Dynamic of Publication Network in German Photovoltaic Industry

Abstract

Besides high policy-induced motivations for development of research activities in photovoltaic industry, there have been a few social network studies concentrating on the scientific publication in this field. This study tried to shed light on the structure and evolution of publication network in German PV industry from 1988 to 2013. For this purpose, using the centrality indices, We realized the most influential actors as potential source of knowledge and actors who play the central role in knowledge production and diffusion. In next step, we investigated the dynamic of co-authorship network of scientists. Results showed that against the downward trend of network’s cohesion, overall compared to the same size random generated network, German PV co-authorship network is characterized as a small world network which emphasizes the efficient diffusion of knowledge compare to other type of network. Finally, to disclose the drivers behind the evolution of co-authorship network, we hypothesized two different scenarios. First, using descriptive analysis, the existence of preferential attachment mechanism is investigated. Fitting power law distribution over degree of nodes rejected our hypothesis for all investigating time windows. Therefore, preferential attachment mechanism cannot significantly explain the evolution of the network and reveals that network is robust in response to removal of large nodes. Second, looking at the composition of knowledge on map of science provided strong evidence in support of interdisciplinarity nature of German PV industry. Our descriptive analysis shows that along with existence of leading macro-disciplines such as Materials Science and Physics Applied, new subject categories of science have found a significant position over the existing knowledge domain during the observed period