Time evolving clustering of the low-frequency magnetic field radiation emitted from laptop computers

The study presents a new time evolving clustering method for tracing the evolution of magnetic field ranges emitted from laptops over time. It is an extension of K-Medians algorithm for which cluster set found at current time point depends not only on the current measured values but also on the cluster sets found at the previous time points. The method is employed on the measured magnetic field radiation of the laptops in the extremely low frequency range at multiple frequencies of TCO standard. Specifically, a new measurement methodology of the magnetic field to which the users of the laptop are exposed in the office environment is proposed. The level of the magnetic field variation in time is measured. Results show that method can be employed to detect the most dangerous magnetic field ranges in laptop areas. Also, it is usable by manufacturers for advancing the safe laptop design or by laptop users for safer and more appropriate use.