This study has been motivated by the observed difference in the range of the power-law attenuation exponent for compressional and shear waves. Usually compressional attenuation increases with frequency to a power between 1 and 2, while shear wave attenuation often is described with powers less than 1. Another motivation is the apparent lack of partial differential equations with desirable prope...

Phononic crystals (PCs) are periodic structures obtained by the spatial arrangement of materials with contrasting properties, which can be designed to efficiently manipulate mechanical waves. Plate modeled using Mindlin–Reissner plate theory and have been extensively used analyze dispersion relations PCs. Although analysis propagating characteristics PCs may sufficient for simple elastic struct...

This paper develops new fractional calculus models for wave propagation. These models permit a different attenuation index in each coordinate to fully capture the anisotropic nature of wave propagation in complex media. Analytical expressions that describe power law attenuation and anomalous dispersion in each direction are derived for these fractional calculus models.

In recent years, borehole Stoneley wave amplitude and reflectivity have been used for estimating formation permeability based on the strong correlation between Stoneley wave attenuation, reflectivity and formation fluid conductivity. There are other factors, however, that may cause substantial Stoneley attenuation and reflection in a borehole environment. To make better use of Stoneley measurem...

This paper presents the design of Electromagnetic Bandgap (EBG) structure using fractals geometry and its effect on antenna performance. The EBG structure has been designed on substrate єr = 4.3 and thickness h = 1.53 mm. The 1 iterative EBG structure offers the surface wave attenuation around 20 dB down from 2.94 GHz to 4.58 GHz corresponds to 43.62% bandwidth. The experimental results of 2 it...