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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
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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Oak Ridge community roundtable explores workforce challenges
Federal and contractor officials, community leaders, and educators gathered in Knoxville, Tenn., on October 29 for a roundtable event focused on ensuring the Oak Ridge Office of Environmental Management (OREM) and its partners have the resources and infrastructure needed to support a robust, talented workforce in the years ahead.
Syed Hameed Qaiser, Masood Iqbal, Aamer Iqbal Bhatti, Raza Samar, Javed Qadir
Nuclear Science and Engineering | Volume 172 | Number 3 | November 2012 | Pages 327-336
Technical Paper | doi.org/10.13182/NSE11-46
Articles are hosted by Taylor and Francis Online.
This paper discusses a higher-order sliding-mode-observer design for estimating reactivity in a nuclear research reactor. The nonlinear model of the Pakistan Research Reactor-1 (PARR-1) has been tuned and validated with experimental data. This model is then used for higher-order sliding-mode-observer-based reactivity estimation. In thermal reactors, reactivity is a very important reactor variable, as it determines the change of output power variation and is the main variable being manipulated for reactor power control. Linear observers have been used in the past to estimate reactivity, but the bandwidth is limited, and performance gets degraded as the operating point is changed. A nonlinear observer can efficiently address this problem. In this paper a robust higher-order sliding-mode observer is employed to estimate this variable. The higher-order sliding-mode observer is efficient and has the main advantage of reduced chattering. The estimators predict this variable with the measurement of neutron flux only. The estimated value is in close agreement with the theoretically calculated value.