ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
2022 ANS Annual Meeting
June 12–16, 2022
Anaheim, CA|Anaheim Hilton
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!
Latest Magazine Issues
Latest Journal Issues
Nuclear Science and Engineering
Fusion Science and Technology
NNSA issues Mo-99 cooperative agreement to Niowave
The Department of Energy’s National Nuclear Security Administration has issued a cooperative agreement worth $13 million to Niowave, of Lansing, Mich., to support the commercial production of molybdenum-99, a critical isotope used in more than 40,000 medical procedures in the United States each day, including the diagnosis of heart disease and cancer.
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 | dx.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.