Film capacitors are indispensable in electrical engineering; however, balancing the insulation and thermal stability of polymer dielectrics remains a key challenge for high-temperature energy storage.

Techno-economic analysis with a dynamic optimization approach integrating electrical and chemical engineering: A case study for aviation decarbonization in Japan

The Effect of Software-Based Mind Map of Educational Design in Development of the Electrical Engineering Students' Learning Level

Recent Activities of History of Electrical Engineering Committee (HEE)

Integrating hands-on and simulation-based approaches for teaching electronic circuit design in measurement technology at the faculty of electrical engineering, department of measurement, CTU in Prague

The sixties (60s) and seventies (70s) of the last century have seen the takeoff of microelectronics. Since that, several countries, including Algeria, have adopted planned strategic programs to develop their domestic electronics. In this paper, we provide a historical review of the evolution of the electrical test benches developed at the Division of Microelectronics and Nanotechnology (DMN) of the “Centre de Développement des Technologies Avancées” (CDTA) or Center for Development of the Advanced Technologies. Starting from mid- nineties to up today, the electrical characterization platform has known different generations of test benches; from a simple setup to extract current-voltage (I-V) and capacitance-voltage (C-V) characteristics of semiconductor devices to more sophisticated ones to extract spectra of electrically detected magnetic resonance (EDMR). In addition, some benches have been developed to study reliability issue in metal oxide semiconductor (MOS) devices and integrated circuits (ICs), such as ionizing radiation effects, Fowler-Nordheim (FN) stress, hot-carrier injection (HCI), time-dependent dielectric breakdown (TDDB), and bias temperature instability (BTI). The obtained results have been published in well-known journals of the Institute of Electrical and Electronics Engineers (IEEE), the American Institute of Physics (AIP), and the Elsevier publishers.

This study introduces a portable radar system for real‐time monitoring of respiratory and heart rates in dairy cows. It uses millimeter‐wave Frequency Modulated Continuous Wave (FMCW) radar to perform noncontact physiological sensing, reducing behavioral disturbance. The radar system's design prioritizes portability, cost‐effectiveness, and robustness, allowing deployment in diverse farm environments. Experimental results show strong agreement between radar‐derived and reference measurements, confirmed through correlation analysis and supervised classification. Additionally, the study explores the integration of radar monitoring with advanced data analysis techniques, including Principal Component Analysis (PCA) and Support Vector Machines (SVM), to enhance livestock health management processes. The system is validated for its capability to monitor respiratory and heart rates in real time and effectively classify cows' reproductive states, achieving a classification accuracy of 79.63% for estrus detection. These findings demonstrate the feasibility of radar‐based physiological monitoring and support future integration with data‐driven management tools. © 2025 The Author(s). IEEJ Transactions on Electrical and Electronic Engineering published by Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

The study of the industrial development of the Chuvash Autonomous Soviet Socialist Republic during the seven years makes it possible to identify a key moment in the change in the economic structure of the region, which is the basis of its social life. The article describes the transformation process of the economy of the Chuvash ASSR during the years of the seven-year plan for the development of the national economy, examines the indicators of the region’s industry, as well as summarizes the results of economic development and changes in the structure of the economy of Chuvashia when implementing the seven-year plan. The relevance of the work is due to the fact that this aspect of the region’s life is poorly understood. The purpose of the study is to examine the plans of industrial development of the Chuvash ASSR in 1959–1965 and to give an objective assessment to the industrial potential of the region in this period. Materials and methods. When writing the article, archival materials containing summary statistical data on the economy of this period, as well as the works of leading experts on the industrial development of Chuvashia in the second half of the twentieth century, were used. The work is based on general scientific and special historical approaches, among which it is worth noting the principles of objectivity, consistency and historicism. Results. The industry of the Chuvash ASSR went through global changes during the seven years of 1959–1965. New knowledge-intensive industries emerged in the republic, and the basis of the region’s economy changed: if at the beginning of the seven-year period consumer goods and woodworking industries had the greatest share, then by the end of the seven-year period mechanical engineering and chemical industries took the first place. Within the framework of mechanical engineering, the instrument-making and radio engineering industries grew the fastest, and the electrical engineering and machine-building industries provided the largest production volume in numerical terms. In addition to the emergence of new industries, the old ones were also actively developing and expanding in the republic. The seven-year plan was fulfilled by 103% by the republic’s industry, which demonstrates the efficiency of production. Conclusions. In 1959–1965, the economy of the Chuvash ASSR underwent changes, its structure was transformed, and a cluster of high-tech industries, such as instrument engineering and the electrical industry, was created and developed in the republic. The Chuvash economy was able to become industrial from a predominantly agrarian one, dramatically increasing the volume of industrial production and, as a result, significantly increasing the overall economic potential of the region. As part of this economic transformation, the industrial base for the further development of the region in the next five years was also laid.

