one of the main principles of resistance economy, is to support domestic production and limiting imports, especially in sectors where there is the possibility of import-substituting production .this requires adjustment of exact trade policies,and to achieve this, identifying the structure of imports demand function and also price and income elasticity of import demand is necessary.this necessit...

Measurements and predictions have been made of the absorption coefficient and the surface acoustic impedance of poroelastic plates clamped in a large impedance tube and separated from the rigid termination by an air gap. The measured and predicted absorption coefficient and surface impedance spectra exhibit low frequency peaks. The peak frequencies observed in the absorption coefficient are clo...

Changes in the Young elasticity modulus in perpendicular direction to the membrane surface E perpendicular, in the coefficient of dynamic viscosity eta, in the electric capacitance C, in the surface charge U1, in the conductivity g and in the coefficient of non-linearity beta of current-voltage characteristic caused by insulin were studied in bilayer lipid membranes (BLM) prepared from a mixtur...

Abstract. The dynamic stability problem is solved for onedimensional structures subjected to time-dependent deterministic or stochastic axial forces. The stability analysis of structures under time-dependent forces strongly depends on dissipation energy. The simplest model of viscous damping with constant coefficient was commonly assumed in previous papers despite the fact that there are other ...

Nanobiocomposites of poly(lactic acid) (PLA) with 3–5 wt% organically modified montmorillonite (OMMT) were prepared by melt compounding in two different mixers, miniature twin-screw extruder and internal batch mixer, leading to different degrees of dispersion. The progress of dispersion was characterized by melt rheology coupled with light attenuation. Processed PLA/OMMT samples showed percolat...

The limit behaviour of a linear one-dimensional thermoelastic system with local mass perturbations is studied. The mass density is supposed to be nearly homogeneous everywhere except in an ε-vicinity of a given point, where it is of order ε−m, with m ∈ R. The resonance vibrations of the string are investigated as ε→ 0. An important ingredient of the analysis is the construction of an operator i...

The presence of hydrogen can affect elastic properties and seismic velocities of minerals in the Earth's upper mantle. In this study, the secondorder elastic constants of hydrous wadsleyites containing 0.37, 0.84, and 1.66 wt.% H2O were determined by Brillouin scattering at ambient conditions. Measurements were performed on at least three independent crystal planes for each composition. The agg...

In this research, the demand function of drinkable  water in Qazvin Province was estimated using dynamic and static methods. The required data were collected from the data of the provinces of Qazvin in the time period (1996-2016) and collected by referring to the statistical system of Statistics Center of Iran and the provincial planning and budget organization of Qazvin Province. The explanato...