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This thesis provides an in-depth study of the design and performance optimization of fast charging systems for electric vehicles to meet the growing demand of the electric vehicle market. Fast charging systems play a crucial role in the field of electric vehicle charging, and their performance and reliability directly affect the development of electric vehicles. This paper focuses on the key components and design of fast charging systems, including optimization of charging piles and interfaces, power management and charging control, as well as battery management and performance enhancement strategies. In addition, this paper examines performance optimization strategies, including improving charging speed and efficiency, temperature management and thermal control, charging power allocation, and user experience and safety considerations. Meanwhile, this paper explores the concept of wireless charging technology for vehicles, providing innovative ideas for future charging methods for electric vehicles. The continuous improvement of fast charging systems for electric vehicles will drive the electric vehicle industry forward and provide a more convenient and environmentally friendly solution for future sustainable transportation modes. [ABSTRACT FROM AUTHOR]

The application of high voltage, short duration electric pulses to the cell membranes and tissues increase their permeability by creating temporary pores within the cell membranes and tissues. It stimulates the delivery of extracellular materials into the cell, finding diverse applications in medicine for drug delivery and treatment of tumor. This phenomenon of physical transfection is known as electroporation. This paper presents an efficient circuit design for the generation of nanosecond pulses for electroporation applications. A Marx generator with two stages of insulated gate bipolar transistors (IGBT), resistors and capacitors are used in the proposed circuit in order to induce optimized pulses that produce enough electric field for obtaining high voltage across the load. In this circuit, high voltage (100V) nanosecond pulses are generated with different pulse width 10ns, 2ns and 1ns. By varying the number of IGBT stages, different nano second pulses can be generated for different applications of electroporation. The proposed design approach aims to produce controlled electric pulses in the nano-second range with reduced switching losses and harmonic distortion. [ABSTRACT FROM AUTHOR]

In the 1933 Bohr and Rosenfeld’s famous article on electromagnetic field measurements they did not consider the measurement of a magnetic component in a given space-time region, nor the measurement of two parallel magnetic components, nor the measurement of two non-parallel magnetic components, nor the parallel measurement of one magnetic and one electric component, nor the non-parallel measurement of one electric and one magnetic component, nor the non-parallel measurement of one magnetic and one electric component in two different space-time regions. This article covers the first one of these pending matters. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

The main aim of the present manuscript is analysis, and simulation different type silicene nanoribbons with edges modified by hydrogen, used in modern semiconductors. The focus of this paper is investigation the main characteristic and parameters of doping a Bi atom in the unit cell of silicene nanoribbons. The experiments are carried out with external electric field with intensity 0.1V/A. In our study we used Angstrom (A) for distance measurement, because the approximate orbital diameter of one electron in a hydrogen atom is smaller, the atomic lattice spacing in most crystals is of the same order. On the base of the conducted classification we proposed and studied two different atom configuration - the top configuration and the valley configuration. In our investigation we used density functional theory (DFT) and applied methods for synthesis and calculation of the formation energy of the doped system. The obtained result show that the optimal configuration is the top configuration. On another hand we calculated the state densities of the doped configurations and energy band of investigated structures. The contributions of the partial states Si(s), Si(p), Bi(s), Bi(p) are also analyzed. [ABSTRACT FROM AUTHOR]

The paper demonstrates a study of charge process taking place in thermal SiO2 films of MOS structures under a concurrent influence of high-field tunnel injection of electrons by Fowler-Nordheim and an ionization radiation. We make a special attention to study of an influence of a redistributing of local electric fields in the dielectric film which is because of an accumulation of positive charge in its bulk. We demonstrate that the accumulation of positive charge in conditions of constant injection current flowing can significantly lower electric filed for the most section of the dielectric film. The paper proposes a model describing charge processes in MOS structures with thermal silicone dioxide films. The model takes into consideration the generation of holes under both the radiation and high-field ionizations, by the annihilation of a fraction of the trapped holes caused by an interaction with injected electrons. Moreover, the model takes into account the redistributing of electric fields in the bulk of silicone dioxide. [ABSTRACT FROM AUTHOR]

In this paper, we have investigate the effect of kappa distribution function in the presence of parallel electric field by using the method of kinetic approaches are discussed. The kinetic method has been adopted to obtain the dispersion relation, growth rate and growth length of the electromagnetic ion-cyclotron waves in minimum low βcondition (β is the part of plasma pressure to magnetic pressure), homogeneous plasma has been obtained. In this paper, the effect of kappa distribution in presence of parallel electric field EII on EMIC waves in magnetosphere plasma is to enhance the damping/growth rate with increases the growth length of EMIC waves in low β condition. The results are interpreted for the space plasma parameters appropriate to the auroral acceleration region. The results of the work is consistent for EMIC emissions observations by Polar, FAST and S3-3 satellite of the auroral acceleration region as reported by [1,2] as well as the astrophysical and astronomical applications of these processes. [ABSTRACT FROM AUTHOR]

