Limited data are available to describe the regulation of heart rate (HR) during sleep in spaceflight. Sleep provides a stable supine baseline during preflight Earth recordings for comparison of heart rate variability (HRV) over a wide range of frequencies using both linear, complexity, and fractal indicators. The current study investigated the effect of long-duration spaceflight on HR and HRV d...

In has been known to antenna engineers that periodic arrays can be used to effectively suppress radiation pattern side-lobes with just a small number of elements but are more susceptible to effects from element failure. Random arrays on the other hand are more robust in terms of element failure but are not typically able to suppress side-lobe levels as effectively as their periodic counterparts...

Major aim of this study is to define the copper and gold anomalies using the combination of the Concentration-Number (C-N) fractal and the stepwise factor analysis, based on stream sediment samples in Lahrud 1:100,000 sheet, NW Iran. The case study is situated in Alborz-Azerbaijan structural zone. Elements related to Au and Cu hydrothermally mineralization were selected for this study, accordin...

This paper demonstrates that the absorption and scattering cross-sections and the asymmetry factor of randomly oriented fractal aggregates of spherical monomers can be rapidly estimated as those of coated spheres with equivalent volume and average projected area. This was established for fractal aggregates with fractal dimension ranging from 2.0 to 3.0 and composed of up to 1000 monodisperse or...

The Invariant Set Hypothesis proposes that states of physical reality belong to, and are governed by, a non-computable fractal subset I of state space, invariant under the action of some subordinate deterministic causal dynamics I D . The Invariant Set Hypothesis is motivated by key results in nonlinear dynamicalsystems theory, and black-hole thermodynamics. The elements of a reformulation of q...