Search Results (380)

Conventional piezoelectric transducers suffer from stringent coupling demands and poor environmental robustness, limiting their utility for defect detection in the flat steel of down conductors in grounding grids. To overcome this, this study presents a Lamb wave excitation source based on magnetostriction. A mechanism model of the excitation source is established by analyzing the coupling among coil-driven electromagnetic excitation, magnetostrictive deformation, mechanical loading, and Lamb wave propagation in flat steel. The excitation source configuration and magnetization scheme are designed according to the geometric features of the down conductor. The experimental results show that, under pulsed current excitation, the magnetostrictive material produces a transient mechanical response, injecting disturbances into the flat steel and thereby enabling Lamb wave detection. The proposed source is compact and robust, showing strong potential for field applications. This study provides a novel active guided-wave solution for defect detection in the flat steel of down conductors and lays a foundation for subsequent signal analysis and engineering practice. Full article

Deinterleaving of radar signals is an important issue in processing radiolocation data as a part of the analysis of complex electromagnetic signal environments. The introduction contains a draft of radiolocation signal deinterleaving. The authors began with a high-level view of contemporary challenges in radar signal processing and concluded with the genesis of the signals deinterleaving problem and its technical details. A chronicle of the Hypergeometrical Divide (HypGD) algorithm, describing important stages of its development, and a synthesis of knowledge from scientific reports on the examined method were also presented. The aim of this article is to define the performance of the HypGD algorithm adapted to the deinterleaving of radiolocation signals. The research focused on evaluating the clustering performance of the adapted HypGD algorithm, including its ability to determine groups corresponding to emission source types and to support the analysis of radar pulses in complex signal environments. The authors referred to recent publications in the field of radar signal deinterleaving to systematize the current state of knowledge in this area. A detailed, systematic review of significant works on the HypGD method and its applications was provided. The research used real, anonymized data. The results allowed the formulation of conclusions that contribute to the current state of knowledge. For the first time, the effectiveness of the HypGD algorithm adapted to the deinterleaving of radiolocation signals through pulse clustering has been demonstrated. Full article

Magnetic fields (MFs) represent an emerging modality in cancer therapy, encompassing static, low-frequency, pulsed, and nanoparticle-mediated alternating fields. These interventions have demonstrated the capacity to modulate proliferation, apoptosis, ferroptosis, migration, and epithelial-to-mesenchymal transition (EMT) in tumor cells, often through reactive oxygen species (ROS) modulation, ion channel regulation, membrane receptor dynamics, and lysosomal membrane permeabilization. Magnetic nanoparticle hyperthermia (MHT) has reached clinical application, showing promising outcomes in glioblastoma and prostate cancer, while pulsed electromagnetic fields (PEMFs) and magneto-mechanical approaches are under preclinical investigation. The mechanistic diversity of MFs allows synergistic combination with chemotherapy, radiotherapy, and immunotherapy. However, parameter sensitivity, field standardization, and long-term safety remain challenges. Here, we review mechanistic insights, signaling pathways, and experimental and clinical evidence for MF-based cancer therapies, highlighting translational potential and the need for rigorous optimization to realize clinical efficacy. Full article

Physical energy-based therapies are non-invasive adjunctive interventions that deliver mechanical, electromagnetic, light, or radiofrequency/thermal energy to tissues with the aim of reducing symptoms and improving tolerance of active rehabilitation. Osteoarthritis (OA) is a heterogeneous whole-joint disorder in which cartilage degeneration, subchondral bone remodeling, synovitis, peri-articular tissue dysfunction, neuromuscular impairment, and pain sensitization may interact to produce pain, stiffness, and activity restriction. As conservative therapy for OA, education, progressive therapeutic exercise, weight management when indicated, and self-management remain the core of care. Nevertheless, some patients cannot fully participate in exercise because of pain, fear of movement, load intolerance, comorbidity, or limited access to supervised rehabilitation. This narrative review synthesizes evidence published mainly between 2016 and 2026 for extracorporeal shock wave therapy (ESWT), photobiomodulation/low-level laser therapy (PBMT/LLLT), pulsed electromagnetic field therapy (PEMF), transfer energy capacitive and resistive/capacitive–resistive electric transfer (TECAR/CRET) therapy, body weight support and aquatic unloading strategies, and mechanosonic vibration therapies. The available literature suggests that ESWT and PBMT/LLLT may provide short- to mid-term pain and function benefits in selected patients with knee OA when parameters are aligned with evidence-supported dosing windows. PEMF and vibration therapies show promising but less consistent effects because protocols, devices, sham conditions, and populations vary. TECAR/CRET and unloading approaches are best interpreted as enabling tools that may reduce guarding, improve walking tolerance, or increase the quality of therapeutic exercise, rather than stand-alone disease-modifying treatments. Current national and society guidelines consistently prioritize exercise, education, and weight management; most of the modalities reviewed here are absent from guidelines or are supported only indirectly, which justifies cautious wording and individualized use. A practical application model is, therefore, time-limited and goal-oriented: identify the barrier to rehabilitation, select a modality with a plausible mechanism and published protocol, monitor pain and functional response, and discontinue the modality if it does not improve participation in active care. Full article

