Voltage Rate Research Articles

Adhesion of electron-beam evaporated SiO2/TiO2 anti-reflective coating on ion-treated polycarbonate substrate under xenon arc accelerated weathering test

Anti-reflective (AR) coatings on polymer substrates enhance light transmittance and minimize reflectance loss. However, durability of multi-layered AR coatings on polymer substrates under various weathering conditions (temperature, radiation, and humidity) can be challenging and affecting adhesion of the coating to the substrate. Therefore, in the present work, Xenon arc accelerated weathering test followed ISO 16474 guidelines was used to investigate durability of electron-beam evaporated SiO2/TiO2 stacking layer as the AR coating on an ion-treated polycarbonate (PC) substrate by varying anode voltage of the ion treatment, oxygen flow rate during the treatment, and thickness of a binding layer (Chromium-based alloy) sandwiched between AR coating and PC substrate. Crosshatch tape test based on ASTM D3359 was used to evaluate the adhesion performance. Physical changes of ion-treated PC surface were characterized by atomic force microscopy and scanning electron microscopy, whereas Fourier transform infrared spectroscopy was adopted to identify chemical functional groups on the treated PC surface. Residual stress and optical reflection of AR coating on the PC were measured by laser interferometry and UV–Vis spectrophotometry, respectively. As anode voltage increased with no oxygen flow, average surface roughness of PC increased but the roughness decreased as oxygen flow rate increased when the highest anode voltage (100 V) was applied. A reversed trend of the roughness achieved with the lowest anode voltage (80 V). Amount of C–O functional group on treated PC increased when the average surface roughness decreased. The adhesion improved by incorporating a binding layer, depending on anode voltage and oxygen flow rate, that can alter residual compressive stress of the material system, reduce moisture and UV attack without sacrificing optical performance of the AR coating. Generally, a better AR coating adhesion can be achieved with smoother PC surface having higher amount of C–O bonding, and higher overall residual compressive stress.

SEPIC-Boost-Based Unidirectional PFC Rectifier with Wide Output Voltage Range

A novel unidirectional hybrid PFC rectifier topology based on SEPIC and boost converters is proposed, which is applicable to various industrial applications such as electric vehicle charging stations, variable speed AC drives, and energy storage systems. Compared to other rectifiers, the proposed SEPIC-boost-based rectifier exhibits continuous current on the AC side, lower voltage stress on the active switches, a wider range of DC output voltage, no auxiliary DC-DC converters, and a high step-up static voltage gain operating with low input voltage and a low step-up static gain for the high-input-voltage operation. These traits allow the SEPIC-boost-based rectifier to utilize smaller input-side harmonic filtering inductors and adopt active switches with lower voltage ratings, resulting in reduced conduction losses. Additionally, the proposed rectifier features power factor correction and high boost/buck voltage-gain capabilities, simplifying control for electric vehicle charging and expanding its range of applications. In this paper, the operating principle of the novel topology is presented first, and then the mathematical model of the proposed rectifier is built. Based on this, the comparison between the proposed topology and conventional boost and SEPIC converters is given. Furthermore, the control strategy, including the high-power-factor control and the balancing control to the DC capacitor voltages, is discussed. Finally, to validate the accuracy of the proposed rectifier’s theoretical research, a 500-W SEPIC-boost rectifier system has been constructed in the laboratory, generating a 200/120 Vdc output voltage from a 155 Vpk/50 Hz power source.

Bubble deformation and breakup in a non-uniform electric field

In this paper, the deformation and breakup characteristics of bubbles during their growth in a mixture solution were studied with a needle-ring electrode configuration in the presence of an electric field by using high-speed photography. Four distinct bubble breakup behaviors of the dripping, cone, kink and branch regimes were achieved successfully by manipulating the electric field. By considering the applied voltage and gas flow rate, the cone structure, interface stability, departure frequency and bubble size distribution in different regimes were quantitatively discussed. It is found that the cone height, interface curvature, departure frequency and bubble size distribution are evidently associated with bubble breakup regimes. As the electric field strength increased, the bubbles stretched in the direction of the electric field and the instability of the gas–liquid interface became stronger, which eventually resulted in the bubbles fragmenting into a cluster of microbubbles. This work provides a fundamental understanding of bubble deformation and breakup mechanisms under the electric field.

