Electrical Engineering Applications Research Articles

Advancing Electrical Engineering with Biomass-derived Carbon Materials: Applications, Innovations, and Future Directions.

The ongoing global shift towards sustainability in electrical engineering necessitates novel materials that offer both ecological and technical benefits. Biomass-derived carbon materials (BCMs) are emerging as cornerstones in this transition due to their sustainability, cost-effectiveness, and versatile properties. This review explores the expansive role of BCMs across various electrical engineering applications, emphasizing their transformative impact and potential in fostering a sustainable technological ecosystem. The fundamentals of BCMs are investigated, including their unique structures, diverse synthesis procedures, and significant electrical and electrochemical properties. A detailed examination of recent innovations in BCM applications for energy storage, such as batteries and supercapacitors, and their pivotal role in developing advanced electronic components like sensors, detectors, and electromagnetic interference shielding composites has been covered. BCMs offer superior electrical conductivities, tunable surface chemistries, and mechanical properties compared to traditional carbon sources. These can be further enhanced through innovative doping and functionalization techniques. Moreover, this review identifies challenges related to scalability and uniformity in properties and proposes future research directions to overcome these hurdles. By integrating insights from recent studies with a forward-looking perspective, this paper sets the stage for the next generation of electrical engineering solutions powered by biomass-derived materials, aligning technological advancement with environmental stewardship.

Modeling Borehole Resistivity Logs with Exponentially Graded Multilayered Soil Inversion for Electrical Engineering Applications

In this paper, we present the application of a special soil resistivity model, the Exponentially Graded Multilayered Soil model, to the interpretation of Borehole Resistivity Logging surveys. The model, which was recently introduced by the authors, offers an alternative to the interpretation provided by constant resistivity layer models. The model is applied to synthetic soil surveys as well as to a real survey that is not satisfactorily interpreted using conventional models. This model aids in the design and calculation of grounding systems in electrical engineering, providing an alternative to calculations performed by traditional layered models.

A Novel Approach to Transient Fourier Analysis for Electrical Engineering Applications

This paper presents a detailed investigation into the application of transient Fourier analysis in select electrical engineering contexts. Two novel approaches for addressing transient analysis are introduced. The first approach combines the Fourier series with the Laplace–Carson (L-C) transform in the complex domain, utilizing complex time vectors to streamline the computation of the original function. The inverse transformation back into the time domain is achieved using the Cauchy-Heaviside (C-H) method. The second approach applies the Fourier transform (F-Τ) for the transient analysis of a power converter circuit with both passive and active loads. The method of complex conjugate amplitudes is employed for steady-state analysis. Both contributions represent innovative approaches within this study. The process begins with Fourier series expansions and the computation of Fourier coefficients, followed by solving the system’s steady-state and transient responses. The transient states are then confirmed using the Fourier transform. To validate these findings, the analytical results are verified through simulations conducted in the Matlab/Simulink R2023b environment.

First-Principles Investigation on Ru-Doped Janus WSSe Monolayer for Adsorption of Dissolved Gases in Transformer Oil: A Novel Sensing Candidate Exploration.

Using first-principles theory, this work purposes Ru-doped Janus WSSe (Ru-WSSe) monolayer as a potential gas sensor for detection of three typical gas species (CO, C2H2, and C2H4), in order to evaluate the operation status of the oil-immersed transformers. The Ru-doping behavior on the WSSe surface is analyzed, giving rise to the preferred doping site by the replacement of a Se atom with the formation energy of 0.01 eV. The gas adsorption of three gas species onto the Ru-WSSe monolayer is conducted, and chemisorption is identified for all three gas systems with the adsorption energy following the order: CO (-2.22 eV) > C2H2 (-2.01 eV) > C2H4 (-1.70 eV). Also, the modulated electronic properties and the frontier molecular orbital are investigated to uncover the sensing mechanism of Ru-WSSe monolayer upon three typical gases. Results reveal that the sensing responses of the Ru-WSSe monolayer, based on the variation of energy gap, to CO, C2H2, and C2H4 molecules are calculated to be 1.67 × 106, 2.10 × 105, and 9.61 × 103, respectively. Finally, the impact of the existence of O2 molecule for gas adsorption and sensing is also analyzed to uncover the potential of Ru-WSSe monolayer for practical application in the air atmosphere. The obtained high electrical responses manifest strong potential as a resistive sensor for detection of three gases. The findings hold practical implications for the development of novel gas sensing materials based on Janus WSSe monolayer. We anticipate that our results will inspire further research in this domain, particularly for applications in electrical engineering where the reliable detection of fault gases is paramount for maintaining the integrity and safety of power systems.

