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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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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BREAKING NEWS: Trump issues executive orders to overhaul nuclear industry
The Trump administration issued four executive orders today aimed at boosting domestic nuclear deployment ahead of significant growth in projected energy demand in the coming decades.
During a live signing in the Oval Office, President Donald Trump called nuclear “a hot industry,” adding, “It’s a brilliant industry. [But] you’ve got to do it right. It’s become very safe and environmental.”
Bo Shi, Bojan Petrovic
Nuclear Science and Engineering | Volume 172 | Number 2 | October 2012 | Pages 138-150
Technical Paper | doi.org/10.13182/NSE11-19
Articles are hosted by Taylor and Francis Online.
The Monte Carlo method is widely used to compute the fundamental eigenfunction and eigenvalue for nuclear systems. However, the standard power iteration method computes only the fundamental eigenmode, while it would be beneficial to also compute the higher eigenfunctions and eigenvalues to support the reactor transient analysis, stability analysis, and assessments of nuclear safety, as well as to enable certain source convergence acceleration techniques. Modifications to the power method have been developed that in principle can accomplish this goal, but they typically lead to unphysical positive and negative particles requiring a procedure to compute the net-weight deposition. In this paper, we present a new mechanism that enables the Monte Carlo procedure, with certain modifications, to compute the second eigenfunction and eigenvalue for one-dimensional (1-D) problems. The method could in principle be extended to higher harmonics and general geometries. The results from numerical examples, including a 1-D, two-group, multiregion example, are consistent with reference results. Moreover, the extra computational cost of this method is of the same order of magnitude as the conventional Monte Carlo simulations. This method can be applied solely to solve for the high eigenmodes, or implemented as a part of a net-weight computation mechanism when negative particles are present in the modified power iteration method.