值偏差均小于λ/20,可以在一定程度上验证模型的有效性。本文提出的数学模型可以为同步相移横向剪切干涉系统中偏振器件的选型提供可靠的理论依据。 展开更多
关键词 横向剪切干涉 同步相移 偏振器件 误差建模 琼斯矩阵
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Dashnic-Zusmanovich矩阵的扩展垂直线性互补问题的误差界研究
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作者 蒋建新 《文山学院学报》 2024年第2期56-58,67,共4页
利用Dashnic-Zusmanovich矩阵的结构特点和不等式的放缩技巧,得到了矩阵A的逆矩阵的无穷范数|A^(-1)|_(∞)的上界估计式,在该估计式的基础上,得到了该类矩阵的扩展垂直线性互补问题的误差界。
关键词 Dashnic-Zusmanovich矩阵 无穷范数 扩展垂直线性互补 误差界
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样本选取对地质灾害易发性评价的影响——以山西柳林县为例
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作者 陈建平 辛亚波 +4 位作者 王泽鹏 陈伟 万长园 刘云艳 黄俊杰 《中国地质灾害与防治学报》 CSCD 2024年第3期152-162,共11页
非地质灾害样本的合理选取对地质灾害易发性预测准确度的提高具有重要意义。文章以柳林县为例,选取适宜的影响因子,基于GIS技术采用随机森林模型进行易发性评价。以地质灾害与非地质灾害比例为1∶1、1∶1.5、1∶3、1∶5、1∶10和非地质... 非地质灾害样本的合理选取对地质灾害易发性预测准确度的提高具有重要意义。文章以柳林县为例,选取适宜的影响因子,基于GIS技术采用随机森林模型进行易发性评价。以地质灾害与非地质灾害比例为1∶1、1∶1.5、1∶3、1∶5、1∶10和非地质灾害点距已知灾害点100,500,800,1000 m为选取条件交叉结合共创建20组模型进行分析。结果表明:(1)通过误差指标、混淆矩阵和ROC曲线检验,样本比例和距已知灾害点距离变化对地质灾害易发性评价结果有较大影响。随着样本比例变小,距已知灾害点距离增加,各模型平均绝对误差和均方根误差整体下降,准确率整体上升。各模型ROC曲线下面积值均大于0.8,均有较好的预测效果。当样本比例小于1∶3时,距已知灾害点距离增加对模型误差和准确率影响较小,变化趋于稳定。综合判断样本比例为1∶10、距已知灾害点1000 m为最适合研究区模型。(2)高和极高易发区主要分布在中部及北部道路和河流两侧的地区,是柳林县防灾减灾的重点区。(3)样本选取差异导致易发性结果不同主要是因为建模过程中随机森林模型对数据特征的采集及判断发生变化,样本是否具有代表性发生变化。这些研究成果对当防灾减灾工作的实施具有重要意义。 展开更多
关键词 非地质灾害 GIS 随机森林 易发性 误差 混淆矩阵 ROC
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基于JADE-斜投影的鲁棒波束形成算法
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作者 程永杰 李纯 +1 位作者 刘帅 金铭 《系统工程与电子技术》 EI CSCD 北大核心 2024年第2期401-406,共6页
针对矩阵重构类波束形成算法对阵列幅相误差敏感的问题,提出一种基于盲源信号分离和斜投影的矩阵重构鲁棒波束形成算法。首先,依靠盲源分离技术得到接收信号和混合矩阵,结合期望信号先验信息完成混合矩阵中信号导向矢量的搜索。然后,利... 针对矩阵重构类波束形成算法对阵列幅相误差敏感的问题,提出一种基于盲源信号分离和斜投影的矩阵重构鲁棒波束形成算法。首先,依靠盲源分离技术得到接收信号和混合矩阵,结合期望信号先验信息完成混合矩阵中信号导向矢量的搜索。然后,利用盲源分离得到的信号协方差矩阵完成阵列幅相误差估计。最后,基于幅相误差校准的混合矩阵和斜投影思想,构建各干扰的斜投影算子,将接收数据分别向干扰斜投影空间进行投影,得到对应的干扰信号,完成干扰噪声协方差矩阵重构。仿真结果表明,所提方法对阵列幅相误差具有较好的鲁棒性,验证了算法的有效性。 展开更多
关键词 鲁棒波束形成 矩阵重构 幅相误差 盲源信号分离 斜投影
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基于Reed-Solomon码的Data Matrix条码纠错研究 被引量:1
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作者 赖忠喜 占红武 《机电工程》 CAS 2009年第8期62-65,共4页
为了研究Data Matrix条码的纠错能力,首先介绍了Data Matrix条码的特点和Reed-Solomon码的基本概念;接着研究了Reed-Solomon码在Data Matrix二维条码中的应用,重点分析了Data Matrix二维条码中Reed-Solomon编、解码的基本原理与步骤,并... 为了研究Data Matrix条码的纠错能力,首先介绍了Data Matrix条码的特点和Reed-Solomon码的基本概念;接着研究了Reed-Solomon码在Data Matrix二维条码中的应用,重点分析了Data Matrix二维条码中Reed-Solomon编、解码的基本原理与步骤,并用C语言实现它的编、解码算法;最后对Reed-Solomon码的纠错能力进行了测试。实验结果表明,Data Matrix二维条码采用Reed-Solomon码作为纠错码,可以有效地排除干扰并进行纠错。 展开更多
关键词 数据矩阵 Reed—Solomon码 纠错码 Euclid算法
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基于Reed-Solomon算法的DataMatrix条码纠错码的研究 被引量:5
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作者 陈刚 王典洪 《现代电子技术》 2006年第5期57-58,61,共3页
