Abstract: Method and device for extracting noise-reduced signal information from a time series of sensor measurements during normal process operation and then actively checking whether present realizations of the process are departing from historical normal behavior. To extract signal information, the solution borrows ideas from singular spectrum analysis a non-parametric exploratory analysis tool for time series that is particularly suitable for separating the deterministic part of a dynamical system behavior from the chaotic part, purely from noisy time series of measurements.