Chakraverty S, Sahoo B K, Rao T D, Karunakar P, Sapra B K
Department of Mathematics, National Institute of Technology Rourkela, Odisha, 769008, India.
Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Mumbai, 400 094, India.
J Environ Radioact. 2018 Feb;182:165-171. doi: 10.1016/j.jenvrad.2017.12.007. Epub 2017 Dec 16.
Modelling radon transport in the earth crust is a useful tool to investigate the changes in the geo-physical processes prior to earthquake event. Radon transport is modeled generally through the deterministic advection-diffusion equation. However, in order to determine the magnitudes of parameters governing these processes from experimental measurements, it is necessary to investigate the role of uncertainties in these parameters. Present paper investigates this aspect by combining the concept of interval uncertainties in transport parameters such as soil diffusivity, advection velocity etc, occurring in the radon transport equation as applied to soil matrix. The predictions made with interval arithmetic have been compared and discussed with the results of classical deterministic model. The practical applicability of the model is demonstrated through a case study involving radon flux measurements at the soil surface with an accumulator deployed in steady-state mode. It is possible to detect the presence of very low levels of advection processes by applying uncertainty bounds on the variations in the observed concentration data in the accumulator. The results are further discussed.
模拟地壳中的氡运移是研究地震事件前地球物理过程变化的一种有用工具。氡运移通常通过确定性平流扩散方程进行模拟。然而，为了从实验测量中确定控制这些过程的参数大小，有必要研究这些参数不确定性的作用。本文通过结合应用于土壤基质的氡运移方程中出现的传输参数（如土壤扩散率、平流速度等）的区间不确定性概念来研究这一方面。用区间算法做出的预测已与经典确定性模型的结果进行了比较和讨论。通过一个案例研究证明了该模型的实际适用性，该案例涉及使用以稳态模式部署的累积器在土壤表面进行氡通量测量。通过对累积器中观测浓度数据变化应用不确定性界限，有可能检测到极低水平的平流过程的存在。对结果进行了进一步讨论。
