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Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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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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Latest News
NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
Jaeha Kim, Yonghee Kim
Nuclear Science and Engineering | Volume 194 | Number 1 | January 2020 | Pages 1-13
Technical Paper | doi.org/10.1080/00295639.2019.1642016
Articles are hosted by Taylor and Francis Online.
This paper presents the methodology and performance of the Hybrid Coarse-Mesh Finite Difference (HCMFD) algorithm for transient pinwise analyses of three-dimensional (3-D) pressurized water reactor (PWR) problems. The time-dependent neutron diffusion equations and their applications in two steps of the HCMFD algorithm, i.e., local and global iterations, are introduced in detail. Taking into account the characteristics of the local-global nonlinear HCMFD iterations, an optimization strategy to minimize the computing time of the transient HCMFD calculation is established by focusing on the balance between the number of local and global calculations. Based on the optimization strategy, the actual computational performance of the transient HCMFD algorithm, in view of both computing time and accuracy, is evaluated for the core of a big-sized conventional PWR in this work. To demonstrate the effectiveness of the optimized iteration strategy, various slow and fast transients including a rod ejection transient are simulated by the transient HCMFD algorithm. It is clearly shown that a 3-D pin-resolved whole-core transient solution for a big PWR can be obtained in a reasonably short computing time by the transient 3-D HCMFD algorithm.
