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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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WIPP’s SSCVS: A breath of fresh air
This spring, the Department of Energy’s Office of Environmental Management announced that it had achieved a major milestone by completing commissioning of the Safety Significant Confinement Ventilation System (SSCVS) facility—a new, state-of-the-art, large-scale ventilation system at the Waste Isolation Pilot Plant, the DOE’s geologic repository for defense-related transuranic (TRU) waste in New Mexico.
Alan M. Winslow
Nuclear Science and Engineering | Volume 32 | Number 1 | April 1968 | Pages 101-110
Technical Paper | doi.org/10.13182/NSE68-A18829
Articles are hosted by Taylor and Francis Online.
A formulation of asymptotic neutron diffusion theory for numerical calculations is presented which provides in simple ways for physical features not included in the elementary form of the theory. These are: 1) exponential time dependence, which is provided for by a transformation to steady state; 2) effect of surface curvature on the linear extrapolation length, provided for by means of the principal radii of curvature; 3) material discontinuities, provided for by limiting the current at an interface to its free surface value; and 4) prescribed sources and velocity dependence, provided for by a generalization of the number of secondary neutrons per collision. Numerical results are presented showing that the form of time-dependent multigroup neutron diffusion theory thus obtained is more accurate than the ordinary multigroup formulation especially for small or inhomogeneous systems.
