ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference 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!
Latest Magazine Issues
Aug 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
August 2025
Fusion Science and Technology
Latest News
Ho Nieh nominated to the NRC
Nieh
President Trump recently nominated Ho Nieh for the role of commissioner in the Nuclear Regulatory Commission through the remainder of a term that will expire June 30, 2029.
Nieh has been the vice president of regulatory affairs at Southern Nuclear since 2021, though he is currently working as a loaned executive at the Institute of Nuclear Power Operations, where he has been for more than a year.
Nieh’s experience: Nieh started his career at the Knolls Atomic Power Laboratory, where he worked primarily as a nuclear plant engineer and contributed as a civilian instructor in the U.S. Navy’s Nuclear Power Program.
From there, he joined the NRC in 1997 as a project engineer. In more than 19 years of service at the organization, he served in a variety of key leadership roles, including division director of Reactor Projects, division director of Inspection and Regional Support, and director of the Office of Nuclear Reactor Regulation.
K. Behringer, G. Kosály, I. Pázsit
Nuclear Science and Engineering | Volume 72 | Number 3 | December 1979 | Pages 304-321
Technical Paper | doi.org/10.13182/NSE79-A20387
Articles are hosted by Taylor and Francis Online.
According to recent investigations, the neutron noise field in a boiling water reactor can be separated into a local and a global component. In the present paper, these two components are discussed further via two-group diffusion theory. The expediency of the local-global concept is compared to another concept based on separating components corresponding to the two roots of the dynamic eigenvalue problem. The mathematical discussion of the neutron response to a propagating perturbation of the moderator density is given. Point reactor behavior and “linear-phase behavior” appear as two extremes of the neutron response. The mathematical results are illustrated numerically for the cases of a large power reactor core and a small highly enriched core.