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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Sang-Moon Lee, Kwang-Yong Kim
Nuclear Technology | Volume 175 | Number 2 | August 2011 | Pages 361-370
Technical Paper | Fission Reactors | doi.org/10.13182/NT11-A12309
Articles are hosted by Taylor and Francis Online.
The shape optimization of the upper plenum of a pebble bed modular reactor (PBMR)-type gas-cooled nuclear reactor has been performed by using three-dimensional Reynolds-averaged Navier-Stokes (RANS) analysis and a multiobjective optimization procedure. A multiobjective genetic algorithm is used for multiobjective optimization. Two objective functions related to the uniformity of the flow distribution at the core inlet and pressure drop through the upper plenum are employed. Three geometric design variables, namely, the ratio of the thickness of the slot to the diameter of the rising channels, the ratio of the height of the upper plenum to the diameter of the rising channels, and the ratio of the height of the slot at the inlet to that at the outlet, are used for the optimization. Latin hypercube sampling is used to determine the experimental points. The response surface approximation model is used to approximate the Pareto-optimal front with three-dimensional RANS analysis using the shear stress transport turbulence model. Seven optimal shapes have been obtained using k-means clustering. From an analysis of two typical optimal designs, it is found that both of the objective functions have been improved remarkably in comparison with the reference design.