DataMatrix是一种矩阵二维条码,具有信息密度大、容量高、面积小等优点,同时,其译码时受噪声干扰也较大,因此,DataMatrix二维条码采用了ReedSolomon算法作为纠错码,可以有效地排除干扰进行纠错。首先介绍DataMatrix条码的特点,然后详细... DataMatrix是一种矩阵二维条码,具有信息密度大、容量高、面积小等优点,同时,其译码时受噪声干扰也较大,因此,DataMatrix二维条码采用了ReedSolomon算法作为纠错码,可以有效地排除干扰进行纠错。首先介绍DataMatrix条码的特点,然后详细介绍了ReedSolomon算法的原理和伽罗华域的基本运算规则和构造规则,重点分析研究他在DataMatrix二维条码中的应用,构造了他的实现算法和其纠错编码的实现电路并通过实例进行了具体的说明,同时讨论了RS的译码步骤。 展开更多
关键词 DATA matrix 伽罗毕域 Reed-Solomon算法 纠错码
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基于评分矩阵与评论文本融合的混合推荐模型
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作者 周梁 《蚌埠学院学报》 2024年第2期107-113,共7页
推荐系统已在电子商务中迅速推广应用,其带来的数据稀疏性增加了评分预测的不准确因素。提出了一种将评分和评论文本相融合的混合推荐模型(MRB),将用户偏好影响因子引入用户评分预测模型(UBP)中,将项目-时间因子引入项目评分预测模型(I... 推荐系统已在电子商务中迅速推广应用,其带来的数据稀疏性增加了评分预测的不准确因素。提出了一种将评分和评论文本相融合的混合推荐模型(MRB),将用户偏好影响因子引入用户评分预测模型(UBP)中,将项目-时间因子引入项目评分预测模型(IBP)中,通过推荐结果平均绝对误差(MAE)实验验证,当近邻数为50时,该模型明显优于传统的模型。 展开更多
关键词 评分矩阵 矩阵分解 评论文本 平均绝对误差
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Linear Error Equation on Field F_2 被引量:3
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作者 XIA Jian-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第4期518-522,共5页
在这份报纸,我们将给一个方法在 F2 上解决线性错误 equationon,由使用地 F2 和分区理论上的线性代数学。
关键词 误差方程 排列矩阵 加权平均 线性代数
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收发未精确同步条件下非相关多运动辐射源TOAs/FOAs协同定位方法
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作者 王鼎 尹洁昕 +1 位作者 郑娜娥 杨宾 《电子学报》 EI CAS CSCD 北大核心 2024年第2期550-563,共14页
在联合到达时间/到达频率的无线定位体制中,除了TOAs/FOAs(Time-Of-Arrivals/Frequency-Of-Arrivals)估计误差与传感器位置/速度先验观测误差以外,收发两端的传感器时钟同步误差也是影响定位精度的重要因素.为了抑制时钟同步误差和各类... 在联合到达时间/到达频率的无线定位体制中,除了TOAs/FOAs(Time-Of-Arrivals/Frequency-Of-Arrivals)估计误差与传感器位置/速度先验观测误差以外,收发两端的传感器时钟同步误差也是影响定位精度的重要因素.为了抑制时钟同步误差和各类观测误差的影响,本文针对非相关多运动辐射源定位场景,提出一种基于加权多维标度分析的TOAs/FOAs多辐射源协同定位方法.文中首先通过构造两组标量积矩阵推导定位关系式,然后基于一阶误差分析方法得到该关系式中的误差渐近统计特性,并进而构建联合定位与时钟同步误差校正的优化准则.针对此优化模型,本文提出一种基于正交投影矩阵数学性质的参数解耦合优化算法,可实现对多运动辐射源位置/速度参数与同步误差参数的分步估计,显著降低了参与优化迭代的变量维数.此外,文中还在收发未精确同步条件下推导TOAs/FOAs多辐射源协同定位模型的克拉美罗界,定量证明多辐射源协同定位可以带来性能增益,并且利用一阶误差分析以及正交投影矩阵数学性质证明新方法的渐近统计最优性.仿真实验结果验证所提出的协同定位方法的优越性. 展开更多
关键词 协同定位 到达时间 到达频率 时钟同步误差 加权多维标度分析 正交投影矩阵 理论性能分析 克拉美罗界
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SYSTEMATIC ERROR FROM Th/U RATIO IN LUMINESCENCE AND ESR DATING
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作者 Li Shenghua and Man-Yin Wong Tso(Radioisotope Unit,University of Hong Kong,Hong Kong) 《Nuclear Science and Techniques》 SCIE CAS CSCD 1995年第2期113-116,共4页
SYSTEMATICERRORFROMTh/URATIOINLUMINESCENCEANDESRDATINGLiShenghuaandMan-YinWongTso(RadioisotopeUnit,Universit... SYSTEMATICERRORFROMTh/URATIOINLUMINESCENCEANDESRDATINGLiShenghuaandMan-YinWongTso(RadioisotopeUnit,UniversityofHongKong,HongK... 展开更多
关键词 考古学 荧光 ESR 年代断定 综合误差
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On the Matrix and Additive Communication Channels
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作者 Vladimir Leontiev Garib Movsisyan +1 位作者 Arthur Osipyan Zhirayr Margaryan 《Journal of Information Security》 2014年第4期178-191,共14页
