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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.
R. N. Hwang
Nuclear Science and Engineering | Volume 167 | Number 1 | January 2011 | Pages 1-39
Technical Paper | doi.org/10.13182/NSE10-004
Articles are hosted by Taylor and Francis Online.
The fundamental basis regarding treatment of unresolved resonances and the construction of probability tables and the relevant issues with their application to reactor physics is critically examined. A theoretical model using integral transform techniques is developed that provides a viable alternative to the stochastic-based “ladder” method widely used to construct probability tables. A brief review of the statistical theory for treating the unresolved resonances is presented, followed by a critical examination of these methods. Then a reference method for computing various probability distributions at 0 K is derived analytically for Breit-Wigner resonances. This reference model provides the analytical insight and conceptual basis for extension to the general case of arbitrary temperature. The generalization to arbitrary temperature is accomplished using the Chebyshev expansion while maintaining the general forms of the distributions. Results of extensive benchmark calculations to verify the viability of the proposed method are presented. Finally, there is discussion of the remaining challenges in application of this new analytical approach, in particular, the issue of its extension beyond the Breit-Wigner approximation.