Designing an ultrashort, fast-rising high-power microwave (HPM) system requires an antenna that simultaneously provides ultrawideband (UWB) operation, high gain, and megawatt-level power handling under strict size, weight, and power (SWaP) constraints. To meet these requirements, this paper proposes an improved UWB HPM antenna that integrates a graded partial dielectric transformer (PDT) with a Koshelev-type combined antenna. The graded PDT improves impedance matching and field continuity by smoothing the dielectric-to-free-space transition, thereby alleviating a key bandwidth limitation of conventional combined antennas. Through iterative simulation, low-cost fabrication, and experimental validation, the proposed design achieves a 2.8x bandwidth enhancement, increasing the measured fractional bandwidth from 53% to 148%, with S11 < −10 dB from 0.5 to 3.0 GHz and with an additional −10 dB operating band from 3.5 to 4.4 GHz. Simulations predict a peak gain value of 15 dBi at 2.1 GHz. High-voltage pulsed tests (9–10 kV, 500 ps rise time) confirm robust operation, with radiated electric fields exceeding 10 kV/m at 1 m and no observable breakdown. The lightweight 3D-printed PLA structure (197 g) provides a scalable solution for directed-energy and electromagnetic-pulse applications. Full article

Aiming at the problems with traditional transformer winding deformation detection, requiring power outages, low signal-to-noise ratios for online monitoring, and insufficient feature extraction, this paper proposes a live monitoring and intelligent diagnosis method based on pulse-coupled injection. At the hardware level, a semi-ring capacitive coupling sensor is developed and designed, which realizes non-contact injection of high-frequency pulse signals and high-SNR extraction without a power outage. The reliability of the system under complex working conditions is verified by field experiments on multiple actual 110 kV transformers. At the algorithm level, an innovative MSCNN–Transformer–PGA deep composite model fused with prior electromagnetic physical knowledge is constructed and combined with the transformer equivalent circuit model. The model uses a multi-scale convolution to extract local details of frequency response signals, adopts Transformer to establish the global sequence dependence, and introduces a Physics-Guided Attention mechanism (PGA) to adaptively focus on the key fault physical frequency bands. The experimental results show that the proposed method effectively overcomes electromagnetic noise interference, and the fault classification accuracy of single-modal pulse frequency response data reaches 97.6%, providing a high-precision online monitoring solution for the safe operation and maintenance of transformers. Full article

A recently proposed tensor–scalar extension of gravity coupled to extended Aharonov–Bohm electrodynamics admits one-variable traveling reductions in which a longitudinal electromagnetic scalar mode $S={\partial }_{\mu }{A}^{\mu }$ couples nonlinearly to gravitational scalars. In the weak-field regime outside sources, a one-dimensional traveling ansatz depending on $\xi =x-vt$ reduces the field equations to a coupled autonomous ODE system. The mathematical core of the reduction is a singular Newton-type equation whose classical mechanics counterpart is known; the novelty here lies in its derivation from the scalar–tensor/Aharonov–Bohm field system, in the physically motivated normalization of the traveling-wave families, and in the resulting phase–space interpretation for source-generated pulse selection. We provide a systematic classification of all admissible initial data and of the corresponding maximal solutions, distinguishing repulsive/attractive regimes and subcritical/critical/supercritical behaviors through a normalized parameter map. In particular, attractive branches may reach the singularity in finite time with a universal collision exponent $2/3$, while escaping branches exhibit asymptotically uniform motion with a computable logarithmic correction. Finally, we construct a numerical atlas of representative trajectories and validate the computations by cross-checking direct time integration against numerical inversion of the implicit quadrature, together with energy-defect diagnostics. Full article