Study of the thrust response characteristics of Hall Micro Thruster

An advanced Watt class Hall Micro Thruster (HMT) is offered for Space Gravitational Wave Detection (SGWD), and an investigation has been conducted on its start-up, shutdown, rise, and fall response times. The research involved creating a circuit for thruster discharge and signal acquisition, using a Faraday probe to measure the plasma plume signal generated by the thruster, and characterizing the thrust directly. Ultimately the response time of the thruster is extracted from the discharge current and Faraday current signals. The experimental results demonstrate that the HMT has a response time ranging from 1.08 ms to 16.76 ms at mass flow rates of 0.02 mg/s and 0.04 mg/s, meeting the SGWD requirements for micro thruster response time. This research provides a physical foundation and explanation for the variation of HMT response time with discharge voltage versus mass flow rate with several key parameters that affect HMT plasma discharge, such as neutral gas number density (nn) and ionization mean free path (λi). Furthermore, we have examined several anomalies in the signal. Overall, this research provides a brand-new method for measuring the thrust response time of electric thrusters.

Study on the influence of mechanism dispersion on transient recovery voltage distribution of modular DC vacuum circuit breakers

AbstractA simulation analysis and an experiment are carried out to investigate how the gap difference between the breaks of a direct current vacuum circuit breakers with multi‐breaks (MB‐DC VCB) caused by the mechanism dispersion of the breaker influences the distribution of TRV among the breaks. An interruption model of MB‐DC VCB, combining the continuous transition model, is established to analyse the rising rate of transient recovery voltage and the dielectric strength recovery speed of the breaks for MB‐DC VCB under different gap difference conditions. Based on the experimental platform of dual break DC vacuum circuit breaker breaking, the correctness of the simulation model is verified on a DC VCB with the double‐breaks interruption experimental platform. Moreover, a model is applied to the non‐synchronous interruption simulation of a DC VCB with three‐breaks. The relationship between the TRVs of the breaks under different gap difference conditions is analysed using the comparative analysis method, obtaining the maximum gap difference at the moment of breaking failure. The results of this study show that large‐gap breaks have a higher TRV than small‐gap breaks (the fracture of the action delay module), with double fractures reaching 1.4 times and triple fractures reaching a maximum of 1.52 times; the ability of small‐gap breaks to withstand TRV is weak, giving rise to re‐breakdown or even interruption failure; as the number of fractures increases, the maximum gap difference also increases. Improving the synchronous interruption ability of the MB‐DC VCB is conducive to improving the interruption performance and interruption success rate of this type of a circuit breaker.

Research on the characteristics of atmospheric pressure AC argon discharge plasma jet: comprehensive effects of discharge voltage, gas flow rate, and external magnetic field

Atmospheric pressure plasma jet has garnered significant attention for their vast potential across diverse fields, with the discharge conditions playing a pivotal role in shaping their physicochemical properties and ultimately determining their application efficacy. Factors such as discharge voltage, gas flow rate, and the introduction of an external magnetic field intricately influence the performance of plasma jet. The combined effects of any two of these factors can yield enhanced outcomes, while they also introduce complexity to the discharge phenomena. However, there is currently a lack of research on the combined effects of external magnetic field, discharge voltage, and gas flow rate on the characteristics of plasma jets, making it difficult to comprehensively evaluate the discharge characteristics of plasma jet under multiple discharge conditions. Therefore, this paper focuses on an AC excited atmospheric pressure argon plasma jet and investigates the combined effects of external magnetic field, discharge voltage, and gas flow rate on various characteristic parameters of the plasma jet, encompassing macroscopic morphology, discharge power, gas temperature <i>T</i><sub>g</sub>, electron excitation temperature <i>T</i><sub>exc</sub>, electron density <i>n</i><sub>e</sub>, emission intensity of excited state Ar* particles, and number density of ground state ŸOH particles by using methods of camera shooting, and electrical parameter measurement, spectroscopic analysis of emission and absorption spectra. The results show that the effect of discharge voltage on the characteristic parameters of the plasma jet remains consistent, unaffected by variations in gas flow rate or the presence of an external magnetic field; an increase in discharge voltage consistently improve jet performance by enhancing the discharge power, extending the plasma plume length, elevating the gas temperature <i>T</i><sub>g</sub> and electron excitation temperature<i> T</i><sub>exc</sub>, increasing the electron density <i>n</i><sub>e</sub> and emission intensity of excited state Ar* particles, as well as the number density of ground state ŸOH particles. The addition of an external magnetic field can improve the jet performance without significantly changing the discharge power, and the extent of this improvement is influenced by the mode of magnetic field action. Notably, when the magnetic field selectively targets the plasma plume, excluding direct interaction with electrodes discharge area, the enhancement in jet performance is most pronounced. The effect of gas flow rate on jet performance becomes intricate, intertwined with the effects of voltage and the external magnetic field. When an external magnetic field is present, excessive voltage and gas flow rate may reduce the number density of ground state ŸOH particles generated by plasma jet. This underscores the need for a nuanced understanding when optimizing jet performance under multiple discharge conditions. Simply combining the optimal conditions for each individual factor does not guarantee the achievement of peak jet performance when all three discharge conditions act in concert. This study offers valuable insights into the discharge characteristics of plasma jet under varying discharge conditions, providing a guidance for optimizing performance of plasm jet and fostering the advancement of atmospheric pressure plasma jet technology across diverse application domains.

