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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.
Bernard I. Spinrad, Zekeriya Altaç
Nuclear Science and Engineering | Volume 106 | Number 4 | December 1990 | Pages 480-488
Technical Paper | doi.org/10.13182/NSE90-A23772
Articles are hosted by Taylor and Francis Online.
The SKN approximation is slightly altered to solve the integral transport equation for heterogeneous systems. The original formulation of the SKN approximation has a defect when applied to heterogeneous problems. We propose a correction technique for such problems, which can also be applied to problems with P1 scattering. Such modified SKN equations are derived and tested for benchmark problems in one-dimensional geometries, which contain strong heterogeneities. Two-dimensional heterogeneous problems are solved using the unaltered SKN method with naive boundary conditions to determine how much heterogeneity can be tolerated before the remedy is necessary.
