## 4 Results  
The industrial network set in this study was based on the I/O table provided by the Bank of Korea. The Bank of Korea, as the central bank of Korea, releases the I/O table approximately every five years to allow for the quantitative analysis of inter-industry relationships. We constructed the data based on the 2020 I/O table, which included industry classifications in 77 medium categories and 170 small categories (see Appendix A). In this study, we used the small aggregated product categories (170 sectors) from the input-output tables provided by the Bank of Korea to ensure a detailed and fine-grained analysis of inter-industry relationships. The final raw data were developed based on the total inter-industry transaction volumes, as shown in Table 2.  
They were set as a weighted graph as they was based on inter-industry transactions. The clustering coefficient was 0.90, which is high and indicates a strong level of connectivity between a specific industry and its neighboring industries. In other words, Korea's industrial structure network can be considered a small-world network, characterized by a high level of interdependence among industries [38]. Examples of small-world networks include academic and informational, economic, biological, technological, and social networks. Figure 2 shows the result of network visualization with a subgraph generated by setting the following as specific nodes, which can be considered part of the transportation and logistics industry: land transport services, water transport services, air transport services, warehousing and transport support services, and postal and courier services. It can be considered that the small-world network maintains high clustering both within the overall network and its subcomponents, following a complex hierarchical structure. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Cluster** & **Definition** & **Example Industries** \\ \hline Primary Industry (1-node cluster) & Industries directly interacting with the transportation and logistics industry & Logistics, Distribution, Transportation \\ \hline Secondary Industry (2-node cluster) & \
\begin{tabular}{c} Industries providing intermediate goods \\ or connected to sublevels of the transportation and logistics industry \\ \end{tabular} & Manufacturing, Steel, Energy \\ \hline Tertiary Industry (3-node cluster) &
\begin{tabular}{c} Industries indirectly related but playing \\ an important role in the overall network \\ path \\ \end{tabular} & IT Services, Finance, Administrative Support \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Cluster Definitions in the Transportation Logistics Industry Ecosystem. Figure 2: Visualization of Korea’s industrial network. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Input Sector** & **Output Sector** & **Total Transaction Volume** \\
**(Rows)** & **(Columns)** & **(Million Won)** \\ \hline Growing of crops & Growing of crops & 1,036,392 \\ \hline Animal production & Growing of crops & 63,642 \\ \hline Gathering of non-wood forest products & Growing of crops & 41,856 \\ \hline Seafood & Growing of crops & 331 \\ \hline Agriculture, Forestry, and Fisheries & Growing of crops & 522,747 \\ \hline Mining of coal, crude petroleum, and natural gas & Growing of crops & 0 \\ \hline Mining of metal ores, mining of non-metallic minerals, except fuel & Growing of crops & 929 \\ \hline Food products & Growing of crops & 20,244 \\ \hline Beverages & Growing of crops & 2975 \\ \hline Manufacture of tobacco products & Growing of crops & 0 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: 2020 I/O table raw data. Table 3 shows the weighted degree centralities of each industry for the relevant network in descending order. Industries focused on distribution, manufacturing, construction, and resources, such as wholesale and retail services, metal processing, building construction, and coal and petroleum products, showed high values of weighted degree centrality.