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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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NN Asks: What did you learn from ANS’s Nuclear 101?
Mike Harkin
When ANS first announced its new Nuclear 101 certificate course, I was excited. This felt like a course tailor-made for me, a transplant into the commercial nuclear world. I enrolled for the inaugural session held in November 2024, knowing it was going to be hard (this is nuclear power, of course)—but I had been working on ramping up my knowledge base for the past year, through both my employer and at a local college.
The course was a fast-and-furious roller-coaster ride through all the key components of the nuclear power industry, in one highly challenging week. In fact, the challenges the students experienced caught even the instructors by surprise. Thankfully, the shared intellectual stretch we students all felt helped us band together to push through to the end.
We were all impressed with the quality of the instructors, who are some of the top experts in the field. We appreciated not only their knowledge base but their support whenever someone struggled to understand a concept.
Masahide Imasaki and Torao Yanaru
Nuclear Science and Engineering | Volume 33 | Number 1 | July 1968 | Pages 93-105
Technical Paper | doi.org/10.13182/NSE68-A20921
Articles are hosted by Taylor and Francis Online.
The stability of flux-shaped spatial modes is studied in a Calder Hall type reactor in three dimensions using the homogeneous boundary condition of the reactivity with the following three results: 1) the modal interaction due to coolant flow is also a second-order term in the three-dimensional modal analysis and can be ignored as the first approximation; 2) the Nyquist criterion should be applied to the expression containing the involved transcendental function in the transfer function of the thermal system; and 3) the simple thermal model, which treats only the fuel, moderator, and coolant, is adequate to judge the stability of the mode. The effects of flattening the radius on the threshold value of the moderator reactivity temperature coefficient and on the period of the sustained oscillation have been studied by this method as a function of the eigenvalue, and it has been shown that: 1) the modes with the same order in axial and radial direction form a group; and 2) the modes with the second order in axial direction are more stable than the modes with the first order in axial direction.
