Figure 1.
The image shows four maps of China from 2011, 2015, 2018 and 2021, each depicting regional research activity levels. A legend classifies areas as non-research or into ranges from 0.1062 to 0.7612, with shading variations representing increasing research intensity. Each map includes an inset showing smaller islands labelled Nanhai Zhidiao and a north arrow for orientation. The maps are arranged in a grid format, allowing direct visual comparison of changes in research activity distribution over the years.The evolution of the level of foreign R&D activity in China
Source: Authors’ own work