A strong electromagnetic field polarizes the vacuum and in the presence of an electric field creates pairs of a charged particle and its anti-particle. Magnetars, highly magnetized neutron stars with magnetic field comparable to or greater than the Schwinger field, give a significant amount of the vacuum polarization and vacuum birefringence and the induced electric field can create the electron-positron pairs, which are strong field quantum electrodynamics (QED) processes. In this paper, we use a closed formula for the one-loop effective action in the presence of a supercritical magnetic field and a subcritical electric field, find the vacuum birefringence analytically and numerically, and then discuss possible measurements in magnetars. [ABSTRACT FROM AUTHOR]

A healthy consumable fruit products demands is highly increase over time. This is mainly due to the need of high-quality food increase as the economic is better and also because of healthy reason. Fresh fruits drink is always requested by costumer, however this is not always available in the market due to some reasons. Thus, processed fruit juice might be a substitution for fresh product. However, during food process, the fruit juice quality might decrease as the juice prone to the pollutant during the process and keeping time. So, it is needed to provide a packing process that able to reduce or even eliminate pollutant during the processing and storing. One of the most dangerous pollutants is pathogenic microorganism such as Escherichia coli. If consumed, Escherichia coli can cause diarrhea which could lead to severe stomach ache. In this paper, discussed food juice treatment by using pulse electric field generated by tesla transformer to disinfect the fruit juice thus eliminate the microorganism. A prototype of the food juice treatment system is built by using a Tesla transformer to produce high voltage thus generate pulse electric field which then will be used to eliminate microorganism. [ABSTRACT FROM AUTHOR]

This paper presents the electric field and specific absorption rate (SAR) distribution in the multilayered skin tissue exposed to 5G mobile frequencies, viz. 28 GHz, 38 GHz and 60 GHz. Presently, the safety limits for electromagnetic wave exposure above 6GHz are expressed in terms of power density by Federal Communications Commission (FCC). This study estimates the SAR values compliant to mentioned power densities. Inthe numerical scheme, Maxwell’s equation is employed to determine electric field, and SAR is estimated using electric field values. Results show that most of the energy associated with the 5G frequencies is absorbed in epidermis layer of skin tissue. Maximum electric field and SAR values are predicted in skin tissue exposed to 38 GHz radiation, while least electric field and SAR values are found at 60 GHz. 60 GHz can be considered the safest among all three frequencies for 5G mobile communications. [ABSTRACT FROM AUTHOR]

Speed estimation problem stands viral for the field of electric drive control theory. This paper presents a study of two angular speed estimation methods of AC motor drives. On the example of an induction motor drive with direct stator field vector control speed feedback and with speed monitors, a comparative analysis is carried out. A comparative analysis of classical model-reference adaptive system and a neural network speed estimator is given. The study analyzes the effectiveness of well-known artificial neural network-based techniques and shows how they can be strengthened using some expert knowledge. Whereas many researchers denote that using black-box concept in electrical drives parameters estimation does not give the best solutions. Better results could be achieved by involving known relations between the estimated parameter and the other known parameters of the drive. Here come the so-called grey-box techniques, where expert knowledge supports the estimation algorithms. [ABSTRACT FROM AUTHOR]

In this paper, a hetero-junction tunnel-field-effect-transistor (TFET) using pocket engineering is proposed. The TCAD analysis of nTFET was carried out varying the different design parameters to get an optimized values. Furthermore, the transfer characteristics and output characteristics of optimised nTFET and pTFET has been obtained at different drain and gate voltages. Similarly, the different other characteristics of the device like electric field intensity, energy band diagram, and surface potential along the length of the device were simulated in TCAD tool. From the simulation results, it has been found that the ON-state current increases as the applied gate voltage is increased. For every simulation study, a proper comparative analysis of both devices has been performed. The improved performance of both nTFET and pTFET can results in good performance inverter circuit. The optimization of device using simulation tool is highly recommended to check the device characteristics. [ABSTRACT FROM AUTHOR]

Polymeric insulators are among the most crucial components in a power transmission system. The electric field (EF) distribution and voltage on the insulators' surface affect the insulators' performance and service life. Several experimental and numerical methods for calculating and studying the EF. This paper utilized corona rings at both ends to minimize the value of the EF and improve potential distribution along the surface of the 765-kilo Volt polymer insulator-based two-dimensional finite element method (FEM). At first, the mathematical relationship linking the EF to the parameters of the corona rings (corona ring radius, ring tube thickness, and vertical location of the ring) was established to calculate the EF strength and influence of the corona ring parameters. Then, optimization techniques within the COMSOL Multiphysics are utilized to optimize the position and diameters of the corona rings and lower the EF at the insulator's surface. According to the results, the optimization procedures utilizing the Nelder-Mead technique reduced the high value of the EF by 70% compared to the EF value with the original corona rings. [ABSTRACT FROM AUTHOR]

