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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
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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
Bipartisan Nuclear REFUEL Act introduced in the U.S. House
Peters
Latta
To streamline the licensing requirements for nuclear fuel recycling facilities and help increase investment in nuclear energy in the United States, U.S. Reps. Bob Latta (R., Ohio) and Scott Peters (D., Calif.) have introduced the bipartisan Nuclear REFUEL Act in the House of Representatives.
The bill, introduced on December 6, would amend the definition of “production facility” in the Atomic Energy Act, clarifying that a reprocessing facility producing uranium-transuranic mixed fuel would be licensed only under 10 CFR Part 70. According to the lawmakers, this single-step licensing process would significantly streamline the licensing requirements for fuel recycling facilities.
Jeffrey A. Favorite, Zoltán Perkó, Brian C. Kiedrowski, Christopher M. Perfetti
Nuclear Science and Engineering | Volume 185 | Number 3 | March 2017 | Pages 384-405
Technical Paper | doi.org/10.1080/00295639.2016.1272990
Articles are hosted by Taylor and Francis Online.
The evaluation of uncertainties is essential for criticality safety. This paper deals with material density and composition uncertainties and provides guidance on how traditional first-order sensitivity methods can be used to predict their effects. Unlike problems that deal with traditional cross-section uncertainty analysis, material density and composition-related problems are often characterized by constraints that do not allow arbitrary and independent variations of the input parameters. Their proper handling requires constrained sensitivities that take into account the interdependence of the inputs. This paper discusses how traditional unconstrained isotopic density sensitivities can be calculated using the adjoint sensitivity capabilities of the popular Monte Carlo codes MCNP6 and SCALE 6.2, and we also present the equations to be used when forward and adjoint flux distributions are available. Subsequently, we show how the constrained sensitivities can be computed using the unconstrained (adjoint-based) sensitivities as well as by applying central differences directly. Three distinct procedures are presented for enforcing the constraint on the input variables, each leading to different constrained sensitivities. As a guide, the sensitivity and uncertainty formulas for several frequently encountered specific cases involving densities and compositions are given. An analytic k∞ example highlights the relationship between constrained sensitivity formulas and central differences, and a more realistic numerical problem reveals similarities among the computer codes used and differences among the three methods of enforcing the constraint.