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Conference Spotlight
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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
What’s the most difficult question you’ve been asked as a maintenance instructor?
Blye Widmar
"Where are the prints?!"
This was the final question in an onslaught of verbal feedback, comments, and critiques I received from my students back in 2019. I had two years of instructor experience and was teaching a class that had been meticulously rehearsed in preparation for an accreditation visit. I knew the training material well and transferred that knowledge effectively enough for all the students to pass the class. As we wrapped up, I asked the students how they felt about my first big system-level class, and they did not hold back.
“Why was the exam from memory when we don’t work from memory in the plant?” “Why didn’t we refer to the vendor documents?” “Why didn’t we practice more on the mock-up?” And so on.
James J. Duderstadt
Nuclear Science and Engineering | Volume 33 | Number 1 | July 1968 | Pages 119-127
Technical Paper | doi.org/10.13182/NSE68-A20923
Articles are hosted by Taylor and Francis Online.
The propagation of neutron waves in polycrystalline moderators is analyzed via a modeled velocity-dependent transport theory. Analytical results are made possible by the use of a simple model of the scattering kernel. Particular attention is devoted to the interpretation of neutron wave experiments performed in graphite parallelepipeds. It is found that, while a plane wave mode is not always dominant asymptotically in polycrystalline materials, a meaningful experiment can be performed provided certain restrictions on detector position and source frequency are observed.
