# Main Trend Topics on Industry 4.0 in the Manufacturing Sector: A Bibliometric Review
## 3 Results
### Source Analysis  
Figure 4(a) displays the ranking of journals based on the quantity of published articles, while Figure 4(b) illustrates the scientific journals with the highest level of discussion and citation within the sample obtained. \begin{table}
\begin{tabular}{l l} \hline \hline
**Description** & **Results** \\ \hline
**Main Information about Data** & \\ \hline Timespan & 2020:2024 \\ Sources (Journals, Books, etc.) & 286 \\ Documents & 1069 \\ Annual Growth Rate \% & 30.77 \\ Document Average Age & 2.15 \\ Average citations per doc & 27.28 \\ References & 94,694 \\ \hline
**Document Contents** & \\ \hline Keywords Plus (ID) & 2247 \\ Author’s Keywords (DE) & 2813 \\ \hline
**Authors** & \\ \hline Total Authors & 3433 \\ Authors of single-authored docs & 45 \\ \hline
**Authors Collaboration** & \\ \hline Single-authored docs & 50 \\ Co-Authors per Doc & 3.81 \\ International co-authorships \% & 36.11 \\ \hline
**Document Types** & \\ \hline Review & 592 \\ review; book chapter & 1 \\ review; early access & 476 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Summarizes an approximation of the characteristics of the sample obtained. Figure 5: Journal Metrics: Quantity and Quality. (**a**) Most Relevant Sources (2020–2024); (**b**) Most Local Cited Sources (2020–2024). Although both indicators are fundamental, there are others that weigh factors such as the number of citations, the quantity of cited articles, and the relationship between them (see Table 2 and Figure 6). For example, the H-index is a widely used metric to assess the impact of a researcher based on their publications and citations [35; 36], which many authors complement with the G-index, a measure that provides a distinctive ranking of authors based on accumulated values of the square root, enabling a unique evaluation of productivity and impact [37; 38]. From this analysis, the top 5 scientific journals in the research domain in question are identified:  
1. Sustainability: This journal has the highest h-index (27) among those analyzed and a high g-index (47), indicating significant influence and a considerable number of \begin{table}
\begin{tabular}{l c c c c c c} \hline \hline
**Element** & **h\_Index** & **g\_Index** & **m\_Index** & **TC** & **NP** & **PY\_Start** \\ \hline SUSTAINAABILITY & 27 & 47 & 5.4 & 2487 & 103 & 2020 \\ JOURNAAL OF MANUFACTURING SYSTEMS & 19 & 35 & 3.8 & 1588 & 35 & 2020 \\ SENSORS & 19 & 35 & 3.8 & 1356 & 58 & 2020 \\ APPLIED SCIENCES-BASEL & 17 & 28 & 3.4 & 889 & 52 & 2020 \\ JOURNAAL OF CLEANER PRODUCTION & 17 & 32 & 3.4 & 1897 & 32 & 2020 \\ COMPUTERS \& INDUSTRIAL ENGINEERING & 16 & 27 & 3.2 & 1320 & 27 & 2020 \\ INTERNATIONAL JOURNAAL OF PRODUCTION RESEARCH & 16 & 25 & 3.2 & 1433 & 25 & 2020 \\ INTERNATIONAL JOURNAAL OF ADVANCED MANUFACTURING & 14 & 27 & 2.8 & 738 & 36 & 2020 \\ TECHNOLOGY & 13 & 16 & 2.6 & 1106 & 16 & 2020 \\ COMPUTERS IN INDUSTRY & 10 & 16 & 2 & 260 & 18 & 2020 \\ ELECTRONICS & & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Sources’ Local Impact. Figure 6: H Index. cited documents. Additionally, it has a high total number of citations (2487) and a significant quantity of published documents (103). * Journal of Manufacturing Systems: With an h-index of 19 and a g-index of 35, this journal also demonstrates strong influence in the field. It presents a considerable number of citations (1588) and a moderate quantity of published documents (35). * Sensors: This journal has h-index and g-index values similar to those of the Journal of Manufacturing Systems (19 and 35 respectively), indicating significant influence in the field. However, it has a slightly higher number of published documents (58). * Journal of Cleaner Production: With an h-index of 17 and a g-index of 32, this journal also exhibits substantial influence. It has a high total number of citations (1897) and a moderate quantity of published documents (32). * Applied Sciences-Basel: Although it has a slightly lower h-index (17), this journal has a similar g-index (28), suggesting considerable influence in the field.