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Young Members Group
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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Materials in Nuclear Energy Systems (MiNES 2023)
December 10–14, 2023
New Orleans, LA|New Orleans Marriott
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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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First container of test glass filled at Hanford’s Vit Plant
Bechtel and the Department of Energy’s Office of Environmental Management announced on December 4 that the first set of test glass was successfully poured into a stainless-steel storage container designed to hold vitrified waste at Hanford’s Waste Treatment and Immobilization Plant, also known as the Vit Plant.
J. Barhen, D. G. Cacuci, J. J. Wagschal, M. A. Bjerke, C. B. Mullins
Nuclear Science and Engineering | Volume 81 | Number 1 | May 1982 | Pages 23-44
Technical Paper | doi.org/10.13182/NSE82-3
Articles are hosted by Taylor and Francis Online.
An advanced methodology for performing systematic uncertainty analysis of time-dependent nonlinear systems is presented. This methodology includes a capability for reducing uncertainties in system parameters and responses by using Bayesian inference techniques to consistently combine prior knowledge with additional experimental information. The determination of best estimates for the system parameters, for the responses, and for their respective covariances is treated as a time-dependent constrained minimization problem. Three alternative formalisms for solving this problem are developed. The two “off-line” formalisms, with and without “foresight” characteristics, require the generation of a complete sensitivity data base prior to performing the uncertainty analysis. The “online” formalism, in which uncertainty analysis is performed interactively with the system analysis code, is best suited for treatment of large-scale highly nonlinear time-dependent problems. This methodology is applied to the uncertainty analysis of a transient upflow of a high pressure water heat transfer experiment. For comparison, an uncertainty analysis using sensitivities computed by standard response surface techniques is also performed. The results of the analysis indicate the following. 1. Major reduction of the discrepancies in the calculation/experiment ratios is achieved by using the new methodology. 2. Incorporation of in-bundle measurements in the uncertainty analysis significantly reduces system uncertainties. 3. Accuracy of sensitivities generated by response-surface techniques should be carefully assessed prior to using them as a basis for uncertainty analyses of transient reactor safety problems. Conclusions about the future applicability of the uncertainty analysis methodology presented in this work are also discussed.