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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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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.
G. S. Brunson, E. N. Pettitt, and R. D. McCurdy
Nuclear Science and Engineering | Volume 1 | Number 2 | May 1956 | Pages 174-184
Technical Paper | doi.org/10.13182/NSE56-A17521
Articles are hosted by Taylor and Francis Online.
Delayed neutron studies have been made in the Experimental Breeder Reactor (EBR), using a conventional sample transfer system and a neutron counter comprised of BF3 tubes in a graphite geometry. Samples of Th, U233, U235, U238, and Pu were irradiated in a fast flux; samples of U233, U235, and Pu in a thermal flux. The ratio of the delayed neutron yield per fission (based on the longest four periods) to the delayed neutron yield per fast fission of U235 was determined as: for fast fission of U233, 0.414 ± 7.5%; for fast fission of Pu, 0.405± 7.5%; for fast fission of Th, 3.09 ± 17%; for fast fission of U238, 2.23 ± 7.5%. The ratio of fast fission to thermal fission delayed neutron yields was not significantly different from unity for all samples except Pu, where the ratio of thermal to fast fission yields was 0.888 ± 6%. This latter is believed to be primarily attributable to the 5% fraction of Pu240 in the sample.
