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 共查询到19条相似文献,搜索用时 54 毫秒
1.
王华  杨一都 《数学杂志》2005,25(4):468-472
本文研究了有限元近似可计算的误差界,利用“二次插值过渡”方法,获得二维线性、双线性有限元和三维三线性有限元的新的插值常数估计值.理论分析和数值实验表明该结果是有效的,发展了P.Arbenz等人的工作.  相似文献   

2.
本文讨论机器具有准备时间的双目标平行机排序问题,目标函数为完工时间和最优条件下极小化最大完工时间.通过对SPT排序的性质的分析,给出了最优排序的下界.在此基础上证明了SPT排序的误差界为3/2,并且是紧界.  相似文献   

3.
一种新的Levenberg-Marquardt算法的收敛性   总被引:13,自引:0,他引:13  
杨柳  陈艳萍 《计算数学》2005,27(1):55-62
Levenberg-Marquardt方法是求解非线性方程组的重要算法之一,在本文中,我们针对奇异非线性方程组给出了Levenberg-Marquardt方法的一种新的参数迭代方法,即取μk=||J(xk)^TF(xk)||.我们证明了在弱于非奇异性条件的局部误差有界下,Levenberg-Marquardt方法仍具有局部二次收敛速度.数值实验表明算法是很有效的。  相似文献   

4.
本文我们讨论了矩形域上带连续边界条件的一类多元散乱数据最优插值。给出了某些情形插值的误差估计,误差估计表明在某些点上还具有超收敛性。  相似文献   

5.
研究了B-Nekrasov矩阵线性互补问题的含有参数误差界的最优值问题,利用函数的单调性,在_0_(i_1)···_n···_(i_(n-1))≥0且0_n1的情况下,得到了该误差界的最优值.  相似文献   

6.
本文发展Stokes问题的一个四变量杂交-混合变分方程:应力-速度-压力-拉格朗日乘子.然后发展其有限元方法:对应四变量分别用间断型Raviart—Thomas最低阶元,分片常数元,连续线性元和连续线性元的迹空间.我们获得了稳定性和最优误差界.通过后处理办法,我们得到一个适合于计算的速度-压力格式,该格式可视为“Mini”元方法的一个变形(本文格式中引入了局部投影算子).然而,本文格式关于压力具有“超收敛”结果:得到了压力关于H^1-范的误差界O(h).  相似文献   

7.
考虑了伪凸集值映射的误差界.证明了对于伪凸集值映射,局部误差界成立意味着整体误差界成立.通过相依导数,给出了伪凸集值映射存在误差界的一些等价叙述.  相似文献   

8.
刘毅  高磊 《应用数学》2023,(1):1-15
本文研究S-Sparse Ostrowski-Brauer (S-SOB)矩阵线性互补问题误差界的估计问题.利用矩阵不等式放缩技术及S-SOB矩阵逆矩阵无穷大范数,获得S-SOB矩阵线性互补问题的误差界,该界仅依赖于S-SOB矩阵的元素.在此基础上,给出S-SOB-B矩阵线性互补问题的误差界,并从理论上证明所给误差界在一定条件下优于García-Esnaola等(2009)和LIU等(2021)所给的结果.最后,通过数值算例进一步阐明了结果的有效性.  相似文献   

9.
佟毅 《工科数学》1999,15(2):74-76
本研究一类单相关回归模型的效率及其应用,证明了对单相关回归模型的任一可估函数c'β=c’(X’X)-X’Y的最小二秉估计(LS)都是最佳线性一致无偏估计(BLU).给出了这类摸型的均方误差比效率的下确界(infpMSEE).同时研究了用最小二乘估计代替最佳线性一致无偏估计时应注意的问题.  相似文献   

10.
一个有效的预测模型应当是无偏的,即预测误差均值为零。一旦出现偏差,就必须对预测模型作出调整、修正。为判断预测模型的有效性,本文讨论了两种预测误差跟踪信号,以及它们之间的关系,并在此基础上作出了改进.最后,用了一个实例说明其应用.  相似文献   

11.
This paper studies the existence of a uniform global error bound when a convex inequality g 0, where g is a closed proper convex function, is perturbed. The perturbation neighborhoods are defined by small arbitrary perturbations of the epigraph of its conjugate function. Under certain conditions, it is shown that for sufficiently small arbitrary perturbations the perturbed system is solvable and there exists a uniform global error bound if and only if g satisfies the Slater condition and the solution set is bounded or its recession function satisfies the Slater condition. The results are used to derive lower bounds on the distance to ill-posedness.  相似文献   

12.
In this note,we consider the backward errors for more general inverse eigenvalus prob-lems by extending Sun‘‘‘‘s approach.The optimal backward errors defined for diagonal-ization matrix inverse eigenvalue problem with respect to an approximate solution,and the upper and lower bounds are derived for the optimal backward errors.The results may be useful for testing the stability of practical algorithms.  相似文献   

13.
The Bezout Number for Piecewise Algebraic Curves   总被引:1,自引:0,他引:1  
The computation of the Bezout number, the maximum number of intersection points between two piecewise algebraic curves whose common points are finite, is considered. A piecewise algebraic curve is a curve determined by a bivariate spline function. It is found that the maximum number of intersections depends not only on the degrees and the differentiability of the spline functions, but also on the structure of the partition on which the spline functions are defined.  相似文献   

14.
In this paper, by using the explicit expression of the kernel of the cubic spline interpolation, the optimal error bounds for the cubic spline interpolation of lower soomth functions are obtained.  相似文献   

15.
Suppose Ax = b is a system of linear equations where the matrix A is symmetric positive definite and consistently ordered. A bound for the norm of the errors k = xx k of the AOR method in terms of the norms of k = x kx k–1 and k+1 = x k+1x k and their inner product is derived.  相似文献   

16.
设X为一复域C上的Banach空间,设T:X→X为一有界线性算子,其指标为k且R(Tk)闭.记T的Drazin逆为TD.设T=T+δT,则在一定条件下,TD有简明分解式TD=TD(I+δTTD)-1=(I+TDδT)-1TD,从而导出了相对误差‖TD-TD<  相似文献   

17.
The quadratic discriminant function is often used to separate two classes of points in a multidimensional space. When the two classes are normally distributed, this results in the optimum separation. In some cases however, the assumption of normality is a poor one and the classification error is increased. The current paper derives an upper bound for the classification error due to a quadratic decision surface. The bound is strict when the class means and covariances and the quadratic discriminant surface satisfy certain specified symmetry conditions.  相似文献   

18.
We give a lower bound for a quality measure of rank 2 lattice rules which shows that an existence result of Niederreiter is essentially best possible.

  相似文献   


19.
The paper is devoted to studying the Hoffman global error bound for convex quadratic/affine inequality/equality systems in the context of Banach spaces. We prove that the global error bound holds if the Hoffman local error bound is satisfied for each subsystem at some point of the solution set of the system under consideration. This result is applied to establishing the equivalence between the Hoffman error bound and the Abadie qualification condition, as well as a general version of Wang &; Pang's result [30], on error bound of Hölderian type. The results in the present paper generalize and unify recent works by Luo &; Luo in [17], Li in [16] and Wang &; Pang in [30].  相似文献   

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