Dual-gradient MXene/AgNWs/Hollow-Fe3O4/CNF composite films for thermal management and electromagnetic shielding applications

With the increasing prevalence of electronic devices, there is a pressing need for composite films that offer both efficient thermal management and superior electromagnetic interference (EMI) shielding. To address this, we developed a novel composite film featuring a controllable conductive-magnetic dual-gradient structure, composed of cellulose nanofibers (CNF), MXene, silver nanowires (AgNWs), and hollow ferric oxide (Fe3O4). This film was fabricated using a straightforward, cost-effective layer-by-layer vacuum filtration method. Leveraging CNF as the matrix material endows the film with remarkable flexibility. The integration of 2D MXene, 1D AgNWs, and 0D hollow Fe3O4 significantly enhances the film's thermal conductivity through multidimensional particle interactions, achieving a maximum value of 2.92 W/mK. Additionally, the dual-gradient structure of the film-comprising a transition layer and a reflection layer-improves EMI shielding efficiency by balancing high EMI shielding effectiveness with low electromagnetic wave reflection. Specifically, for the dual-gradient configuration (MAF)-25-CNF, the absorption coefficient (A) of electromagnetic waves incident on the low conductivity side reaches 0.23, and the shielding effectiveness reaches 45.8 dB. These findings highlight the potential of MXene/AgNWs/Fe3O4/CNF composite films with a controllable conductive-magnetic dual-gradient structure for applications in electronics, electrical engineering, and wearable technologies.

Nanofluids containing conductive nanoparticles: the review of thermal and electrical properties. Selected applications in electrical and thermal engineering, and energy sector

Nanofluids containing conductive nanoparticles: the review of thermal and electrical properties. Selected applications in electrical and thermal engineering, and energy sector

Cancellation of Steady State Error Using Auxiliary Diophantine Equation for a Bio-Reactor Process -A case study

RST (Regulation, Sensitivity and Tracking) controller is very widely used in electrical engineering application. The controller provides both feed-forward and feedback actions. PID, Internal Model Controller (IMC) designs are mainly very effective in set point tracking but poor in disturbance rejection, however, the disturbance rejection can be obtained at the cost of reduced stability margins. The controller is based on the resolution of a Diophantine equation. A mathematical Model for Bioreactor was developed using MATLAB. Once the discrete model of the process is known and a model transfer function for the closed loop system has been chosen, the cancellation of steady state errors in response to reference signals has been solved for polynomial reference signals of any order by the introduction of an auxiliary Diophantine equation. The results are compared with the PID controller based on pole assignment method.

Photoconductivity of explosive percolation in conductive polymer/graphene oxide nanocomposite films

AbstractIn this study, we explored the behavior of protonated polyaniline/graphene oxide (PANI‐CSA/GO) nanocomposite films with varying GO concentrations, focusing on the novel phenomenon of explosive percolation. We observed a significant increase in electrical conductivity at the explosive percolation threshold, attributed to the emergence of a percolating metallic pathway. This discovery positions PANI‐CSA/GO films as promising materials for various electronic and electrical engineering applications. Additionally, the films demonstrated consistent and repeatable photoconductivity, showing potential for use in high‐performance UV‐photodetectors, photoactive layers in solar cells, light‐emitting diodes, and energy storage devices. Structural analyses using fourier transform infrared spectroscopy (FTIR) and x‐ray diffraction (XRD) confirmed successful GO incorporation within the PANI‐CSA matrix. Different morphological features were observed depending on the GO volume fraction, with increased GO enhancing thermal stability in the conductive zone. Our findings highlight the immense potential of PANI‐CSA/GO nanocomposite films in advanced electronic applications, emphasizing their novel conductive and photoconductive properties and improved thermal stability.

