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The purpose of this work is to highlight the effects of partial unipolar injection on electro-thermo-convection (ETC) in dielectric liquid contained between two eccentric cylinders.

A finite volume method was used to solve governing equations. The study is performed for different parameters, such as radius ratio (0.2 ≤ Γ ≤ 0.6), dimensionless electric Rayleigh number (0 ≤ T ≤ 900), eccentricity (−0.4 ≤ e ≤ 0.4) and thermal Rayleigh number (10 ≤ Ra ≤ 5.105).

It is found that heat transfer increases with increase in dimensionless electric Rayleigh number and eccentricity ratio.

The originality of this work is to analyze the ETC in dielectric liquid subjected to partial unipolar injection between two eccentric cylinders

Presents a simplified mathematical model of electron transport in a one‐dimensional semiconductor device of N+ ‐ N ‐ N + type. The model is based on a singular perturbation approach of the kinetic equation which describes the transport processes. This so‐called Child‐Langmuir asymptotics is obtained by assuming that the injected electrons at the N + ‐ N junction on the source side have a very weak energy compared with what they are able to gain under the influence of the electric field. Formally establishes the limit model when a realistic collision model for electron‐phonon interaction is considered. Compares the results with both experiments and particle simulations.

The purpose of this study is to develop a new approach for simulating the ion flow field with the floating conductors based on the existing inversion method.

The space charge keeps charging the floating conductors until the dynamic balance is reached. The corresponding floating potential boundary condition is linearized as the combination of the equipotential constraints and natural boundary condition, which can be directly imposed in the inversion process.

The numerical results demonstrate that the modified inversion algorithm performs well in the ion flow field with the floating conductors and the floating potential converges within five steps’ iterations. The proposed approach is applied to investigate the effect of the grounded line to the floating conductors in the practical high voltage direct current (HVDC) transmission lines.

The modified inverse algorithm provides a general way to deal with the Kapzov hypothesis and the floating boundary condition simultaneously within one loop, which can be applied to the multiphysics systems with different kinds of irregular boundary conditions.

This paper aims to propose a new transformer-less inverter structure to reduce the common-mode leakage current in grid-connected photovoltaic (PV) systems.

The proposed circuit structure is the same as the conventional full-bridge inverter with three additional power switches in a triangular structure. These three power switches are between the bridge and the output filter, and they mitigate the common-mode leakage current flowing toward the PV panels’ capacitors. The common-mode leakage current mitigation is done through the three-direction clamping cell (TDCC) concept. By clamping the common-mode voltage to the middle voltage of the DC-link capacitors, the leakage current and the total harmonic distortion (THD) of the injected current to the grid is effectively reduced. Therefore, the efficiency is improved.

The switching modes and the control method are introduced. A comparison is carried out between the proposed structure and other solutions in the literature. The proposed topology and its respective control method are simulated by PSCAD/EMTDC software. The simulation results validate the advantages of the presented structure such as clamping the common-mode voltage and reducing leakage current and THD of injected current to the grid.

Presenting a single phase-improved inverter structure with low-leakage current for grid-connected PV power systems represents a significant original contribution to this work. The proposed structure can inject a sinusoidal current with low THD to the AC grid, and the power factor is unity on the AC side. In the half positive cycle, one of the switches in the TDCC is turned off under zero current. Besides, one of the other switches in TDCC is turned on with zero voltage and, therefore, its turn-on switching losses are zero. The efficiency of the proposed topology is high because of the reduction of leakage current and power losses. Accordingly, the presented topology can be a good solution to the leakage current elimination.

This paper aims to investigate an improved control method and digital signal processor-based (DSP-based) digital implementation of three-phase standalone inverter. The proposed method is performance developed of the proportional-resonant controller (PRC) with harmonic injection technique, aiming to improve load voltages quality under different loads, especially nonlinear loads. The advanced proposed multi-loop controller is consisted of current harmonic loops for suppressing odd harmonic, which are analyzed in discrete-time domain. Besides, the voltage loop is also used to compensate the output capacitor voltage.

The proposed method can effectively enlarge output voltage stability with low total harmonics distortion and improve the dynamic transient response. The other advantage of the proposed PRC is the injection of the selective harmonic without any additional calculation compensator.