Ceramic Insulators are used as electrical insulators ever since the introduction of power system. These insulators provide mechanical strength to the live lines and electrically isolate them. Because of its rigid structure, heavy weight, more over pollution flash-over, which is one of the main disadvantages, they are being replaced by polymeric insulators, these days. These polymeric insulators are light in weight and are comparatively less prone to pollution flashover because of its hydrophilic nature and are gaining more popularity these days. In the manufacturing process of these insulators, the check on polymeric materials used becomes very important as, the life of polymeric materials depends on the composition of materials used in producing the insulators. In this paper, polymeric material samples with different compositions of SiR are evaluated for their electrical and mechanical properties. The electric field simulation of polymeric material sample is carried out using ANSYS software. An attempt has been made to bring out best composition of Silicone Rubber material which can have better performance of insulator. [ABSTRACT FROM AUTHOR]

The receiver tube for parabolic trough collectors is one of the main components of the solar field in a thermal electric plant. Optical and thermal properties of the solar receiver tube are critical in order to assure a good energy production of the solar plant. An accurate characterization of those parameters is crucial when selecting the most suitable tube from different manufacturers. In this paper, a summary of the current testing methodologies used at CENER and TEKNIKER is given following the actual standard testing methodology in order to obtain the solar absorptance and the thermal emittance at different temperatures using different testing bench and equipment. [ABSTRACT FROM AUTHOR]

Spacers are a key component of the gas-insulated structures. Most dielectric instances intensity collapses and ground flashover are attributed to distinguish the failures of spacer. Such Failures are due to non-uniformity distribution of electric field around the top of the spacer and high field tension at triple junctions. For a better electric field distribution, precise structure simulation of the spacers is important as it improves the component's existence. Rare pressure management results in problems such as moulding and manufacturing by shape modeling. In this paper, a graded high FGM insulating spacer is designed for a Single phase GIS for reduction of electric field stress. Stress in the electrical field for different values of high grading the FGM material is measured and the insertion of metal inserts is used to reduce the electrical field pressure. [ABSTRACT FROM AUTHOR]

High voltage power equipment is becoming more compact and under high stress, resulting in loss of insulation. The construction of insulators plays a vital role in enhancing the system's reliability. For GIS, the solid supporting structures called spacers are vulnerable to increased stress and are concerned about their functionality. The point of contact of the conductor, gas and spacer called the triple point junction in the air-insulated bus duct is a highly stressed area and is responsible for significant insulation failures. GIS switchgear design requires comprehensive field distribution in the supporting structures called spacers, which is critical for the system's healthy operation. In this paper, high grade material is used for post form spacers with specific permittivity for controlling field stress distribution on the spacer surface. Electric field calculations for different grades are calculated and compared and the stress reduction is carried out with the insertion of metal inserts. [ABSTRACT FROM AUTHOR]

High voltage electrical systems are plagued by certain problems, such as high stress delivery and damage to insulation, which are necessary to ensure efficient network service High pressure on the spacer surface in a gas-insulated bus duct is a major factor influencing the insulation strength , particularly at the conductor, insulator and gas contact point (called triple junction).Research studies of spacer shaping have been found to be effective in managing pressure distribution but difficult in real-time applications. In this paper, for the regulated field stress division on the spacer layer, dynamically graded post-type spacer materials with dissimilar low graded permittivity are planned. Electric field calculations for low graded materials are performed and a uniform distribution of stress along the spacer is achieved by correctly designed metal inserts integrated in GIS. [ABSTRACT FROM AUTHOR]

There has been an enormous focus on low-dimensional layered transition metal dichalcogenides (TMDs) for new futuristic electronic device fabrication. In this paper, we report the density functional theory based calculations of electronic properties of two dimensional (2D) and one dimensional (1D) heterostructures of ZT-MoSe2/PdSe2. The Schottky barrier with p-type contact changes to n-type contact by applying an external electric field and finally into ohmic on further increase in the electric field. The dangling bonds present on the edges of the 1D heterostructure are important to decide its electronic structure which changes from metallic to semiconductor on edge passivation. [ABSTRACT FROM AUTHOR]

In this paper a one-dimensional approach to the lower hybrid current drive (LHCD) modelling in the presence of inductive electric field is applied to calculate LHCD for deuterium plasmas at the FT-2 tokamak. The simulation results are compared to experimental data. [ABSTRACT FROM AUTHOR]

