# A Study on Finding Partners through Patent Network Analysis of UAM (Urban Air Mobility)
## 3 Analysis
### Network Analysis  
#### 3.4.1 Network Analysis by Company  
Network analysis was conducted using the Fuchterman-Reingold algorithm of the Gephi network analysis tool. Through the network visualization shown in Figures 7-9, the degree of cooperative development for each company can be identified briefly. It can  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Category** & **BOEING** & **AIRBUS** & **BELL** \\ \hline
2014 & 7.4 & 76.3 & 2.0 \\
2015 & 1.5 & 72.2 & 2.0 \\
2016 & 11.8 & 69.7 & 4.1 \\
2017 & 26.5 & 53.3 & 2.0 \\
2018 & 33.9 & 68.1 & 0.0 \\ \hline \hline \end{tabular}
\end{table}
Table 10: Technology strength.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Category** & **BOEING** & **AIRBUS** & **BELL** \\ \hline A (propulsion system) & 1.0 & 3.7 & 1.0 \\ B (a aerodynamic design) & 0.7 & 1.2 & 1.2 \\ C (material/structure) & 1.2 & 1.5 & 1.1 \\ D (battery) & 0.8 & 1.2 & 1.1 \\ E (control/safety) & 0.6 & 1.0 & 1.0 \\ F (navigation/communication) & 0.8 & 0.8 & 0.0 \\ G (cybersecurity) & 0.5 & 0.8 & 0.0 \\ \hline \hline \end{tabular}
\end{table}
Table 11: Patent family size.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Category** & **BOEING** & **AIRBUS** & **BELL** \\ \hline A (propulsion system) & 0.8 & 0.7 & 1.5 \\ B (a aerodynamic design) & 1.4 & 0.7 & 0.9 \\ C (material/structure) & 1.1 & 0.9 & 0.0 \\ D (battery) & 1.9 & 0.7 & 0.4 \\ E (control/safety) & 1.1 & 1.2 & 0.8 \\ F (navigation/communication) & 1.3 & 0.7 & 0.0 \\ G (cybersecurity) & 1.7 & 0.6 & 0.7 \\ \hline \hline \end{tabular}
\end{table}
Table 9: Patent impact index.  
be seen immediately that AIRBUS develops through open innovation, while BELL takes a closed-innovation strategy. AIRBUS filed 1148 UAM patent applications with 212 co-applicants. In the group of company-oriented patent applications (AIRBUS OPERATIONS GMBH, AIRBUS SAS), it was identified that the elementary technology for all UAM fields was being developed.  
BOEING filed 444 UAM patent applications with 87 co-applicants. It was identified that the intensity of the joint application with the California Institute of Technology and PH MADISON FUNDING LLC was high. Joint application with universities has the advantage of being able to conduct continuous research in connection with recruitment, but it is judged that filing for patents with NPEs (patent monsters) such as PH MADISON FUNDING LLC is not a strategy with the possibility of future patent litigation in mind.  
BELL filed 39 UAM patent applications with 13 co-applicants. Co-applicants are concentrated in category A (propulsion system), and the cooperation index with TEXTRON appeared to be high.  
As a result of the degree centrality analysis, the value of a relatively large network is high because the connection centrality is affected by the size of the network. The result of the degree centrality analysis is shown in Table 12. Degree centrality was found to be ordered as AIRBUS, BOEING, BELL, highest to lowest, but because of normalization, it appeared as BOEING, BELL, AIRBUS. The closeness centrality analysis confirmed that AIRBUS's degree of cooperative relationship was higher than that of other companies. As a result of the betweenness centrality analysis, it was confirmed that the co-applicant of AIRBUS plays a good role as a research intermediary.