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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
Tong Kyu Park, Han Gyu Joo, Chang Hyo Kim
Nuclear Science and Engineering | Volume 176 | Number 2 | February 2014 | Pages 226-239
Technical Paper | doi.org/10.13182/NSE12-41
Articles are hosted by Taylor and Francis Online.
The multiobjective simulated annealing (MOSA)–based fuel assembly loading pattern (LP) optimization method, employing the discontinuous penalty function (DPF), is extended for multicycle applications by introducing an adaptively constrained discontinuous penalty function (ACDPF). A discontinuous point in the penalty function is adaptively shifted to a better direction during the course of MOSA such that the search can be more efficient. The advantages of the ACDPF-based MOSA algorithm over the original DPF-based algorithm are first examined with a real single-cycle LP optimization problem of an operating reactor, as well as with a simple LP optimization problem that has known solutions. A direct multicycle LP optimization method is then formulated with an application to the first four cycles of the Younggwang Nuclear Unit 4 (YGN4) core. The rearrangement method is devised as a fuel shuffling method that can avoid drastic changes in the LPs of the subsequent cycles of a seed cycle. It is demonstrated that the ACDPF-based MOSA combined with the rearrangement method produces quite effectively the optimum LP sets for the four cycles, which outperform the LPs generated by a series of cyclewise optimizations as well as the actual LPs of YGN4 that were already used in the plant.