In transportation networks, a transshipment node with flow demands fails to conform to flowconservation, and can not be categorized to a source, a sink or an intermediate node.
运输网络中有流量需求的转运结点不遵从流量守恒条件，也不能按源、汇及中间结点归类。
2
The flowconservation law of belt drive is introduced and the conclusion that the tension difference between the tighten belt and the looser leads to speed difference is proved.
介绍了皮带流量守恒定律，根据此定律论证了皮带松紧边拉力差导致速度差这一结论。
3
Frequency control the use of fans, water pumps, type of machinery to carry out speed control method to regulate the flow of energy conservation, economic efficiency is very important significance.