## 3 Case Study
### Building RSCN  
At the station shown in Figure 2 and Table 1, when handling the IG arrival routes from Beijing direction, the train can reach the destination via four possible routes. The nodes traversed by each route are as follows:  
* \(\mathrm{IAG}\to 1\)-7 DG \(\to\) 11-23 DG \(\to\) 29-31 DG \(\to\) 55-61 DG \(\to\) IG;
* \(\mathrm{IAG}\to 1\)-7 DG \(\to\) 3-5 DG \(\to\) 15 DG \(\to\) 17 DG \(\to\) 37-47 DG \(\to\) 25-43 DG \(\to\) 57-59 DG \(\to\) 55-61 DG \(\to\) IG;
* \(\mathrm{IAG}\to 1\)-7 DG \(\to\) 11-23 DG \(\to\) 25-43 DG \(\to\) 57-59 DG \(\to\) 55-61 DG \(\to\) IG.  
Based on the definition of the RSCN and Equations (1) and (2), the RSCN can be established by representing the sequential relationships between track sections in the routes. Similarly, the topology network for this station can be constructed separately using the train routes table, extended routes table, and shunting routes table, as shown in Figure 3.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Route Type** & **Direction** & **Start** & **End** & **Track Sections** \\ \hline \multirow{8}{*}{Train Routes} & Arrival/Down & IAG & IG & IAG, 1–7 DG, 11–23 DG, 29–31 DG, 55–61 DG, \\  & Arrival/Down & IAG & IG & IAG, 1–7 DG, 3–5 DG, 15 DG, 25–43 DG, 57–590 DG, 55–61 DG, \\  & Arrival/Down & IAG & IG & IAG, 1–7 DG, 3–5 DG, 15 DG, 17 DG, 37–47 DG, 25–43 DG, 57–59 DG, 55–61 DG, \\  & Arrival/Down & IAG & IG & IAG, 1–7 DG, 11–23 DG, 25–43 DG, 57–59 DG, 55–61 DG, \\  & Arrival/Down & IAG & IG & IAG, 1–7 DG, 11–23 DG, 25–43 DG, 57–59 DG, 55–61 DG, \\  & Arrival/Down & IAG & IAG & IAG, 1–7 DG, 11–23 DG, 29–31 DG, 27–33 DG, 51 DG, 11–23 DG, 29–31 DG, 55–61 DG, \\  & Arrival/Down & IAG & IIIG & IAG, 1–7 DG, 11–23 DG, 29–31 DG, 55–61 DG, \\  & Arrival/Down & IAG & IIIG & IAG, 1–7 DG, 11–23 DG, 29–31 DG, 55–61 DG, \\  & & & & 57–59 DG, IIIG \\  & & & & \\  & & & & \\  & & (175 train routes in total) & & \\ \hline \multirow{8}{*}{Extended Routes} & SI Signal to Pull-out Tracks & 55–61 DG & D7G & 55–61 DG, 57–59 DG, 25–43 DG, 37–47 DG, 17 DG, 13 DG, D7G \\  & SI Signal to XD Signal & 55–61 DG & IIIAG & 55–61 DG, 57–59 DG, 25–43 DG, 15 DG, 3–5 DG, \\  & SI Signal to X Signal & 55–61 DG & IAG & 55–61 DG, 29–31 DG, 11–23 DG, 1–7 DG, IAG \\  & SI Signal to XF Signal & 55–61 DG & IIAG & 55–61 DG, 29–31 DG, 27–33 DG, 21 DG, 9 DG, \\  & & & & \\  & Routes & SI Signal to Locomotive Track & 55–61 DG & D9G & 55–61 DG, 29–31 DG, 27–33 DG, 21 DG, 19 DG, \\  & & & & D9G \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\  & & & (18 extended routes in total) & \\ \hline \multirow{8}{*}{Shunting Routes} & D1 Signal to D11 Signal & 1–7 DG & 3–5 DG & 1–7 DG, 3–5 DG \\  & D1 Signal to D21 Signal & 1–7 DG & 11–23 DG, 1–7 DG, 11–23 DG & 1–7 DG, 11–23 DG \\ \cline{1-1}  & D1 Signal to D35 Signal & 1–7 DG & 25–43 DG & 1–7 DG, 11–23 DG, 25–43 DG, 37–47 DG \\ \cline{1-1}  & D1 Signal to D37 Signal & 1–7 DG & 49 DG & 1–7 DG, 11–23 DG, 25–43 DG, 37–47 DG, 49 DG \\ \cline{1-1}  & D1 Signal to S5 Signal & 1–7 DG & 37–47 DG & 1–7 DG, 11–23 DG, 25–43 DG & 37–47 DG \\ \cline{1-1}  & Routes & D3 Signal to D21 Signal & 3–5 DG & 11–23 DG & 3–5 DG, 1–7 DG, 11–23 DG \\ \cline{1-1}  & & & & \\  & & & & \\  & & & (204 shunting routes in total) & \\ \cline{1-1}  & & & & \\ \hline \end{tabular} (Additionally, it also includes combined train routes, push routes, and others.)  
\end{table}
Table 1: The interlocking table (partial), provides information about track sections (nodes).  
This RSCN comprises three layers and each layer contains 67 nodes:  
* The LC network includes 140 edges;
* The YX network contains 26 edges;
* The DC network consists of 72 edges.