Fig. 16

Keywords co-occurrence analysis. A The co-occurrence network visualization map of the top 104 keywords. The visualization map of publications for 104 keywords forming 3 collaborating clusters (nodes with the same color); a node represents a keyword, the size of the node represents the number of publications, a link shows collaboration, and the distance and the thickness of the link between nodes show the relative strength of the relation. B The co-occurrence overlay visualization map of the top 104 keywords. The color of node represents the average publication year of the keywords, and the blue to yellow represents the average publication year from early to late