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.
Division Spotlight
Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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!
Latest Magazine Issues
Jan 2025
Jul 2024
Latest Journal Issues
Nuclear Science and Engineering
February 2025
Nuclear Technology
Fusion Science and Technology
Latest News
IEA report: Challenges need to be resolved to support global nuclear energy growth
The International Energy Agency published a new report this month outlining how continued innovation, government support, and new business models can unleash nuclear power expansion worldwide.
The Path to a New Era for Nuclear Energy report “reviews the status of nuclear energy around the world and explores risks related to policies, construction, and financing.”
Find the full report at IEA.org.
Keisuke Kobayashi
Nuclear Science and Engineering | Volume 31 | Number 1 | January 1968 | Pages 91-101
Technical Paper | doi.org/10.13182/NSE68-A18011
Articles are hosted by Taylor and Francis Online.
The group diffusion equations in two dimensions are solved by assuming the separation of variables sectionally. Using one-dimensional Green's functions, the two-dimensional diffusion equations are transformed into two sets of one-dimensional three-point difference equations at fine-mesh points. Assuming that the separation of variables of x and y coordinates is possible in a coarse mesh in a reactor, the two sets of one-dimensional difference equations are solved by the alternating direction iteration method. Sample calculations for 235U-H2O thermal reactors show that this method gives fairly good results with few coarse and fine meshes and the computation time can be considerably reduced compared with the usual finite difference method.