The notion of a communication channel is one of the key notions in information theory but like the notion “information” it has not any general mathematical definition. The existing examples of the communication chan... The notion of a communication channel is one of the key notions in information theory but like the notion “information” it has not any general mathematical definition. The existing examples of the communication channels: the Gaussian ones;the binary symmetric ones;the ones with symbol drop-out and drop-in;the ones with error packets etc., characterize the distortions which take place in information conducted through the corresponding channel. 展开更多
关键词 ADDITIVE Communication CHANNEL error matrix CHANNEL NEIGHBORHOOD CORRECTING Code ALPHABET
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Applications of Graph Theory to Gross Error Detection for GPS Geodetic Control Networks 被引量:1
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作者 Samwel Simon Katambi 《Geo-Spatial Information Science》 2002年第4期26-31,共6页
This paper describes a broad perspective of the application of graph theory to establishment of GPS control networks whereby the GPS network is considered as a connected and directed graph with three components.In thi... This paper describes a broad perspective of the application of graph theory to establishment of GPS control networks whereby the GPS network is considered as a connected and directed graph with three components.In this algorithm the gross error detection is undertaken through loops of different spanning trees using the "Loop Law" in which the individual components Δ X, Δ Y and Δ Z sum up to zero.If the sum of the respective vector components ∑X,∑Y and ∑Z in a loop is not zero and if the error is beyond the tolerable limit (ε>w),it indicates the existence of gross errors in one of the baselines in the loop and therefore the baseline must be removed or re_observed.After successful screening of errors by graph theory,network adjustment can be carried out.In this paper,the GPS data from the control network established as reference system for the HP Dam at Baishan county in Liaoning province is presented to illustrate the algorithm. 展开更多
关键词 全球定位系统控制网 图论 过失误差 有向群 树形图 关联矩阵
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A New Algorithm of Roundness Error Separation Technique of Three-point Method
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作者 雷贤卿 李济顺 +3 位作者 薛玉君 马伟 崔凤奎 胡东方 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第2期141-145,共5页
