对称

In Laplace space, the exact element stiffness matrix of the axial, torsional and bending vibrations of cone-shaped and symmetrical closed thin-walled bars are derived. By use of variation principle, the element stiffness matrix of the coupling vibrations of an asymmetrical closed thin-walled bar is also given.

在拉氏空间中导出了锥形杆件和对称闭口薄壁杆件的轴向、扭转和弯曲振动的精确单元刚度矩阵，应用变分原理也给出了非对称闭口薄壁杆件耦联振动的单元刚度矩阵。

The parametic geometric feature include standard spur gear , helical gear, symmetrical tooth ,asymmetric tooth, double involute gear with ladder shape teeth, and Max-supporting quadruplet involute gear with four independent pressure angles with Ladder shape teeth.

支持的形状包括直齿，斜齿，对称齿形，不对称齿形，分阶齿。最高支持到具有4个独立压力角的齿轮副的生成。

The recognizability of the face is then defined as the function of the face size and the relative locations of eyes and mouth.

第四个部份，以两眼和嘴巴形成的三角形、方向的对称度、区域灰阶值的对称程度，来区分人脸的转向为三大类：正脸、有转动的脸和非正脸。

On the rhombohedron face {1011}, Dauphine twinning showed different shapes of etching pits between individuals, because rhombohedron positive form {1011} and negative form {0111} appeared on both sides of twin partition line, while Brazil twinning showed symmetry plane between the irregular triangle etching pits of individuals. On the trigonal prism section 11(average20, Dauphine twinning showed different shapes of etching pits between individuals, because trigonal prism positive form {1120} and negative form {2110} appeared on both sides of twin partition line, while Brazil twinning should show symmetry plane between the ellipse or quadrilateral etching pits of individuals, which was not observed.

菱面体{1010}面上存在道芬双晶处，道芬双晶双晶缝合线两端分别是菱面体正形、菱面体负形出露处，导致蚀坑形状不同；菱面体{1011}面上存在巴西双晶处，不规则三角形蚀坑形态的方位关系为对称面关系；三方柱切面{1120}面上存在道芬双晶处，道芬双晶双晶缝合线两端分别是三方柱正形、三方柱负形出露处，导致蚀坑形状不同；三方柱切面{1120}面上存在巴西双晶处，椭圆形或四边形蚀坑方位应为对称面关系，但实验中未见到。

Nucleoneffective interactions in the RMF are extracted by reproducing the properties ofsymmetric and asymmetric nuclear matter in the DBHF calculation. It is found thatthe properties of finite nuclei are depicted satisfactorily by those effective interactions.

用DBHF计算的对称和不对称核物质中核子自能或核子平均结合能在RMF下得到的同位旋相关的核子有效相互作用可以很好地描述有限核的性质。

It is recognized by the symmetrical rosette (hair radiating symmetrically from a center) and erect ridge patterns on its body and head.

它是公认的对称花环（头发从一个中心辐射对称）和竖脊模式，其身体和头部。

Synchronously rotating with the source voltage vector,the harmonics and reactive currents can be detected easily and rapidly.

目前对无功、不对称和谐波电流的检测和计算方法大多是针对三相对称正弦电源系统。

Based on this, convert the matrix equations problem for row symmetric matrices into ordinary matrix equations problem, the scale of converted matrix equations problem is half of that for the original problem.

在此基础上，将行对称矩阵方程组问题转化为一般的矩阵方程组问题，转化后的一般矩阵方程组问题的规模是原行对称矩阵方程组问题的一半。

In Chapter 3, we discuss the synchronization of coupled dynamical systems on condition that the external coupling matrices are n × n irreducible symmetric real matrices with zero row sum and nonnegative off-diagonal elements and internal coupling matrices are m × m asymmetric matrices.

在第三章我们讨论了耦合动力系统中，当外部耦合矩阵是n×n阶实对称不可约，行和为零且对角线以外的元素非负的矩阵，内部耦合矩阵是m×m阶非对称矩阵时耦合系统的同步问题。

The characteristic vector of the real symmetric matrix should be found out, which is orthogonalized and normalized to a standard orthogonal base and is used as row vector to construct the transformation matrix P, so the P~(-1)AP can be made into diagonal matrix.

实对称矩阵A经相似变换P-1AP可化为对角矩阵，在x =Py 下，不一定能化A的二次型为标准型；应寻求对称矩阵A的特征向量，将其正交化并单位化作为标准正交基，作为列向量构造变换矩阵P，可使P-1AP=Λ为对角阵，在x =Py 下，要将二次型化为标准型，且二次项系数即为对角阵Λ主对角线上元素。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。