Macroscopic behavior of populations of quadratic integrate-and-fire neurons subject to non-Gaussian white noise.

We study macroscopic behavior of populations of quadratic integrate-and-fire neurons subject to non-Gaussian noises; we argue that these noises must be α-stable whenever they are delta-correlated (white). For the case of additive-in-voltage noise, we derive the governing equation of the dynamics of the characteristic function of the membrane voltage distribution and construct a linear-in-noise perturbation theory. Specifically for the recurrent network with global synaptic coupling, we theoretically calculate the observables: population-mean membrane voltage and firing rate. The theoretical results are underpinned by the results of numerical simulation for homogeneous and heterogeneous populations. The possibility of the generalization of the pseudocumulant approach to the case of a fractional α is examined for both irrational and fractional rational α. This examination seemingly suggests the pseudocumulant approach or its modifications to be employable only for the integer values of α=1 (Cauchy noise) and 2 (Gaussian noise) within the physically meaningful range (0;2]. Remarkably, the analysis for fractional α indirectly revealed that, for the Gaussian noise, the minimal asymptotically rigorous model reduction must involve three pseudocumulants and the two-pseudocumulant model reduction is an artificial approximation. This explains a surprising gain of accuracy for the three-pseudocumulant models as compared to the two-pseudocumulant ones reported in the literature.

Ultralong-lasting plasma-activated water: production and control mechanisms

Despite the rapidly growing interest stemming from the broad-spectrum, high inactivation capacity, and environmental friendliness of the plasma-activated water (PAW), practical applications are limited because of the PAW’s short lifetime. While low-temperature storage can extend the lifetime, but the freezing and thawing processes are energy- and labor-intense and are generally not suitable for large-scale applications such as environmental and biomedical disinfection. This work addresses this issue by developing the ultra-long-life PAW at room temperature. The innovative approach is based on using DC needle-water discharges, wherein the gaseous products are blown out and absorbed separately by a gas flow. By simply adjusting the voltage and gas flow rates, two distinctive types of PAW with acidic hydrogen peroxide and nitrite as the main products are produced and separated in the discharge chamber and gas bubbling chamber. Intentional mixing of these two PAWs causes a chain chemical reaction dominated by peroxynitrite (ONOOH). This reaction can generate a variety of short-lived reactive species, thereby achieving the ultralong-lasting PAW with very stable bactericidal ability. This study further demonstrates the ability to effectively control the reaction products in both chambers and provides insights into the secondary activation mechanism of short-lived reactive species stimulated by ONOOH.

Synergistic low-temperature plasma (DBD) treatment of n-hexane gas

The experiment is based on a single dielectric barrier discharge (DBD) plasma generator, using micro-discharge to produce non-equilibrium plasma synergizing with two different catalysts (TiO2, 4A molecular sieve) to decompose n-hexane gas. In the n-hexane degradation experiment, the study investigates the influence of factors such as the type of catalyst, discharge voltage, and flow rate on the degradation rate of n-hexane. The experiments revealed that in all synergistic experiments with catalysts, the degradation rate of n-hexane increased with the decrease in flow rate and with the increase in voltage. Among the four catalysts selected, the 4A molecular sieve catalyst showed the best removal effect for n-hexane gas, reaching 73.2%.

