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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.
Donald S. Rampolla
Nuclear Science and Engineering | Volume 31 | Number 3 | March 1968 | Pages 396-414
Technical Paper | doi.org/10.13182/NSE68-A17584
Articles are hosted by Taylor and Francis Online.
In the design of nuclear reactors it is frequently necessary to adjust the parameters appearing in the equations describing neutron transport, e.g., the macroscopic absorption cross section in the diffusion equation, in order to force region reaction rates to agree with results of more exact calculations or experiment. Given a multiregion cell problem with a specified absorption rate in each region it is proved that there exists, for any neutron transport equation that has a solution that is everywhere positive, a non-unique set of region absorption cross sections which yield the specified absorption rates; however, if the cross section is fixed in one region, the set is, in a specially defined sense, unique. Two systematic iterative methods for obtaining such sets of region cross sections are presented; one of these methods has been incorporated into a computer program.
