查询词典 eigenvalue

Order determination is accomplished in two stages, i.e., the AR order is first determined by the minimum eigenvalue of overdetermined instrumental variable product moment and the MA order is then estimated by the minimum eigenvalues of a covariance matrix derived from the observed data.

该方法将ARMA模型的结构辨识分两步进行：首先利用超定辅助变量乘积矩(0IVPM)的最小特征值确定自回归部分的阶，然后利用协方差矩阵的特征值估计滑动平均部分的阶。

This paper elaborate the basis of theory of clustering analysis and PCA, Analyzed and compares several kind of more popular partitional clustering algorithms, then we propose a new clustering algorithm based on the largest or the second largest eigenvalue and principal component analysis.

本文首先是阐述了聚类分析以及主成分分析的一些理论基础，分析和比较了几类较流行的划分聚类算法，并在说明现有算法的不足的基础上提出了两类改进的聚类算法。

The perturbational reanalysis method of repeated eigenvalues and associated eigenvectors of the lineargeneralized eigenvalue problem is further investigated on the basis of the relevant results of previous stud-ies.

本文基于已有研究结果，进一步探讨了线性广义特征值问题的重特征值及其特征向量摄动重分析理论和方法，阐述了重特征值情形下摄动重分析方法的一些重要特点，完善了重特征值的特征向量的二阶摄动算式，并论证了重特征值摄动法与相异特征值摄动法之间的统一性。

Firstly, the high resolution pictures of dragonfly wings from sample tests were studied thoroughly, and the unique feature of the reticulate vein distribution and the variation of the vein sizes and the grid shapes in different zones were figured out;then several computational models based on a dragonfly wing were established by using ANSYS, and beam 189 and shell 93 elements were used respectively in modeling of the veins and the membrane so as to ensure the compatibility between the veins and the membrane at a deformed state;these models subject to uniform loading cases were analyzed respectively so as to explore the unique performances of the wing structure, furthermore, through eigenvalue spectrum analyses of these models, the special role of the pterostigma in eliminating or suppressing the wing quivering effect was also evaluated.

首先，对实验中获取的高清晰度的蜻蜓翅膀数码图片进行了细致地分析，找出了翅膀网状翅脉结构中翅脉的分布规律与尺寸变化、网格形状的差异及不同形状网格的分布等独特的结构特征；再利用ANSYS建立蜻蜒翅膀网状翅脉结构模型，采用三节点等参数梁元beam189模拟翅脉和八节点等参数曲壳单元shell93模拟翅膜，以满足翅脉和翅膜间的变形协调性要求；通过非线性数值分析，探索了蜻蜓翅膀网状翅脉结构在均布荷载作用下所具有的独特的结构性能；通过模态分析，揭示了翅膀前缘靠近翼尖附近的翅痣在翅膀消震减振中所发挥的作用。

With rotational invariance of circle, image was divided into different sectorial sub blocks in polar coordinates, and the sum of regional pixels was taken as sector eigenvalue. Then a normalized feature space by norming sector feature set was got.

以圆的旋转不变特性为基础，在极坐标下将图像分割为不同的扇形子块，并将各子块区域灰度和作为表示扇形子块的特征，然后对子块特征集进行归一化，所得的归一化扇形特征集作为特征选取的空间。

Singular linear systems; Iterative methods;AOR method; JOR method; Rank deficient least squares problems;Semiconvergence; Optimum parameters; P-cyclic matrix; Consistently ordered matrix; Preconditioning; Matrix pencil; Eigenvalue bounds; Support number

奇异线性方程组；迭代法；AOR 方法；JOR方法；亏秩最小二乘问题；半收敛性；最优参数；P-循环矩阵；相容次序矩阵；预处理；矩阵对；特征界；支撑数

P procedure. In our model, however, we have used a modified subband structure which is actually the solution of the eigenvalue problem in a 4×4 Luttinger-Kohn matrix.

而在我们的模型里面，我们使用了求解4×4 Luttinger-Kohn矩阵的特徵值的方法来得到修正过的次能带结构。

The results show that wet air reduces both fatigue life and strength with the influence-factor of 0.6059 and 0.8722, respectively. Wet air environment enlarges the dispersivity of fatigue life, therefore using the corrosion-influence-factor obtained by eigenvalue or mean value to predict the fatigue life with high reliability will cause an unconservative conclusion.

结果表明，潮湿空气环境显著降低了2024-T3铝合金的疲劳性能，潮湿空气环境对其疲劳寿命特征值和疲劳强度均值的影响系数分别为0.6059和0.8722；在潮湿空气环境中疲劳寿命的分散性变大，用疲劳寿命的中值或特征值得到的腐蚀影响系数进行可靠度95%的腐蚀环境下的寿命修正，将得到偏危险的结果。

Moreover, Arnoldi method was also applied to the generalized unsymmetric eigenvalue problem, which arised from the applying of BEM to the free vibration problem of elasticity.

此外，将Arnoldi法应用于由边界元法得到的非对称广义特征值问题，给出了这类特征值问题有效的减缩式求解方法。

The transforms introduced in this dissertation make it possible use eigenvalue method to investigate the generation of internal tides over finite topographies.

坐标变换将倾斜地形变换到了平底，同时也改变了强迫源强度的分布特征，使得变换之后强迫源强度的分布与原始分布有很大的不同。

The use of the web to spread fears that flicking the switch on the LHC could create a Black Hole that could swallow up the Earth particularly concerned him, he said.

他说，使用互联网散布恐慌说启动LHC会生成一个可能吞噬地球的黑洞的做法让他感到忧虑。

Not a single word have I written down.

我一个字也没有写下来。