Modern energy and electronic systems comprise a large number of nonlinear elements operating in dynamic modes. Accurate modeling of such systems requires proper consideration of nonlinear current-voltage characteristics (CVC) and transient processes, which is especially important when designing rectifiers, inverters, control systems and other power electronics devices. Existing electrical circuit simulators do not always provide users with the necessary flexibility, scalability, or compatibility with enterprise safety standards, and may have legal restrictions. Custom effective modeling methods for such systems allow for creating specialized software solutions to analyze dynamic modes of electrical circuits, free from the limitations of commercial simulators and tailored to specific engineering and scientific tasks. The purpose of the work is to develop a method for numerical modeling of dynamic modes of electrical circuits comprising semiconductor diodes or other elements with nonlinear CVC, described by nodal equations. The scientific novelty lies in the development of a homotopy approach to overcoming high condition number of the Jacobian matrix when solving nonlinear differential-algebraic equations (DAEs) of electrical circuits, based on deformation of CVC with adaptation of the deformation parameter depending on the residual norm and condition number of the matrix; in the development of a method for extracting linearly independent differential equations from DAEs of electrical circuits without preliminary analysis of their topology; in the development of a universal stamp of a nonlinear element, based on linearization of the functional in the vicinity of the current approximation, allowing for integration of diode models with various CVCs into nodal equations. Materials and methods. Theoretical electrical engineering methods were used in the work, including the modified nodal potential method. The proposed numerical modeling method involves integration of elements with nonlinear CVC into nodal equations; extraction of differential and algebraic parts from DAEs, based on singular value decomposition of the matrix standing before the derivative vector; transformation of DAEs into a nonlinear system of algebraic equations using backward differentiation formulas (BDF) with variable time step. Initial points for BDF were determined by the diagonally implicit Runge–Kutta method of second order accuracy. Numerical solution of the obtained nonlinear equations was performed by the damped Newton–Raphson method. To reduce the condition number of the Jacobian matrix in transient modes, when the spread of differential conductivities reaches 12 orders and higher, a homotopy approach was proposed, consisting of gradual deformation of the diode CVC from a smoothed to the original curve during convergence, while maintaining a given value of the condition number. Results. To demonstrate the proposed solutions, computer simulation of a bridge rectifier operating on an active-inductive load with two types of diode CVC was performed: piecewise-linear and smooth, corresponding to the Shockley equation with series resistance. The deformation parameter and damping coefficient were adaptively changed depending on the residual norm of the functional and the condition number of the Jacobian matrix. Comparison of simulation results with different methods of specifying diode CVC showed that differences appear predominantly in transient processes of switching diode operation modes. It has been found that to ensure convergence of numerical solution in diode switching modes, characterized by high condition number of the Jacobian matrix, the homotopy approach is more effective than diagonal regularization. The proposed method for numerical modeling of dynamic modes of electrical circuits with nonlinear elements has a natural algorithmic structure, allowing for simple software implementation. Conclusions. 1. The most universal diode stamp, obtained on the basis of linearization of the functional derived from the CVC equation in the vicinity of the current approximation, has been identified. 2. A method for extracting linearly independent differential equations from DAEs of electrical circuits without preliminary analysis of circuit topology has been proposed. 3. A method for calculating the Jacobian matrix for solving nonlinear DAE has been proposed. 4. To ensure convergence of numerical solution with high condition number of the Jacobian matrix, it is preferable to apply the homotopy approach.

