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The human factor in licensing and operating the next generation of nuclear plants
As human factors specialists working at the intersection of human performance and nuclear operations, we are witnessing one of the nuclear sector’s most significant transitions in decades. The emergence of small modular reactors, microreactors, and other advanced designs is reshaping the industry’s landscape. Digital instrumentation and controls, passive safety systems, and increased automation are creating opportunities for greater safety margins and more flexible operation. These same features also fundamentally redefine what it means to “operate” a nuclear plant. Interactions among human roles, automation, and passive systems shape how people maintain awareness, exercise judgment, and intervene when necessary. These developments affect both operational realities and the regulatory foundations on which nuclear safety is built.
Jae-Woong Song, Jong-Kyung Kim
Nuclear Technology | Volume 103 | Number 2 | August 1993 | Pages 157-167
Technical Paper | Fission Reactor | doi.org/10.13182/NT93-A34840
Articles are hosted by Taylor and Francis Online.
An efficient nodal method for the solution of two-group, multidimensional neutron kinetics problems is presented. In this method, correction factors called discontinuity factors are calculated in advance by the nodal expansion method (NEM) at steady-state conditions, and the nodewise flux and power distributions during steady-state and transient conditions are calculated based on the discontinuity factors. The nodal balance equation using the discontinuity factors is expressed logically in a less complicated manner than in other nodal methods since the factors reflect all of the approximations, including classic spatial truncations. Additionally, the convergence of the transient problem can be greatly accelerated through a thermal leakage-to-absorption ratio (TLAR) scheme. The test results for the two-group, two-dimensional benchmark problems demonstrate that this new method has acceptable accuracy and is about two times faster without the TLAR scheme and about ten times faster with the TLAR scheme than other nodal methods (NEM or analytic nodal method) for transient applications in which assemblysize coarse nodes are used.