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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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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.
D. F. Da Cruz, D. Rochman, A. J. Koning
Nuclear Technology | Volume 185 | Number 2 | February 2014 | Pages 174-191
Technical Paper | Fuel Cycle And Management | doi.org/10.13182/NT12-154
Articles are hosted by Taylor and Francis Online.
Uncertainty analysis on reactivity and discharged inventory for a typical pressurized water reactor fuel element as a result of uncertainties in 235,238U, 239,240,241Pu, and fission products nuclear data was performed. A typical Westinghouse three-loop fuel assembly fueled with UO2 fuel with 4.8% enrichment was selected. The Total Monte Carlo method was applied using the deterministic transport code DRAGON. This code allows the generation of the few-groups nuclear data libraries by directly using data contained in the nuclear data evaluation files. The nuclear data used in this study are from the JEFF3.1 evaluation, with the exception of the nuclear data files for U, Pu, and fission products isotopes (randomized for the generation of the various DRAGON libraries). These are taken from the TALYS evaluated nuclear data library TENDL-2012. Results show that the calculated total uncertainty in keff (as a result of uncertainties in nuclear data of the considered isotopes) is virtually independent of fuel burnup, and amounts to 700 pcm. The uncertainties in the inventory of the discharged fuel are dependent on the element considered and lie in the range 1% to 15% for most fission products, and are <5% for the most important actinides. The total uncertainty on the reactor parameters was also split into different components (different nuclear reaction channels), and the main sources of uncertainties were identified.
