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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
Masao Yamanaka, Cheol Ho Pyeon, Takahiro Yagi, Tsuyoshi Misawa
Nuclear Science and Engineering | Volume 183 | Number 1 | May 2016 | Pages 96-106
Technical Paper | doi.org/10.13182/NSE15-51
Articles are hosted by Taylor and Francis Online.
Experiments on the thorium-loaded accelerator-driven system (ADS) were carried out at the Kyoto University Critical Assembly to reevaluate the accuracy of reactor physics parameters, including prompt neutron decay constants reaction rate distributions, subcriticality, and subcritical multiplication factor, and to reveal the dependency of these parameters on the external neutron source by varying the external neutron source of 14-MeV neutrons and spallation neutrons generated by 100-MeV protons. In preparation for thorium-loaded ADS experiments, renewed irradiation experiments are conducted with small and thin foils of thorium in the critical state to reevaluate the accuracy of the experimental analyses. In the ADS experiments, reactor physics parameters are found to be different in the same core when the external neutron source is injected separately with 14-MeV neutrons and spallation neutrons. By comparing with the calculated results, the significant impact of external neutron sources on the neutron characteristics of ADS is obtained in both the static and the kinetic experimental analyses.
