The seismological expert credited with ensuring that Japan would embark a careful and methodical return to atomic power by demanding rigorous adherence to safety checks has left the decision-making panel of the Nuclear Regulation Authority after completing his two-year stint.

Kunihiko Shimazaki, the sole seismologist on the five-person panel, is to be replaced by a strong advocate of nuclear power.

A second commissioner whose term also expired Thursday is Kenzo Oshima, a former ambassador to the United Nations. He will be replaced geologist and Tohoku University professor Akira Ishiwatari.