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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.
W. L. Hendry
Nuclear Science and Engineering | Volume 45 | Number 1 | July 1971 | Pages 1-6
Technical Paper | doi.org/10.13182/NSE71-A20339
Articles are hosted by Taylor and Francis Online.
Systems that are below prompt critical are considered, and the linear time-dependent neutron transport equation in a quite general setting is studied. Both source and cross sections are allowed to depend on space, energy, and time. The method of matched asymptotic expansions is used to find an asymptotic solution uniformly valid in time. This solution is written in the form of a sum of solutions to simpler problems and for most practical problems is essentially exact. After a short initial time period, the transport equation (with delayed neutrons neglected) may be solved at a given time by a single inversion of the steady-state transport operator; i.e., with a steady-state code.
