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Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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Countering the nuclear workforce shortage narrative
James Chamberlain, director of the Nuclear, Utilities, and Energy Sector at Rullion, has declared that the nuclear industry will not have workforce challenges going forward. “It’s time to challenge the scarcity narrative,” he wrote in a recent online article. “Nuclear isn't short of talent; it’s short of imagination in how it attracts, trains, and supports the workforce of the future.”
T. Otsuka, N. Fukumura, Y. Hachiya
Nuclear Science and Engineering | Volume 74 | Number 2 | May 1980 | Pages 95-105
Technical Paper | doi.org/10.13182/NSE80-A19626
Articles are hosted by Taylor and Francis Online.
The moderator temperature coefficients of reactivity for a pressure-tube-type reactor consisting of highly heterogeneous cells with D2O moderator, H2O coolant, and 28-pin fuel cluster contained in a pressure-tube have been measured in order to clarify their dependence on the moderator temperature. A new experimental method has been developed that is applicable to ordinary critical assemblies not equipped with any special temperature control system. In this method, temperature changes of the core, which is subjected to natural cooling that permits heat transfer from the moderator to the H2O coolant, are measured continually, together with the resultant changes in reactivity. The data are analyzed with use of least-squares fitting to nonlinear functions. It has been clarified that the moderator temperature coefficient of reactivity of this type of reactor is markedly dependent on the moderator temperature, decreasing with increase in the temperature. In a clean lattice of 1.2 wt% 235U enriched UO2 fuel that contains no 10B in the moderator, the coefficient changes its sign from positive to negative at ∼40°C. Addition of 3.9 ppm of 10B into the D2O moderator of the same lattice causes the value of the temperature coefficient to shift considerably toward the positive side. Calculational results by the WIMS code reproduce quite well the experimental values of the temperature dependence of the moderator temperature coefficient of reactivity. However, their absolute values are rather small compared to the experimental ones.