对于系统，翻版的模拟是在控制图中添加一个创建循环的边，而不仅仅是一个附加节点。
For systems, the analogue of a face-lift is to add to the control graph an edge that creates a cycle, not just an additional node.
The greatest glory in living lies not in never falling, but in rising every time we fall.
电池革命才刚刚开始。