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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Reflections on NOW
Hash Hasemianpresident@ans.org
Last month, I talked about my goal of strengthening ANS’s voice, in part by attending three conferences. I have now checked the first event off that list: the Nuclear Opportunities Workshop.
This year, NOW took another step in outgrowing its “workshop” moniker and transitioning to a full-fledged regional conference and expo. What started only a few years ago as a small gathering in Oak Ridge, Tenn., with roughly 50 attendees has skyrocketed to an event with 1,100 people in attendance in Knoxville.
NOW’s popularity reflected how busy the roughly 350 nuclear companies in Tennessee have been in recent years. There is significant work going on surrounding Gen IV reactor development and deployment, advancements in new nuclear fuels, and defense-related builds like the Uranium Processing Facility.
John C. Wagner, Douglas E. Peplow, Thomas M. Evans
Nuclear Technology | Volume 168 | Number 3 | December 2009 | Pages 799-809
MC Calculations | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Protection | doi.org/10.13182/NT09-A9309
Articles are hosted by Taylor and Francis Online.
Simulating nuclear well-logging devices with Monte Carlo methods is computationally challenging and requires significant variance reduction to compute detector responses with low statistical uncertainties in reasonable lengths of time. The consistent adjoint-driven importance sampling (CADIS) method, which provides consistent source and transport biasing parameters based on a deterministic adjoint (importance) function, has been demonstrated to be very effective for well-logging simulations and other deep-penetration problems. A recent extension to the CADIS method, FW-CADIS (forward-weighted CADIS), is designed to optimize the calculation of several tallies at once by using an adjoint function based on an adjoint source weighted by the inverse of the forward flux. These advanced variance reduction methods have been incorporated and automated into the MAVRIC sequence of SCALE, making them very easy to use. The CADIS and FW-CADIS methods are demonstrated and compared on simple benchmark models of both neutron- and photon-based well-logging devices. Both advanced variance reduction methods offer a substantial reduction in computing time, compared to analog simulation, for these applications.