Fractal behavior and long-range dependence have been observed in an astonishing number of physical, biological, geological, and socio-economic systems. Time series, profiles, and surfaces have been characterized by their fractal dimension, a measure of roughness, and by the Hurst coefficient, a measure of long-memory dependence. Either phenomenon has been modeled and explained by self-affine ra...

By means of the concepts of factorial moment, return map and NM estimator, we analyze some responses of a HH neuron to various types of spike-train inputs. The corresponding fractal dimensions and values of NM estimators can describe the correlation characteristics quantitatively. It is found that all the intervals of successive output spikes may obey a power-law for some conditions. And in tim...

Fossil extinction power spectra, recently published by Dimri and Prakash [1], appear to exhibit power-law scaling in which spectral power is inversely proportional to frequency. Dimri and Prakash interpret their results as demonstrating a fractal pattern in the fossil record, with longrange correlations that suggest self-organized critical dynamics. Here I point out that their methods are vulne...

We consider the cluster mass distribution between two lines of arbitrary orientations and lengths in porous media in three dimensions, and model the porous media by bond percolation at the percolation threshold pc. We observe that for many geometrical con.gurations the mass probability distribution presents power law behavior. We determine how the characteristic mass of the distribution scales ...

The traditional methods of analysing heart rate variability based on means and variance are unable to detect subtle but potentially important changes in interbeat heart rate behaviour. This research was designed to evaluate the clinical applicability and prognostic significance of new dynamical methods of analysing heart rate behaviour derived from nonlinear mathematics. The study covered four ...

[1] We measured the hyporheic residence time distribution in a 2nd-order mountain stream at the H. J. Andrews Experimental Forest, Oregon, and found it to be a power-law over at least 1.5 orders of magnitude in time (1.5 hr to 3.5 d). The residence time distribution has a very long tail which scales as t , and is poorly characterized by an exponential model. Because of the small power-law expon...

Much is known regarding the structure and logic of genetic regulatory networks. Less understood is the contextual organization of promoter signals used during transcription initiation, the most pivotal stage during gene expression. Here we show that promoter networks organize spontaneously at a dimension between the 1-dimension of the DNA and 3-dimension of the cell. Network methods were used t...

A social network often has numerous interesting attributes. When an attribute is quantified, a social tomography would arise from the underlying social network. One of the most interesting attributes is crime hotspots, whose existence has been strongly supported by observations that serious crimes ranging from residential burglary to homicide are strongly patterned in time and space, and by mat...

introduction: soil hydraulic conductivity is considered as one of the most important hydraulic properties in water and solutionmovement in porous media. in recent years, variousmodels as pedo-transfer functions, fractal models and scaling technique are used to estimate the soil saturated hydraulic conductivity (ks). fractal models with two subset of two (solid and pore) and three phases (solid,...

One of the main bene...ts of multicast communication is the overall reduction of network load. To quantify this reduction, when compared to traditional unicast, experimental studies by Chuang and Sirbu indicated the so called power law which asserts that the number of links L(m) in a multicast delivery tree connecting a source to m (distinct) sites satis...es L(m) 1⁄4 cm where c is a constant. ...