This paper proposes a novel hybrid model (QMD‐SSA‐BiLSTM‐Attention) for predicting dissolved gas concentrations in transformer oil to enhance fault diagnosis and condition monitoring. The methodology integrates quadratic mode decomposition (QMD), combining optimal variational mode decomposition (OVMD) and complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) for robust signal processing. The primary decomposition employs VMD based on center frequency intervals, while CEEMDAN further decomposes residual sequences. A bidirectional LSTM network with attention mechanism serves as the core predictor, with sparrow search algorithm (SSA) optimizing hyperparameters. Final predictions are reconstructed through subsequence superposition. Comparative error analysis demonstrates the model's superior accuracy over existing methods. The approach provides critical technical support for transformer condition assessment and early fault warning by improving the forecasting of gas concentration. Key innovations include the dual‐stage QMD framework and the integration of SSA‐optimized attention‐BiLSTM, addressing nonlinearity and non‐stationarity in gas dissolution patterns. This research advances predictive maintenance strategies for power transformers through data‐driven decomposition‐ensemble techniques. © 2025 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

Against the backdrop of educational digital transformation, the value of traditional blackboard teaching in Electrical Engineering Fundamentals courses at military academies and training institutions warrants reassessment. This discipline emphasises logical deduction and engineering modelling; overreliance on multimedia risks trapping students in a ‘understand but cannot apply’ predicament. This paper analyses current issues such as formalism and fragmentation in blackboard writing, proposing eight strategies: ‘Anchoring Objectives, Leveraging Strengths, Gauging Proportion, Systematic Planning, Standardised Presentation, Activating Generation, Aligning Characteristics, and Integrating Intelligence’. The author recommends that chalkboard writing should evolve from experiential notation into structured cognitive scaffolding, rather than remaining a technical appendage. Practice demonstrates that scientifically reconstructed chalkboard writing can both underpin knowledge construction in circuit analysis and safety protocols, and integrate the cultivation of ‘extreme responsibility and meticulous rigour’ in maintenance personnel. This provides a low-cost, high-benefit teaching pathway for nurturing military engineering talent in the new era.

Coastal erosion in Tra Vinh province and the Mekong Delta region is becoming increasingly severe due to various factors, among which hydrodynamic conditions (tides, waves, river, and sea currents) play a crucial role. This study utilizes the MIKE 21/3 Coupled Model FM to assess the effectiveness of two coastal protection scheme options for the coastal area of Hiep Thanh commune, Tra Vinh: reinforced concrete revetment (Option 1) and hybrid revetment (trees branch fences, geotube bags, and perforated breakwater – Option 2). The results indicate that Option 1 provides better protection for the existing shoreline. However, Option 2 demonstrates superior performance in wave attenuation and beach nourishment, with the ability to reduce wave height approaching the shore by up to 70%. Option 2 also contributes to erosion reduction and shoreline lowering during the Northeast monsoon season (high water levels and strong waves). This study provides a scientific basis for selecting a suitable coastal protection scheme for the Hiep Thanh commune and can serve as a reference for areas with similar natural conditions. © 2025 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

Radiofrequency (RF) exposure has been extensively studied for potential health risks. Unlike ionizing radiation, RF fields primarily cause thermal health effects, the only established mechanism of biological harm. Regulatory bodies, including the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and the Institute of Electrical and Electronics Engineers (IEEE), set limits to prevent excessive heating. This review examines the relationship between RF exposure, heat generation, and physiological responses, with relevance to civilian and military safety. A narrative review of peer-reviewed literature, regulatory reports, and experimental studies was conducted using PubMed, IEEE Xplore, Google Scholar and Scopus. Emphasis was placed on Specific Absorption Rate (SAR) and Cumulative Equivalent Minutes at 43 °C (CEM43). Studies on thermal effects and exposure scenarios were prioritized; speculative non-thermal mechanisms were excluded. Thermal effects depend on frequency, tissue composition, and environmental conditions. Whole-body SAR limits (≤4 W/kg) generally prevent core temperature increases, but localized heating remains a concern. CEM43 provides a temperature-based metric but is difficult to apply in transient exposures. Penetration depth across NATO frequency bands shows variability because of differences in tissue models and measurement methods. This variability is clinically relevant, as localized heating of the skin, eye, or superficial nerves may occur even when whole-body exposure is within limits. Current guidelines prevent systemic overheating but may not fully address localized risks. Combining SAR and CEM43 with refined penetration depth data could improve risk assessment. Future work should refine dose-response thresholds and methods for detecting and modeling localized heating, especially under military conditions where thermoregulation may be impaired.

