Sound propagation outdoors is strongly affected by atmospheric turbulence. Under strongly perturbed conditions or long propagation paths, the sound fluctuations reach their asymptotic behavior, e.g., the intensity variance progressively saturates. The present study evaluates the ability of a numerical propagation model based on the finite-difference time-domain solving of the linearized Euler e...

Abstract The transient electromagnetic field generated by vertical electric dipole in evaluation duct is investigated theoretically. A vertical electric dipole in the surface layer is taken as the source of the electromagnetic field. We determine the electric field strength exactly at some fixed point in the duct layer expansion with time, the image of the primary source permits us to apply the...

During the last decade, a major research interest is focused on optical sensors for chemical and biosensing application relaying on refractive index (RI) measurements. Among this class of optical sensors the waveguides confined inside of photonic crystals are of high interest. The application of such RI optical sensors is interesting for both gaseous and aqueous samples and includes measurement...

Waves in periodic media, whose propagation is governed by nearest neighbour interaction, are investigated. The reflection and transmission coefficients are derived for a plane wave incident from medium 1 upon medium 2, without invoking common approximations. The derivation is valid for a class of waves including magnetoand electro-inductive waves, waves on short loaded dipoles, nanoparticles, c...

It is shown that under very general conditions there is a rigorous identity between the group velocity and the velocity of energy transport in nonhomogeneous media with or without anomalous dispersion. The medium is assumed nondissipative and the parameters such as density, rigidity, dielectric constant, etc., vary from point to point but are independent of the Cartesian coordinate lying in the...

The propagation environment of electromagnetic waves in mine tunnels is confined areas. The mine tunnel is regard as wave-guide which contains kinds of un-beneficial medium, the field formulas of different polarization waves were presented based on Marcatili method, and field prediction of horizontal and vertical polarization waves were simulated. The results showed that propagation effect of v...