Description of sound absorption by a flat resonator stacking metamaterial with double porosity model

A theoretical model to predict the low-frequency sound absorption of a helmholtz resonator array.

A theoretical method based on mutual radiation impedance is proposed to compute the sound absorption performance of a Helmholtz resonator array in the low-frequency range. Any configuration of resonator arrangement can be allowed in the method, while all the resonators may or may not be identical. Comparisons of the theoretical predictions with those done by the past studies or experiments show...

Experimental demonstration of terahertz metamaterial absorbers with a broad and flat high absorption band.

We present the design, numerical simulations and experimental measurements of terahertz metamaterial absorbers with a broad and flat absorption top over a wide incidence angle range for either transverse electric or transverse magnetic polarization depending on the incident direction. The metamaterial absorber unit cell consists of two sets of structures resonating at different but close freque...

a study on insurer solvency by panel data model: the case of iranian insurance market

the aim of this thesis is an approach for assessing insurer’s solvency for iranian insurance companies. we use of economic data with both time series and cross-sectional variation, thus by using the panel data model will survey the insurer solvency.

Porosity of the Flat Textiles

A Computational Model for Sound Field Absorption by Acoustic Arrays

In this paper we discuss the sound absorption property of arrays of micro-acoustic actuators at a control surface. We use the wave equation over the half plane for the velocity potential with a boundary dissipation by a proportional pressure feedback law along the half plane boundary. The feedback gain over the array is described by a distributed shape function. We develop a computational metho...