**3. Methodology**

#### *3.1. Research Framework*

As shown in Figure 1, a research framework involving five steps was developed to explore organization synchronization in terms of complex networks. First, a literature review was conducted to identify 27 construction delay factors (Table 1) and four kinds of organization interaction ways (Table 2). Then, an expert interview was conducted to discuss the reasonableness of the 27 CDFs, determine the types of organizations, and determine the possible organization interactions in complex projects. Second, a questionnaire survey was used to assess the influence of the 27 CDFs on the project schedule and evaluate four kinds of relationships among different units (inter-organization (IO), organizations and CDFs (OCDFs), organizations and interaction ways (OIWs) before the delay, and organizations and interaction ways after the delay). Third, the software NetMiner 4.0 was utilized to visualize the four corresponding complex networks (the IO network, the OCDF network, the OIW network before the delay, and the OIW network after the delay). Subsequently, several parameters were analyzed to compare the network synchronizability, find the key CDFs, and determine the signal organizations in the early stage of local synchronization.

During the above processes, statistical analysis (Step 2) and network analysis (Step 4) were used to refine the key CDFs.

**Figure 1.** Research framework for studying organization synchronization.

Finally, to validate the effectiveness of the CNS theory's application, a typical complex project in Hangzhou, China was adopted as a case project and studied by implementing the above steps. The complex metro project in the case study was assumed to be a project under construction and we also assumed that no delay had occurred. Thus, the key CDFs and the signal organizations could be generated from the theoretical research. If the theoretical results are highly commensurate with the actual reasons for the delay and the responsible organizations, then the feasibility of the CNS theory's application can be proved.

Therefore, by applying the research framework, researchers can predict key causes of delays and the responsible parties in complex projects where project delays have not happened, determine the network synchronizability of the IO network, the OCDF network, and the OIW network before the delay, and adjust organization interactions to achieve better synchronizability in response to project delays.