Coupling issues for ion cyclotron range of frequency (ICRF) are an essential element restricting the steady-state high performance operation on EAST. In this paper, we present the simulations of ICRF power injected into 3D EAST plasmas via the high performance Finite-difference time-domain (FDTD) model in VSim software. Realistic 3D ICRF antenna module and box of the B-port on EAST have been constructed as geometry in the simulations. The wave pattern is affected by the shape of current strap. Edge power loss is significantly reduced by the top and bottom structures of the antenna box. In order to prevent artificial reflection at the simulation periphery, we construct a MAL (Matched Absorbing Layer) outgoing wave boundary on the ends of simulation. We discuss the effect of antenna phase on the wave patterns and estimate the parallel wavenumber in front of the antenna. When we move the plasma closer to the antenna in the simulation, the gapout (width of cut-off region) decreases so that more ICRF power transmits into the plasma core, which is consistent with experiments on EAST. The amplitude of the electric field attenuates exponentially with the gapout, agreeing with the linear theory in the cut-off region. In the simulations, plasma with hydrogen minority shows stronger damping than pure deuterium plasma near the cyclotron resonant layer. [ABSTRACT FROM AUTHOR]

The paper considers a model of the formation of warm thunderstorms, which takes into account the fractality of the medium. A fractal-dynamic equation of charge accumulation (change) in a warm bipolar cloud with a positive field direction is obtained, which is a fractional analogue of the charge accumulation process by the lower charged region of the cloud. The equation of the dynamics of the electric field intensity in warm thunderstorms is obtained. Solutions of the model equations are found analytically. Using numerical calculations, the dependence of charge accumulation and electric field strength in warm thunderstorms on the fractality of the cloud environment is shown. The data obtained confirm that the electrophysical processes occurring in warm thunderstorms are closely related to the fractal parameter of the medium itself. [ABSTRACT FROM AUTHOR]

The paper presents the results of studies of the characteristics of ultrawideband radiation when a combined antenna is excited by 500 and 200 ps duration bipolar pulses. The combined antenna with dimensions of 60×65×55 mm3 (width×height× length) is optimized in numerical calculations as an array element of a hybrid antenna for radiation of high-power bipolar pulses with a duration of 500 ps. The antenna can also be used to radiate high-power bipolar pulses with duration of 200 ps. The antenna efficiency by the peak electric field strength and the energy efficiency reach 0.8 and 0.9, respectively. [ABSTRACT FROM AUTHOR]

The paper presents the results of investigation of bridging phenomenon occurring at opening of electrical contacts. The mathematical model describing the dynamics of metal molten bridge takes into account the Thomson effect. It is based on the system of partial differential equations for temperature and electrical fields of the bridge in the domain containing two moving unknown boundaries. One of them is an interface between liquid and solid zones of the bridge and should be found by the solution of the corresponding Stefan problem. The second free boundary corresponds to the shape of the visible part of a bridge. Its definition is an inverse problem, for which solution it is necessary to find minimum of the energy consuming for the formation of the shape of a quasi-stationary bridge. Three components of this energy, namely surface tension, pinch effect and gravitation, are defined by the functional which minimum gives the required shape of the bridge. The solution of corresponding variation problem is found by the reduction of the problem to the solution of the system of ordinary differential equations. Calculated values of the voltage of the bridge rupture for various metals are in a good agreement with the experimental data. The criteria responsible for the mechanism of molten bridge rupture are introduced in the paper. [ABSTRACT FROM AUTHOR]

The electric communication technology is gradually mature. With the technological breakthrough of Huawei, a Chinese science and technology enterprise, 5g technology has been gradually developed and popularized for commercial use in China. The 5g era of high speed, low delay and promoting the interconnection of all things is coming as promised. Technological innovation in the field of electric communication is also one of the standards to measure the national scientific and technological innovation ability. In order to seize this potential communication market and improve China's comprehensive competitiveness, China has continuously provided resources and platforms for scientific and technological enterprises to carry out industry university research cooperation. Taking Huawei as an example, this paper explores the innovation strategy behind the technological achievements in communication field from the perspective of industry university research collaborative innovation network, which has reference significance for other enterprises to optimize alliance network and realize efficient R & D. Not only that, the patent database is constantly improving and mature, patent measurement to a certain extent can deeply understand the technological innovation of enterprises, and it has great practical value and social significance to carry out patent Measurement Research on leading enterprises. Based on the patent perspective, through the analysis of applicants and inventors, this paper will deeply analyze Huawei's industry university research cooperation network with universities in the field of electric communication, explore its innovation strategy, summarize the characteristics of its innovation network, and put forward development suggestions for reference according to its shortcomings. [ABSTRACT FROM AUTHOR]

In this paper, the overall objective is to investigate a method to calculate the so-called equivalent surface currents, arisen from an incoming high frequency plane wave, on a long and slightly curved cylindrical conductor, such as a wire. One application for this calculation method is the study of how radar waves are affected by wires mounted near a radar antenna. The paper also includes a brief discussion on how this surface current can be used to calculate the scattered electric field from the conductor. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

