This variation has infinite solution. It is only applicable in the invariantstate of ventilation network structure and parameters.
这种变换存在着解的无穷性,并且仅适用于通风网路的结构和参数不变的状态。
2
With the bridge, our invariant was that the bridge would always be parented off of a point in server state space and would be the one operation needed to transform incoming server operations.