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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Empowering the next generation: ANS’s newest book focuses on careers in nuclear energy
A new career guide for the nuclear energy industry is now available: The Nuclear Empowered Workforce by Earnestine Johnson. Drawing on more than 30 years of experience across 16 nuclear facilities, Johnson offers a practical, insightful look into some of the many career paths available in commercial nuclear power. To mark the release, Johnson sat down with Nuclear News for a wide-ranging conversation about her career, her motivation for writing the book, and her advice for the next generation of nuclear professionals.
When Johnson began her career at engineering services company Stone & Webster, she entered a field still reeling from the effects of the Three Mile Island incident in 1979, nearly 15 years earlier. Her hiring cohort was the first group of new engineering graduates the company had brought on since TMI, a reflection of the industry-wide pause in nuclear construction. Her first long-term assignment—at the Millstone site in Waterford, Conn., helping resolve design issues stemming from TMI—marked the beginning of a long and varied career that spanned positions across the country.
Gokhan Corak, James A. Turso, Kenan Ünlu (Penn State)
Proceedings | Nuclear Plant Instrumentation, Control, and Human-Machine Interface Technolgies (NPIC&HMIT 2019) | Orlando, FL, February 9-14, 2019 | Pages 618-628
The safe and effective control of nuclear reactors is of significant interest to the research reactor community and nuclear power utility industry. Numerous advanced control algorithms have demonstrated superior reactor control over the past several decades – primarily on simulated reactors. Among these, state feedback control has been applied to virtually every type of dynamic system. This paper focuses on developing an accurate model of the Penn State TRIGA Reactor simulation and creating a state feedback controller/state observer design using self-powered Vanadium and Rhodium neutron detectors (SPND) as feedback sensors. This work is the first attempt to use these type of sensors in a closed-loop feedback system for reactor control. The foundation of the equations in Simulink has been derived from normalized point kinetics equations and core averaged thermal-hydraulic equations. The self-powered detector dynamics may be developed from basic activation/decay balance differential equations. Results demonstrate that the TRIGA Simulink model developed compares well with the actual TRIGA Reactor data. Self-powered neutron detectors are well-suited to monitor steady-state reactor power. Due to their dependence on radioactive decay after irradiation to produce a current signal, self-powered detectors have significant delay times associated with them, making them inadequate for real-time feedback control. The long delay associated with the normal detector models can only realistically be used for applications where this delay can be tolerated, such as post-accident power monitoring. A major contribution of this paper is the development and application of detector inverse models, which null-out delays introduced by the physics of the detector. Results demonstrate that the inverse detector models have no delay which is desirable for the reactor closed-loop control. SPNDs need no external power to produce current levels consistent with ion chambers and may prove to be a vital component for closed-loop nuclear reactor control in the future. The successful application of an advanced control algorithm i.e., state-feedback control with self-powered neutron detectors, demonstrates that this technology may be applied in closed-loop nuclear reactor control and safety systems not only for power plant applications but for applications such as space nuclear reactors as well.
