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Division Spotlight
Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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Latest News
NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
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.
