Two-and three-dimensional hydrodynamic computer codes have been applied to the study of the early phases of the collapse of a gas cloud.

二维和三维流体力学计算机程序，已用于研究气体云的早期坍缩。

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In time and space, the whole process of karst collapse can be divided into two phases: inter collapse and surface collapse in term of the formation of the critical soil hole.

以临界土洞为界，岩溶塌陷的整个发育形成过程从时间和空间上划分为内部塌陷和地表塌陷两个密不可分的阶段。

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