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Conference Spotlight
2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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Nuclear Science and Engineering
April 2026
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February 2026
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Swiss nuclear power and the case for long-term operation
Designed for 40 years but built to last far longer, Switzerland’s nuclear power plants have all entered long-term operation. Yet age alone says little about safety or performance. Through continuous upgrades, strict regulatory oversight, and extensive aging management, the country’s reactors are being prepared for decades of continued operation, in line with international practice.
Nuclear Criticality Safety Division 2025 Conference
Japan Atomic Energy Agency (JAEA)
Group Leader in the Criticality Safety Research Group of the Nuclear Safety Research Center
Dr. Satoshi Gunji completed his PhD in Engineering at Tohoku University before joining the Power and Industrial Systems Research and Development Center of Toshiba Corporation in 2007 as a researcher in the Nuclear Reactor System Analysis Group. Before the accident at the Tokyo Electric Power Company's Fukushima Daiichi Nuclear Power Plant, his main work was on criticality safety of next-generation light water reactor fuel. He was also an experimenter and an operator of the Toshiba Nuclear Critical Assembly.
After Toshiba decided to decommission the NCA, he moved to the Criticality Safety Research Group at the Japan Atomic Energy Agency (JAEA), where he currently works. At the time, JAEA was proceeding with plans to modify the criticality assembly STACY to conduct criticality assessments of the fuel debris generated by the FDNPP accident. He participated in this project as a criticality safety expert and planned the criticality experiment plans. STACY achieved first criticality in 2024, and he has been directing subsequent experiments.
Last modified August 26, 2025, 10:54am CDT