Drilling of Ti Grade‐2 Alloy Using WC Tool in Micro‐EDM and Its Multiparameter Optimization

In this study, microelectrical discharge machining (μEDM) is used for drilling microholes on a thin sheet of Ti Grade 2 alloy of thickness 50 μm using a tungsten carbide (WC) microtool of diameter 470 μm. The main focus of the study is to understand the electrical and nonelectrical μEDM parameters on the accuracy, precision, and machining efficiency of drilled holes. The controllable process factors such as capacitance, voltage, tool rotation, and feed rate are considered when conducting the experiments based on a Taguchi L16 orthogonal array. The main effect and interaction contour plots have been prepared to investigate the influence of the process parameters on the response measures like material removal rate, overcut, circularity, and taper angle of the drilled holes. Analysis of variance (ANOVA) has been carried out to study the percentage contribution and significance of each process parameter on the performance measures. The micrographic images reveal the quality of the profiles and edges of the drilled holes. Further, the Overall Evaluation Criterion (OEC) is applied for multiparameter optimization.

The Effect of Electric Voltage Variation and Flow Rate on Decreasing Remazol Red Rb 133 Dye Levels in a Continuous Electrocoagulation Process

The usage of synthetic dyes, such as Remazol Red RB 133, benefits the product by boosting its added value, but it also has a negative influence on the aquatic environment when waste water is disposed of directly. As a result, electrocoagulation technology is utilized to lower the levels of Remazol Red RB 133 dye, ensuring that it does not affect the environment. This study seeks to examine the influence of variations in electric voltage (10, 12, 14 volts) and flow rate (80, 100, and 120 mL/minute) on decreasing concentrations of the colorant RB-133 Remazol in the Continuous Electrocoagulation Process. A UV-Vis spectrophotometer will be used to see the dye concentration after the electrocoagulation process and will be analyzed using the adsorption kinetics model and the Langmuir and Freundlich adsorption isotherm models.

Optimal Switching Method Using Variable Additional On-Time Control for CRM-Operated Multicell Series-Parallel Converter

Unlike the conventional boost-derived power-factor-correction (PFC) converter, the multi-cell series-parallel (MCSP) converter can step-up/step-down the output voltage. Its modular concept has a flexibility to select the voltage rating of switches depending on the number of cells. Based on its high degree-of-freedom (DOF) in combination of switching states, this paper proposes an optimal switching method that can suppress the amplitudes of switch currents while improving converter efficiency by synthesizing pentagonal inductor current waveform in critical conduction mode (CRM) control. In addition, a total harmonic distortion of input current (iTHD) is improved with variable additional on-time control. Thanks to an inherent capacitor voltage balancing feature of the MCSP converter, it does not require additional balancing control. The feasibility of the proposed control is verified by experiments in the 300 W prototype.

Intelligent agents for advanced power system protection schemes

This study explores the incorporation of intelligent agents to improve power system safety, using several computational models including machine learning, rule-based systems, neural networks, and fuzzy logic. The research assesses the effectiveness and efficiency of these agents in promptly identifying, categorizing, and responding to faults in the power system architecture using empirical analysis. The results demonstrate the higher performance of agents based on neural networks, with an average improvement in fault prediction accuracy of 38% compared to systems based on rules. Furthermore, the evaluation of power system devices demonstrates a direct relationship between greater voltage ratings and increased expenses for both installation and maintenance, underscoring their crucial importance within the system. An examination of fault severity reveals that greater severity failures have a direct and significant influence on system downtime. These problems lead to longer interruptions, which emphasizes the need of implementing effective fault management systems. Intelligent agents' actions have different costs and reaction times. Actions based on neural networks have lower average costs and shorter response times, demonstrating their cost-effectiveness and efficiency in addressing faults. The study of percentage change highlights the importance of using various kinds of intelligent agents and higher-rated devices. This research offers insights into performance differences and the consequences for optimizing protection measures. This research provides a thorough understanding of how intelligent agents may enhance power system protection. It also offers guidance for future improvements in creating power grid infrastructures that are robust, dependable, and adaptable.

