We address the problem of Blind Source Separation (BSS) in the context of instantaneous (memoryless) linear mixtures, where the unknown mixing coefficients are time varying, changing periodically in time. Such a mixing model is realistic, e.g., when considering a biological or physiological system where the mixing coefficients are affected by periodic processes like breathing, heart-beating etc...

This paper presents a low complexity architecture for a linear periodically time varying (LPTV) filter. This architecture is based on multi-input multi-output(MIMO) representation of LPTV filters. The input signal is divided into blocks and parallel processing is incorporated, there by considerably reducing the effective input sampling rate. A single multiplier can be shared for each linear tim...

Using continued fractions we study the ground state properties of the spin– 1 2 Ising chain in a transverse field with periodically varying interaction strengths and external fields. We consider in detail the chain having the period of modulation of interactions equals 2 and compare the results obtained with those corresponding to the spin– 1 2 isotropic XY chain in a transverse field. In contr...

We study solute dispersion in channels with periodically varying apertures. Based on an approximate analytical solution of the flow equation, we study the impact of the geometry and molecular diffusion on effective solute dispersion analytically using the method of local moments. We also study the problem numerically using a random walk particle tracking method. For transport in parallel shear ...

Wildland firefighters work in unfavourable environments involving both heat and moisture. Moisture in clothing systems worn by wildland firefighters may increase or decrease heat transfer, depending on its source and location in the clothing system, location on the body, timing of application and degree of sorption. In this experiment, 4 outerwear/underwear combinations were exposed to 1 of 5 d...

Stimulated by a general necessary and sufficient condition for robust stability of sampled-data systems stated in an operator-theoretic framework, we introduce a novel technique called linear periodically timevarying (LPTV) scaling. We then give a simple example of sampled-data systems in which this new scaling allows exact robust stability analysis for static uncertainties while the convention...