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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. G. Kaper
Nuclear Science and Engineering | Volume 28 | Number 3 | June 1967 | Pages 415-425
Technical Paper | doi.org/10.13182/NSE67-A28956
Articles are hosted by Taylor and Francis Online.
An approximate theory for the slowing down of neutrons in a nonmultiplying medium with plane symmetry is described. The theory is based on an approximate form of the transfer function for elastic scattering under the hypothesis that the mass number of the moderator is larger than one. In the A−N approximation the slowing down equation is reduced to a finite system of differential equations with respect to the lethargy variable. A detailed study has been made of the results obtained in the A−N approximation with N = 0 and N = 1. Special attention has been paid to a comparison of the A−1 approximation with age theory and asymptotic theory.
