UMR peak algorithm data manipulation phases over the day 143 in Ringebu stave church: (a) original time series of MRin1 (yellow curve), MRin2 (red curve) and MRout (green curve); (b) smoothed time series of MRin (orange) and MRout (green); (c) time series first derivatives: derMRin (orange), derMRout (green) and visual definition of feature Delta