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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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NN Asks: What did you learn from ANS’s Nuclear 101?
Mike Harkin
When ANS first announced its new Nuclear 101 certificate course, I was excited. This felt like a course tailor-made for me, a transplant into the commercial nuclear world. I enrolled for the inaugural session held in November 2024, knowing it was going to be hard (this is nuclear power, of course)—but I had been working on ramping up my knowledge base for the past year, through both my employer and at a local college.
The course was a fast-and-furious roller-coaster ride through all the key components of the nuclear power industry, in one highly challenging week. In fact, the challenges the students experienced caught even the instructors by surprise. Thankfully, the shared intellectual stretch we students all felt helped us band together to push through to the end.
We were all impressed with the quality of the instructors, who are some of the top experts in the field. We appreciated not only their knowledge base but their support whenever someone struggled to understand a concept.
Jeremy Lloyd Conlin, James Paul Holloway
Nuclear Science and Engineering | Volume 169 | Number 2 | October 2011 | Pages 168-177
Technical Paper | doi.org/10.13182/NSE10-72
Articles are hosted by Taylor and Francis Online.
This paper introduces the explicitly restarted Arnoldi's method for calculating eigenvalues and eigenvectors in a Monte Carlo criticality calculation. Arnoldi's method is described along with the power method. The power method has been used for decades for Monte Carlo criticality calculations despite the availability of other algorithms with better convergence properties. The Monte Carlo application of the transport-fission operator of the Boltzmann transport equation is defined, and the Monte Carlo implementation of both Arnoldi's method and the power method are described. A brief discussion of eigenvalue and fission source convergence is given. Numerical simulations of one-demensional slab geometries are presented, demonstrating the convergence of both the eigenvalue and fission source (as measured by the Shannon entropy) for both Arnoldi's method and the power method. The results show that Arnoldi's method does not need to discard iterations like the power method because both the eigenvalue and fission source appear to converge immediately, even for problems with high dominance ratios.