This letter addresses the problem of fetal electrocardiogram (FECG) extraction. A class of source extraction algorithms is proposed, which uses a combination of two different approaches: Barros’s source extraction approach and Hyvärinen’s fixedpoint approach. The proposed algorithms can rapidly extract the desired FECG with little noise, and can work well in some bad situations. The validity an...

This paper is devoted to the study of the following nonlocal p -Laplacian functional differential equation −φp(x′(t)) )′ = λ f (t,x(t),x ′ (t)) (∫ 1 0 f (s,x(s),x′ (s))ds )n , 0 < t < 1, subject to multi point boundary conditions. We obtain some results on the existence of at least one (when n ∈ Z+ ) or triple (when n = 0) pseudo-symmetric positive solutions by using fixedpoint theory in cone. ...

Within the framework of exact renormalization group flow equations, a scale-dependent transformation of the field variables provides for a continuous translation of UV to IR degrees of freedom. Using the gauged NJL model as an example, this translation results in a construction of partial bosonization at all scales. A fixedpoint structure arises which makes it possible to distinguish between fu...

Digital linear filters are used in a variety of applications (sound treatment, control/command, etc.), implemented in software, in hardware, or a combination thereof. For safety-critical applications, it is necessary to bound all variables and outputs of all filters. We give a compositional, effective abstraction for digital linear filters expressed as block diagrams, yielding sound, precise bo...

Taking Löb's Axiom in modal provability logic as a running thread, we discuss some general methods for extending modal frame correspondences, mainly by adding fixedpoint operators to modal languages as well as their correspondence languages. Our suggestions are backed up by some new results – while we also refer to relevant work by earlier authors . But our main aim is advertizing the perspecti...

In this paper we prove a unique common coupled fixed point theorem for two pairs of $w$-compatible mappings in $S_b$-metric spaces satisfying a contrctive type condition. We furnish an example to support our main theorem. We also give a corollary for Junck type maps.