The viscothermal wave propagation of the air inside the resonators is efficiently described by the so-called low reduced frequency model. Using this model, absorption coefficients can be calculated for different configurations. The theory has been implemented together with an optimisation algorithm, so that the dimensions of the resonators can be optimised to satisfy any desired absorption leve...

Abstract In this work, we present our results about the thermal crystallization of ion beam sputtered hafnia on 0001 SiO 2 substrates and its effect laser-induced damage threshold (LIDT). The process was studied using in-situ X-ray diffractometry. We determined an activation energy for 2.6 ± 0.5 eV. It found that growth crystallites follows a two-dimensional mode. This, in combination with high...

the khorasan region is one of the active seismic zones in iranian plateau, which is located between central iran and kopet-dagh zones. we study the crustal thickness (h) and vp/vs ratio (k) in mashhad, capital of razavi khorasan province by the receiver function method. this study uses teleseismic events recorded by an array of three broadband stations of khorasan seismic network, earthquake re...

Anatomical and functional characteristics of the teat are supposed to have considerableinfluence on milk flow performance. In the present study various teat and milkingcharacteristics in 148 quarters of 38 cows were analyzed via 3 different approaches. Teatcanal length, teat wall thickness and teat diameter were measured by ultrasound. In addition,the vacuum needed to open the t...

A two-layer quasi-geostrophic model is used to study the effect of lower boundary Ekman pumping on the energetics of baroclinic waves. Although the direct impact of the Ekman pumping is to damp the total eddy energy, either the eddy available potential energy (EAPE) or the eddy kinetic energy (EKE), individually, can grow due to the Ekman pumping. Growth of EAPE is favored if the phase differen...

The objective of this study was to evaluate the relations among electroretinogram (ERG) parameters (cone a-wave, cone b-wave, and 30 Hz flicker), retinal thickness, and retinal volume in 16 patients with central retinal vein occlusion and macular edema. The amplitude and implicit time of the ERG parameters were extracted from the ERG traces. Retinal thickness and volume were measured by optical...

The initial boundary-value problem for the Korteweg–de Vries (KdV) equation on the negative quarter-plane, x < 0 and t > 0, is considered. The formulation of this problem is different to the usual initial boundary-value problem on the positive quarter-plane, for which x > 0 and t > 0. Two boundary conditions are required at x = 0 for the negative quarter-plane problem, in contrast to the one bo...

background: fetal alcohol syndrome is associated with numerous problems in the development and function of the brain. learning and memory deficits are among well known effects of prenatal exposure to alcohol. objective: this study aimed to examine the spatial working memory of 60-day old rats who were exposed to alcohol during their fetal life and to find the relation between the possible alcoh...

We will present a detailed investigation of intersubband transitions process in core-multi shells quantum dots. The confined wave functions and eigenenergies of electrons in quantum dots have been calculated under the effective-mass approximation by solving a three-dimensional Schrodinger equation. Excellent dependence is found between size effects, time relaxation and degenerate four wave mixi...