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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.
Vladimir A. Babenko, Laszlo L. Jenkovszky, Volodymyr A. Romanov, Volodymyr N. Pavlovych, Oleg Ya. Vertsimakha
Nuclear Science and Engineering | Volume 133 | Number 3 | November 1999 | Pages 301-313
Technical Paper | doi.org/10.13182/NSE99-A2090
Articles are hosted by Taylor and Francis Online.
The results are presented of an investigation of the multiplying properties of lava-formed fuel-containing masses (LFCM); also, the possibility of developing ignition and dynamics of a self-sustaining chain reaction (SCR) in the LFCM of the destroyed Unit 4 of the Chernobyl nuclear power plant (the so-called Shelter) is discussed. The SCALE 4.3 computer code was used to calculate the multiplication factor, the neutron energy spectrum, the spatial distribution of the neutron flux density, etc., as functions of the water content in the LFCM for different system models. These results can help to determine the optimum placement of detectors in the rooms under the reactor. In addition, the dynamic of an SCR under the hypothetical condition that the filling of the LFCM by water leads to an excess multiplication factor over unity was considered. Such a treatment was performed for a simple model that takes into account the evaporation of water and an increase in temperature due to an energy release in the LFCM. The different modes of the LFCM behavior depending on the velocity of water filling are discussed.
