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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.
Eugene L. Wachspress
Nuclear Science and Engineering | Volume 3 | Number 2 | February 1958 | Pages 186-200
Technical Paper | doi.org/10.13182/NSE58-A25460
Articles are hosted by Taylor and Francis Online.
A method for determining effective cross sections for geometrically thin absorbing regions in multigroup calculations is described. The effective absorption cross section in multigroup calculations provides a smooth transition from the usual diffusion theory cross section for low absorption slabs to the λtr extrapolated end-point condition for black slabs. In effect, the average flux between mesh points of the difference equation grid is related to the fluxes at the mesh points. Self-shielding effects are accounted for by material cross-section rather than difference equation modification. Application of the theory to lattice calculations is discussed, and comparisons are made with other methods for limiting cases.
