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Division Spotlight
Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Latest News
Penn State and Westinghouse make eVinci microreactor plan official
Penn State and Westinghouse Electric Company are working together to site a new research reactor on Penn State’s University Park, Pa., campus: Westinghouse’s eVinci, a HALEU TRISO-fueled sodium heat-pipe reactor. Penn State has announced that it submitted a letter of intent to host and operate an eVinci reactor to the Nuclear Regulatory Commission on February 28 and plans to engage with the NRC on specific siting decisions. Penn State already boasts the Breazeale reactor, which began operating in 1955 as the first licensed research reactor at a university in the United States. At 70, the Breazeale reactor is still in operation.
Wolfgang Rothenstein
Nuclear Science and Engineering | Volume 7 | Number 2 | February 1960 | Pages 162-171
Technical Paper | doi.org/10.13182/NSE60-A29086
Articles are hosted by Taylor and Francis Online.
A formula for the escape probabilities of neutrons from the fuel lumps to the moderator and vice versa in a lattice is derived and the validity of simple approximations discussed. These formulas are applied to solve the coupled integral equations for the collision densities in a lattice. First-order corrections to the resonance integral are obtained both for the Narrow Resonance and the Narrow Resonance Infinite Absorber approximations. Numerical results are given for water lattices containing hexagonal arrays of U238 rods, of 0.25 and 0.60 in. diameter, at different water-to-metal volume ratios.