The integration of artificial intelligence into engineering workflows has opened new frontiers for design automation and innovation. This paper explores an AI-driven approach to electrical engineering design, leveraging the capabilities of large language models (LLMs) such as GPT-4 to enhance both accuracy and efficiency. We propose a novel framework named ELEGANT (Electrical Engineering design Assisted by Natural-language Transformers), which utilizes LLMs to assist in key stages of electrical design, including schematic generation, component selection, and simulation parameter tuning. Unlike existing approaches, ELEGANT uniquely integrates a multi-stage natural language prompt parsing with domain-specific circuit simulation feedback, enabling adaptive and precise design automation. This leads to significant improvements in design speed and accuracy, while providing an intuitive user experience that bridges human intent with AI-driven execution. By aligning natural language prompts with engineering intent, our method enables intuitive interaction between human designers and AI systems, facilitating faster iteration and reduced design errors. We further introduce prompt engineering techniques and domain-specific adaptations to improve the performance of LLMs in electrical engineering tasks. Experimental results on several design scenarios demonstrate that our AI-assisted approach outperforms traditional methods in terms of design speed and correctness. This work highlights the transformative potential of LLMs in accelerating and augmenting electrical engineering design processes.

This study presents a novel and efficient modal analysis framework for thick cylindrical structures with complex geometry and material variability, subject to arbitrary boundary conditions. The methodology is applied to an electric motor (e-motor) stator assembly modelled as a thick cylindrical shell incorporating stator teeth, windings, and housing or cooling jacket effects. The model accommodates both continuous and piecewise variations in material properties and thickness. Based on First-Order Shear Deformation Shell Theory (FSDST), it accounts for shear deformation, rotary inertia, and trapezoidal stress distributions, enabling accurate prediction of axial, circumferential, torsional, and bending vibration modes. A segmentation approach is used along the axial direction, with artificial massless springs enforcing continuity and permitting general boundary conditions. Displacement fields are constructed using orthogonal Jacobi polynomials, and the eigenvalue problem is solved via the Rayleigh–Ritz method. Notably, the methodology allows accurate and efficient prediction of axisymmetric (breathing) modes in thick, non-uniform cylindrical shells – a capability rarely addressed in existing literature, despite its importance in Noise, Vibration, and Harshness (NVH) analysis. Validation against Finite Element Analysis (FEA) and Experimental Modal Analysis (EMA) on both generic cylindrical shells and a real Permanent Magnet Synchronous Machine (PMSM) stator shows excellent agreement, with natural frequency deviations typically below 5% and highly consistent mode shapes. The framework also achieves over 95% reduction in computational time compared to FEA, establishing it as a highly adaptable and practical tool for vibration analysis in electric motor design and NVH engineering applications.

Bioelectronics is a rapidly evolving interdisciplinary field that integrates principles of electrical engineering, materials science, and biology to develop electronic interfaces capable of recording and stimulating biological activity of the human body. The conducting polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has emerged as a key bioelectronic material due to its unique properties, processing versatility, and biocompatibility. This work provides an overview of PEDOT:PSS-based bioelectronic interfaces and their growing potential in clinical applications. The historical development of PEDOT:PSS is first traced, highlighting its rise as one of the most successful materials in organic bioelectronics. The fundamental properties that make PEDOT:PSS particularly well-suited for bioelectronic interfaces are then examined, with a focus on how these properties can be precisely tuned through advanced processing and fabrication techniques. Both well-established micropatterned interfaces and the latest advancements in multidimensional hydrogel-based structures are discussed. Finally, cutting-edge clinical applications of bioelectronic systems that incorporate PEDOT:PSS are discussed, underscoring their potential in next-generation medical technologies. Overall, this work presents a balanced and forward-looking perspective that connects the evolution of PEDOT:PSS to its emerging role in clinically translatable bioelectronic systems.

