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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Hash Hashemian: Visionary leadership
As Dr. Hashem M. “Hash” Hashemian prepares to step into his term as President of the American Nuclear Society, he is clear that he wants to make the most of this unique moment.
A groundswell in public approval of nuclear is finding a home in growing governmental support that is backed by a tailwind of technological innovation. “Now is a good time to be in nuclear,” Hashemian said, as he explained the criticality of this moment and what he hoped to accomplish as president.
D. G. Cacuci, J.J. Wagschal, A. Yaari
Nuclear Science and Engineering | Volume 81 | Number 3 | July 1982 | Pages 443-450
Technical Paper | doi.org/10.13182/NSE82-A20285
Articles are hosted by Taylor and Francis Online.
The concept of a leakage importance function is introduced and analyzed for physical systems governed by the Boltzmann transport equation. The homogeneous equation with inhomogeneous boundary conditions satisfied by the importance function is derived by using adjoint operators. A standard discrete ordinates transport code is used to solve this equation, and some important numerical aspects are highlighted. Idealized nuclear systems are analyzed to illustrate that the leakage importance function gives a measure of the relative importance of each source particle in phase space in contributing to the leakage, and that the leakage importance function provides insight regarding the specific physical process that leads to leakage.
