## 7 Conclusions  
This study develops a graph database and matrix-based intelligent generation framework for the assembly sequence of prefabricated components. This framework achieves three objectives: (1) The information interaction center based on the graph database is proposed to address the challenges of automated information query, summary, and retrieval. This center serves as a platform to receive the optimized assembly sequence and corresponding construction schedule. Utilizing the graph database enhances the adequacy of information utilization and provides convenient interactivity. (2) The assembly problem modeling method based on the adjacency matrix and interference matrix is established to describe the connection relationships between components. Moreover, weight, occupied  
Figure 16: Visualization of assembly sequence.  
Figure 15: Two examples and comparisons of treatment to local connection relations.  
space, and interference relationship are identified as critical success factors determining the assembly sequence of prefabricated wall components. Through this modeling approach, the framework provides a comprehensive understanding of the assembly process, enabling efficient decision-making in generating assembly sequences. (3) The double-elite strategy genetic algorithm improves the performance of the traditional genetic algorithm, making the optimization algorithm more adaptive to deal with the assembly sequence problem. In addition, the case study conducted demonstrates the effectiveness of this framework in intelligently generating assembly sequences and reducing the difficulty of assembly during prefabricated building construction.  
In general, the contributions of this framework to the development of construction schedule optimization are threefold. Firstly, this framework verifies the feasibility of transferring the data center from the BIM to the graph database, making information utilization more adequate and interactivity more convenient. Secondly, it offers a powerful tool for inexperienced practitioners to accomplish the assembly task efficiently, smoothly, and safely by providing an intelligently optimized assembly sequence. Furthermore, this research provides a valuable basis for future research on the optimization of autonomous tower crane operations. By integrating the optimized assembly sequence and construction schedule, the framework establishes a solid foundation for the development of intelligent crane control systems, which could potentially increase safety, lower operational costs, and reduce the overall construction time.  
Based on the results of this paper, further work may include the following. (1) In this paper, the influence of the sequence of component production and arrival is simplified and idealized. Future work could investigate how to put a component supply chain into consideration to make the construction schedule more practicable and feasible. (2) Although currently all the research has unanimously chosen the genetic algorithm as the optimization algorithm, there is potential to explore the use of machine learning algorithms for assembly sequence optimization and compare the results with traditional optimization algorithms. (3) The framework developed in this study could be expanded to include the scope of modular building construction, which depends primarily on the assembly task.  
Conceptualization, B.Y.; Methodology, S.J. and M.D.; Software, S.J.; Project administration, D.Z.; Writing--original draft, S.J.; Writing--review & editing, S.J., M.D., D.Z. and Y.H.; Supervision, B.Y. and D.Z. All authors have read and agreed to the published version of the manuscript.  
The study has been supported by the Shanghai 2022 Science and Technology Innovation Action Plan Social Development Science and Technology Research Project (Grant No. 22 dz1201700) and the Top Discipline Plan of Shanghai Universities-Class I.  
Not applicable.  
The data presented in this study are available on request from the corresponding author.  
The authors declare no conflict of interest.