Investigation of Electrical Parameters of Fresh Water and Produced Mixed Injection in High-Salinity Reservoirs

Assuming a reservoir with a typical salt-lake background in the Qaidam Basin as a testbed,in this study the var-iation law of the rock electrical parameters has been determined through water displacement experiments with different salinities.As made evident by the results,the saturation index increases with the degree of water injec-tion.When the salinity of the injected water is lower than 80000 ppm,the resistivity of the rock samplefirst decreases,then it remains almost constant in an intermediate stage,andfinally it grows,thereby giving rise to a‘U’profile behavior.As the salinity decreases,the water saturation corresponding to the inflection point of the resistivity becomes lower,thereby leading to a wider‘U’type range and a higher terminal resistivity.For dif-ferent samples,higher initial resistivity of the sample in the oil-bearing state,and higher resistivity after low-sali-nity water washing are obtained when a thicker lithology is considered.

Experimental Research on Effects of Process Parameters on Servo Scanning 3D Micro Electrical Discharge Machining

Servo scanning 3D micro electrical discharge machining (3D SSMEDM) is a novel and effective method in fabricating complex 3D micro structures with high aspect ratio on conducting materials. In 3D SSMEDM process, the axial wear of tool electrode can be compensated automatically by servo-keeping discharge gap, instead of the traditional methods that depend on experiential models or intermittent compensation. However, the effects of process parameters on 3D SSMEDM have not been reported up until now. In this study, the emphasis is laid on the effects of pulse duration, peak current, machining polarity, track style, track overlap, and scanning velocity on the 3D SSMEDM performances of machining efficiency, processing status, and surface accuracy. A series of experiments were carried out by machining a micro-rectangle cavity (900 μm×600 μm) on doped silicon. The experimental results were obtained as follows. Peak current plays a main role in machining efficiency and surface accuracy. Pulse duration affects obviously the stability of discharge state. The material removal rate of cathode processing is about 3/5 of that of anode processing. Compared with direction-parallel path, contour-parallel path is better in counteracting the lateral wear of tool electrode end. Scanning velocity should be selected moderately to avoid electric arc and short. Track overlap should be slightly less than the radius of tool electrode. In addition, a typical 3D micro structure of eye shape was machined based on the optimized process parameters. These results are beneficial to improve machining stability, accuracy, and efficiency in 3D SSMEDM.

The electrical parameters measurement system for electrotome output based on Labview

An accurate detection of the effective values of electric voltage and current from high frequency power generators is a precondition for the development of smart electrotomes. In this light, an energy detection system based on personal computer (PC) is developed hereby. It senses voltage and current in isolation from generators with transformers, and then the measured values are amplified, filtered, transformed into single-ended signals and converted to RMS. The detected signals are transformed into digital signals through Data Acquisition Card (DAQ) and the data are processed with quadratic fit in Labview. Finally, the controller completes constant power output. The experiment results indicate that the energy detection system can measure the output parameters precisely and the controller can achieve constant power control.

Effects of aging parameters on hardness and electrical conductivity of Cu-Cr-Sn-Zn alloy by artificial neural network

In order to predict and control the properties of Cu-Cr-Sn-Zn alloy,a model of aging processes via an artificial neural network(ANN) method to map the non-linear relationship between parameters of aging process and the hardness and electrical conductivity properties of the Cu-Cr-Sn-Zn alloy was set up.The results show that the ANN model is a very useful and accurate tool for the property analysis and prediction of aging Cu-Cr-Sn-Zn alloy.Aged at 470-510 ℃ for 4-1 h,the optimal combinations of hardness 110-117(HV) and electrical conductivity 40.6-37.7 S/m are available respectively.

Electrical Parameters of the Vacuum Vessel in HT-7U Tokamak

A method is presented to express the electrical parameters of the vacuum vessel in this paper. According to the results of numerical computation and the distribution of the eddy currents, the mutual inductance can be given by calculating the flux produced by the toroidal eddy currents. The time constants of the vacuum vessel of HT-7U tokamak are derived from the decay characteristics of the eddy currents.