Pulsed electromagnetic fields (PEMFs) may exert antimicrobial effects, which could be relevant both in medical applications and as a contributing factor in electro-disinfection processes. This study was designed to evaluate their impact on the viability of Pseudomonas aeruginosa (ATCC 27853). Experiments were performed in three independent biological replicates, each with three technical replicates per group. Groups 1–3 served as controls and were not exposed to PEMFs. Groups 4–6, 7–9, and 10–12 were exposed to PEMFs of 40, 60, and 80 µT, respectively, for 4, 8, and 24 h using a cylindrical copper solenoid coil. Bacterial viability was assessed via colony-forming unit (CFU) counts, and log₁₀ CFU/mL values were reported. Transmission electron microscopy (TEM) was used to examine structural changes in bacterial cells. PEMF exposure significantly reduced P. aeruginosa viability, with magnetic field strength (p < 0.001), exposure time (p < 0.01), and their interaction (p < 0.05) showing significant effects. Post hoc analysis revealed that higher field strengths, particularly 80 µT after 24 h, produced the greatest reduction in CFU counts, whereas 40 µT showed no significant difference compared to controls (p > 0.05). TEM images demonstrated pronounced degeneration and structural damage in PEMF-exposed bacterial cells. PEMF exposure reduced CFU counts in an intensity and duration-dependent manner. While a dose-related trend is suggested, limited experimental conditions preclude definitive conclusions, and findings should be interpreted cautiously due to the in vitro design. Full article

In this article, the motion control of ferromagnetic particles through varying a non-invasive magnetic field is addressed. Within an experimental test bench, three experiments are proposed to verify motion control, which consist of control of the distance between electromagnets, retention of particles over the flow, and manipulation of the direction of particle flow at a “Y”-type bifurcation emulating an “OR” gate. At each experimental stage, instrumented test benches were integrated with current, distance, and flow sensors, enabling measurement and feedback of the system’s physical variables. These benches were configured using pulse-width-modulation (PWM) and Proportional–Integral–Derivative (PID) controllers to regulate the current supplied to the electromagnets and, thereby, control the intensity of the induced electromagnetic field according to the requirements of each experiment. Different study cases were defined to analyze the operational limits of the system by varying the current influencing the electromagnetic field and the configuration of the electromagnets. The results describe the response of the magnetic field, the induced force, and the behavior of the suspended particles under each condition, providing elements to characterize the performance of the electromagnetic system in operational scenarios and contributing to the understanding of the phenomena associated with the non-invasive manipulation of ferromagnetic particles by means of controlled magnetic fields. Full article

A physical and mathematical model is proposed that takes into account the sequential interaction of electromagnetic, temperature, and mechanical fields to assess the thermostressed state of an electroconductive body and predict its load-bearing capacity under the action of an external non-stationary electromagnetic field. Initial-boundary problems are formulated to determine the parameters of the electromagnetic field, temperature, dynamic thermoelastic stresses, and their intensities in a long, solid, non-ferromagnetic electroconductive cylinder. Based on the Huber–von Mises criterion, an assessment of the load-bearing capacity of this cylinder is proposed. A numerical analysis of Joule heat, ponderomotive force, temperature, components of the dynamic stress tensor, and their intensities in a solid stainless-steel cylinder under the action of an amplitude-modulated radio pulse is performed. The limiting values of the amplitude–frequency characteristics and the duration of the electromagnetic action, at which the cylinder under consideration retains its load-bearing capacity as a structural element, have been established. Full article

