High-resolution measurements of pulmonary perfusion reveal substantial spatial heterogeneity that is fractally distributed. This observation led to the hypothesis that the vascular tree is the principal determinant of regional blood flow. Recent studies using aerosol deposition show similar ventilation heterogeneity that is closely correlated with perfusion. We hypothesize that ventilation has ...

– We study the (newtonian) gravitational force distribution arising from a fractal set of sources. We show that, in the case of real structures in finite samples, an important role is played by morphological properties and finite size effects. For dimensions smaller than d − 1 (being d the space dimension) the convergence of the net gravitational force is assured by the fast decaying of the den...

This paper studies the effect of the distance choice in radial (non-average) statistical tools used for fractal characterization of the galaxy distribution. After reviewing the basics of measuring distances of cosmological sources, various distance definitions are used to calculate the differential density γ and the integral differential density γ∗ of the dust distribution in the Einstein-de Si...

introduction nowadays, many studies were performed about noise source and its type and effects related to duration of sound emission. most of these researches just report sound pressure level in frequency or time domain. these researches should be continued in order to find better absorber material in noise pollution. use of fractal geometry is a new method in this filed. wave fractal dimension...

On the one hand, the large scale structure of matter is arguably scale invariant, and, on the other hand, halos and voids are recognized as prominent features of that structure. To unify both approaches, we propose to model the dark matter distribution as a set of fractal distributions of halos of different kinds. This model relies on the concept of multifractal as the most general scaling dist...

In contrast to the conventional wisdom that scale-free networks are prone to epidemic propagation, in the paper we present that disease spreading is inhibited in fractal scale-free networks. We first propose a novel network model and show that it simultaneously has the following rich topological properties: scale-free degree distribution, tunable clustering coefficient, “large-world” behavior, ...

Conserved non-coding elements (CNEs) are defined using various degrees of sequence identity and thresholds of minimal length. Their conservation frequently exceeds the one observed for protein-coding sequences. We explored the chromosomal distribution of different classes of CNEs in the human genome. We employed two methodologies: the scaling of block entropy and box-counting, with the aim to a...

We present a review of the history and the present state of the fractal approach to the large-scale distribution of galaxies. The roots of the modern idea of cosmic fractality go to the beginning of the 20th century, when hierarchical world models were proposed by Fournier and Charlier. Fundamental aspects of hierarchical matter distribution was discussed by Einstein and Selety in the correspon...

In this paper we review some recent results concerning the approximations of distribution functions and measures on [0, 1] based on iterated function systems. The two different approaches available in the literature are considered and their relation are investigated in the statistical perspective. In the second part of the paper we propose a new class of estimators for the distribution function...

This comment is in response to the paper by L. Guzzo recently appeared in “New Astronomy” related to our work. The subject of the discussion concerns the correlation properties of galaxy distribution in the available 3-d samples. There is a general agreement that galaxy structures exhibit fractal properties, at least up to some scale. However the presence of an eventual crossover towards homoge...