This paper describes a finite element method based on electric field distribution for evaluating the electrical performance of an 11 kV high voltage transmission line glass insulator. Glass insulators on wet polluted surfaces were considered. For simulation purposes, the proposed two-dimensional model was designed using AutoCAD software in 2D. Numerical analysis was used to determine the electric field distribution along the glass insulator surface using COMSOL Multiphysics software. It has been shown that a wet polluted surface of a glass insulator has a significant influence on the value of the electric field in the area near the high-voltage end termination. [ABSTRACT FROM AUTHOR]

This paper describes the electrical performance of an 11 kV high voltage transmission line glass insulator. The proposed two-dimensional model was designed using AutoCAD software in 2D. Glass insulator close to dry clean surfaces was considered. The behaviour of the electric field distribution along the creepage distance of a glass insulator under clean surface conditions was analysed using COMSOL Multiphysics software. The results show that the intensity of the electric field stress occurs near the end fitting parts and at a small radius of curvature. The electric field stress is not observed at the top of the glass insulator and at the end of the outer skirt. The strongest electric field strength is near the triple junction region (air-cap-glass) compared to the high-voltage-end terminal region. [ABSTRACT FROM AUTHOR]

Weakly electric fish sense their surroundings in complete darkness by their active electric field detection system. However, due to the insufficient detection capacity of the electric field, the detection distance is not enough, and the detection accuracy is not high. In this paper, a method of underwater detection based on rotating current field theory is proposed to improve the performance of underwater electric field detection system. First of all, we built underwater detection system based on the theory of the spin current field mathematical model with the help of the results of previous researchers. Then we completed the principle prototype and finished the metal objects in the water environment detection experiments, laid the foundation for the further experiments. [ABSTRACT FROM AUTHOR]

In order to understand the distribution of electric field in the space above the train roof accurately and select the installation position of the detection device reasonably, in this paper, the 3D model of pantograph-catenary is established by using SolidWorks software, and the spatial electric field distribution of pantograph-catenary model is simulated based on Comsol software. According to the electric field intensity analysis within the 0.4m space above train roof, we give a reasonable installation of the detection device. [ABSTRACT FROM AUTHOR]

In this paper we outline the main quantum properties of the system of nano-based laser called Dipole Nano-Laser emphasizing mainly on its ability to produce coherent light and for different configurations such as different embedding materials and subjecting it to an external classical electric field. [ABSTRACT FROM AUTHOR]

In this paper, multilevel fuzzy analysis method is used to making a comprehensive evaluation on the health hazards of workers exposed to electric field in 500kV substation. The five different regions of 500kV substation is identified as the first level index, according to the specific measurement substation of each area to set up the second level index. The first level weight is established according to the proportion of the retention time of the workers in the different areas, and the weight of the second level is determined according to the proportion of the measuring points. Establishing five comment sets, and carrying out the fuzzy comprehensive evaluation according to the maximum membership principle, eventually come to the conclusion: although the measured data show that a small number of electric field intensity exposure value of 500kV substation beyond the requirements of the International Commission on non-ionizing radiation protection (ICNIRP) and the requirements of the People's Republic of China(PRC), but workers have very little contact time, therefore, it cannot be explained that there is a large occupational health hazard in 500kV substation. The multilevel fuzzy analysis method can be used to evaluate the health hazards of the electric field in the substation working environment well, it avoids the subjective and limitations of the traditional methods, and can be able to make a more accurate and objective judgment of the substation [ABSTRACT FROM AUTHOR]

The paper treats the steady, laminar flow of magnetohydrodynamic viscous fluid through a slot between fixed curvilinear surfaces of revolution having a common axis of symmetry. The boundary layer are expressed in terms of the intrinsic curvilinear coordinate system. x Θ y. The method of perturbation is used to solve the boundary layer equations. As a result, the formulae for parameters of the flow i.e. the velocity components and pressure are obtained. [ABSTRACT FROM AUTHOR]

The update of the particle momentum in an electromagnetic simulation typically employs the Boris scheme, which has the advantage that the magnetic field strictly performs no work on the particle. In an extreme field, however, it is found that onerously small time steps are required to maintain accuracy. One reason for this is that the operator splitting scheme fails. In particular, even if the electric field impulse and magnetic field rotation are computed exactly, a large error remains. The problem can be analyzed for the case of constant, but arbitrarily polarized and independent electric and magnetic fields. The error can be expressed in terms of exponentials of nested commutators of the generators of boosts and rotations. To second order in the field, the Boris scheme causes the error to vanish, but to third order in the field, there is an error that has to be controlled by decreasing the time step. This paper introduces a scheme that avoids this problem entirely, while respecting the property that magnetic fields cannot change the particle energy. [ABSTRACT FROM AUTHOR]

