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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.
M. F. Villani, G. P. Couchell, M. H. Haghighi, D. J. Pullen, W. A. Schier
Nuclear Science and Engineering | Volume 111 | Number 4 | August 1992 | Pages 422-432
Technical Paper | doi.org/10.13182/NSE92-A15489
Articles are hosted by Taylor and Francis Online.
A constrained least-squares method is developed for deducing six-group delayed neutron energy spectra from composite spectra measured at six or more delay time intervals following fission. The constraining condition is chosen to yield stable solutions that also provide good fits to the measured spectra. The method is applied to previously measured composite spectra of 235U to obtain six-group delayed neutron energy spectra. The solutions are unique for a large range of constraint spectra. The dependence of the solutions on the choice of six-group parameters (ßj,λj) is also examined.
