[1J01-10] Dose Management

[1J10] Anthropogenic impacts on temporal decrease in air dose rate in urban areas

(3) Correlation between population dynamics and ecological half-life decay estimated by using LASSO

*Masahiko Machida¹, Uno Shumpei², Naoki Tanimura², Kimiaki Saito¹, Kazuya Yoshimura¹ (1. Japan Atomic Energy Agency, 2. Mizuho Research & Technologies)

Keywords:Fukushima Daiichi Nuclear Power Plants, Urban Area, Air Dose Rates, Ecologilcal half life, Population Dynamics, LASSO

Air dose rates in urban areas decrease faster in residential areas than in evacuation zones. This suggests that human activities facilitate the reduction. However, since human activities include various factors such as decontamination and road wear caused by traffic, it is difficult to evaluate the effect of human activities by conventional analysis using monitoring data, except for the effect of decontamination. Then, this series of studies aim to evaluate the effects of human activities on the reduction. Among the series presentations, this one
focuses on correlations between population dynamics characterized by mobile phone GPS information and ecological half life decays of air dose rates measured by KURAMA over a wide area with long-term monitoring using
LASSO scheme.