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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Chris Wagner: The role of Eden Radioisotopes in the future of nuclear medicine
Chris Wagner has more than 40 years of experience in nuclear medicine, beginning as a clinical practitioner before moving into leadership roles at companies like Mallinckrodt (now Curium) and Nordion. His knowledge of both the clinical and the manufacturing sides of nuclear medicine laid the groundwork for helping to found Eden Radioisotopes, a start-up venture that intends to make diagnostic and therapeutic raw material medical isotopes like molybdenum-99 and lutetium-177.
John A. Bernard, David D. Lanning
Nuclear Science and Engineering | Volume 110 | Number 4 | April 1992 | Pages 425-444
Technical Paper | doi.org/10.13182/NSE92-A23916
Articles are hosted by Taylor and Francis Online.
Factors relevant to the design and implementation of digital controllers for research reactors are discussed with emphasis on the rationale for incorporating a system model in the control law. For this purpose, proportional-integral-derivative and period-generated control are compared. The latter is a model-based technique that achieves excellent trajectory tracking of nonlinear systems. It does this by combining feedback and feedforward control action in a manner that cancels the effects of the system’s dynamics on the controller’s performance. Model-based control is also superior in that it permits replication of some of the functions that humans perform when exercising control. In particular, models can be used to predict expected plant response and thereby facilitate diagnosis. The importance of validated signals, supervisory algorithms, properly designed man-machine interfaces, and automated diagnostics are discussed in relation to control law implementation. In addition, a summary is provided of reactor dynamics as related to control, and arguments are presented in support of using the rate of change of reactivity as the actuator signal. Experimental results obtained from trials of digital controllers on both the 5-MW(thermal) Massachusetts Institute of Technology Research Reactor and the Annular Core Research Reactor that is operated by Sandia National Laboratories are included.