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Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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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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NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
G. P. Calame, F. D. Federighi, P. A. Ombrellaro
Nuclear Science and Engineering | Volume 10 | Number 1 | May 1961 | Pages 31-39
Technical Paper | doi.org/10.13182/NSE61-A25926
Articles are hosted by Taylor and Francis Online.
A variational procedure for calculating thermal cross sections and diffusion theory parameters is described. The method permits the calculation of an approximate lethargy-dependent Wigner Wilkins flux spectrum for a region as a linear combination of two lethargy- and temperature-dependent base spectra. The coefficients for linearly combining the base spectra are provided by the theory and once the coefficients are calculated the flux is determined. The average microscopic cross sections and diffusion theory parameters for the region are calculated from a flux weighted average of lethargy-dependent microscopic cross sections and diffusion constants. Cross sections and diffusion theory parameters calculated in this manner agree well with those obtained from the SOFOCATE code.
