## 5 Conclusions  
The present study determined the influential articles, authors, and journals related to the main research topics and the development directions of the field of RFID. Moreover, a citation analysis and a key-route main path analysis of critical papers were conducted to identify the core research in studies of RFID. The growth trajectory of academic papers was described to provide a deeper understanding of the development trends of research into RFID. The present study combined main path, clustering, and text mining analyses to explore the overall development trajectory of the RFID-related literature. The main path analysis revealed that RFID applications have mainly focused on manufacturing. Key-route main path analyses of the critical paths were performed to analyze the research topics emphasized in the clusters. The overall development track and the connections between clusters \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Cluster** & **Research Theme** & **Published Year** & **Number of Papers** & **Is the Maturity Period? (Yes/No)** \\ \hline
7 & Construction material management & 1995–2019 & 145 & No, it is the growth period in 2019. \\
8 & Beehive model experimentation & 2002–2019 & 66 & No, it is mature in 2017. \\
9 & Erratic tracking experimentation & 2006–2019 & 23 & Yes, it is mature in 2019. \\
10 & Aquaculture & 2011–2019 & 18 & No, it is the growth period in 2019. \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Research themes ranked seventh to tenth. Figure 8: Growth curve of the numbers of papers. were explored through six topics, namely in supply chain management, antenna design, collision prevention protocols, privacy and safety, tag sensors, and localization systems. In the literature review, more than papers on RFID applications in nonmanufacturing industries were collected, and four other clusters of research themes were discovered the technology has been successfully applied in construction and aquaculture. The following five conclusions were drawn:  
1. RFID applications in supply chain management: Such applications enhance the operating time, reduce management costs and perceived risk, and eliminate idle time. Thus, in these RFID applications, multiple targets can be simultaneously and rapidly identified, and information storage advantages more favorable than those offered barcodes are provided. 2. RFID applications in antenna design: The aforementioned authors suggested that researchers should focus on RFID localization algorithms, which have continually been developed. Overall, various RFID-based solutions have been proposed for improving the properties of antennas. 3. RFID applications in collision prevention protocols: RFID technology has been applied to collision prevention because signal collision reduces the signal's communication capacity, lowers system performance, and consumes considerable power. 4. RFID applications in localization systems: By using the locations of adjacent tags, the corresponding algorithm can try and error estimation, thereby leading to higher estimation accuracy. 5. RFID applications in tag sensors: RFID tag sensor technology has self-tuning functionality and can thus adjust to environmental changes. In addition, relatively special applications were found in the clusters--applications in construction material management, applications in beehive model experiments, aquaculture, and erratic tracking experimentation. As a result of the radio frequency identification applications combine with the emerging technology, in construction material management and aquaculture are currently growing topics. The following are four conclusions:  
1. RFID applications in construction material management: By implementing RFID technology, a construction company can overcome many of the issues and frustrations of managing and tracking materials. In the past five years, scholars have gained a clear understanding that Internet of Things (IoT) and emerging technologies have begun to be applied to material management systems in the literature.