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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Tawfik A. Al-Kusayer
Nuclear Technology | Volume 69 | Number 3 | June 1985 | Pages 293-307
Technical Paper | Nuclear Safety | doi.org/10.13182/NT85-A33612
Articles are hosted by Taylor and Francis Online.
The availability of the emergency core cooling system (ECCS) as a long-term safety backup system following a small loss-of-coolant accident (LOCA) has been analyzed for the Pickering NGS Unit A, a Canada deuterium uranium (CANDU) type of pressurized heavy-water reactor (PHWR). Fault tree analysis methodology was used to assess the unavailability of the ECCS. The PREP and KITT computer codes were used to estimate the failure probabilities. From these computations, the unavailability of the ECCS to supply sufficient coolant to the core is estimated as 3.63 × 10−3. This figure is higher than the failure probability target 3 × 10−3 that is specified by the Canadian Atomic Energy Control Board for the safety systems of CANDU PHWRs. It has been found that human error might make a very important contribution to ECCS unavailability, especially if the human error rates have been assigned the upper bound values in the fault tree calculations. That should be the case, therefore, for any fault analysis and reliability assessment of nuclear generating stations. Unlike the case for light water reactors, the ECCS in a CANDU PHWR is not the last defense against the LOCA, because of the availability of quite a large amount of D2O moderator in the calandria around the pressure tubes.