Generative artificial intelligence (GenAI) is rapidly entering engineering workflows, raising new questions about liability, safety, and professional ethics. This study examined how 48 students across five engineering disciplines interpreted these issues in discipline-specific GenAI failure case studies created with ChatGPT-4o. Using a deductive qualitative approach, 192 written responses were coded against a 32-item taxonomy of ethical and professional considerations. Across disciplines, students consistently prioritised control and oversight and decision-making under risk and uncertainty. In contrast, no responses addressed data ownership, power and hegemony, or language fluency. Disciplinary differences were evident: mechatronic and electrical engineering students identified a broader set of considerations, including data collection and use, equity and accessibility, and environmental impacts. These findings support aligning curriculum and assessment with explicit requirements for documenting and validating the use of GenAI, designing for appropriate human oversight, and implementing discipline-specific learning activities that address data governance, equity, and environmental implications throughout the engineering lifecycle.

Interconnected microgrids are a new type of power system that interconnects multiple microgrids through tie‐lines and communications to realize coordinated control and optimized management. In many existing applications, the interconnected microgrids need a central controller to realize the scheduling of generators, energy storage systems, and flexible loads. However, each microgrid belongs to different owners, rendering the centralized control inconvenient. Thus, a novel distributed method for solving the economic dispatch problem (EDP) of interconnected microgrids is proposed in this paper. First, the EDP is reformulated to incorporate a penalty, and decomposed to subproblems for the microgrids. Then, a penalty‐based distributed economic dispatch method (PDED) is proposed accordingly for each microgrid to solve the entire problem in parallel. Rigorous theoretical analysis has been provided to guarantee the equivalence of reformulation and the convergence of PDED to optimal solutions. Simulations have also been conducted to demonstrate the effectiveness and advantages over existing methods. © 2025 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

Amidst the global drive toward carbon neutrality, the integration of large‐scale photovoltaic (PV) systems introduces significant challenges related to grid congestion. Battery energy storage systems (BESSs) are increasingly recognized as an effective solution for addressing these challenges and improving grid operations, especially under the management of grid operators. However, given the substantial investment and immobility of BESSs, determining their optimal placement and capacity while considering future PV‐deployment uncertainties is crucial. Moreover, selecting locations that satisfy grid constraints and offer multifunctional contributions is desirable. One promising approach is to select sites where the voltage impact of battery charging and discharging is minimal, which is expected to enhance BESS flexibility in output regulation. Therefore, this paper considers multiple PV‐deployment cases to simulate high PV penetration that induces grid congestion in distribution networks, and evaluates optimal BESS sites—selected from candidates satisfying operational constraints—based on voltage margins relative to the acceptable range. Additionally, the study examines the interplay between optimal BESS positioning, the distribution of load and PV systems, and overall power‐flow dynamics. Numerical simulations using a rural feeder model from CREST 126‐feeder model are used to quantitatively assess the impact of BESS sites on voltage margin while satisfying constrains. © 2025 The Author(s). IEEJ Transactions on Electrical and Electronic Engineering published by Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

This study proposes a method for real‐time monitoring of muscle activity applied in posture recognition by detecting changes in surface muscle pressure (SMP), a specialized form of force myography (FMG) focused on air pressure differential transduction. A monitoring system mainly consists of a pressure cuff, a spherical airbag, and a micro air pressure differential sensor. First, a physical model of the monitoring device was constructed, and a corresponding physical device was made. The device was verified and calibrated by electromyography and using an electronic digital angle ruler. Then, a real‐time data acquisition system with multiple micro pressure differential sensors was designed and manufactured. This system was integrated with the monitoring device to form a complete pressure‐based FMG posture recognition system for achieving dual‐channel high‐precision real‐time monitoring of muscle activity. The effectiveness and feasibility of the proposed method were verified through human–machine interaction experiment. © 2025 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.