The decision-making process that precedes the introduction of a new energy system should strive for a balance among human security, environmental safeguards, energy security, proliferation risk, economic risks, etc. For nuclear energy, the Fukushima Daiichi nuclear disaster (Fukushima disaster) has brought forth a strong need for transvaluation of the present technology. Here, we analyzed bibliographic records of publications in nuclear science and technology to illustrate an overview and trends in nuclear energy technology and related fields by using citation network analysis. We also analyzed funding data and keywords assigned for each project by co-occurrence network analysis. This research integrates citation network analysis and bibliometric keyword analysis to compare the global trends in nuclear energy research and characteristics of research conducted at universities and institutes in Japan. We show that the Chernobyl accident had only a limited influence on basic research. The results of papers are dispersed in diverse areas of nuclear energy technology research, and the results of KAKEN projects in Japan are highly influenced by national energy policy with a focus on nuclear fuel cycle for energy security, although KAKEN allows much freedom in the selection of research projects to academic community. (C) 2013 Elsevier Ltd. All rights reserved.