This is the first time the electric field energy has been captured from Iraq's national grid's 132kV high-voltage transmission lines (HVTL). For harvesting the discharging current of line capacitive electric field energy, a square conductor plate is inserted between the power lines and the ground. The rectified charged voltage between the conductor plate and the ground surface is stored in a storage capacitor, which is used to store the collected electric energy. A low-power comparator is used in a power management circuit to harvest the stored energy. The circuit functions autonomously in response to the amount of stored energy. The experimental findings obtained under the real three-phase 132kV HVTL demonstrate that the linked capacitor charges quickly, indicating that it might be utilized to power low-power consumption equipment. With its simplicity, resilience, and cheap cost, the non-contact energy harvesting device proposed here is predicted to be extensively employed in power transmission, distribution, and grid monitoring applications shortly. [ABSTRACT FROM AUTHOR]

Conductance sensor array is widely used in measuring two-phase flow parameters, in this paper we propose a new configuration of conductance sensors with six rectangular electrodes of same size from the pipe facing to an inner ring-type electrode and use it to measure gas cross-sectional-averaged water holdup value. The designed six rectangular electrodes are axially flush-mounted on the inside wall of an insulating duct. The geometry of six electrodes conductance sensor was determined with finite element numerical analysis. Sensor optimization of the electric field such as uniformity, spatial sensitivity is proposed. This configuration can improve measurement accuracy, through analyze sensitivity distribution, the role of soft field is discussed, and acquired the final size of the electrodes in the end. The simulation results were obtained from COMSOL Multiphysics finite element software. [ABSTRACT FROM AUTHOR]

The effects of electric field on the carrier motion and drift velocity in nanowire (NW) are presented in this paper. When the electric field is applied in NW, the electron is expected to move in anti-parallel direction to the electric field. This is so-called randomness motion is transformed into streamlined motion in extremely high electric field. The normalized Fermi energy and relative electron population as a function of electric field are examined for various degeneracies. It was found that the electric field has lesser influence on the relative electron population with the increased degeneracy. The drift velocity in NW is shown to increase with electric field until it reaches the saturation velocity. Two approximations have been made to simplify the theoretical equation. It is also shown in this paper that when the quantum emission is taken into account, the drift and saturation velocity degrades. [ABSTRACT FROM AUTHOR]

An intermediate E&M course (i.e. based on Griffiths [1]) involves the extensive integration of vector calculus concepts and notation with abstract physics concepts like field and potential. We hope that students take what they have learned in their math courses and apply it to help represent and make sense of the physics. To assess how well students are able to do this integration and application I have developed several simple concept tests on position and unit vectors in non-Cartesian coordinate systems as they are used in intermediate E&M. In this paper I describe one of these concept tests and present results that show both undergraduate physics majors and physics graduate students have difficulty using spherical unit vectors to write position vectors in 3-d space. [ABSTRACT FROM AUTHOR]

This third of three papers explores the possibility of swift, stress-less system transitions between slower-than-light and faster-than-light speeds with negligible net expenditure of system energetics. The previous papers derived a realm of higher dimensionality than 4-D spacetime that enabled such unlabored motion; and showed that fields that could propel and guide systems on unlabored paths in the higher dimensional realm must be fields that have been conditioned to SU(2) (or higher) Lie group symmetry. This paper shows that the system’s surrounding vacuum dielectric [variant_greek_epsilon]μ, within the higher dimensional realm’s is a vector (not scalar) quantity with fixed magnitude [variant_greek_epsilon]0μ0 and changing direction within the realm with changing system speed. Thus, [variant_greek_epsilon]μ generated by the system’s EM field must remain tuned to vacuum [variant_greek_epsilon]0μ0 in both magnitude and direction during swift, unlabored system transitions between slower and faster than light speeds. As a result, the system’s changing path and speed is such that the magnitude of the higher dimensional realm’s [variant_greek_epsilon]0μ0 is not disturbed. And it is shown that a system’s flight trajectories associated with its swift, unlabored transitions between zero and infinite speed can be represented by curved paths traced-out within the higher dimensional realm. [ABSTRACT FROM AUTHOR]

In this paper, we report the electrate properties of ferroelectric polymer PVDF and its composites with three different fillers as ceramic-BaTiO3, metallic semiconductor-ZnO and metallic-TiO2 in PVDF matrix. Each type of PVDF composites thin films with 2wt%, 6wt% and 10wt% of fillers were synthesized by solution casting techniques using dimethylformamide (DMF) as solvent. The XRD pattern confirms the formation of tetragonal perovskite structure of ferroelectric retaining 13-phase and shows proper mixing of fillers interstitially and improved crystallinity with increase of composition in the PVDF matrix. Electric poling effect on the pristine PVDF and its composites were studied by measuring the relative change in strain capacitance using LCR meter. The PVDF and its composites have shown systematic oscillations in strain capacitance with applied electric field. The variation in the strain capacitance is explained in terms of dynamics of dipole pinning and electrostriction induced strain capacitance. [ABSTRACT FROM AUTHOR]

