differentiation of areas of the Earth’s surface as shown in the character, arrangement, and interrelations over the world of such elements as climate, elevation, soil, vegetation, population, land use, industries, or states, as well as the unit areas formed by the complex of these individual elements (Clarivate Analytics, 2017).
6 Empirical Analysis
6.1 IDR topics identification
(1) IDR topics identification in 2007
Figure 3a is an IDR topics concept lattice between LIS and Medical Informatics in 2007. It covers three topics, including qualitative analysis
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