A Three-Transistor Energy Management Circuit for Energy-Harvesting-Powered IoT Devices

Energy harvesting (EH) provides a promising solution for powering distributed Internet of Things (IoT) devices. Due to the low-level and sporadic ambient energy supply, an EH-powered device should operate in an intermittent and energy-driven mode. Commercial voltage supervisors were not optimized for the EH scenario, making it difficult to satisfy all new demands. The conventional energy management (EM) circuit has a risk of locking up during the turn-on transient; therefore, it might fail to power the IoT load device. Previous technologies have used a relatively large circuit to solve this problem. In this paper, a concise discrete three-transistor energy management circuit (3T-EM) is proposed. It can track stored energy, switch on/off to the load device, and provide a regulated voltage output. These key functions are realized by utilizing a minimum number of components; therefore, power consumption and manufacturing cost are largely cut. The voltage thresholds and minimum input current are theoretically derived. In experiments, the on/off thresholds can be adjusted accurately, as predicted by the theory. The 3T-EM circuit can ensure the correct operation when the input current is as low as 0.4 μA. Control experiments also prove the effectiveness and performance of the 3T-EM circuit. The proposed 3T-EM circuit shows the characteristics of low cost, low power, inherent regulation, high voltage rating, and good predictability. It is a good candidate to perform the EM task in widely distributed EH-powered IoT devices.

Solid State Pulsed Power Modulator With High Repetition Rate and Short Pulse Width for High-Speed Pulsed Lasers

This paper proposes a modular pulsed power modulator (PPM) with a short pulse width and high repetition rate for pulsed lasers. The presented PPM is based on the modular structure to use semiconductor switches with low voltage ratings since these switches have fast switching speed which is an essential requirement to generate short pulses. In addition, to make a short gate signal which is also needed to generate short pulses, a gate driver circuit which applies positive and negative voltages asymmetrically is proposed. Moreover, a heatsink structure to minimize the parasitic capacitances is presented for the high repetition rate. Furthermore, a DC-DC converter for the modular PPM is developed, which connects transformers in parallel at the primary side to achieve voltage balance without any compensation circuit. Experimental results from a 5 kV PPM with the pulse width below 20 ns and repetition rate of 1 MHz are presented to verify the proposed works.

Impact of Converter Topology on the Shunt Active Power Filter Systems Efficiency

This paper presents the performance of shunt active power filters (Shunt APFs) which can compensate harmonic currents generated by no-linear load based on five and seven-level neural point clamped (NPC) inverters. Multilevel inverters are currently being investigated and used in several industrial applications. Their advantages include the capability to reduce the harmonic content and decrease the voltage or current ratings of the semiconductors. On the other side, fuzzy techniques are successfully employed in various industrial applications; they represent a good alternative to traditional control systems. To benefit of all these advantages an efficient control scheme for five and seven-level Shunt APF based on multi-carrier pulse width modulation (MC-PWM) and fuzzy control approaches are adopted in this work. The fuzzy controller is designed to improve compensation capability of shunt APF by adjusting the error using a fuzzy rule. The control strategy to identify the current reference uses synchronous detection method (SMD), this technique is easy to implement and achieves good performances. The numerical simulation results carried with MATLAB-Simulink and SimPowerSystems Toolbox show the effectiveness of the proposed systems and confirm the superiority of the seven-level shunt APF compared to five-level configuration system.

Performance optimization and investigation of metal-cored filler wires for high-strength steel during gas metal arc welding

Abstract This study examines the utilization of metal-cored filler wire in conjunction with the gas metal arc welding (GMAW) technique for welding high-strength S690QL steel. Since welding parameters significantly impact the bead quality and weld joint integrity, the main objective was to identify the optimal welding parameters. To achieve this, the input variables including the current (A), voltage (V), and gas flow rate (GFR), and their effects were evaluated for reinforcement (R), width (W), depth of penetration (DOP), and the width of the heat-affected zone (HAZ). For a more efficient and cost-effective investigation, a Box–Behnken design, which is based on response surface methodology, was used for bead-on-plate trials. Mathematical regression models, derived from experimental data, were rigorously validated using the analysis of variance, main effects plots, residual analysis, and the R 2 and Adj. R 2 values. Additionally, the heat transfer search (HTS) algorithm was employed for process optimization. While single-objective optimization provided optimal settings for individual responses, simultaneous optimization aimed to strike a balance between multiple, sometimes conflicting, objectives. This comprehensive approach resulted in specific values, including a reinforcement (R) of 4.285 mm, a width (W) of 9.906 mm, a DOP of 2.039 mm, and an HAZ width of 2.020 mm. These values were achieved with specific input parameters: current (221 A), voltage (24 V), and GFR (21 L·min−1). The Pareto solutions offered a nuanced selection of the most suitable configuration, taking into account the desired values for R, W, DOP, and HAZ. The close alignment between predicted and experimentally measured values for the responses highlights the precision and suitability of the HTS algorithm in estimating critical bead geometries during GMAW of S690QL plates.

