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Mathematics & Computation
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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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
M. M. R. Williams
Nuclear Science and Engineering | Volume 136 | Number 1 | September 2000 | Pages 34-58
Technical Paper | doi.org/10.13182/NSE00-A2146
Articles are hosted by Taylor and Francis Online.
A general formulation is developed for calculating the mean neutron flux in spatially random media. It is based upon Keller's first order smoothing approximation and starts from the integral form of the transport equation in which the number densities of the various nuclear species are considered as stationary random variables. The mean flux is shown to be described by a linear integral equation. In some special cases this has been solved. In particular, for a purely absorbing medium we calculate the flux in the neighborhood of point, line and plane sources and demonstrate the importance of the degree of anisotropy in the correlation function. We also obtain an analytical expression for the collision probability in a spatially random medium and compare this with its deterministic analog.An explicit solution for the mean flux in an infinite medium is obtained in terms of a general source distribution using Fourier transforms. Using image pile theory we are able to calculate the effect of randomness on the critical size of a body. We can show that, for a fissile material, spatial randomness always increases the reactivity of the mixture.