The method is given the opportunity to be controlled exactly all harmful outputs with high-quality voltage referenced of the standalone inverter. The proposed method is implemented using a DSP processor (TMS320F28335) and is verified on the 10 kVA three-phase standalone inverter prototype.

The proposed method is performance developed of the PRC with harmonic injection technique, aiming to improve load voltages quality under different loads, especially nonlinear loads.

While the transference of charge is an essential aspect of every capacitance sensor, a relatively new form of sensor makes overt use of the principle of charge conservation first deduced by Watson in the 1740s. Updated to use a microcontroller, mosfet switches, fet‐input opamps and band gap references, the principle of charge transference can be used to create an extremely sensitive and stable device with unique properties that transcend those of more pedestrian capacitance sensors. Also known as “QT” sensors, charge transfer sensors can have a dynamic range spanning many decades with noise floors in the sub‐femtofarad regime, allowing differential resolutions of mere fractions of a femtofarad. Such sensors are proving to have unique applications considered heretofore impossible, while also proving themselves as replacements for much more expensive sensing systems using photoelectric, acoustic, RF, and optical imaging techniques.

The purpose of this paper is to deal with the self-heating of semiconductor nano-devices.

Transport in silicon semiconductor devices can be described using the Drift-Diffusion model, and Direct Simulation Monte Carlo (MC) of the Boltzmann Transport Equation.

A new estimator of the heat generation rate to be used in MC simulations has been found.

The new estimator for the heat generation rate has better approximation properties due to reduced statistical fluctuations.

The purpose of this paper is to study the industrial separation of granular mixture by approximation of combined corona‐electrostatic electric field with feeder and inductive electrostatic electrode.

The original numerical method developed in Caron's Kybernetes paper is used and extended to an industrial construction. The method gives a mathematical model of an industrial process and converts the non‐linear partial derivative system into an iterative system of linear equations. Using the well‐known finite difference approximation, a numerical solution is computed very quickly.

In order to really obtain a computer‐aided numerical solution, it is necessary to define a really manageable approximation method. The new simulation results are detailed and show better results for the steady state in time processing and finally, to imagine improvements of the industrial processes.

The paper shows the fast numerical solution, which leads to confidence in the numerical approximations to imagine improvements of the industrial processes easily.

The purpose of this paper is to add precisions to a method, to demonstrate the convergence, to explain time and memory space complexities and new simulated results on a non‐linear partial derivative equation system governing corona‐electrostatic electric field for granular mixture separation.

The method converts the non‐linear partial derivative system into an iterative system of linear equations. Using the well‐known finite difference approximation, a numerical solution is computed very quickly.

The paper gives the truncated error and the approximation error to conclude to the convergence.

The paper shows the fast numerical solution leads to confidence in the numerical approximations for the comprehension of the phenomenon. Extends the corona‐electrostatic electric field for granular mixture separation to new geometries easily.

The purpose of this paper is to investigate a novel approach toward electromagnetic launch.

The field of linear electromagnetic acceleration aims at accelerating macroscopic masses (up to several kg) to speeds in excess of 2 km/s. This can be achieved using accelerators of the railgun type. The innovation of this work lies in the use of multiphase current instead of the classically used quasi-direct current (DC). The approach taken is to work out in a first step the potential performance of such a configuration, for example, by showing that a constant propulsive force can be realized. Next, the necessary changes for the system setup were carefully analyzed. Both the accelerator and the power supply have to be considerably modified with regard to the classical approach.

Thorough analysis of the electromagnetic behavior of the launcher including nonlinear effects lead to an innovative system design which is considered to be the main finding of the work presented here. Moreover, a prototype was build. The preliminary experimental results obtained are in very good agreement with corresponding simulations validating the underlying modeling approach.

For the purpose of this paper, power levels of only 450 kVA are considered. However, this research can be used to design more powerful devices in the future.

While DC powered railguns are modeled very well in a variety of papers, the use of multiphase alternating current is not very well discussed yet. It could be of value for launch scenarios, for which very high speeds are required such as the launch of micro satellites to space.