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2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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AI at work: Southern Nuclear’s adoption of Copilot agents drives fleet forward
Southern Nuclear is leading the charge in artificial intelligence integration, with employee-developed applications driving efficiencies in maintenance, operations, safety, and performance.
The tools span all roles within the company, with thousands of documented uses throughout the fleet, including improved maintenance efficiency, risk awareness in maintenance activities, and better-informed decision-making. The data-intensive process of preparing for and executing maintenance operations is streamlined by leveraging AI to put the right information at the fingertips for maintenance leaders, planners, schedulers, engineers, and technicians.
U. Hansen, E. Teuchert
Nuclear Science and Engineering | Volume 44 | Number 1 | April 1971 | Pages 12-17
Technical Paper | doi.org/10.13182/NSE44-12
Articles are hosted by Taylor and Francis Online.
The heterogeneity due to lumping the fuel in coated particles affects the thermal-neutron spectrum. A calculational model is discussed which, apart from some simplifying assumptions about the statistical distribution, allows a rigorous computation of effective cross sections for all nuclides of the heterogeneous medium. It is based on an exact computation of the neutron-penetration probability through coating and kernel. The model is incorporated in a THERMOS code providing a double heterogeneous cell calculation that can be repeated automatically at different time steps in the depletion code system MAFIA-V.S.O.P. A discussion of the effects of the coated-particle structure is given by a comparison of calculations for heterogeneous and homogeneous fuel zones in pebble bed reactor elements. This is performed for enriched UO2 fuel and for a ThO2-PuO2 mixture in the grains. Depending on the energy-dependent total sigmas in the kernels, the changes of the cross sections range from 0.1 up to 45%. The influence on the spectrum-averaged sigmas of the nuclides in the fresh UO2 fuel is lower than 1%. For the emerging 240Pu it increases up to 3.3% during irradiation. For the ThO2-PuO2 fuel, the averaged sigmas of the isotopes vary from 0.5 to 5.7% depending on the state of irradiation. Correspondingly, there is an influence on the plutonium isotopic composition, on breeding ratios, and on the tilt of keff during burnup which will be discussed in detail.