Application of electrical engineering in electric power system

Application of electrical engineering in electric power system

A three-term conjugate gradient descent method with some applications

The stationary point of optimization problems can be obtained via conjugate gradient (CG) methods without the second derivative. Many researchers have used this method to solve applications in various fields, such as neural networks and image restoration. In this study, we construct a three-term CG method that fulfills convergence analysis and a descent property. Next, in the second term, we employ a Hestenses-Stiefel CG formula with some restrictions to be positive. The third term includes a negative gradient used as a search direction multiplied by an accelerating expression. We also provide some numerical results collected using a strong Wolfe line search with different sigma values over 166 optimization functions from the CUTEr library. The result shows the proposed approach is far more efficient than alternative prevalent CG methods regarding central processing unit (CPU) time, number of iterations, number of function evaluations, and gradient evaluations. Moreover, we present some applications for the proposed three-term search direction in image restoration, and we compare the results with well-known CG methods with respect to the number of iterations, CPU time, as well as root-mean-square error (RMSE). Finally, we present three applications in regression analysis, image restoration, and electrical engineering.

Computational multiscale modelling of material interfaces in electrical conductors

Material interfaces occur at various length scales and may exhibit significantly different properties than the surrounding bulk. Motivated by their importance for electrical engineering applications such as wire bonds and electrically conductive adhesives, the focus of the present work is on material interfaces in electrical conductors. In order to approximate the physical interphase (of finite thickness) as a (zero-thickness) cohesive zone-type interface in macroscale simulations, scale-bridging relations are established that relate the apparent electro-mechanical interface properties to the underlying microstructure. A finite element-based implementation is discussed with particular focus lying on the efficient calculation of the flux-type macroscale quantities and the associated generalised algorithmic consistent tangent stiffness tensors. Analytical solutions are derived for validation purposes and representative boundary value problems are studied.

A practical algorithm for the design of multiple-sized porous scaffolds with triply periodic structures

In this study, we present a practical volume-merging method for generating multiple-sized porous structures that exhibit geometries with triply periodic minimal surface (TPMS) lattice structures. The proposed method consists of three stages: (1) designing the physical models with a signed distance field, (2) performing a merging operation for the porous scaffolds, and (3) assembling different units into a composite structure. The significant advantages of the proposed algorithm can be summarized as follows: Our method is independent of the model shape; the designed structures maintain a smooth surface with a constant mean curvature, and the mathematical computational complexity is low. We can join two different-sized triply periodic minimal surface lattices in the radial direction, where the transition region is obtained by smooth interpolation between the two lattice structures with different cell sizes or types. However, constructing large-sized models is only conceptually possible due to computational cost and memory storage constraints. To overcome these limitations, we present a practical method that can efficiently assemble large-scaled models at a low computational cost. The proposed method is based on a Boolean union operation of basic units of TPMS. Thus, it is simple to generate large-scale three-dimensional multiple-sized porous volumes based on our proposed method, which can be applied to many applications in mechanical and electrical engineering. The produced multi-scale compound scaffolds have smooth surfaces without fractures, making them suitable for straightforward application in additive manufacturing. Several numerical tests are conducted to validate the efficiency of the proposed algorithm.

Conformable Triple Sumudu Transform with Applications

One of the important topics in applied mathematics is the topic of integral transformations, due to their importance in electrical engineering applications, including communications in particular, and other sciences. In this work, one of the most important transformations in its three dimensions was presented, which is the triple Sumudu transform, including solving some real-life applications of physics, some of which have not been solved using such an integral transform before. In this work, we extend the Sumudu transform formula to the conformable fractional order, as well as other interesting and significant rules. The general analytical solution of a singular and nonlinear conformable fractional differential equation based on the conformable fractional Sumudu transform is also presented in this paper. The general solutions of several linear and nonhomogeneous conformable fractional differential equations can be obtained using the method we’ve proposed. As a result, our results reveal that our proposed method is an efficient one that can be used for solving all conformable fractional differential equations. The relationship between the Sumudu integral transform and other important and recently proposed integral transforms are also discussed. Finally, the triple Sumudu transform is used to solve boundary value problems, such as the heat equation with boundary values. The triple Sumudu integral transform is also used to solve linear partial integro-differential equations. The transform capability to handle such equations has been proven via its utilization in three applications.

