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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Kadir Kavaklioglu, Belle R. Upadhyaya
Nuclear Technology | Volume 125 | Number 1 | January 1999 | Pages 70-84
Technical Paper | Reactor Operations and Control | doi.org/10.13182/NT99-A2933
Articles are hosted by Taylor and Francis Online.
A methodology for designing membership functions for fuzzy controllers has been developed and demonstrated with application to feedwater heater level control. This method, namely simulated annealing, assumes that the rule base is determined by an expert who is knowledgeable about the process to be controlled. Although this method is applicable to any type of fuzzy controller, max-min center-average fuzzy controllers with triangular and trapezoidal membership functions were used due to the ease of implementation of this combination. This method essentially performs a random search for the parameters of the membership functions that yield the minimum squared error between the plant outputs and their setpoints for a given test signal as a disturbance. A major dimensionality reduction is accomplished through the identification of some requirements on membership functions. A significant improvement is made in handling membership function constraints that allows the use of every generated solution in the search process. The proposed methodology was applied to the control of cascade-arranged feedwater heaters that are currently controlled by individual pneumatic proportional-only controllers. An optimal fuzzy control system was developed for controlling the levels in this system for a typical load-following transient. The optimal fuzzy controller was found to improve rise time and settling time and to decrease the overshoot in the desired level.