在铁路线路三维场景中，存在着大量的对称物，如树木、亭子、栏杆等，大部分对称物都属于复杂地物。

There are a lot of symmetry objects in the railway 3d sight, such as tree, georgette, and balustrade and so on.

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第一部分对动态球对称黑洞的霍金效应进行了研究；第二部分讨论了动态轴对称黑洞的霍金效应。

The first one is about the Hawking effect of a dynamical spherically symmetric black hole; the second one is for an axisymmetric dynamical black hole .

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