对称

Lenses are optical elements with 2 refractive surfaces. These can be centered sphericalally, rotationally

这些透镜是有中心的，如球面的或旋转对称的，而不是非旋转对称的。

The detailed works are as follows: 1. Realization of numerical simulation for rotationally asymmetric sound absorbent structures by finite element method.

具体工作在如下两方面：(1)具有旋转对称腔体和非对称基材单元的水下吸声结构声学特性在数值仿真的实现。

The electronic structures of cluster Fe8 with D6h symmetry and Fe15 with Oh sysmmetry have been studied by MS-X method..The results show that(1 the exchange splittings of the d-band and the magnetic moments of the Fe-atoms are different in the two clusters;(2)the change distribution in both clusters is not uniform,showing that the electrons are transferred from peripheral atoms to inner atoms,and the spin-directionof the electrons transferred is in accordance with the symmetric characteristics...

用MS-Xα方法研究了Fe8原子簇（具有D6h对称）和Fe15原子簇的电子结构，结果表明：（1）两种原子簇中的Fe原子磁矩及其d能带中的交换劈裂性质互不相同；（2）两类原子簇中的电荷分布不是均匀的，电荷倾向于从外围原子向内部原子上转移，并且被转移电子的自旋方向与原子簇的对称性质密切相关。

We proved, under a geometric condition given by Capietto, Mawhin and Zanolin, the infinity and some dense distribution of even or odd symmetric subharmonics for the equation with oscillatory nonlinearity.

本文讨论了具有偶或奇对称性的Duffing方程，在由Capietto，Mawhin和Zanolin给出的几何条件下，我们证明了具有振动非线性的对称Duffing方程有无穷多个对称的次调和解，并且其次调和解具有某种稠密的分布。

The otherfaces of the building address the adjacent commercial precinct with lively asymmetry and transpositions of scale.

朝着市政中心的两个立面采用了对称的形式，另外两个立面用非对称和转化尺度的手法与附近商业建筑进行了对话。

The discrete-element modeling is a new dynamic modeling method in structural geology and geophysics research. The authors built a discrete element model to simulate the evolution of the fault system in active salt domes. Results show that the fault system undergoes three stages: symmetric deformation stage, asymmetric deformation stage, and complete fracture stage.

离散元模拟是构造地质地球物理研究中一种新的动力学模拟方法，作者通过构建离散元模型，模拟了主动底辟盐构造断裂系统的演化过程，结果表明，该断裂系统的发育主要经历了对称变形、不对称变形、整体破裂三个阶段。

Having or marked by bilateral symmetry.

左右对称的以或表现为左右对称的

For the foramen ovale in MRI, bilateral symmetry 13 cases(65%) and asymmetry 7 cases(35%);rotundum 8 sides(20%),ovale 32 sides(80%).

全部患者卵圆孔及棘孔在增强T1WI上为双侧显示，卵圆孔两侧对称13例(65%)，两侧不对称7例(35%)；呈圆形8例(20%)，呈椭圆形32例(80%)。

Fluctuating asymmetry, defined by random, stress-induced deviations from perfect bilateral symmetry, is an indication of the inability to buffer against developmental disturbances, such as poor early nutrition.

波动不对称是压力的随机性引发双侧完美对称偏离的现象，这是个体无力免受发展中不利因素侵害的一个标志。

Flatfish, such as the flounder, are among the few vertebrates that lack approximate bilateral symmetry (symmetry in which structures to the left and right of the body's midline are mirror images).

鲆鱼，例如比目鱼，是少数左右两侧不太对称的脊椎动物之一（左右两侧对称指的是身体中线左右两边的结构为镜象反射）。

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％。