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The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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NRC restores expiration dates for renewed Turkey Point licenses
The Nuclear Regulatory Commission announced this week that it has restored the expiration dates of the Turkey Point nuclear power plant's units 3 and 4 subsequent license renewals (SLR) to July 19, 2052, and April 10, 2053, respectively.
M. M. R. Williams
Nuclear Science and Engineering | Volume 143 | Number 1 | January 2003 | Pages 1-18
Technical Paper | doi.org/10.13182/NSE03-A2314
Articles are hosted by Taylor and Francis Online.
A model of neutron multiplication for aggregates of randomly placed fissile spheres with random material properties in a background medium is presented in terms of the transport equation. Two distinct problems are examined: (1) small spheres in an infinite bulk medium in which the total cross section in the spheres and bulk medium are the same and (2) small spheres in a void or purely absorbing medium but with different total cross sections in sphere and medium. In both cases we consider criticality in which there are random material properties of the spheres and random positions in the container. The random sphere problem is studied statistically by calculating the multiplication factor for many thousands of cases with different positions and material properties and, from the results, constructing a probability distribution function for the multiplication factor. Some of the results are also calculated using diffusion theory and therefore we are able to give guidance on the likely errors caused by diffusion theory in this type of problem.Although the problems are restricted to the one speed approximation, they may be applicable to fast neutron problems and we apply the work to spheres composed of random proportions of 235U and 238U. The work also has some bearing on the physical behaviour of pebble bed reactors which are of current interest, and in the storage of fissile waste. We have also discussed some of the underlying statistical problems associated with random arrays of spheres in a uniform lattice. In formulating our problem, we use the collision probability technique and as a by-product derive some new inter-lump collision probabilities for two spheres.