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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.
Farzad Rahnema, Piero Ravetto
Nuclear Science and Engineering | Volume 128 | Number 2 | February 1998 | Pages 209-223
Technical Paper | doi.org/10.13182/NSE98-A1952
Articles are hosted by Taylor and Francis Online.
It is shown that a perturbation in the external boundary of a system can be converted into (treated as) a perturbation in the boundary condition of the neutron balance equation. As a result, one may then use existing boundary condition perturbation or variational methods to estimate the change in the parameters of interest. The equivalent perturbation in the boundary condition is derived both in transport theory and its diffusion approximation for eigenvalue as well as fixed-source problems. Generalized boundary conditions in both diffusion and transport theory are considered. The existence of a solution to the problem with the equivalent boundary conditions that are nonstandard is investigated through analytic examples. The analysis is limited to first-order perturbation theory.
