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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.
G. Lansing Blackshaw, Raymond L. Murray
Nuclear Science and Engineering | Volume 27 | Number 3 | March 1967 | Pages 520-532
Technical Paper | doi.org/10.13182/NSE86-A17617
Articles are hosted by Taylor and Francis Online.
The elastic scattering of low-energy neutrons by the nuclei of a monatomic gas, which have an isotropic Maxwellian velocity distribution, is examined in detail within the framework of classical physics. A unified mathematical treatment, which fully preserves the three-dimensional aspects of the scattering process, is employed to study the dynamics of the neutron-nuclear elastic collision. A new form of the scattering probability function in velocity space is derived under the assumption of isotropic scattering in the center-of-mass system. Unique single-integral expressions, which are valid for any analytical or numerical representations of σs(υr) and σa(υr), the microscopic scattering and absorption cross section as functions of the relative neutron-nuclear speed, are developed for the velocity scattering kernel, its spherical-harmonics weighted moments, and the total scattering and absorption probabilities. These formulations are tested by explicitly evaluating them in closed form for certain analytical cross-section representations and comparing these solutions with known results. The utility of the collision kernels for new solutions of the transport equation under conditions of variable scattering cross section is discussed.
