We introduce a new, physical-space-based method for deriving the precise leading-order late-time behaviour of solutions to geometric wave equations on asymptotically flat spacetime backgrounds and apply it setting with inverse-square potentials Schwarzschild black holes. This provides useful toy model introducing methods that are applicable more general linear nonlinear equations, such as elect...

An 'instantaneous' optimal filter is presented for improving the signal-to-noise ratio in averaged electrocardiograms (ECGs). The filter design is based on a simple model that accounts for correlation across the ensemble of beats but ignores correlation in time. Another property of the model is that the noise level is allowed to change from beat to beat. Simulation results indicate that an impr...

Late ventricular potentials (LVPs) are low amplitude, high frequency waveforms, appearing in the terminal part of the QRS complex of the electrocardiogram (Barbosa et al, 2002; Olinic & Zdrenghea, 1998), generated by diseased myocardium. They may extend in the ST segment (Zimmermann et al, 1983). Late ventricular potentials may be also defined as fragmented electrical activity, appearing in het...