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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.
Takeo Nishigori
Nuclear Science and Engineering | Volume 108 | Number 4 | August 1991 | Pages 347-354
Technical Paper | doi.org/10.13182/NSE91-A23834
Articles are hosted by Taylor and Francis Online.
The effect of a reactivity insertion in a point reactor is formulated as a linear feedback process, and a simple exponential mode representation is proposed as an analytical solution that is valid at small times. The solution contains a fast transient mode as well as slow ones, and it resolves the stiffness problem in a very simple way. With a ramp reactivity insertion as an example, it is shown that this analytical solution is valid for a time interval that is much longer than the time-step size used in the conventional numerical integration, and it is thus useful in reducing computing time.
