# A Formation Mechanism of Spatial Distribution Pattern of Industrial Clusters under Flow Space
## 3 Materials and Methods
### Results of the Causal Mechanism of Industrial Aggregation
Table 4 summarizes the typical characteristics of the industrial agglomeration development of cities in the Yangtze River Delta region and provides suggestions for such development on a city scale. * Shanghai's industrial agglomeration intensity is relatively sensitive to the level of human resources, economic development, and technological innovation, indicating that the regulation of Shanghai's industrial agglomeration intensity can be directly regulated from several angles, and because of the interconnection and influence of urban elements, the effect of the regulation influence will be continuously expanded to all kinds of urban geographical elements. In addition, as the 'leading city' in the Yangtze River Delta region, Shanghai's industrial agglomeration intensity and its sensitivity to the influencing factors indicate that the city also has great development potential, industrial development vitality, great absorption, and integration of the three main influencing factors, etc. Shanghai's absorption power is strong because the large-scale agglomeration industries can provide a lot of employment opportunities. Meanwhile, due to its relatively high cost of consumption and relatively low cost of livability, Shanghai's overall human resource mobility is relatively high. Therefore, given today's shortage of talent resources, retaining highly skilled personnel and basic labor force is an issue that the Shanghai government and related departments need to focus on;
* The intensity of industrial agglomeration in Hangzhou is relatively insensitive to the level of economic development and human resources, and relatively sensitive to the level of technological innovation. Such cities have sufficient market labor and economic base investment. However, their industrial technology is relatively backward and the demand for technology is strong. In terms of the technology innovation flow trend network, Hangzhou has a relatively high level of technology innovation compared with the surrounding cities, but its technology innovation development level hinders the city's industrial agglomeration. Therefore, it needs to invest heavily in technology innovation and attract high-quality talents in order to develop the agglomeration industry. * Nanjing and Hangzhou are similar, but Nanjing shows more obvious sensitivity to the influencing factors. Therefore, Nanjing has a more significant effect when regulating the influencing factors of industrial agglomeration intensity; \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Economic** & **Technology** & & \\
**Development** & **Innovation** & & \\ \hline S & S & S & Shanghai, Suzhou \\ S & S & INS & Xuzhou \\ S & INS & INS & — \\ S & INS & S & Jinhua, Wuxi, Hefei, \\ INS & S & S & Huangshan \\ INS & INS & S & Nantong City, \\ INS & INS & INS & Taizhou \\ INS & S & INS & Nanjing, Hangzhou, \\  & & & Zhenjiang \\ \hline \hline \end{tabular} S = sensitive, INS = insensitive.  
\end{table} 
Table 4: Sensitivity of factors influencing the development of urban industrial agglomeration. * Hefei is not sensitive to the level of technological innovation and is relatively sensitive to the level of economic development and human resources, indicating that in the western region of the Yangtze River Delta, the development of industrial technological innovation is not a major concern, or that the current level of urban technology is sufficient to support the needs of intra-city industrial development. The biggest obstacle to the development of intra-city industrial agglomeration is the severe shortage of labor, so the level of human resources is an important factor in determining industrial agglomeration. Thus, it is inferred that labor-intensive industries are mainly distributed in the western part of the Yangtze River Delta;
* Nantong, Taizhou, and Huangshan are relatively sensitive to the level of human resources, indicating a shortage of labor force, and that vigorously introducing labor force is a key measure to promote industrial agglomeration.