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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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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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
NRC updating GEIS rule for new nuclear technology
The Nuclear Regulatory Agency is issuing a proposed generic environmental impact statement (GEIS) for use in reviewing applications for new nuclear reactors.
In an April 17 memo, NRC secretary Carrie Safford wrote that the commission approved NRC staff’s recommendation to publish in the Federal Register a proposed rule amending 10 CFR Part 51, “Environmental Protection Regulations for Domestic Licensing and Related Regulatory Functions.”
M. M. R. Williams
Nuclear Science and Engineering | Volume 193 | Number 4 | April 2019 | Pages 327-345
Technical Paper | doi.org/10.1080/00295639.2018.1531620
Articles are hosted by Taylor and Francis Online.
A number of approximate probability distribution functions (pdf’s) for the neutron density are examined with reference to low source startup. The most accurate method for determining the safe source strength, to reduce the likelihood of a rogue transient during startup, is that arising from the Pál-Bell equations. When these equations are extended to include space and energy dependence the numerical work becomes extensive. A pdf is developed which gives results that compare favorably with those from the exact solution but requires very much less numerical work. The method is applicable to space- and energy-dependent problems. Extensive numerical examples are given of the new method and of others which have been proposed over the years. In addition, we explore other approximations, unrelated to the generating function, that can lead to substantial computational savings. We have additionally described the principles behind, and provided a simple review of, the low source algorithm from which anyone unfamiliar with low source concepts can benefit.