Computer modeling has been used to investing the Coulomb coupling parameter ?. The effects of the structure parameter K, grain charge Z, plasma density N, temperature dust grain Td, on the Coulomb coupling parameter had been studied. It was seen that the ? was increasing with increasing Z and N, and decrease with increasing K and T. Also the critical value of ? that the phase transfer of the plasma state from liquid to solid was studied.
Carbon nanotubes were prepared by an arc-discharge method,
under different values of pressure of oxygen gas. The structure of
multi-walled carbon nanotubes powders has been characterized by
low-angle X-ray diffraction .The morphology of carbon nanotube
powder was examined by transmission electron microscope. The
capacitance-voltage and current- voltage (dark and illumination
current) characterization were measured under different values of
pressure (10-3, 10-4, 10-5) mbar of oxygen gas
Titanium dioxide (TiO2) thin films were prepared under different pressures with values (15, 30, 60 and 120) Pa using the DC reactive magnetron homemade system with mixed gases of argon and oxygen in ratio (50:50). The result of X-ray diffraction patterns discovered that the structure of the deposited films was polycrystalline, including the phase of anatase. All the appeared peaks were matched to the planes (101), (004), (105), and (211) of diffracted states. Both the intensities and the number of the appeared peaks are declined according to the increased pressure, and the plane of (101) is be considered the preferential grown plane, it is taking a maximum texture factor. Both the lattice constant and the atomic inter-planer spacing take th
... Show MoreA modified Leslie-Gower predator-prey model with a Beddington-DeAngelis functional response is proposed and studied. The purpose is to examine the effects of fear and quadratic fixed effort harvesting on the system's dynamic behavior. The model's qualitative properties, such as local equilibria stability, permanence, and global stability, are examined. The analysis of local bifurcation has been studied. It is discovered that the system experiences a saddle-node bifurcation at the survival equilibrium point whereas a transcritical bifurcation occurs at the boundary equilibrium point. Additionally established are the prerequisites for Hopf bifurcation existence. Finally, using MATLAB, a numerical investigation is conducted to verify the va
... Show MoreA modified Leslie-Gower predator-prey model with a Beddington-DeAngelis functional response is proposed and studied. The purpose is to examine the effects of fear and quadratic fixed effort harvesting on the system's dynamic behavior. The model's qualitative properties, such as local equilibria stability, permanence, and global stability, are examined. The analysis of local bifurcation has been studied. It is discovered that the system experiences a saddle-node bifurcation at the survival equilibrium point whereas a transcritical bifurcation occurs at the boundary equilibrium point. Additionally established are the prerequisites for Hopf bifurcation existence. Finally, using MATLAB, a numerical investigation is conducted to verify t
... Show MoreThe futuristic age requires progress in handwork or even sub-machine dependency and Brain-Computer Interface (BCI) provides the necessary BCI procession. As the article suggests, it is a pathway between the signals created by a human brain thinking and the computer, which can translate the signal transmitted into action. BCI-processed brain activity is typically measured using EEG. Throughout this article, further intend to provide an available and up-to-date review of EEG-based BCI, concentrating on its technical aspects. In specific, we present several essential neuroscience backgrounds that describe well how to build an EEG-based BCI, including evaluating which signal processing, software, and hardware techniques to use. Individu
... Show MoreA computerized investigation has been carried out to design an immersion lens
with low aberration operating under zero magnification condition using inverse problem.
The aberration is highly dependent on the shape of electrodes, for a preassigned electron
beam trajectory the paraxial-ray-equation is solved to determine the electrostatic potential
and field distribution.
From the knowledge of the potential and its first and second derivative the
electron optical properties were computed, the electrode geometry was determined from
the solution of Laplace equation.
A number of glow discharge experiments has been carried out in a relatively large-volume metallic vacuum chamber containing argon at low pressure and immersed in an inhomogeneous magnetic field generated by a solenoidal coil capable of delivering 2100G. Two Paschen curves demonstrating the dependence of the discharge voltage on sparking parameter Pd and magnetic field strength B were deduced. A graphical correlation showing the behaviour of the voltage difference from the two curves on the ratio B/Pd was constructed. Investigations showed a reduction in the nominal impedance of the discharge device of nearly 20% when B reaches a value of 525G. Plasma confinement regions were found around the internal surface of the chamber at the entranc
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