An overview on Finite Different Method (FDM) in multilayer thermal diffusion problem

Numerous mathematical models have been developed for thermal diffusion through single-layer materials, while further developments are needed for multi-layer materials. Diffusion processes through a multilayer material are of interest in industrial, applied thermodynamics, physics, electrical and civil engineering applications. The proposed scheme is easily applicable in various fields, demonstrating that Finite Different Methods (FDMs) are flexible, simple to implement and help to represent multilayer materials even without associating them with other numerical methods. The numerical method studied is a FDM in a civil engineering application. Through the study of a multilayer wall, its criticalities are highlighted, and a possible implementation is proposed.

Comparison of physical properties of ferrofluids based on mineral transformer oil and bio-degradable gas-to-liquid oil

Ferrofluids based on mineral transformer oil have been intensively studied over two decades owing to their outstanding thermal and electrical insulating properties. However, current environmental demands on transformer operation give priority to the use of biodegradable transformer oils. Clearly, the differences in physical properties of biodegradable oils and those refined from crude oil determine the physical properties of ferrofluids based on the two types of oils. In this study, ferrofluids with various concentrations of iron oxide nanoparticles have been prepared on mineral transformer oil (M−oil) and biodegradable transformer oil based on gas-to-liquid technology (S-oil). The ferrofluids were subjected to experimental investigation of magnetization, AC magnetic susceptibility, thermal conductivity, viscosity and dielectric response. Based on zero-field-cooled and field-cooled magnetization curves, a lower temperature of a specific magnetization maximum associated with the melting of the oil (phase transition) was found for M−samples than for S-samples. The effect of carrier liquid on the onset of extrinsic superparamagnetism in addition to the intrinsic superparamagnetism is observed. Spectra of AC magnetic susceptibility of both types of ferrofluids exhibit quasi constant behaviour with amoderate decrease at high frequencies of amagnetic field. The viscosity of M−samples is slightly higher than that of S-samples. On the other hand, M−samples exhibit lower thermal conductivity than S-samples. In both cases, the thermal conductivity linearly decreases with temperature. Dielectric spectroscopy has revealed remarkable dielectric dispersion below 100 Hz in both ferrofluid types. The relaxation has been ascribed to interfacial polarization, which can be considered as a serious drawback from an electrical engineering application point of view. The measured physical properties of the ferrofluids are analyzed in regard to the density and viscosity of the base oils.

3D Printed All-Natural Hydrogels: Flame-Retardant Materials Toward Attaining Green Sustainability.

Biomass-based hydrogel is a promising flame-retardant material and has a high potential for applications in transportation, aerospace, building and electrical engineering, and electronics. However, rapid vat photopolymerization (VP) 3D printing of biomass-based hydrogels, especially that of all-natural ones, is still rare. Herein, a new class of VP 3D-printed hydrogels with strong covalent networks, fabricating using fully biomass materials and a commercial liquid crystal display (LCD) printer assembled with low-intensity visible light is presented. Encouragingly, the highly ordered layer-by-layer packing structures provided by VP 3D printing technology endow these hydrogels with remarkable flame retardancy, exceptional temperature resistance, advantageous combustion behaviors, and favorable mechanical strength, in particular, giving them a better limit oxygen index (83.5%) than various biomass-based hydrogels. The proposed approach enables the green design as well as the precise and efficient preparation for flame-retardant materials, paving the way for the future flame-retardant materials toward attaining green sustainability.

