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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Frisch-Peierls memorandum: A seminal document of nuclear history
The Manhattan Project is usually considered to have been initiated with Albert Einstein’s letter to President Franklin Roosevelt in October 1939. However, a lesser-known document that was just as impactful on wartime nuclear history was the so-called Frisch-Peierls memorandum. Prepared by two refugee physicists at the University of Birmingham in Britain in early 1940, this manuscript was the first technical description of nuclear weapons and their military, strategic, and ethical implications to reach high-level government officials on either side of the Atlantic. The memorandum triggered the initiation of the British wartime nuclear program, which later merged with the Manhattan Engineer District.
Nafisah Khan, Lixuan Lu
Nuclear Technology | Volume 172 | Number 3 | December 2010 | Pages 278-286
Technical Paper | Instrumentation and Control Systems | doi.org/10.13182/NT10-A10936
Articles are hosted by Taylor and Francis Online.
This paper presents a decoupling algorithm for a large pressurized heavy water reactor to facilitate the design of a decentralized control system. The reactor models are generally high-order systems, which increases the difficulty of designing control systems. A convenient method of model reduction while maintaining the important dynamic characteristics of the process is through decoupling. The new decoupling algorithm proposed in this paper is used to create a decoupled system for decentralized controller design. To demonstrate the performance of this algorithm, a 72nd-order system was decoupled into three partitions, each containing 20, 27, and 25 states. Both a centralized controller based on the original model and decentralized controllers based on the decoupled model are designed. The advantage of the decentralized controller is shown through a fail-safe study.
