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May 31–June 3, 2026
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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.
A. Ziya Akcasu, Larry D. Noble
Nuclear Science and Engineering | Volume 25 | Number 1 | May 1966 | Pages 47-57
Technical Paper | doi.org/10.13182/NSE66-A17500
Articles are hosted by Taylor and Francis Online.
Solutions of the point kinetic equations with delayed neutrons for reactor systems with arbitrary linear feedback are investigated. It is found that the solutions that are Laplace transformable are bounded for all initial perturbations regardless of whether or not the system is linearly stable, provided the Laplace transform of the feedback kernel has no zeros on the positive real axis. This criterion is applied to some reactor models previously investigated by others. It is shown that there are also nontransformable solutions that possess a finite escape time and that such solutions can exist only if the reactor has a prompt positive reactivity coefficient. The asymptotic behavior of these solutions near the escape time is also obtained. These general conclusions are verified by considering some specific feedback models for which exact solutions are available. Numerical solutions for reactor systems with more realistic feedback models, such as one used to describe EBR-I, are obtained by a digital computer.