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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
Standards Program
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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Nuclear Science and Engineering
February 2025
Nuclear Technology
January 2025
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Latest News
Reboot: Nuclear needs a success . . . anywhere
The media have gleefully resurrected the language of a past nuclear renaissance. Beyond the hype and PR, many people in the nuclear community are taking a more measured view of conditions that could lead to new construction: data center demand, the proliferation of new reactor designs and start-ups, and the sudden ascendance of nuclear energy as the power source everyone wants—or wants to talk about.
Once built, large nuclear reactors can provide clean power for at least 80 years—outlasting 10 to 20 presidential administrations. Smaller reactors can provide heat and power outputs tailored to an end user’s needs. With all the new attention, are we any closer to getting past persistent supply chain and workforce issues and building these new plants? And what will the election of Donald Trump to a second term as president mean for nuclear?
As usual, there are more questions than answers, and most come down to money. Several developers are engaging with the Nuclear Regulatory Commission or have already applied for a license, certification, or permit. But designs without paying customers won’t get built. So where are the customers, and what will it take for them to commit?
Sergio Guarro, David Okrent
Nuclear Technology | Volume 67 | Number 3 | December 1984 | Pages 348-359
Technical Paper | Fission Reactor | doi.org/10.13182/NT84-A33494
Articles are hosted by Taylor and Francis Online.
Logic flowgraph methodology (LFM) is intended to provide a more efficient way of constructing failure models for use in a diagnosis oriented disturbance analysis system. The LFM approach represents a considerable development beyond previous methods and also may be useful in reliability and risk analysis applications. Like the digraph method, LFM produces process models in which the fundamental units of nodes and edges are used to represent process variables and causality relations, respectively. In LFM, however, a more extended set of representation rules allows one to achieve a greater level of modeling capability and flexibility. The LFM models hinge on the interconnection of two distinct networks, namely, the “causality network” and the “condition network.” In a formally defined and organized way the condition network represents the conditions whose occurrence can change or modify the course of process causality flow in the causality network. A test case demonstrates the applicability of LFM to situations of interest in nuclear power plant operation and also shows that once a suitable process flow graph model has been derived, it is possible to obtain any fault-tree structure whose top event can be expressed as a weak or strong perturbation on one of the variables constituting a flowgraph node. This fault-tree construction is performed automatically by a computer routine, accepting as input the logic flowgraph topology and the top event of the desired fault tree. In a disturbance analysis application, this routine also accepts as input a set of field instrumentation signals; using this information on line identifies within a fraction of a second the prime cause of the disturbance by logically developing only those tree branches that the instrumentation indicates as active. In reliability or risk analysis applications, on the contrary, the desired fault tree is developed to its full extent.