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Division Spotlight
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.
Meeting 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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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.
Morton R. Fleishman, Harry Soodak
Nuclear Science and Engineering | Volume 7 | Number 3 | March 1960 | Pages 217-227
Technical Paper | doi.org/10.13182/NSE60-A25705
Articles are hosted by Taylor and Francis Online.
The Spinrad three-group theory of the fast effect is formulated. Recipes are presented for determining the necessary cross sections directly from fundamental data and three-group cross sections for various materials are tabulated. A comparison is made between the three-group theory and one-group theory with respect to the calculation of R, the ratio of fast-to-thermal fissions, and it is found that the three-group theory appears to give better agreement with experiments. The three-group values of Є — 1 are about 20% higher than those calculated from the one-group formula.
