Aim of this note is to give a simple and direct proof of the existence and uniqueness of the solution to the problem of electrostatics when the source (namely, the applied current density) is a dipole. The result is obtained by using the classical duality method.

We study the problem of entropy increase of the Bernoulli-shift map without recourse to the concept of trajectory and we discuss whether, and under which conditions if it does, the distribution density entropy coincides with the Kolmogorov-Sinai entropy, namely, with the trajectory entropy. 05.45.+b,03.65.Sq,05.20.-y Typeset using REVTEX 1

We computationally compare four procedures, namely, alpha-shapes, iso-surface extraction, gridfit and L1 splines for geometric reconstruction of 3D urban structures represented by irregular point clouds with abrupt changes in density. For significant numbers of outliers, L1 splines produce the most accurate reconstructions both visually and when measured analytically in the Hausdorff metric but...

By incorporating lightweight expanded polystyrene aggregate particles in a conventional highstrength concrete mixture, its density could be adjusted to any desired level. The adjusted density concrete can be expected to have reduced strength and stiffness the permeability of concrete would not be affected since the non-water absorbing polystyrene aggregate particles are dispersed randomly in a ...

The potential of recycled waste polymeric materials as a substitute for aggregates in concrete has been investigated in the study. Two different types of waste polymer, namely polyurethane formaldehyde (PUF) based packaging waste and high density polyethylene (HDPE) were recycled and used in the experiment. Concrete and masonry poly block specimens were prepared using recycled polymer materials...

We expand on a previous study of fronts in finite particle number reaction-diffusion systems in the presence of a reaction rate gradient in the direction of the front motion. We study the system via reaction-diffusion equations, using the expedient of a cutoff in the reaction rate below some critical density to capture the essential role of fluctuations in the system. For large density, the vel...

We consider the problem of constructing dense lattices of Rn with a given non trivial automorphism group. We exhibit a family of such lattices of density at least cn2−n, which matches, up to a multiplicative constant, the best known density of a lattice packing. For an infinite sequence of dimensions n, we exhibit a finite set of lattices that come with an automorphism group of size n, and a co...

this article introduces a new tri-parameter law of corresponding states from the known regularities, namely the lir and zeno line for dense fluids (when tz=tc). two of these parameters are the zeno line parameters and the third parameter (the fluid parameter), has been obtained from the lir, this parameter is solely dependent upon the fluid characteristics. the third parameter can be obtaind fr...

Recently, an analytic method was developed to study in the large N limit nonHermitian random matrices that are drawn from a large class of circularly symmetric non-Gaussian probability distributions, thus extending the existing Gaussian non-Hermitian literature. One obtains an explicit algebraic equation for the integrated density of eigenvalues from which the Green’s function and averaged dens...

Experiments have shown that pollen tubes grow in an oscillatory mode, the mechanism of which is poorly understood. We propose a theoretical growth model of pollen tubes exhibiting such oscillatory behaviour. The pollen tube and the surrounding medium are represented by two immiscible fluids separated by an interface. The physical variables are pressure, surface tension, density and viscosity, w...