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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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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
B. A. Worley
Nuclear Science and Engineering | Volume 91 | Number 3 | November 1985 | Pages 293-304
Technical Paper | doi.org/10.13182/NSE85-A17306
Articles are hosted by Taylor and Francis Online.
A standard assumption used in unit-cell interface-current codes is that neutrons enter each spatial region with an isotropic angular distribution. The physical interpretation of this assumption is discussed, and the magnitude of the error introduced by it is shown for a range of practical unit-cell geometries. An improvement on the calculation of first-flight transmission probabilities for one-dimensional unit cells based on limiting the neutron source angular distribution to physically possible neutron flight directions is then presented. For three-region problems, one additional calculation of a revised outer region transmission probability is sufficient for determining all the revised transmission probabilities of interest. Calculation of the revised transmission probabilities requires only minor coding changes and eliminates the improper angular redistribution of neutrons at the region boundaries.