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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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A year ago this month, Amazon led a $500 million investment in X-energy, alongside Citadel founder Ken Griffin, the University of Michigan, and other investors. In addition to that financing, Amazon pledged to support the development of an initial four-unit, 320-MW project with Energy Northwest in Washington state.
G. R. Dalton
Nuclear Science and Engineering | Volume 20 | Number 2 | October 1964 | Pages 131-137
Technical Paper | doi.org/10.13182/NSE64-A28926
Articles are hosted by Taylor and Francis Online.
A method of doing PN calculations which is particularly useful for classroom use is presented. The method is basically a systematic numerical implementation of the analytic method of characteristic solutions. The extensive tabulations of characteristic roots are used as guide lines for the solution of the characteristic (N + 1) order polynomial equation. Then the tables of coupling coefficients are used to guide the evaluation of the coupling or recursion relations. The systematics of matrix algebra is next used to set up the linear equations resulting from the boundary conditions and to reconstruct the angular moments and the angular fluxes. The use of these tabulated guide lines and matrix operations to provide the single and double summations reduces the problem to a very managable level. A sample P3 problem treated in this manner is presented.