Background and Objectives: Knee osteoarthritis (KOA) is a major cause of global disability. The efficacy of a non-invasive treatment, pulsed electromagnetic field (PEMF) therapy, remains debated. This systematic review and meta-analysis evaluate PEMF’s effectiveness on KOA, exploring the influence of device parameters. Materials and Methods: We systematically searched PubMed, Embase, and the Cochrane Library for randomized controlled trials (RCTs) from 2015 to 2025. Nine RCTs with a total of 457 patients were included. Primary outcomes were pain (Visual Analog Scale—VAS) and function (Western Ontario and McMaster Universities Osteoarthritis Index—WOMAC). Data were pooled using a random-effects model with subgroup analyses based on PEMF amplitude and frequency. Results: No significant improvement in VAS pain or total WOMAC scores was found at one month. However, time-dependent effects were observed. WOMAC-pain improved significantly at 18–21 days (MD = −1.63, 95% CI: −2.43 to −0.82, I² = 28%) but not at one month. Conversely, WOMAC-stiffness (MD = −1.11, 95% CI: −1.386 to −0.85, I² = 0%) and daily activity (MD = −3.39, 95% CI: −4.81 to −1.97, I² = 0%) improved significantly only at the one-month. Objective functional measures did not improve, and the overall risk of bias across studies was high. The efficacy of PEMF is also influenced by the amplitude and frequency. Conclusions: PEMF efficacy for KOA is nuanced, with benefits dependent on timing and device parameters. High frequency gives fast pain relief; high amplitude builds function. Though statistically significant, these improvements may not reach thresholds for clinical meaningfulness. Significant heterogeneity in treatment protocols is a major barrier to clear conclusions. Standardized, large-scale RCTs are needed to determine optimal parameters and confirm PEMF’s clinical role. Full article

Low-frequency pulsed magnetic fields (LFPMFs) are a recently developed modality for managing pain and promoting wound healing. The term LFPMF is used to describe low-intensity fields in wound and tissue studies, and is referred to as magnetic peripheral nerve stimulation (mPNS) in pain-related studies. The recent clearance of the first mPNS device for treating pain due to diabetic neuropathy by the FDA marks a watershed event in the clinical acceptance of these modalities. In addition to being within the frequency range of 0.5–100 Hz, the use of electromagnetic fields rather than electrical current, which dissipates in tissues, results in several therapeutic advantages of magnetic fields. These fields permeate tissues and affect a larger area. Full article

The widespread commercialization of wireless chargers for electric vehicles generally suffers from one main problem, which is the perfect alignment between the two coils, leading to a decrease in mutual inductance, which causes a drop in magnetic coupling and even a failure to transfer power. To address this persistent problem, this work proposes a comprehensive and integrated method for optimizing the coils and control architecture for reliable and safe battery charging. To address the challenges of a complex, nonlinear design space and the need for misalignment-tolerant geometries, we employ a memetic algorithm (MA) that hybridizes Particle Swarm Optimization (PSO) for broad global exploration with Mesh Adaptive Direct Search (MADS) for precise local refinement. This combination effectively avoids poor local solutions—a limitation of standalone PSO or GA approaches reported in recent studies—while efficiently converging to coil geometries that maintain strong magnetic coupling under misalignment. After the coils have been designed, electromagnetic validation is tested using finite element analysis (FEA), which allows the magnetic field distribution to be evaluated, as well as the coupling coefficient under different scenarios of misalignment and variation in the air gap between the ground side and the vehicle side. At the same time, a comprehensive control strategy for the primary side of the system has been developed. This control method ensures power management on the primary side, enabling system interoperability for charging multiple types of vehicles, as well as reducing vehicle weight for greater range. All this is combined with an innovative pulsed current charging method, chosen for its advantages in terms of thermal stability, ensuring safe and efficient recharging that is mindful of battery health. Simulation and experimental validation demonstrate that the proposed framework maintains stable wireless power transfer and achieves over 87% DC–DC efficiency under lateral misalignments up to 100 mm, fully complying with SAE J2954 alignment tolerance requirements. Full article