Influence of electrical parameters on H2O2 generation in DBD non-thermal reactor with water mist

A dielectric barrier discharge（DBD） reactor is introduced to generate H2O2 by non-thermal plasma with a mixture of oxygen and water mist produced by an ultrasonic atomizer.The results of our experiment show that the energy yield and concentration of the generated H2O2 in the pulsed discharge are much higher than that in AC discharge,due to its high energy efficiency and low heating effect.Micron-sized liquid droplets produced by an ultrasonic atomizer in water mist have large specific surface area,which greatly reduces mass transfer resistance between hydroxyl radicals and water liquids,leading to higher energy yield and H2O2 concentration than in our previous research.The influence of applied voltage,discharge frequency,and environmental temperature on the generated H2O2 is discussed in detail from the viewpoint of the DBD mechanism.The H2O2 concentration of 30 mg l^-1,with the energy yield of 2 gkW^-1h^-1 is obtained by pulsed discharge in our research.

Electrical model parameters identification of radiofrequency discharge in argon through 1D3V/PIC-MC model

This work represents a contribution to the modeling of a radiofrequency（RF） discharge in argon at low pressure（from 25 to 200 mTorr）.It is started by the validation of the collision cross sections used in the particle model through a comparison between the transport coefficients calculated by these data and the measurements of the transport coefficients already exist in the literature,the particle model is also validated by a comparison between the calculated plasma density and that measured in the literature.The electrical model proposed in this work consists of replacing the RF discharge by a passive circuit（resistance in series with a capacitor）,where the resistance represents the plasma medium and the obstruction of the passage of the electronic current,and the capacitor represents the sheaths and the appearance of the displacement current in these regions.The parameters of the electrical model are obtained through particle modeling.The electrical model presented accurately reproduces the current of the discharge,but without considering the phenomenon of distortion.The total harmonic distortion rate follows the variation of the plasma density;its maximum value is 5.75% at 100 mTorr.

Investigation of radiation influences on electrical parameters of 4H-SiC VDMOS

The radiation influences on electrical parameters of4H-SiC vertical double-implanted metal-oxide-semiconductor field effect transistor( VDMOS) are studied. By simulations on SRIM software and SILVACO software, the electrical parameters shifts of the device with defects in different regions are observed. The results indicate that the defects in different regions induced by radiations lead to different degradations of the electrical parameters. Non-ionization bulk defects in the JFET region make the drain-source on-state resistance Rdson increase,and those near the impact ionization center make the breakdown voltage Vbreakdownincrease. Moreover,the radiationinduced SiC/SiO2 interface defects,known as negative interface charges or positive interface charges,influence the electrical parameters significantly as well. The positive interface charges along the SiC/SiO2 interface above the channel region lead to a decrease in threshold voltage Vth,Rdsonand Vbreakdown,while positive interface charges along the Si C/Metal interface above the main junction of the terminal only leads to the decrease in Vbreakdown. The negative interface charges along the SiC/SiO2 interface above the channel region can make Vth,Rdsonand Vbreakdownincrease.

Effects of the Shading Rate on the Electrical Parameters of CIGS-Based Solar Modules

The aim of this article is to study the effects of the shading rate on the electrical performance parameters of CIGS PV modules. The study concerns a new flexible CIGS type photovoltaic module with a power of 90 W, manufactured by the company Shenzhen Shine Solar Co., Ltd. This module, reference SN-CIGS90, is tested under the initial conditions to ensure its correct operation and to determine the initial values of the electrical parameters before shading. After this characterization test, the module is exposed under the actual operating conditions of the Renewable Energies Study and Research Center (CERER), located in Dakar, then 4 types of shading are performed with the same mask: partial shading 25% partial shading, 50% partial shading, 75% partial shading, and 100% full shading. The variation rates obtained on the experimental values of the 4 types of shading carried out determine that the shading phenomenon constitutes a factor that influences negatively on the electrical parameters of a CIGS-based PV module. Indeed, for 25% of the surface of the shaded module, there is a reduction of 58.139% of the maximum power and of 60.507% of the efficiency and for shading of 100%, the module loses 84.436% of its maximum power and 84.135% of its performance.

