查询词典 numerical algorithm

Numerical experiments show that the new algorithm is not only an all-purpose algorithm, but also a high-performance algorithm with better results than others.

数值实验表明，新算法不仅是一种通用的算法，而且与已有算法的计算结果相比，其解的精确度也最好。

In this paper, an extended divide and conquer algorithm is intended proposed, which is for solving the real symmetric band generalized eigenvalue problem under distributing environment Eigenvalue partition theorem is presented and proved Based on divide and conquer by extension, this algorithm computes generalized eigenpaires of symmetric band matrix pencil by bisection and generalized Rayleigh quotient iteration Theoretic analysis and numerical results show that this algorithm is better than the classic software package LAPACK when bandwidth is small and the scale is large Combined with multisection, which has good parallelism, it got good effects under distributed environments

提出了分布式环境下计算对称带状广义特征值问题的一种扩展分治算法，给出了特征值分割定理及其证明算法在扩展分治的基础上，利用二分压缩结合广义Rayleigh商迭代计算广义特征对理论分析和数值实验表明，对于窄带宽大规模的广义特征值问题，该分治算法明显优于LAPACK软件包结合并行性好的多分法，在分布式环境下获得了很好的并行效果1 引言本文研究了对称带状广义特征值问题Ax =λBx ( 1)的并行计算，其中，A ，B均为半带宽为r的n阶实对称带状矩阵且其中之一是正定的本文总假设B是正定的求解此问题有两种传统方法，第1种方法是通过计算矩阵B的Cholesky分解，将问题( 1)转化为标准特征值问题[1～3] ，进一步

The coordinate transformation and numerical integration was executed on the discretized tetrahedral elements based on which the 3-D MT vector-finite element method was implemented. A whole computation framework for 3-D vector-finite element method with unstructured mesh was given. Based on this some typical models were tested which has demonstrated that our algorithm could distinctively avoid problems caused by the fake solution and both the accuracy and efficiency were enhanced which made our algorithm has a bright future for further application.3. According to theory of Sobolev vector space and the discretization of Helmholtz space, the error estimate which was suitable for 3-D MT vector-finite element modeling was deduced by which the procedure of adaptive technique was guaranteed.4. Based on the fully unstructured tetrahedralization and optical strategy, the 3-D magnetotelluric h-adaptive vector-finite element method was presented through combining the error estimate. With this work, the accuracy and creditableness for 3-D MT complicatedly modeling was guaranteed.5. The 3-D magnetotelluric h-adaptive vector-finite element algorithm with unstructured mesh was implemented.

针对非结构化的四面体单元，采用坐标变换和数值积分方法，实现了MT三维矢量有限单元分析，建立起基于非结构化网格的三维MT矢量有限元计算流程，并对典型模型和国际标准电磁模型进行了数值模拟，结果对比和分析表明，基于非结构化网格的三维MT矢量有限元不仅消除了节点型有限元的伪解，而且具有很高的计算精度和速度，有广阔的应用前景。3、根据Sobolev函数的向量空间和Hemlholtz空间的分解，推导出基于残差的三维大地电磁矢量有限元后验误差估计公式，为三维大地电磁自适应矢量有限元数值模拟的实现奠定了基础。4、在完全非结构化四面体单元剖分及优化基础上，结合三维大地电磁矢量有限元后验误差估计公式，提出了基于非结构化网格的三维大地电磁h-型自适应矢量有限元计算策略，保证了对复杂大地电磁模型数值计算的精度和可靠性。5、实现了基于非结构化网格的三维大地电磁h-型自适应矢量有限元计算流程，对典型模型和国际标准电磁模型进行了数值模拟。

For overlapping domain decomposition method, we prove the geometric convergence for continuous algorithm in the sense of energy norm by means of projection theory, analyze the convergence rate of the algorithm in detail. And we also discuss the discretization of the algorithm and its finite element implementation. Some numerical experiments are also given.

