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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.
Sten-Örjan Lindahl
Nuclear Science and Engineering | Volume 53 | Number 4 | April 1974 | Pages 475-478
Technical Note | doi.org/10.13182/NSE74-A23378
Articles are hosted by Taylor and Francis Online.
Using the multigroup diffusion equation, a reciprocity relation is established for an arbitrarily shaped body. This relation expresses the flux caused by a source inside the body in terms of the flux resulting from an incident current on that body. In the multigroup case for one-dimensional bodies with flat sources and in the one-group case for rectangular two-dimensional bodies with an arbitrary source, practical formulas are derived from this relation. These give the leakage from a body in terms of its reflection and transmission properties. An advantage of the use of this reciprocity relation is the improved computational efficiency in response matrix calculations.
