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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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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Proving DRACO will deliver
The United States is now closer than it has been in over five decades to launching the first nuclear thermal rocket into space, thanks to DRACO—the Demonstration Rocket for Agile Cislunar Orbit.
Üner Çolak, Volkan Seker
Nuclear Science and Engineering | Volume 149 | Number 2 | February 2005 | Pages 131-137
Technical Paper | doi.org/10.13182/NSE04-17
Articles are hosted by Taylor and Francis Online.
In this study, the criticality analysis for a pebble bed reactor, HTR-10, is performed with Monte Carlo simulations. The MCNP4B code package is utilized in the analysis with ENDF/B-VI continuous energy cross sections. The full core with the initial loading case is considered in simulations. The variation of the effective multiplication factor as a function of core loading height is also analyzed. Three different geometrical models are employed to see the effect of geometrical detail on the criticality calculations. Results are compared with diffusion calculations as well as the experimental data. Results show that the use of the homogenized fuel zone model does not yield acceptable results and underestimates the core criticality. However, the results obtained by using models with uniform and randomly distributed coated fuel particles in the fuel zone are in quite good agreement and there is not any systematic difference. Furthermore, criticality values do not change significantly with different random arrangements of coated fuel particles in fuel spheres. However, the random and irregular arrangements of pebbles may result in statistically different criticality values at least due to varying streaming effect.