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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
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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Dragonfly, a Pu-fueled drone heading to Titan, gets key NASA approval
Curiosity landed on Mars sporting a radioisotope thermoelectric generator (RTG) in 2012, and a second NASA rover, Perseverance, landed in 2021. Both are still rolling across the red planet in the name of science. Another exploratory craft with a similar plutonium-238–fueled RTG but a very different mission—to fly between multiple test sites on Titan, Saturn’s largest moon—recently got one step closer to deployment.
On April 25, NASA and the Johns Hopkins University Applied Physics Laboratory (APL) announced that the Dragonfly mission to Saturn’s icy moon passed its critical design review. “Passing this mission milestone means that Dragonfly’s mission design, fabrication, integration, and test plans are all approved, and the mission can now turn its attention to the construction of the spacecraft itself,” according to NASA.
Ho Seok, Hee Cheon No, Sung Jae Cho, Sang Doug Park, Hwang Young Jun, Yong Kwan Lee
Nuclear Technology | Volume 106 | Number 3 | June 1994 | Pages 384-396
Technical Paper | Reactor Operation | doi.org/10.13182/NT94-A34968
Articles are hosted by Taylor and Francis Online.
A workstation-based real-time simulator for two-loop pressurized water reactor plants is developed for classroom training in support of a full-scale simulator, on-site transient analysis, and engineering studies. The present simulator consists of three functional modules: plant module, graphic module, and man-machine interaction module. The plant module includes models for the core kinetics, reactor coolant system, steam generator, main steam line, balance of plant, and control and protection system. Each of the models is optimized to obtain the capability of real-time simulation. For simulating the thermal-hydraulic behavior of the reactor coolant system in the plant module, a fully-implicit safety analysis-2/workstation (FISA-2 /WS) is developed, which adopts implicit algorithms for their inherent stability and efficiency in solving the stiff set of equations that resulted from component models. It allows the use of a larger time step than the Courant limit without any numerical instability, and it also guarantees reasonable accuracy. And the level tracking logic and the peak cladding temperature calculation model on the basis of the simple analytical model are used to track the two-phase water level in the core and to predict the cladding temperature in the uncovered region of the core under accidents, respectively. The graphic module is designed to provide the user with more information at a glance by dynamically displaying schematic diagrams of the systems, symbols indicating the operating status of each component, trend curves, and the main control room. Especially, the CONTROL ROOM menu is designed to enable the user to perform his specific actions through the schematic diagrams of the main control panels in a way similar to which operators do them in the main control room for the KO-RI Nuclear Power Plant Unit 2. In each schematic diagram of five sections, the indicators and alarms display the various operating parameters, alarm signals, and trip signals, and the user can control the various components by operating the corresponding switches in each section through the mouse. Also, the user can initiate his actions through various system diagrams. As tools for the man-machine interface, the man-machine interaction model uses a color cathode ray tube monitor, a standard keyboard, and the mouse. The interactive communication module receives parameters from the user via the keyboard and mouse, and transfers them to the plant module so as to enable the user to perform his specific actions. This module provides the user with various initiating events (malfunctions and manual controls) through SYSTEM, CONTROL ROOM, and ACCIDENTS menus, and thus a wide range of nuclear steam supply system transients can be easily simulated. This module also enables the user to select one of the menu-driven graphic displays. The FISA-2/WS is verified through comparisons with analytical solutions, separated tests and integral tests, and predictions by RETRAN-2 and RELAP5/MOD3. Through the various tests of FISA-2/WS, it is convincing that FISA-2/WS can simulate most transients of the KO-RI Unit 2 with reasonable accuracy in real time.
