Global trends in DEM-related research from 1994 to 2013: a bibliometric analysis
Using the science citation index and the social sciences citation index databases, we performed a bibliometric analysis of the global studies on the digital evaluation model (DEM) that were conducted between 1994 and 2013. We identified the authorial, institutional, international, categorical, spatiotemporal patterns, and hotspots in DEM-related research. The number of DEM-related publications has been continuously increasing since 1994. Geology, engineering, and physical geography were the most frequently used subject categories in DEM-related studies, whereas Geomorphology, International Journal of Remote Sensing, and IEEE Transactions on Geoscience and Remote Sensing were the most active journals in the field. Toutin, T., Favalli, M., and Hancock, G. R. were the most prolific authors in DEM-related research. Authors of DEM-related research were mostly located in the USA, the European Union, and East Asia. The USA, China, and the UK were the top three most productive countries. The Chinese Academy of Sciences, the largest contributor of single-institution and collaborative publications on DEM, has a key position in collaboration networks. Both the number of articles that are internationally and inter-institutionally collaborative is increasing, with the former being more prevalent than the latter. Through keyword analysis, we observed several interesting terminology preferences, revealed the adoption of advanced technologies, and examined the patterns and underlying processes of geoscience. In summary, our study identified the quantitative, qualitative, temporal, and spatial characteristics, academic collaborations, as well as hotspots in scientific outputs and provided an innovative method of revealing global trends in DEM-related research to guide future studies.