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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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.
Ser Gi Hong, Nam Zin Cho
Nuclear Science and Engineering | Volume 132 | Number 1 | May 1999 | Pages 65-77
Technical Paper | doi.org/10.13182/NSE99-A2049
Articles are hosted by Taylor and Francis Online.
A new transport theory method of characteristic direction probabilities (CDP), which can treat complicated geometries with computational efficiency, is presented. In the method, the entire problem is divided into subsystems or cells that are further subdivided into finer mesh regions (i.e., computational meshes). Within a subsystem or cell, the fine meshes are coupled by the directional transmission and collision probabilities for each characteristic direction. In other words, all fine meshes in a subsystem are not coupled together but only the fine meshes along the characteristic line are coupled for each direction. This is in contrast to the traditional collision probability methods (CPMs). To calculate the directional probabilities, ray tracing with the macroband concept is performed only on each subsystem type. To couple the subsystems, the angular flux (not the current as in the interface current method) on the interface between the adjacent subsystems is used. Therefore, the method combines the most desirable features of the discrete ordinates methods and those of the integral transport methods. To verify CDP, it is applied to two benchmark problems that consist of complex meshes and is compared with other methods (CPM, method of characteristics, and Monte Carlo method). The results show that CDP gives accurate results with short computing time.