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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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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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Latest News
NRC’s David Wright visits the Hill and more NRC news
Wright
The Nuclear Regulatory Commission is in the spotlight today for three very different reasons. First, NRC Chair David Wright was on the Hill yesterday for his renomination hearing in front of the Senate’s Environment and Public Works Committee. Second, the NRC released its updated milestone schedules according to the Nuclear Energy Innovation and Modernization Act (NEIMA) and the executive orders signed by President Trump last month; and third, as reported by Reuters on Tuesday, 28 former NRC officials have condemned the dismissal of Commissioner Hanson earlier this month.
Simone Santandrea
Nuclear Science and Engineering | Volume 155 | Number 2 | February 2007 | Pages 223-235
Technical Paper | Mathematics and Computation, Supercomputing, Reactor Physics and Nuclear and Biological Applications | doi.org/10.13182/NSE155-223
Articles are hosted by Taylor and Francis Online.
This paper presents recent developments of the acceleration techniques for the method of characteristics (MOC) in the code APOLLO-2. The main contribution concerns the introduction of a multidomain DPN technique where all regions belonging to the same macrodomain are coupled by an integral operator that is strictly equivalent to the MOC. Different macrodomains are coupled via currents that are defined with the DPN formalism. This new integral DPN(IDPN) operator is built by using transmission and escape probability factors that respect symmetries/antisymmetries and complementary properties that are enforced to preserve the physics of the problem and to save computational effort. These factors are computed using the numerical tracking of the MOC operator. This paper presents results on realistic assembly calculations that demonstrate the effectiveness of the IDPN operator as a synthetic acceleration tool.
