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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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.
H.Nakamura
Nuclear Science and Engineering | Volume 118 | Number 4 | December 1994 | Pages 235-248
Technical Paper | doi.org/10.13182/NSE94-A21494
Articles are hosted by Taylor and Francis Online.
A semiempirical formula for neutron detector responses, to be used to infer reactivities in subcriticality measurements, is presented. A formal theory for the multipoint approximation of the Boltzmann operators makes possible the description of a large variety of nuclear fuel systems by means of an equivalent two-point model that regards a whole system as the coupled system made up of an arbitrary number of nuclear fuels. Because the analytic formula includes the fitting parameter associated with the detector configuration and because the removal of spatial effects or higher mode contaminations in the detector responses is accomplished by devising the detector configurations, the conventional point approximation can be used to infer the reactivity of a far-subcritical system. For an example of an application to existing experiments, the current method is used to analyze subcriticality measurements by using the 252Cf source-driven neutron noise analysis method.
