In this research the electrical conductivity measurements were made on the amorphous InAs films prepared by thermal evaporation method in thickness 450 nm and annealed in different temperatures in the range (303- 573) K.        The electrical conductivity (σ) showed a decreasing trend with the increasing annealing temperature, while the activation energies (Ea1, Ea2) showed an opposite trend, where the activation energies are increased with the annealing temperature.

The rotor dynamics generally deals with vibration of rotating structures. For designing rotors of a high speeds, basically its important to take into account the rotor dynamics characteristics. The modeling features for rotor and bearings support flexibility are described in this paper, by taking these characteristics of rotor dynamics features into standard Finite Element Approach (FEA) model. Transient and harmonic analysis procedures have been found by ANSYS, the idea has been presented to deal with critical speed calculation. This papers shows how elements BEAM188 and COMBI214 are used to represent the shaft and bearings, the dynamic stiffness and damping coefficients of journal bearings as a matrices have been found

  In this paper, we introduce and discuss an algorithm for the numerical solution of two- dimensional fractional dispersion equation.  The algorithm for the numerical solution of this equation is based on explicit finite difference approximation. Consistency, conditional stability, and convergence of this numerical method are described. Finally, numerical example is presented to show the dispersion behavior according to the order of the fractional derivative and we demonstrate that our explicit finite difference approximation is a computationally efficient method for solving two-dimensional fractional dispersion equation

  The main purpose of this work is to find the complete arcs in the projective 3-space over Galois field GF(2), which is denoted by PG(3,2), by two methods and then we compare between the two methods

        In this research, an investigation for the compatibility of the IRI-2016 and ASAPS international models was conducted to evaluate their accuracy in predicting the ionospheric critical frequency parameter (f_oF2) for the years 2009 and 2014 that represent the minimum and maximum years of solar cycle 24. The calculations of the monthly average f_oF2 values were performed for three different selected stations distributed over the mid-latitude region. These stations are Athens - Greece (23.7^o E, 37.9 ^o N), El Arenosillo - Spain (-6.78 ^o E, 37.09 ^o N), and Je Ju - South Korea (124.53 ^o E, 33.6 ^o N). The calculated v

Nanocomposite of carbon nanotube add to epoxy resin material of weight fraction ( 0.25, 0.5, 0.75 1.0, 1.25, 1.5, 1.75 , 2 & 2.5 wt. % ) were fabricated by dispersing within an epoxy resin using a Ultrasound machine followed by mechanical stirring. The samples were heat treated at temperature ( 80 °C for 3 hrs) The mechanical properties of the composites were investigated. Wear and hardness properties measurements indicated higher wear rate and hardness with increasing concentration of MWCNTs . The MWCNTs significantly improved the wear resistance and hardness when compare than the pure epoxy. These note show too after heat treatment of composite with ( 80 oC for 3 hrs ).

    The goal of this research is to use optical emission spectroscopy to investigate the parameters of exploding silver wire plasma. The silver discharge plasma's emission spectra were recorded and studied. For silver wire of diameter 0.4 mm and different currents 75,100, and 125A in deionized water, the plasma electron temperature ( ) was calculated by Boltzmann plot and container plasma medium temperature by thermal camera, and the electron density ( ) was computed by Stark broadening using the hydrogen (H line) at 656.279 nm With increasing current from 75 to 125 A, the electron density (n_e) increased from 3.160×  to 8.762×   , while electron temperatures increased from 0.571 to 1.334 eV under the same conditions. 

Broadband satellite is playing a main role in provision global coverage and onboard processing ability over IP networks to assess user applications. In order to lower the cost, get better security, solve IPv4 addressing limitation, expand the expected advantages of modern routing and mobility characteristics; the next-generation satellite systems ought to support IPv6 and seamlessly incorporate with terrestrial networks including wireless local loops. Satellite communication links have a number of limitations compared to terrestrial communications networks such as large delay and high header overhead for IPv6 consumes the bandwidth and causes lower transmission effectiveness; however, the quality of service (QoS) (such as delay, jitter,