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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.
Yasuyoshi Kato
Nuclear Science and Engineering | Volume 104 | Number 4 | April 1990 | Pages 402-411
Technical Note | doi.org/10.13182/NSE90-A23738
Articles are hosted by Taylor and Francis Online.
Spatial mesh effects are studied for three-dimensional x-y-z neutron diffusion calculations. By applying the perturbation theory, it is analytically predicted that the errors in eigenvalue and control rod worth due to the mesh effect vary with the square of the mesh spacing, or inversely with the square of the mesh number, along the x, y, and z axes. The relationships are confirmed numerically by three-dimensional diffusion calculations in ZPPR-10A. Exact solutions are obtained from extrapolation to infinitely fine mesh spacing using these relations and results of coarse-mesh calculations.