Background: Diabetic foot ulcers (DFUs) are considered a prevalent complication of diabetes mellitus, frequently accompanied with compromised peripheral circulation, slower healing, as well as high risk of infection in addition to risk of amputation. Additional treatments that enhance microvascular perfusion and lessen plantar pressure may accelerate the healing process. This study was carried out to examine the impact of pulsed electromagnetic field (EMF) therapy as well as customized silicone gel insoles in terms of peripheral circulation in addition to vascular indices in patients with DFUs. Methods: A randomized, controlled clinical trial, including sixty-six adults diagnosed with type II diabetes as well as plantar DFUs (Wagner grade I–II) were divided into three groups (n = 22 each): Group A was given low-frequency electromagnetic field therapy (15–50 Hz, 2–5 mT, 30 min, three times per week for 8 weeks), Group B was given a customized silicone gel insoles produced for ulcer offloading, and Group C (control) was given conventional physiotherapy along with wound care. Peripheral microcirculation as well as tissue perfusion were the primary outcomes, and they were measured using Laser Doppler Flowmetry (LDF), Photoplethysmography (PPG), in addition to the Toe–Brachial Index (TBI). The secondary outcome included the Ankle–Brachial Pressure Index (ABPI). A blinded assessor measured the outcomes at the beginning of the study, after the intervention (week 8), and again after the follow-up (week 16). Results: EMF therapy significantly improved LDF (baseline: 45.2 ± 6.5 PU; week 8: 62.5 ± 7.2 PU), PPG (0.42 ± 0.08 mV to 0.68 ± 0.10 mV), TBI (0.64 ± 0.07 to 0.82 ± 0.08), and ABPI (0.88 ± 0.06 to 0.97 ± 0.05) compared with insoles and controls (p < 0.001, partial η² 0.25–0.37). The insole group exhibited moderate enhancements, whereas the control group demonstrated minor changes. Between-group analyses showed substantial differences in favor of EMF therapy across all measured variables (F = 13.5–19.9, p < 0.001). Improvements continued at the 8-week follow-up. Conclusions: Patients with DFUs who receive EMF therapy experience a significant improvement in their peripheral microcirculation, tissue perfusion, as well as vascular indices. This is more effective than just mechanical offloading, and custom insoles offer extra benefits by redistributing pressure. Combining EMF therapy with regular DFU care may speed up healing and lower the risk of problems. Additional research should investigate the efficacy of combined EMF as well as off-loading interventions and their long-term outcomes. Full article

Electromagnetic field-based stimulation has emerged as a promising noninvasive approach for enhancing bone fracture healing. Beyond conventional pulsed electromagnetic field (PEMF) therapies employing spatially uniform fields, dielectrophoretic-force-based (DEPF) stimulation exploits electromagnetic field non-uniformities to induce localized interactions to enhance fracture healing. However, the thermal behavior associated with DEPF-driven PEMF exposure in the presence of metallic orthopedic implants remains largely unexplored. In this study, the thermal response of tissue-like tibia phantoms with and without metallic implants is investigated using an integrated experimental and numerical framework. A custom-designed conical coil is employed to generate non-uniform DEPF excitation capable of affecting the fracture site. Surface temperature evolution is measured using infrared thermal imaging, while electromagnetic power absorption is quantified through specific absorption rate (SAR)-based thermal measurement coupled with a bio-heat formulation. Anatomically realistic tibia phantoms reconstructed from computed tomography data are fabricated via a 3D printer to represent clinically relevant fracture configurations. Experimental results show that the metallic implant exhibits a rapid temperature increase of approximately $0.4 °\mathrm{C}$ within the first few minutes of exposure, followed by thermal stabilization, corresponding to an effective absorbed power of ${\mathrm{SAR}}_{\mathrm{eff},\mathrm{implant}}\approx 2.2 \mathrm{W}/\mathrm{kg}$ inferred from the initial temperature slope. In contrast, the non-conductive resin phantom displays a temperature rise of only $0.05 °\mathrm{C}$ over the same interval, yielding ${\mathrm{SAR}}_{\mathrm{eff},\mathrm{resin}}\approx 0.8 \mathrm{W}/\mathrm{kg}$. These findings demonstrate that implant-related eddy-current losses dominate localized heating under DEPF excitation, while tissue-like media remain weakly affected. This work provides SAR-based experimental evaluation of DEPF stimulation in implanted tibia fracture models, offering new insight into implant-induced electromagnetic heating and its implications for the safety and optimization of DEPF-based bone-healing therapies. Full article