Dynamical modelling of cardiac electrical activity using bidomain approach: The effects of variation of ionic model parameters

This work presents the dynamical modelling of cardiac electrical activity using bidomain approach. It focuses on the effects of variation of the ionic model parameters on cardiac wave propagation. Cardiac electrical activity is governed by partial differential equations coupled to a system of ordinary differential equations. Numerical simulation of these equations is computationally expensive due to their non-linearity and stiffness. Nevertheless, we adopted the bidomain model due to its ability to reflect the actual cardiac wave propagation. The derived bidomain equations coupled with FitzHugh-Nagumo’s ionic equations were time-discretized using explicit forward Euler method and space-discretized using 2-D network modelling to obtain linearized equations for transmembrane potential Vm, extracellular potential φe and gating variable w. We implemented the discretized model and performed simulation experiments to study the effects of variation of ionic model parameters on the propagation of electrical wave across the cardiac tissue. Time characteristic of transmembrane potential, Vm, in the normal cardiac tissue was obtained by setting the values of ionic model parameters to 0.2, 0.2, 0.7 and 0.8 for excitation rate constant ε1, recovery rate constant ε2, recovery decay constant γ and excitation decay constant β respectively. Changing the values of ε1, ε2 to 0.04 and 0.28 respectively, the obtained Vm showed a time dilation at 0.04 indicating cardiac arrhythmia but no significant change to Vm was observed at 0.28. Also, changing β to 0.3 and 1.1 and γ to 0.4 and 1.2 sequentially, there was no significant change to the time characteristic of Vm. The obtained results revealed that only decrease in ε1, ε2 impacted significantly on the cardiac wave propagation.

Uniformity of Electrical Parameters on MCT Epitaxy Film

For Hall measurement under different magnetic fields at LN2 temperature,Hg1-xCdxTe （MCT） film （radius 1 cm） grown on CdTe substrate by LPE is photoengraved into many small Van Der Pauw squares,then their Hall coefficients and mobilities are measured and analyzed,respectively.Two films were Hall-tested during the temperature range from LHe 4.2 K to about 200 K.An actual impression on the uniformity of electrical parameters for MCT film can obtained by means of the methods presented in this paper.

The Electrical Parameters Modeling and Experimentation of Copper Vapor Laser

In this paper, the present developments of copper vapor laser technology were computational modeling and simulations methods. In most of the cases, before the experiment, the functions of electrical parameters can be predicted by the use of physical simulation codes. A single simulation model describing the discharge circuitry was introduced. By solving the equations of circuit via Runge-Kutta method, the current and voltage pulses of the discharge tube were investigated, which are in good agreement with the experimental results of the same laser.

Characterization of Subsurface Lithology and Aquifer Parameters Using Vertical Electrical Sounding(VES)for Groundwater Development in Igbo-Imabana,Southern Nigeria

