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Mathematics & Computation
Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Mónica Chillarón Pérez, Vicente E. Vidal, Gumersindo J. Verdú, Gregorio Quintana-Ortí
Nuclear Science and Engineering | Volume 198 | Number 2 | February 2024 | Pages 193-206
Research Article | doi.org/10.1080/00295639.2023.2199677
Articles are hosted by Taylor and Francis Online.
The use of iterative algebraic methods applied to the reconstruction of computed tomography (CT) medical images is proliferating to reconstruct high-quality CT images using far fewer views than through analytical methods. This would imply reducing the dose of X-rays applied to patients who require this medical test. Least-squares methods are a promising approach to reconstruct the images with few projections obtaining high quality. In addition, since these techniques involve a high computational load, it is necessary to develop efficient methods that make use of high-performance-computing tools to accelerate reconstructions. In this paper, three least-squares methods are analyzed—Least-Squares Model Based (LSMB), Least-Squares QR (LSQR), and Least-Squares Minimal Residual (LSMR)—to determine whether the LSMB method provides faster convergence and thus lower computational times. Moreover, a block version of both the LSQR method and the LSMR method was implemented. With them, multiple right-hand sides (multiple slices) can be solved at the same time, taking advantage of the parallelism obtained with the implementation of the methods using the Intel Math Kernel Library. The two implementations are compared in terms of convergence, time, and quality of the images obtained, reducing the number of projections and combining them with a regularization and acceleration technique. The experiments show how the implementations are scalable and obtain images of good quality from a reduced number of views, with the LSQR method being better suited for this application.