Investigation of a Low-Speed Commutation Voltage Shock Problem in Three-Level ANPC Inverter with Hybrid Modulation Mode

With the development of the photovoltaic industry; there will be an increasing demand for efficient, high-power density, and low-cost grid interface converters. Compared with two-level inverters, multilevel inverters have the following advantages: (1) lower device voltage ratings; (2) better output filtering spectrum; (3) lower electromagnetic interference (EMI) noise; and (4) higher switching speed capability. However, the complex switching circuit of the multilevel inverter will bring more parasitic inductance, resulting in severe switching overvoltage (ringing). Especially in order to reduce the cost of the inverter, using the long-loop modulation mode, the commutation loop will introduce more parasitic inductance, which will make the overvoltage more serious. Consider that commonly used overvoltage absorption schemes are effective only for overvoltage or suppression of oscillations. Therefore, a new overvoltage absorption circuit is proposed in this paper, which can not only alleviate the overvoltage and ringing phenomena but also suppress the effect of voltage jumps during low-frequency switching on high-frequency input voltage. This overvoltage absorption circuit is characterized by low overvoltage, fast ringing damping, and minimum capacitance. Experiments and simulations are conducted to verify the effectiveness of this overvoltage absorption circuit using a three-level ANPC inverter as a prototype. The results show that the proposed overvoltage absorption circuit can significantly reduce the overvoltage level, shorten the oscillation time, and reduce the voltage difference between the upper and lower DC bus capacitors.

Multi-Weld Quality Optimization of Gas Tungsten Arc Welding for Aluminium 6061 using the Grey Relation Analysis-Based Taguchi Method

The optimization of parameters is crucial in the joining process, particularly in welding, to attain connections with exceptional mechanical properties. In the present study, the welding of aluminium 6061 was conducted with a TIG, an acronym for tungsten inert gas, is formally referred to as gas tungsten arc welding (GTAW) technique, employing a suitable ER 4043 electrode and argon shielding gas. The investigation of optimal welding parameters, specifically current, voltage, and flow rate, is conducted utilizing statistical methodologies such as the hybrid Grey-based Taguchi process. The desired attributes for high-quality welds were established as having high tensile strength, hardness, and a low rate of corrosion. Given the presence of three responses and one objective, the hybrid Grey-based Taguchi method is employed. The statistical approaches have converged on optimal parameters of 120 A, 20 V, and 15 L/min. The present analysis reveals that the ideal welded junction exhibited the following characteristics: a tensile strength of 190.169 MPa, a hardness value of 77HV, and a corrosion rate of 0.29 mm. The current parameter was found to have the highest contribution, accounting for 65.66% of the overall performance of the weldments. Confirmatory testing was conducted in order to confirm the optimization strategy, and the findings indicated that the Grey-based Taguchi technique is a straightforward yet effective approach for optimizing welded connections across several performance criteria.

Design, Development and Testing of Microcontroller Systems Simulator using PIC Microcontroller

The inadequacy or absence of training equipment negatively impacts student performance, achievement and employability. Attempting to address this problem, the study was conducted to design, develop, fabricate and test a microcontroller systems simulator (MSS). The MSS was composed of the mainboard and development board comprising the PIC microcontroller, microcontroller circuits and input and output devices. The MSS was designed using AutoCAD, schematic design and circuit simulation software, and printed circuit board auto-routing software. A computerized cutting machine, laser laminator and ink printer were also used in the fabrication of the MSS boards. Test results showed that 12 and 24 VDC voltage readings were normal, sensors were working with the indicated specifications, and the MSS could perform automatic switching simulations. It was concluded that the MSS can effectively demonstrate microcontroller experiments and switching applications and it conformed to the required voltage and current ratings, electronics and electrical safety standards. It was also found that it is technically feasible to develop a microcontroller simulator utilizing commercially and locally available materials and spare parts.