arXiv subjects

Jozef Kováč

Publications and source records attributed to Jozef Kováč.

4 recordsLinked to original sources

arXiv2018

Distributional Chaos in Random Dynamical Systems

In this paper, we introduce the notion of distributional chaos and the measure of chaos for random dynamical systems generated by two interval maps. We give some sufficient conditions for a zero measure of chaos and examples of chaotic systems. We demonstrate that the chaoticity of the functions that generate a system does not, in general, affect the chaoticity of the system, i.e., a chaotic system can arise from two nonchaotic functions and vice versa. Finally, we show that distributional chaos for random dynamical system is, in some sense, unstable.

math.DS↗

arXiv2017

Random dynamical systems generated by two Allee maps

In this paper, we study random dynamical systems generated by two Allee maps. Two models are considered - with and without small random perturbations. It is shown that the behavior of the systems is very similar to the behavior of the deterministic system if we use strictly increasing Allee maps. However, in the case of unimodal Allee maps, the behavior can dramatically change irrespective of the initial conditions.

math.DS↗

arXiv2017

Structural characterization of magnetoferritin

The physicochemical characterization of the magnetoferritin biomacromolecule in terms of morphology, structural and magnetic properties shows that iron oxides can be efficiently loaded into apoferritin molecules, preserving their native biocompatible structure and affecting the morphology of the protein shell.

cond-mat.mtrl-sci↗

arXiv2014

Magnetoresistance of composites based on graphitic disks and cones

We have studied the magnetotransport of conical and disk-shaped nanocarbon particles in magnetic fields $\left|B\right|\leq9\:\mathrm{T}$ at temperatures $2\leq T\leq300\:\mathrm{K}$ to characterize electron scattering in a three dimensional disordered material of multilayered quasi 2D and 3D carbon nanoparticles. The microstructure of the particles was modified by graphitization at temperatures $1600^{\circ}\mathrm{C}$ and $2700^{\circ}\mathrm{C}$. We find clear correlations between the microstructure as seen in transmission electron microscopy and the magnetotransport properties of the particles. The magnetoresistance measurements showed a metallic nature of samples and positive magnetoconductance which is a signature of weak localization in disordered systems. We find that the magnetoconductance at low temperatures resembles quantum transport in single-layer graphene despite the fact that the samples are macroscopic and three dimensional, consisting of stacked and layered particles, which are randomly oriented in the bulk sample. This graphene-like behaviour is attributed to the very weak interlayer coupling between the graphene layers.

cond-mat.mes-hall↗