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Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Nuclear News 40 Under 40 discuss the future of nuclear
Seven members of the inaugural Nuclear News 40 Under 40 came together on March 4 to discuss the current state of nuclear energy and what the future might hold for science, industry, and the public in terms of nuclear development.
To hear more insights from this talented group of young professionals, watch the “40 Under 40 Roundtable: Perspectives from Nuclear’s Rising Stars” on the ANS website.
Zbigniew Weiss
Nuclear Science and Engineering | Volume 48 | Number 3 | July 1972 | Pages 235-247
Technical Paper | doi.org/10.13182/NSE72-A22482
Articles are hosted by Taylor and Francis Online.
In one-dimensional systems which consist of N nodes, the two N response matrix equations for the partial currents through the node interfaces have been transformed into a set of N three-point equations with the total in-current per node as the new variable. The resulting coefficients which describe the coupling between neighboring nodes are expressed in terms of the reflection and transmission matrices of the invariant imbedding theory. These coupling coefficients can be compared with those of other nodal equations. In the case of slab geometry this has been illustrated by a direct comparison with the familiar finite difference formulation with the average flux per node as the dependent variable. Also the relation between the method presented here and the so-called rigorous finite difference equations has been established. The advantage of this method lies in the fact that the flexibility of the response matrix methods—which describe the nodes in terms of invariant imbedding concepts—has been condensed into the conventional three-point finite difference scheme, for which many well-established solution methods exist.