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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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Latest News
Standard Nuclear executes OTA with DOE
Reactor-agnostic TRISO fuel producer Standard Nuclear recently announced that it has executed an other transaction agreement (OTA) with the Department of Energy. As one of the five companies involved in the DOE’s Fuel Line Pilot Program, its entrance into this deal marks a milestone in the public-private effort to bring advanced fuel production on line in support of the DOE’s concurrently running Reactor Pilot Program.
David J. Kropaczek, Ryan Walden
Nuclear Science and Engineering | Volume 193 | Number 5 | May 2019 | Pages 523-536
Technical Paper | doi.org/10.1080/00295639.2018.1550970
Articles are hosted by Taylor and Francis Online.
The constraint annealing method is presented and demonstrated for the solution of large-scale, multiconstrained problems in light water reactor fuel cycle optimization. Constraint annealing is a penalty-free method that eliminates the need for traditional constraint weighting factors by treating each objective function and constraint as separate and concurrently solved minimization problems within a global optimization search framework. The current application seeks to demonstrate the effectiveness of constraint annealing for a complex core loading pattern design problem containing multiple objective functions and constraints without the need for additional ad hoc control parameters. Two problems of varying degrees of complexity are analyzed. The first problem is defined by a single objective function based on maximizing cycle energy with two constraints based on power peaking and peak rod exposure. The second problem expands upon the first by adding an additional objective function for vessel fluence and four additional constraints based on controlled power peaking, steaming rate, moderator temperature coefficient, and alternate source term. Results demonstrate that constraint annealing inherently addresses issues of scaling associated with different objective function and constraint formulations as well as the impact on cycle energy.