arXiv subjects

Baruch Vainas

Publications and source records attributed to Baruch Vainas.

3 recordsLinked to original sources

arXiv2016

Nearly constant loss - the 2nd universality of AC conductivity by scaling down subsequent random walk steps by 1/t^(1/2)

In the frequency domain, the nearly constant loss, is characterized by a slope 1 in log of the real part of the electrical conductivity vs log frequency plots. It can be explained by an anomalous diffusion, defined by a random walk with the mean square displacement proportional to the logarithm of time, rather than being linearly proportional to time, as in normal diffusion. The present work suggests a random walk algorithm that leads to anomalous, logarithmic time dependence. That has been accomplished by scaling down the subsequent random walk displacements by a factor, 1/t^(1/2)

cond-mat.stat-mech↗

arXiv2008

Transition from 12 to near-24 hours glucose circadian rhythm on relaxation of a hyperglycemic condition

A composite, exponential relaxation function, modulated by a periodic component, was used to fit to an experimental time series of blood glucose levels. The 11 parameters function that allows for the detection of a possible rhythm transition was fitted to the experimental time series using a genetic algorithm. It has been found that the relaxation from a hyperglycemic condition following a change in the anti-diabetic treatment, can be characterized by a change from an initial 12 hours ultradian rhythm to a near-24 hours circadian rhythm.

q-bio.QM↗

arXiv2005

Modelling the 0.6 - 0.7 power law of permittivity and admittance frequency responses in random R-C networks

The dielectric response of complex materials is characterized, in many cases, by a similar power law frequency dependence of both the real and the imaginary parts of their complex dielectric constants. In the admittance representation, this power law is often shown as the constant phase angle (CPA) response. Apparently, the power that characterizes many different systems, when expressed as the frequency dispersion of conductivity (the real part of admittance) is often found to be in the range of 0.6 - 0.7 or having frequency independent, constant phase angles (CPA) of about 54 - 63 deg. The model suggested here is based on series-parallel mixing of resistors' and capacitors' responses in a random R-C network. A geometric mean evaluation of the effective resistivity of conductors having a uniform distribution of resistivity is used. In contrast to models based on percolation arguments, the model suggested here can be applied to both 2D and 3D systems.

cond-mat.mtrl-sci↗