对重 叠型区域分解算法，利用投影理论，证明了连续型算法在能量模意义下的几何收敛性，详细地分析了算法的收敛速度，也讨论了算法的离散化及有限元处理，并给出了相应的数值实验。

Numerical experiments were conducted on real AVIRIS data to validate the effectiveness of the proposed algorithm. The detection results were compared with those detected by the classical RX algorithm and KRS which did not suppress the backguound information. The results show that the proposed algorithm has better detection performance, lower false alarm probability and lower computational complexity than other detection algorithms.

为了验证算法的有效性，利用真实的AVIRIS数据进行了实验研究，并与经典RX算法、未抑制背景的特征空间核RX算法的检测结果相比较，结果表明基于背景残差数据的检测算法具有良好的检测性能和较低的虚警，而且运算复杂度较低。

This article introduced the C # language used to generate a straight line of three commonly used method: numerical differentiation, in line and stipple Bresenham algorithm, and then introduced the mid-point algorithm Circle, the polygon algorithm.

本文主要介绍了用C＃语言生成直线的三个常用算法：数值微分法、中点画线法和Bresenham算法，然后介绍中点画圆算法、多边形的生成算法。

Thirdly, the principal curve and polygonal line algorithm are introduced, and an implementation of polygonal line algorithm based on Quasi-Newton numerical optimization is illustrated. The simulation results show that when this algorithm isused in the detection of curvilinear defects on wafer map, it can converge fast, compute accurately and meet the demand of application of defects pattern analysis, and with the number of line segment increasing, the polygonal line will approximate to the Kegl principal curve.

研究了主曲线、多边形线算法，提出用多边形算法识别弧状缺陷想法，讨论了用拟牛顿法实现该算法的解决方案，针对硅片缺点模式分析中常出现的弧状缺陷，采用该算法进行检测分析，实验结果表明这种算法快速准确，当线段个数或最小距离平方期望值达到一定门限值后，多边形线就已经能够描述弧状缺点集的形状，随着线段个数增加，最小距离平方期望值还在不断下降，最终会收敛到Kegl主曲线。

In this paper, the maximum likelihood algorithm with process and measurement noise for nonlinear continuous-discrete system given by Jategaonkar and Plaetschke is improved in two aspects: 1 to avoid the disadvantages of sensitivities computation by common finite-difference method, in which the perturbation sizes should be selected optionally, an improved finite-difference method with best perturbations, is presented. 2 to improve the numerical stability of Jategaonkar's algorithm, maximum likelihood algorithm with fast triangular square-root decomposition filter is given.

摘要对Jategaonkar等人给出的同时计及过程及观测噪声的非线性连续-离散系统的极大似然算法从两个方面进行了改进：1给出了计算灵敏度的最佳摄动有限差分算法，避免了普通有限差分法计算灵敏度矩阵时需人为选择参数摄动量大小而带来的缺点；2给出了具有快速三角化平方根滤波的极大似然算法，提高了原算法的数值稳定性。

To obtain efficient survivability, this paper presents a novel restorable lightpath selection algorithm based on the automatically switched optical network frame. A numerical simulation is made in term of this routing selection algorithm. The result shows that the traffic has an obvious balancing trend; the block probability of connection requests has been reduced. At the same time, this algorithm has an excellent performance on bandwidth utility and sharing of the restoration resources.

摘要为了获得高效的网络生存性能，基于自动交换光网络的框架，该文提出了一种新型的可恢复路径选择算法-联合可变权重可恢复路径选择算法，并进行了数值仿真分析，仿真结果表明，此恢复路径选择算法具有明显的业务量均衡能力，并降低了动态连接请求的阻塞概率，同时具有良好的带宽利用率和恢复资源共享效率。

In this paper we propose a new image reconstruction algorithm for electrical impedance tomography-Quasi-Newton algorithm, based on modified Bk. Numerical tests were made to verify the effectiveness of this algorithm.

本文提出了一种新的电阻抗成像图像重建算法—基于修正Bk的拟Newton类算法，并通过数值试验验证了该算法的有效性。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。