查询词典 quinoid form

Principal curvatures and principal directions are obtained by computing in closed form the eigenvalues and eigenvectors of certain 3×3 symmetric matrices defined by integral formulas, and closely related to the matrix representation of the tensor of curvature.

通过计算3×3对称矩阵的特征值和特征向量可以得出主曲率和主方向，而该对称矩阵是由积分公式定义并且与曲率张量的矩阵表达密切相关。

This paper proposes a robust filter function, called trilateral filter function, to filter the noises in the domains of surface curvature, normal and position at each sample point while the local surface is fitted in a quadratic form. By optimizing the filtering result of curvature tensor, our approach is capable of preserving the feature on the target model.

通过在扫描模型每个采样点处拟合一个二次型曲面，设计了一个鲁棒的滤波函数--三边滤波函数；应用该函数分别对模型表面上每个点的法线、曲率和位置进行滤波；通过对曲率的滤波结果进行优化，可有效地保持三维模型表面上的特征。

The shape-form analysis and load analysis were done by nonlinear FEM. On the basis of surface FEM grid nodes, geometry property research of structure curved surface was progressed, including normal vector, GAUSS curvature, mean curvature and principal direction vector. In this process, the approximate expression of surface didn't need to he known.

采用非线性有限元法进行了膜结构的形态分析和荷载分析，得到了曲面有限元网格；通过离散微分几何方法，研究了薄膜结构曲面的几何性质，包括曲面的法线向量、高斯曲率、平均曲率和主方向矢量，避免了复杂的曲面拟合过程。

Research results show that: 1 The FLSD is basically path independent whether is for steel or for aluminium; 2 Shape of the forming limit curve in stress space is sensitive to the type of material model used in transformation form FLD to FLSD; 3 the anisotropy of sheet metal has considerable influence on the FLSD; 4 The application of the FLSD in sheet metal processes optimization was considered to be effective and more precise.

钢板和铝板应该分别采用不同的材料模型进行转换。3）板料各向异性性能对板料成形极限有影响，在使用FLSD时应该考虑板料的各向异性情况；4）FLSD在应用于多道次成形零件的有限元分析时，由于其具有的与加载路径无关的特点，因此比通常用的FLD更加准确可靠。本课题的研究为以后在板料成形仿真中，使用应力成形极限曲线代替应变成形极限曲线，提供了理论和试验依据。

And the most important problem of the line form is curved line.

作为造型艺术，绘画中的形，尤其是线形的问题一直倍受关注；而线形中的曲线问题尤为引人注目。

Why they can use the curved line form to create such different expressform?

为什么他们在绘画中用曲线创造出了如此多的不同的表现方式？

The torch is of a curved surface form, with etching and anodizing being used during its production.

火炬传递是一个曲面的形式，与蚀刻和阳极氧化被用来在其生产的。

It is obviously impossible to form a mental picture of what a curved three-dimensional space would look like.

要在我们脑海中形成一幅弯曲的三维空间画面是怎么样的，很显然这是不可能的。

Based on the Navier-Stokes equations in conservative form derived with respect to nonorthogonal curvilinear coordinates and nonorthogonal velocity components, the numerical method for solving 3D viscous flow has been discussed.

本文基于非正交曲线坐标与相应的非正交速度分量下导得的守恒型N—S方程，讨论了求解三维粘性流动的数值方法，计算中显式时间推进算法与Baldwin—Lomax湍流模型被采用，应用本工作发展的程序，作为算例计算了一个沿径向非等截面环形叶栅的三维粘性流场，得到了诸如三维压力分布，总压损失分布以及十分清晰的二次流动图景等丰富的流场信息。

The two-parameter negative exponential form could bump regression analysis degree of fitting up Least square curvilinear regression method was considered as the most conformable regression-type analysis.

回归分析的方法使用最小二乘法曲线回归方法。

These rules reflect some inherent feature of self and nonself, and they are the basic detection criterion of GECISM.

这些规则反映了"自我"和"非我"的内在特征，是GECISM进行"非我"检测的判据。

Until today, the media from China and the outside world still uses the term "Post 89". Regardless to whether it is for commercial gimmick or convenience, everybody still remember "Post 89", a term which carries a strong Cantonese accent.

时至今日，国内外艺术媒体还是在沿用&后八九&这个称谓，不管当初是为了商业噱头还是容易上口好记，反正大家现在是记住了&后八九&这个广东口音很重的词。