This paper presents a difference type of wavelet transform de-noising technique based on measured lightning electric field. The lightning electric fields captured by two parallel plats sensor and the signal were analyses accordingly. In engineering application, lightning stroke current parameter will relate with electric fields and these parameters can be recognized by direct and in-direct measuring method. Therefore, measuring lightning electric fields (LEF) using parallel plate was done by many researchers. However, measuring LEF has many disturbances such as noise from other apparatus and other device. Therefore, de-noising of LEF signal is important to get useful signal for further research. For this reason, the Centre for Electromagnetic and Lighting Protection Research (CELP) group has been working on a research program to study and characteristic lightning using de-noising technique in order to process and analyse the radiated LEF produced during flash happens. Only three types of wavelet transform are selected and there are Daubechies, Symlets and Coiflets wavelet. The result will be discussed and the best will be selected based on the measured signal. [ABSTRACT FROM AUTHOR]

The electron accelerator ELV6 is used as a heat source for the synthesis of nanoscale powders. The system for releasing the beam into the atmosphere allows vaporizing substances at atmospheric pressure, which makes it possible not only to increase the performance of removing nanoparticles from the reactor, but also allows using the carrier gas as one of the reagents in the process of particle synthesis. This paper describes the reactions that occur with the vaporized substance under conditions of high temperatures, radiation and electric fields. [ABSTRACT FROM AUTHOR]

The hexagonal single quantum well fabricated using the nitride semiconductor heterostructures GaN/InGaN/GaN contains a built-in electric field as a result of lattice strain in this wurtzite structure. By analytic Airy function approach the eigenstates of the quantum well (QW) are obtained under applied electric field. In this paper we report a study on spontaneous and piezoelectric polarization in GaN/InGaN/GaN QW. The analytical expression for third order optical nonlinearities are evaluated by using density matrix approach. We observed that the third-order nonlinearties are blue shifted since intersub and energy spacing increase with increasing applied field strength. The results also showed that both the strong built-in field and external applied electric field have great influence on the optical properties. [ABSTRACT FROM AUTHOR]

Hybrid Energy Storage Systems (HESS) have been gaining prominence in the research field of Electric Vehicles (EVs). The progress of Energy Management Scheme (EMS) is a decisive issue with considerable impact on the EV range and capabilities. In this paper, complementary characteristics of batteries and supercapacitors can be productively used in HESS for a PMSM driven EV application. The usage of HESS in EVs provides many merits such as better regenerative braking, improved vehicle acceleration, reduction in battery stress and improved battery safety. During regenerative braking, the PMSM functions as generator and kinetic energy of EV is utilized by the supercapacitor using proper switching pattern of the inverter. This harvested energy improves vehicle acceleration and keeps the battery from deep discharging during peak power demands where a Fuzzy Logic Controller (FLC) provides the necessary braking force distribution. The performance of the proposed system has been analyzed through simulation using MATLAB/Simulink package for different operating conditions. In hardware, dsPIC is used to provide switching pulse control pattern. The experimental result shows the effectiveness of the proposed coupled EMS. [ABSTRACT FROM AUTHOR]

Study of low frequency emission waves in the Jupiter’s magnetosphere reveals the information about its unique features and these features have influences on Jupiter’s structure and its dynamics. The calculations have been done to explain the radio emissions observed in the Jovian magnetosphere by wave-particle interaction mechanism between the electron-cyclotron waves propagating oblique to the Jupiter’s magnetic field lines. The dispersion relation has been fully derived by the method of characteristic solutions and kinetic approach has been used to derive growth rate in detail for oblique propagating EMEC waves for ring distribution in the presence of parallel AC electric field in anisotropic plasma at 17 RJ. In this paper, variation of various plasma parameters like AC frequency, temperature anisotropy, relativistic factor etc., have been discussed. Effect on growth rate by varying these plasma parameters has been studied. [ABSTRACT FROM AUTHOR]

