*5.1. Objective*

The link betweenness is the sum of the ratio of the shortest path number to the shortest path number between all the two nodes in the network. It characterizes the influence of nodes or edges on the whole network. The minimum number of edges is the smallest, which can effectively ensure that the shortest path of the network is small (Equation (8)). This goal indirectly shortens the total travel

time of passengers and ensures the efficiency of the network. In Equation (8), *n* is the number of arcs between (*No*, *Nd*); *Bi* refers to the betweenness of arc *i*; and *ri* is the resistance of arc *i*.

$$\text{minim}Z = \sum\_{i=1}^{n} B\_i r\_i \tag{8}$$
