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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott 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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Latest News
BREAKING NEWS: Trump issues executive orders to overhaul nuclear industry
The Trump administration issued four executive orders today aimed at boosting domestic nuclear deployment ahead of significant growth in projected energy demand in the coming decades.
During a live signing in the Oval Office, President Donald Trump called nuclear “a hot industry,” adding, “It’s a brilliant industry. [But] you’ve got to do it right. It’s become very safe and environmental.”
Vikas Pandey, Suneet Singh
Nuclear Science and Engineering | Volume 188 | Number 2 | November 2017 | Pages 187-197
Technical Paper | doi.org/10.1080/00295639.2017.1350003
Articles are hosted by Taylor and Francis Online.
The nonlinear stability analysis of an advanced heavy water reactor (AHWR) is performed to investigate global stability. The global stability perspective predicts the exact stability boundary of the system, which is valid for small as well as large disturbances in the system. Recently, the local or linear stability boundary and bifurcation of limit cycles has been discussed for an AHWR. However, the studies were not sufficient to predict global stability of the system. In this work, advanced bifurcation analysis is carried out for an AHWR, which unfolds multistable or unstable states. The region of multistability is observed due to the presence of steady states and multiple limit cycles. The global stability boundary is marginally away from the local stability boundary, the region beyond which the global stability boundary is safe for operation due to the nonexistence of nonlinear phenomena, such as limit cycles. The local stability boundary is basically a Hopf bifurcation boundary as limit cycles (i.e., nonlinear phenomena) emerge from these points. Subcritical or supercritical Hopf bifurcations excite unstable limit cycles (ULCs) or stable limit cycles (SLCs), respectively, and these limit cycles end on the global stability boundary. The subcritical Hopf bifurcation is considered as hard or dangerous bifurcation due to the presence of ULCs in the linearly stable region, which gains stability on the global stability boundary and in which SLCs surround ULCs. Therefore, a region of bistability between the local and global stability boundary is present for subcritical Hopf. The supercritical Hopf is generally considered as the soft and safe bifurcation because of SLCs in the linearly unstable region. Due to this fact, it is assumed that in the supercritical Hopf region the global and local stability boundaries are the same. However, in this work ULCs in the linearly stable region for supercritical Hopf bifurcation are observed along with SLCs, which is an uncommon phenomenon in nuclear reactors. The presence of ULCs surrounding SLCs are observed both in the stable and unstable side on the parameter plane for supercritical Hopf. For the safe operation of a nuclear reactor, identification of the region of global stability is of paramount interest.