Through the analysis of roundness error separation technique of three-point method and based on the invariability and periodicity of the geometrical characteristic of measured round contour, a new matrix algorithm, wh... Through the analysis of roundness error separation technique of three-point method and based on the invariability and periodicity of the geometrical characteristic of measured round contour, a new matrix algorithm, which can be used to solve directly the roundness of the measured round contour without Fourier transform, is presented. On the basis of the research and analysis of the rotation error movement which is separated by using the three-point method, a mathematical equation is derived, which can be used to separate the eccentric motion of least square center of measured round contour and the pure rotation motion error of spindle in rotation motion. The correctness of this method is validated by means of simulation. 展开更多
关键词 信息加工 三点方法 矩阵 偏心运动
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ACCURATE COMPUTATION FOR IRREDUCIBLE NONSINGULAR M-MATRIX
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作者 薛军工 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1995年第1期116-117,共2页
Computing the eigenvalue of smallest modulus and its corresponding eigneveclor of an irreducible nonsingular M-matrix A is considered, It is shown that if the entries of A are known with high relative accuracy, its ei... Computing the eigenvalue of smallest modulus and its corresponding eigneveclor of an irreducible nonsingular M-matrix A is considered, It is shown that if the entries of A are known with high relative accuracy, its eigenvalue of smallest modulus and each component of the corresponding eigenvector will be determined to much higher accuracy than the standard perturbation theory suggests. An algorithm is presented to compute them with a small componentwise backward error, which is consistent with the perturbation results. 展开更多
关键词 IRREDUCIBLE NONSINGULAR M-matrix BACKWARD error componentwise PERTURBATION
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ERROR ANALYSIS FOR SOLVING VANDERMONDE SYSTEM WITH SPECIAL POINTS
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作者 曲延云 蒋尔雄 薛军工 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2003年第1期111-120,共10页
The Bjorck and Pereyra algorithms used for solving Vandermonde systemof equation are modified for the case where the points are symmetricly situated aroundzero. The working operation is saved about half. A forward err... The Bjorck and Pereyra algorithms used for solving Vandermonde systemof equation are modified for the case where the points are symmetricly situated aroundzero. The working operation is saved about half. A forward error analysis is presentedfor the modified algorithms, and it's shown that if the points are situated in some order,the error bound are as good as Higham's result in 1987. 展开更多
关键词 线性控制系统 Vandermonde系统 VANDERMONDE矩阵 零点 误差分析
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