First it needed a boundary structure, i.e., a cell membrane to distinguish it from the outside world.
首先它需要一个界面结构，即一个区分它和外部世界的细胞膜。
2
All objects belonging to the cell must be inside the cellboundary.
在单元内部所有的金属线都必须有单元边界。
3
After a cell is broken, the stress adjustments of the other cells in the system are obtained by finite element method using the broken cell as inner boundary.