Efficient Computation of Radioactive Decay with Graph Algorithms

• Published in: Journal of nuclear fuel cycle and waste technology (Online) Vol. 18; no. 1; pp. 19 - 29
• Main Author: Yoo, Tae-Sic
• Format: Journal Article
• Language: Korean
• Published: 한국방사성폐기물학회 30.03.2020; Korean Radioactive Waste Society
• Subjects: Nuclear fuel cycle; Radioactive decay computation; Graph algorithms
• ISSN: 1738-1894; 2288-5471

This paper gives two graph-based algorithms for radioactive decay computation. The first algorithm identifies the connected components of the graph induced from the given radioactive decay dynamics to reduce the size of the problem. The solutions are derived over the precalculated connected components, respectively and independently. The second algorithm utilizes acyclic structure of radioactive decay dynamics. The algorithm evaluates the reachable vertices of the induced system graph from the initially activated vertices and finds the minimal set of starting vertices populating the entire reachable vertices. Then, the decay calculations are performed over the reachable vertices from the identified minimal starting vertices, respectively, with the partitioned initial value over the reachable vertices. Formal arguments are given to show that the proposed graph inspired divide and conquer calculation methods perform the intended radioactive decay calculation. Empirical efforts comparing the proposed radioactive decay calculation algorithms are presented.