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Conference Spotlight
2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
Hugh K. Clark
Nuclear Science and Engineering | Volume 20 | Number 3 | November 1964 | Pages 307-313
Technical Paper | doi.org/10.13182/NSE64-A19574
Articles are hosted by Taylor and Francis Online.
Calculations of the critical sizes of cubic arrays of interacting fissionable units are compared with critical experiments. The units are of two types: vessels containing 5 liters of an aqueous solution of highly enriched uranium, and cylinders of highly enriched uranium metal. The arrays are surrounded by various thicknesses of hydrogenous reflectors. Agreement between calculation and experiment is reasonably good. The similarity of the results obtained with the widely differing types of units invites confidence in general applications of the method of calculation. Tables are presented for computing critical and safe sizes of cubic arrays of 8, 27, 64, or 125 identical units as a function of the albedo of the reflector surrounding the array and of the reactivity of an individual unit.