Carbon nanotubes/aluminum interface structure and its effects on the strength and electrical conductivity of aluminum

The contradiction between strength and electrical conductivity of pure aluminum (Al) hinders its wide applications in electrical engineering. In this study, an attempt was made to overcome this limitation by adding carbon nanotubes (CNTs) into Al matrix using friction stir processing (FSP) method. The results showed that CNTs were singly distributed in Al matrix and strong bonded CNTs/Al interfaces without chemical reaction as well as impurity contamination were formed. Interestingly, it was found that the axis of CNTs tended to be parallel to Al (111) planes, which provided a geometric basis for the formation of semi-coherent CNTs/Al interfaces. These semi-coherent CNTs/Al interfaces possessed an extremely low electrical resistivity, which weakened the total electron scattering generated by all CNT/Al interfaces. Meanwhile, strong bonded CNTs/Al interfaces effectively hindered dislocations movement, inducing an improvement of 84 % and 50 % in yield strength and tensile strength of Al respectively. As a result, the strength of Al was significantly improved without losing its electrical conductivity. This study provides a new strategy for breaking through the contradiction between strength and electrical conductivity of Al and then producing CNTs/Al nanocomposites with high strength and high electrical conductivity.

Physics-Informed Neural Networks for Solving 2-D Magnetostatic Fields

Physics-informed neural network (PINN) has shown great potential in the inverse and parametric designing problems in electrical engineering. Moreover, most existing works on PINN are dedicated to computational fluids, and very few attentions have been paid to static and low-frequency electromagnetic near fields with multiple media in electrical engineering applications. In this work, a PINN for solving two-dimensional (2D) magnetostatic fields in electromagnetic devices and systems is proposed. The magnetic field intensity and the magnetic vector potential are solved by training a neural network which encodes partial differential equations and boundary conditions as residuals. The computation of the spatial derivatives of media constitutive parameters, which negatively impacts the training of PINN, is eliminated. A mesh-assisted non-uniform sampling method for the selection of collocation points is proposed to further improve the performance of PINN. The proposed PINN is verified by comparing its results with those of the finite element method in two 2D magnetostatic case studies. It is expected that this work will promote further applications of PINN in the modelling, numerical analysis, and parametric design of electromagnetic devices and systems.

A Reconfigurable 4th Order IIR Filter For The Low Frequency Applications

Huge numbers of advanced electrical engineering applications employ infinite impulse response (IIR) filters very frequently in order to meet market’s demands. Especially, some applications such as video processing, digital signal processing and high-speed digital communication necessitate computational efficiency and low latency. In this point of view, high-speed processing of digital data require a digital signal processor or an FPGA instead of a conventional microprocessor. In this respect, in the last decades, FPGAs are commonly used in order to bring new opportunities to the designers. This work gives a FPGA hardware design of a 4th order IIR reconfigurable filter structure. The proposed filter’s maximum clock frequency is around 32MHz which covers different low frequency applications from biomedical signal processing up to speech applications. To verify the performance of the filter, 4th order Butterworth and Chebyshev filters are realized in the basis of Matlab results and FPGA behavioral model. Also, consuming logic gates and blocks are given in order to evaluate chip area occupation. It should be considered that the proposed filter scheme presents promising results to meet low frequency applications.

Mechanical Analysis and Constitutive Modeling of Nonlinear Behavior of Silver-based Conductive Ink

Stretchable electronic devices are progressively deployed in many applications of mechanical, electrical, and bio-medical engineering. These circuits are made of stretchable and flexible substrate, as well as conductive ink, and various electronic components. The choice of components and layouts for the substrate and conductive ink can regulate the stretchability of stretchable circuits. On top of that, the substance utilized to create the conductive ink must have high electrical conductivity and strong adherence to the substrate in order to produce a high-quality stretchable printed circuit. Thus, this study focused on the development of stretchable conductive ink using silver powder as a conductive filler and PDMS-OH as a binder. The mechanical properties of the synthesized ink were investigated via simple uniaxial tensile testing method and nanoindentation technique, respectively. Accordingly, the modulus of elasticity, tensile stress and yield stress of the ink were obtained as 5.72 MPa, 1.195 MPa, and 0.86 MPa, congruently at 137% strain before undergoing failure. The experimental stress-strain data was then employed on the elastic-plastic constitutive model to investigate the elastomeric properties of the ink as it is an alternative method of lengthy and expensive procedures of validating different polymers. Moreover, the hardness and reduced modulus of the ink were evaluated by nanoindentation method using 5 mN maximum load with 0.5 mN/s loading/unloading rate and 2 secs holding time. Consequently, the hardness and reduced modulus values were obtained as 1.45 MPa and 34.53 MPa, respectively. These values were further validated by Oliver-Pharr method, and were in a good agreement.