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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.
G. Th. Analytis, J. K.-H. Karlsson {ti}Spatial Neutronic Decoupling of Large Fast Breeder Reactor Cores: Application to Nuclear Core Design Method
Nuclear Science and Engineering | Volume 131 | Number 2 | February 1999 | Pages 286-292
Technical Note | doi.org/10.13182/NSE99-A2036
Articles are hosted by Taylor and Francis Online.
It is well known that after one of the spatial harmonics of a boiling water reactor (BWR) is driven toward limit-cycle oscillations with a decay ratio very close to 1, the nonlinear behavior of the system starts to manifest itself, and a series of resonances appears at frequencies that are multiples of the characteristic oscillation frequency (commonly called harmonic frequencies). Several such resonances have been clearly identified during measurements in BWRs during which the system is in the unstable, limit-cycle oscillations regime. The ability to identify three and possibly four of these harmonic resonance peaks in the neutron spectra of Ringhals-1 is reported. For the measurements to be analyzed, these resonances are due to the limit-cycle oscillations not of the fundamental but of the first spatial harmonic of the neutron flux.