查询词典 algebraic variety

There are three main methods in face localization: localization according to face outline, localization according to complexion and localization according to templates constructed by some standard sample images. As to feature extraction, it can be divided into two parts because face features can be divided into geometrical features and algebraic features. While extracting geometrical features, the features of eyes, nose, mouth, eyebrows can be gained by some image processes: binary, sharpen, smooth, projection, calculating gradient and so on. In order to extract algebraic features, we can do some mathematical transformation for the digital images such as singular value decomposition, K-L transformation.

在人脸检测部分，目前存在的方法有利用人脸的几何轮廓进行检测、利用人脸的肤色信息进行检测、构造标准人脸模板进行匹配检测等等；在人脸特征提取部分，可以用一些图像处理的方法如投影、二值化、求梯度图像等提取人脸中各特征器官如眼睛、鼻子、嘴巴等的几何特征，另外也可以借助于数学变换，求取人脸图像的一些代数特征，如对图像进行奇异值分解，以奇异值代表图象的特征，或对图像进行K-L变换，以图像在构造的特征空间上的投影系数作为图像的特征等；在识别部分，可以通过距离度量或相似度来判断输入图像与样本图像的匹配程度，还可以通过神经网络方法进行人脸的识别。

Based on the transfinite interpolation theory, an improved algebraic grid generation method is presented in this paper. Our improvements of existing algebraic grid generation method include:(1) orthogonality control, which greatly improves grid orthogonality adapted to viscous flow calculation;(2) weighted average smoothing, which efficiently handles with grid intersection due to concave corner existence;(3) normal vector control, which adjusts grid smoothing near convex corner.

基于无限插值理论，引入本文提出的网格正交控制、物面法向量控制、加权平均光顺措施，给出了一种改进的空间网格生成方法，有效克服了传统无限插值网格生成方法在复杂外形网格生成方面的缺陷，有效改善了网格的法向疏密性、贴体性及周向网格的均匀性，对真实飞行器部件网格生成非常迅速。

The formulation of power system transient stability preventive control based on optimal power flow is presents in this thesis, in which multicontingency is considered. The infinite dimensions nonlinear optimization problem in which differential-algebraic equations are existed is changing into finite dimensions difference-algebraic equations by implicit trapezoid method.

建立了基于最优潮流的电力系统暂态稳定预防控制模型，通过隐式梯形法将含有发电机动态微分-代数方程和暂态稳定约束的无限维优化问题转换成有限维的常规静态最优潮流问题。

The "divide and conquer" strategy is used to improve the key steps of the undetermined coefficient algorithm for constructing polynomial conservation laws of nonlinear DDEs, so the calculation complexity problem caused by the dramatic increase of redundancy is solved. Furthermore, Wu\'s elimination method is applied to solve the obtained nonlinear algebraic equations thus to get a more efficient algebraic algorithm.

本文从微分方程的标度变换出发，利用"分治"策略改进了构造非线性DDE守恒律待定系数算法中的关键步骤，有效解决了因冗余项急剧增加引起的中间计算过程膨胀问题，并将吴消元法应用到非线性代数方程组的求解上，从而给出了一个更高效的代数算法。

So, in this paper, a circular cavity witha large radius is used to replace the straight boundary of thehalf space, then the half space problem can be changed tothe scattering problem of two circular cavities to the steadyincident P-wave . Having the aid of the mature cylinderfunction theory, the general solutions of the wave functionscan be given, and an infinite linear algebraic equations ofthe unknown coefficients in the wave functions can be gottenwith the boundary conditions and the Fourier complex seriesexpansion technology, the infinite linear algebraic equationscan be approximately solved by the finite trunction withsatisfying some definite precision, at the basis of thissolution of the equation, the variations and the lay-outs ofthe DSCF at the circular cavity boundary vs. the differentincident angles, the different embedded depths of thecircular cavity as well as the different dimensionless wavenumber of the incident P-wave.

为此，本文采用一个半径很大的圆孔来代替半空间的直边界，将该半空间问题转化为一无限大空间中两个圆孔对稳态P波的共同散射问题，借助于成熟的柱函数理论，通过写出问题波函数的一般形式解，利用问题的边界条件，并采用复数傅立叶级数展开技术将其化为一个仅包含问题波函数中未知系数的一无穷线性代数方程组，在满足一定计算精度的前提下，通过有限项截断进行近似求解，进而讨论了圆孔边界处的动应力集中系数随不同入射角、不同的圆孔掩埋深度、入射波的不同无量纲波数以及介质的泊松比变化和分布情况。

Under the condition of knowing zero eigenvalue algebraic multiplication ,the authors have discussed the use and necessary relationship between matrix zero eigenvalue algebraic multiplication and matrix rank.

在已知零特征值代数重数时，给出了矩阵零特征值代数重数与矩阵秩之间的内在必然联系，及其一般应用。

Algebraic ≈ algebraic , algebraical

adj。代数的，关于代数学的

Since the algebraic limit G of discretegroup sequence 〓 may be nondiscrete and nonelementary,we must add someconditions for the study of the relationship between the group sequence 〓 of〓 and its algebraic limits.

在第一章中，我们研究〓上的〓变换群集〓和其代数极限G的关系。

With the frequency and mode shape being regarded as functions of damage parameters, the overdetermined algebraic equations with damage parameters as unknowns can then be constructed by differentiating frequency and mode function on the basis of structure mode finite element formula, the damage parameters of which are obtained via Taylor expansion. The whole damage parameters can be found via solving the algebraic equations.

本方法从结构模态有限元算式出发，把频率和振型看作损伤参数的函数，经过泰勒展开获得频率、振型对损伤参数的一阶偏导数，然后构造以损伤参数为未知量的超定线代方程组，求解得到全部损伤参数值。

Some results of algebraic attacks on stream ciphers are summarized and algebraic attacks on nonlinear combiners are ...

本文总结了流密码代数攻击的一些已有结果，对非线性组合生成器的代数攻击做了较为详细的讨论。

Liapunov—Schmidt method is one of the most important method in the bifurcation theory.

Liapunov—Schmidt方法是分叉理论的最重要方法之一。

Be courteous -- even when people are most discourteous to you .

要有礼貌──即使当別人对你最不礼貌的时候。