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In this article, we are reporting about the effect of energy and number density of hot primary electrons on plasma parameters in a new experimental configuration of a double plasma device. Here, we have controlled the plasma parameters in two plasma regions by a single discharge circuit. The discharge voltage is applied between hot filaments and a mesh grid. The energy of the hot primary electrons is increased by increasing the discharge voltage, and their number density is increased by increasing the filament heating voltage. It has been observed that the variations in plasma parameters are significant when the number density of primary electrons is increased.

In this paper, the flow problem of constant velocity of a square cavity whose lid is solved and obtained a numerical solution on 2 grid levels, having 32x32 and 64x64 cells. Reynolds number of 1x102 , 1x103 was selected for laminar flow and 8x103 was selected for turbulent flow. The problem is identified in NavierStokes equations. The finite volume discretization is based on the numerical model. The simulated results are in valid agreement with those that are available in the given report. The numerical solution of these works are accurately obtained for this problem.

The projector augmented wave (PAW) method is a powerful numerical algorithm that serves as a backend, enabling efficient density functional theory (DFT) calculations through the smoothing of valence electronic descriptions. Although it is mainly used in conjunction with plane-wave basis for solid-state systems, its generality permits the combination with other types of basis functions. In the previous study, we proposed a scheme to incorporate the PAW method into the conventional quantum chemical DFT implementation based on Gauss-type function (GTF) basis (Xiong et al.

The newly designed and constructed electrostatic quadrupole doublet (EQD) at the University of North Texas (UNT) has achieved mass independent focusing of MeV particles to a spot size of 3.3 × 3.5 μm. The EQD is compared to the Louisiana magnetic doublet which is also in use at UNT. Characteristics such as demagnification and sensitivity to aberrations are simulated by the matrix raytracing software, propagation of rays and aberrations by matrices and compared for each focusing system. Particle induced x-ray emission (PIXE) maps of a 2000 mesh Cu grid are compared and show that both doublets produce suitable spot sizes for microprobe analysis. A coarser, 200 mesh grid and incident beams of 2 MeV H+ and O+ show the EQD to be stigmatic given common aperture sizes and lens potentials.

A numerical simulation based on a new regularized phase-field model is developed to describe the silicon solidification in a forced flow. The effect of forced flow, anisotropy, and mesh grid on dendritic growth shape is investigated. These results indicate that crystals grow into an equiaxial facet dendritic without flow and into an asymmetrical facet dendritic with flow, that is, upstream arm growth is promoted, and downstream inhibited, however, there is no such effect on perpendicular arms. It is also found that the asymmetrical growth feature becomes noticeable with increase in the flow velocity. With the increase in the anisotropy value, the tip velocities of upstream and downstream decrease gradually.

The dynamical behavior of two coupled chaotic oscillators caused by current-driven ion acoustic instability is experimentally studied. It is found that when two oscillators are interacting with the mediation of a central mesh grid, and the DC potential applied to either of the two oscillators is varied gradually while maintaining coupling, the two oscillators synchronize in a certain region.

A new non-local algorithm for accurately calculating the band-to-band tunneling current suitable for TCAD semiconductor simulators is proposed in this abstract. The proposed algorithm captures the essential physics of multi-dimensional tunneling in a 2D structure, and is designed to be robust and to achieve independence on the mesh grid. The new algorithm enables accurate modeling of T-FET and investigation of its device physics. Application on T-FET is demonstrated. The physical origin of the saturation of I d -V d curve of T-FET is analyzed and clarified for the first time.

Coherent low-frequency oscillations whose frequency is lower than the ion plasma frequency are generated by a mesh grid with negative d.c. bias in a double-plasma device. The frequency is inversely proportional to the one-quarter power of the grid voltage under a fixed plasma density, and is proportional to the ion plasma frequency when the grid bias is kept constant. With potential profiles near the grid, which are measured by an emissive probe, the transit time of ions is numerically calculated. The inverse of the transit time agrees well with the oscillation frequency. The oscillation is considered to be excited by a klystron bunching effect of incident ions towards the ion-rich sheaths.

As indicated by tests on several cameras, the dynamic range of the Lawrence Livermore Laboratory streak-camera system appears to be about two orders of magnitude greater than those reported for other systems for 10- to 200-ps pulses. The lack of a fine mesh grid in the RCA streak tube used in these cameras probably contributes to a lower system dynamic noise and therefore raises the dynamic range. A developmental tube with a mesh grid was tested and supports this conjecture. Order-of-magnitude variations in input slit width do not affect the spot size on the phosphor or the dynamic range of the RCA tube.

In this chapter we shall consider the use of a digital computer in the design of magnetic lenses. Problems which can be solved satisfactorily without the use of a computer are treated in the preceding and the subsequent chapters.

Single pulsed ion-acoustic waves are excited by a mesh grid, the measured waveform of which agrees with the theoretical one.