Vertical Electrical Soundings(VES)using Schlumberger array was carried out at fifteen(15)different points to evaluate aquifer characteristics within Igbo-Imabana,Abi L.G.A of Cross River State.Resistivity meter and its accessories were used for data acquisition.The maximum current and potential electrode distance were 400 m and 20 m respectively.The field data were interpreted using Interpex software and three to five geo-electric layers encountered within the study area.The dominant curve type was H followed by K.From the result,geo-electric layers delineated were sandstone,clay,saturated sandstone,sandy shale,clayey shale,and shale with average apparent resistivity values of 2249.94Ωm,2.86Ωm,365.28Ωm,222.69Ωm,14.60Ωm and 59.02Ωm respectively.The top geoelectric layer was dominantly lateritic topsoil,with variation in degrees of compaction and having an average resistivity of 876.33Ωm with depth and thickness generally less than 5 m.The calculated aquifer parameters hydraulic conductivity(K_(c)),transmissivity,longitudinal conductance,and transverse resistance from the VES results show ranges values;3.86×10^(-4)to 4.69×10^(-2)m/day,2.95×10^(-3)to 2.82 m^(2)/day,2.95×10^(-3)to 2.81Ωm and 484.33 to 19444.83Ω^(2)m respectively.The aquifer thickness and depth values range from 3.60 m to 68.05 m and 5.20 m to 76 m respectively.The study reviewed that the area is made of heterolithic/heterogenous lithofacies,confined aquifer(s),shallow and deep aquifer.Also,from the models and aquifer parameters,the area is characterized by semipervious materials.This integrally explains why the area have have low transmissivity and majority of boreholes drilled in the area failed.

Effects of preparation parameters on growth and properties of β-Ga_(2)O_(3) film

The Ga_(2)O_(3) films are deposited on the Si and quartz substrates by magnetron sputtering, and annealing. The effects of preparation parameters(such as argon–oxygen flow ratio, sputtering power, sputtering time and annealing temperature)on the growth and properties(e.g., surface morphology, crystal structure, optical and electrical properties of the films) are studied by x-ray diffractometer(XRD), scanning electron microscope(SEM), and ultraviolet-visible spectrophotometer(UV-Vis). The results show that the thickness, crystallization quality and surface roughness of the β-Ga_(2)O_(3) film are influenced by those parameters. All β-Ga_(2)O_(3) films show good optical properties. Moreover, the value of bandgap increases with the enlarge of the percentage of oxygen increasing, and decreases with the increase of sputtering power and annealing temperature, indicating that the bandgap is related to the quality of the film and affected by the number of oxygen vacancy defects. The I–V curves show that the Ohmic behavior between metal and β-Ga_(2)O_(3) films is obtained at 900℃. Those results will be helpful for the further research of β-Ga_(2)O_(3) photoelectric semiconductor.

Effects of electric parameters on microstructure and properties of MAO coating fabricated on ZK60 Mg alloy in dual electrolyte

Micro-arc oxidation (MAO) process was carried out in a dual electrolyte system of NaAlO 2 and Na 3 PO 4 on ZK60 Mg alloys to explore the effect of electric parameters including current density, frequency, duty cycle and oxidation time on the evolution of coatings and other characteristics. The microstructural characteristics of coatings were observed by scanning electron microscopy (SEM) combined with the analysis of voltage-time responses during MAO process. Test of weight loss was conducted at a 3.5% NaCl solution to assess the resistance to corrosion. The results indicate that the current density and duty cycle play key roles on the coating quality. The peak voltage during MAO process increased with the increase in current density but the coating would be more easily detached when the current density was beyond a critical value. Voltage during MAO and microstructure of the coating were affected remarkably by duty cycle, and corrosion resistance was improved greatly when duty cycle was 40%. By means of single variable experiments, MAO process with optimized electric parameters was developed, which corresponds to the current density of 20 A dm 2 , frequency of 500 Hz, duty cycle of 40% and oxidation time of 15 min.

A Hydrogeophysical Model of the Relationship between Geoelectric and Hydraulic Parameters, Central Jordan

Geoelectrical soundings using the Schlumberger array were carried out in the vicinity of 23 pumping test sites to determine aquifer parameters, central Jordan. On the basis of aquifer geometry, the area has been di-vided into two hydraulic units: the northern flood plain and the flood plain to its south. Field resistivity data are interpreted in terms of the true resistivity and thickness of subsurface layers. These parameters are then correlated with the available pumping test data. Significant correlations between the transmissivity and modified transverse resistance as well as between the hydraulic conductivity and formation factor were ob-tained for the two hydraulic units, in central Jordan are presented here.

