在圆环中只有两个自旋粒子时，外加磁场大于某个阈值时，一对自旋粒子之间才能产生纠缠，而且纠缠是时间的周期性函数。

For a ring of two spins, the entanglement between the two spin particles can be created and is a periodic function of time when the external magnetic field is greater than a critical value.

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本文提出了以相关理论为基础，以图象中圆环参数自相关函数的最大值及互相关函数的最大值旋转不变为特征的图象匹配方法。

This paper presents a match method for letter images based on the coherence theory and properties which the maximum correlative values of the ring-data, however to rotate, are constant.

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如果用这种新的形状函数，则由此计算求得的刚度矩阵，不论三角圆环有限元的位置是否靠近轴线。

The calculated rigidity matrix is convergent everywhere, including these triangular toroidal element closed to the symmetrical axis.

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