The emergence of higher-dose and lower-energy halo and source-drain extension implants for 90 and 65-nm nodes drove the design of Axcelis’ Optima MD ion implanter. The Optima MD extends the proven process performance of traditional medium-current implanters over an energy range of 1 keV to 250 keV for singly-charged ion species with beam currents ranging from 1 pμA to 4800 pμA. The Optima MD comprises a hybrid-scan beamline architecture, a new endstation, and a new control system that offers the user more flexibility in data acquisition and statistical process control. The beamline has the capability to provide milliamp beam currents in the low energy (<5 keV) range. The use of an aggressive final deceleration (decel) in combination with a final angular energy filter (AEF) enables this productivity improvement of higher beam currents while mitigating the risk of energy contamination. In this paper the new beam transport system that reduces space charge blowup and maintains focus control at low energies is described. Energy purity is quantified with SIMS analysis in several implants using comparisons with pure drift implants. For the most aggressive decel ratios with low energy beams, energy contamination remains below present detection limits. The system can be configured to process either 200-mm or 300-mm wafers with full 300-mm factory automation capability. This paper describes the system-level characteristics and performance parameters of the Optima MD. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Time-efficient calculations of radiated electromagnetic fields are desirable in many antenna applications. The specific problem analyzed in this paper concerns the development of antenna radomes. To find the optimal configuration, a large number of simulations of virtual antennas with small changes are required. A fast and reliable calculation method is needed for such simulations. In this paper we study the possibility to calculate the far-field with the Discrete Fourier Transform, which enables usage of the Fast Fourier Transform algorithm. An accurate and unique representation of the far-field with this method requires special attention of the sampling interval of the current distribution. Our experience is that this Fourier method is about one thousand times faster than standard practise in industry. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Aerospace, automobile, structural and biomedical engineering applications require strong and smart materials to minimize the weight and vibrations and maximize the strength to achieve an efficient dynamic response and economic advantages. These materials are usually synthesized using poorly conducting plasma in the presence of a strong electric field. This strong applied electric field produces instabilities known as Electrohydrodynamic instability in a poorly conducting parallel flow of plasma. These instabilities produce impurities in the manufacture of strong smart materials. Therefore to manufacture these materials free from impurities there is a need to know whether this external constraint of electric field either suppress or augments these electrohydrodynamic instabilities. This can be achieved by investigating Electrohydrodynamic stability in the presence of an external constraint of strong electric field. The study of this instability is the main objective of this paper. In this paper, stability of poorly conducting parallel plasma in a rectangular channel is studied in the presence of strong electric field subject to linear stability analysis. The basic flow is a function of electric potential and we found that this potential difference also drives the flow in addition to plasma pressure gradient. The condition for the onset of stability is determined in terms of Electric Reynolds Number using both moment and energy methods combined with Galerkin technique. If the motion is unstable an upperbound for the amplification factor is given. From this analysis we conclude that a proper choice of Electric Reynolds number controls instability of a parallel poorly conducting plasma. This result is useful in the manufacture of strong and smart materials free from impurities. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

High electric fields (≥ 0.1 kV/mm) are required to drive a class of the bending mode actuators for shape control and vibration control at various places. The static displacement of piezoelectric ceramic actuator under high electric field in bending mode is studied in this paper. Piezo actuated cantilever beam is fabricated and tip deflection with applied electric field is measured using confocal displacement sensor. Piezoelectric actuator is made of lead zirconate titanate (PZT-5H) ceramics. Finite element methods (FEM) based analysis of piezo actuated cantilever beam is done in COMSOL Multiphysics using linear constitutive equation of piezoelectricity. FEM results of piezo actuated cantilever beam are compared with the experimental results. The static displacement obtained from the experiments deviate from simulation results as the applied electric field increases. The deviation of experimental result from simulation results is approximately 20% at 0.85 kV/mm electric field. [ABSTRACT FROM AUTHOR]

The paper deals with the conditions for extraction and freezing of asperities in the form of Taylor cones from the metallic surfaces under the action of pulsed electric discharge machining. It is demonstrated that due to the presence of strong electric fields (greater than 108 V/m) generated by the presence of anode and cathode spots and under the simultaneous action of weight forces, as well as those of surface tension on the surface of the liquid metal, it develops disturbances and propagates capillary waves. As a result, conical asperities are extracted from the surface, with the top angle of 900. In the case of sudden cooling, these can be frozen in this state. A singular or multiple asperities simultaneous in the shape of Taylor cones can be obtained by solitary electrical discharges under certain energy and time conditions. [ABSTRACT FROM AUTHOR]

Hydrogen molecular ions, due to their simple structure, give the possibility of precise theoretical evaluation of their spectrum and transitions. These ions are shown to be of metrological relevance. In previous study, the intensity of laser-induced electric quadrupole transitions between arbitrary Zeeman split components of H+ 2 . The matrix elements of the electric quadrupole operator are calculated with non-relativistic wavefunctions obtained in the variational approach. In comparison with earlier results on this topic, in our work we use non-relativistic variational wavefunctions for the deuterium molecular ion and this paper includes electric quadrupole matrix elements for higher vibrational states up to ν = 10. [ABSTRACT FROM AUTHOR]+ 2 . The matrix elements of the electric quadrupole operator are calculated with non-relativistic wavefunctions obtained in the variational approach. In comparison with earlier results on this topic, in our work we use non-relativistic variational wavefunctions for the deuterium molecular ion and this paper includes electric quadrupole matrix elements for higher vibrational states up to ν = 10. [ABSTRACT FROM AUTHOR]