Combined Estimation of Vehicle Dynamic State and Inertial Parameter for Electric Vehicles Based on Dual Central Difference Kalman Filter Method

Distributed drive electric vehicles(DDEVs)possess great advantages in the viewpoint of fuel consumption,environment protection and traffic mobility.Whereas the effects of inertial parameter variation in DDEV control system become much more pronounced due to the drastic reduction of vehicle weights and body size,and inertial parameter has seldom been tackled and systematically estimated.This paper presents a dual central difference Kalman filter(DCDKF)where two Kalman filters run in parallel to simultaneously estimate vehicle different dynamic states and inertial parameters,such as vehicle sideslip angle,vehicle mass,vehicle yaw moment of inertia,the distance from the front axle to centre of gravity.The proposed estimation method only integrates and utilizes real-time measurements of hub torque information and other in-vehicle sensors from standard DDEVs.The four-wheel nonlinear vehicle dynamics estimation model considering payload variations,Pacejka tire model,wheel and motor dynamics model is developed,the observability of the DCDKF observer is analysed and derived via Lie derivative and differential geometry theory.To address system nonlinearities in vehicle dynamics estimation,the DCDKF and dual extended Kalman filter(DEKF)are also investigated and compared.Simulation with various maneuvers are carried out to verify the effectiveness of the proposed method using Matlab/Simulink-CarsimR.The results show that the proposed DCDKF method can effectively estimate vehicle dynamic states and inertial parameters despite the existence of payload variations and variable driving conditions.This research provides a boot-strapping procedure which can performs optimal estimation to estimate simultaneously vehicle system state and inertial parameter with high accuracy and real-time ability.

Parameters matching and optimization of parallel hybrid electric vehicle powertrain

Aiming at the development of parallel hybrid electric vehicle （PHEV） powertrain, parameter matching and optimization are presented, According to the performance of PHEV, the optimization range of engine, motor, driveline gear ratio and battery parameters are determined. And then a two-level optimization problem is formulated based on analytical target cascading （ATC）. At the system level, the optimization of the whole vehicle fuel economy is carried out, while the tractive performance is defined as the constraints. The optimized parameters are cascaded to the subsystem as the optimization targets. At the subsystem level, the final drive and transmission design are optimized to make the ratios as close to the targets as possible. The optimization result shows that the fuel economy had improved significantly, while the tractive performance maintains the former level.

Identification of dynamic model parameters for lithium-ion batteries used in hybrid electric vehicles

An electrical equivalent circuit model for lithium-ion batteries used for hybrid electric vehicles （HEV） is presented. The model has two RC networks characterizing battery activation and concentration polarization process. The parameters of the model are identified using combined experimental and extended Kalman filter （EKF） recursive methods. The open-circuit voltage and ohmic resistance of the battery are directly measured and calculated from experimental measurements, respectively. The rest of the coupled dynamic parameters, i.e. the RC network parameters, are estimated using the EKF method. Experimental and simulation results are presented to demonstrate the efficacy of the proposed circuit model and parameter identification techniques for simulating battery dynamics.

Effects of electric parameters on corrosion resistance of anodic coatings formed on magnesium alloys

Anodic coatings were obtained by micro-arc oxidation on AZ91HP magnesium alloys in a solution containing 10 g/L NaOH and 8 g/L phytic acid.The effects of electric parameters including frequency,final voltage,duty cycle and current density on the corrosion resistance of anodic coatings formed on the magnesium alloys were investigated by using an orthogonal experiment of four factors with three levels.The results show that the final voltage plays a main role on the coating properties.The orders of affecting corrosion resistance and coating thickness are separately ranked from high to low as,final voltage>duty cycle>current density>frequency and final voltage>current density>frequency>duty cycle.The final voltage influences the corrosion resistance of the anodized samples mainly by changing the surface morphology and coating thickness.