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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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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Proving DRACO will deliver
The United States is now closer than it has been in over five decades to launching the first nuclear thermal rocket into space, thanks to DRACO—the Demonstration Rocket for Agile Cislunar Orbit.
Taro Ueki
Nuclear Science and Engineering | Volume 158 | Number 1 | January 2008 | Pages 15-27
Technical Paper | doi.org/10.13182/NSE08-A2735
Articles are hosted by Taylor and Francis Online.
On-the-fly diagnostics of the number of particles per iteration cycle in iterated-source Monte Carlo computation, which output diagnostic measures for a given spatial resolution of binning cells as iteration cycles progress, have been studied using relative entropy and chi-square distance. A source ratio vector is defined whose components are the ratio of the sources of adjacent iteration cycles at the individual binning cells. This enables one to define a problem-independent reference vector based on the integral equation representation of the static eigenvalue problem of particle multiplication. These vectors are normalized so that they represent discrete probability distribution. The relative entropy of the source ratio vector and the weighted difference between the relative entropy and the chi-square distance of the source ratio vector, all with respect to the reference vector, have been shown to be effective measures of particle population. Numerical examples presented include the initial core of a pressurized water reactor (PWR), the vault of PWR fresh fuel bundles, and the Whitesides' keff-of-the-world problem.