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Search Results (1,085)

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22 pages, 2210 KB  
Article
Extreme Fast Charging Station for Multiple Vehicles with Sinusoidal Currents at the Grid Side and SiC-Based dc/dc Converters
by Dener A. de L. Brandao, Thiago M. Parreiras, Igor A. Pires and Braz J. Cardoso Filho
World Electr. Veh. J. 2026, 17(4), 215; https://doi.org/10.3390/wevj17040215 - 18 Apr 2026
Viewed by 83
Abstract
Extreme fast charging (XFC) infrastructure is becoming increasingly necessary as the number of electric vehicles continues to grow. However, deploying such stations introduces several challenges related to power quality and compliance with regulatory standards. This work presents an alternative XFC station designed for [...] Read more.
Extreme fast charging (XFC) infrastructure is becoming increasingly necessary as the number of electric vehicles continues to grow. However, deploying such stations introduces several challenges related to power quality and compliance with regulatory standards. This work presents an alternative XFC station designed for charging multiple vehicles while ensuring low harmonic distortion in the grid currents, without the need for sinusoidal filters, by employing the Zero Harmonic Distortion (ZHD) converter. The proposed system offers galvanic isolation for each charging interface and supports additional functionalities, including the integration of Distributed Energy Resources (DERs) and the provision of ancillary services. These features are enabled through the combination of a bidirectional grid-connected active front-end operating at low switching frequency with high-frequency silicon carbide (SiC)-based dc/dc converters on the vehicle side. Hardware-in-the-loop (HIL) simulation results demonstrate a total demand distortion (TDD) of 1.12% for charging scenarios involving both 400 V and 800 V battery systems, remaining within the limits specified by IEEE 519-2022. Full article
(This article belongs to the Special Issue Power and Energy Systems for E-Mobility, 2nd Edition)
23 pages, 4010 KB  
Article
Aerodynamic Transport Characteristics of Irregular Harmonic Particles at Finite Reynolds Numbers
by Carlos Castang, Daniela Chavarro and Santiago Laín
Processes 2026, 14(8), 1255; https://doi.org/10.3390/pr14081255 - 15 Apr 2026
Viewed by 331
Abstract
This study presents the characterization of the aerodynamic forces and moments acting on irregular particles of prescribed sphericity, generated through truncated spherical harmonic expansions and immersed in a uniform flow at intermediate Reynolds numbers (1 ≤ Re ≤ 200). Particle-resolved direct numerical simulations [...] Read more.
This study presents the characterization of the aerodynamic forces and moments acting on irregular particles of prescribed sphericity, generated through truncated spherical harmonic expansions and immersed in a uniform flow at intermediate Reynolds numbers (1 ≤ Re ≤ 200). Particle-resolved direct numerical simulations are conducted using the commercial solver ANSYS Fluent to quantify the statistical behavior of drag, transverse lift, and transverse torque coefficients, along with the corresponding force and moment components, as a function of Reynolds number. Deviations from spherical geometry are shown to induce persistent flow asymmetries, leading to finite transverse lift and torque components even under uniform inflow conditions, effects that cannot be captured by models based on dynamically equivalent spheres. For a sphericity of 0.93, represented by six particle realizations, irregular particles exhibit mean drag values approximately 10% higher than those of spheres with the same equivalent diameter. In addition, both the magnitude and the statistical characteristics of the aerodynamic coefficients are strongly modulated by the combined effects of particle shape irregularity and flow regime. These results provide new insight into the role of geometric complexity in fluid–particle interactions and represent a step forward toward improved predictive capability beyond conventional spherical and quasi-spherical approximations. Furthermore, the present findings provide a physically grounded basis for the development of fluid–particle interaction models for irregular particles, suitable for implementation within Euler–Lagrange simulations of turbulent dispersed flows. Full article
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14 pages, 335 KB  
Article
Demographic and Clinical Correlates of Body Mass Index in Older Age Bipolar Disorder: Results from the GAGE-BD Project
by Carol K. Chan, Kasia G. Rothenberg, Farren B. S. Briggs, Amulya Mallu, Nicole M. Fiorelli, Osvaldo P. Almeida, Kürşat Altınbaş, Vicent Balanzá-Martinez, Izabela G. Barbosa, Hilary P. Blumberg, Peijun Chen, Leon Flicker, Ariel Gildengers, Bartholomeus C. M. Haarman, Federica Klaus, Beny Lafer, Paula V. Nunes, Andrew T. Olagunju, Stephen O. Oluwaniyi, Melis Orhan, Regan E. Patrick, Edith Pomarol-Clotet, Joaquim Radua, Soham Rej, Jair C. Saores, Antonio L. Teixeira, Shangying Tsai, Sonia L. L. Vidal-Rubio, Eduard Vieta, Sara L. Weisenbach, Lisa T. Eyler, Annemiek Dols and Martha Sajatovicadd Show full author list remove Hide full author list
Medicina 2026, 62(4), 761; https://doi.org/10.3390/medicina62040761 - 15 Apr 2026
Viewed by 216
Abstract
Background and Objectives: There are known associations between bipolar disorder and obesity, but it has not been well characterized in older adults with bipolar disorder (OABD). This study aims to examine body mass index (BMI) and its clinical correlations in OABD. Materials [...] Read more.
Background and Objectives: There are known associations between bipolar disorder and obesity, but it has not been well characterized in older adults with bipolar disorder (OABD). This study aims to examine body mass index (BMI) and its clinical correlations in OABD. Materials and Methods: A secondary analysis was conducted using data from the Global Aging and Geriatric Experiments in Bipolar Disorder (GAGE-BD) project, an international harmonized dataset of OABD cohorts. To examine the relationship between BMI and clinical characteristics (e.g., sex, psychiatric history, symptom severity, medication use, comorbidities), multivariable linear regression and multinomial logistic regression models with random effect for study cohort were used, with BMI as a continuous and as an ordinal (underweight vs. healthy weight vs. overweight vs. obese) dependent variable, respectively. Results: Of 1,226 OABD participants with BMI data, 405 (33.0%) were classified as overweight (BMI 25–29.99) and 462 (37.7%) as obese (BMI > 30). In linear regression models, higher BMI was associated with younger age, higher number of somatic comorbidities, and anticonvulsant use, while lower BMI was associated with lithium use. In logistic regression models, obesity was associated with cardiovascular comorbidity, musculoskeletal comorbidity and endocrine comorbidity. Conclusions: A high proportion of individuals with OABD are overweight or obese. Several demographic and clinical correlations of higher BMI were found, including younger age, higher number of medical comorbidities and anticonvulsant use. Clinicians should monitor and manage weight changes and associated comorbidities, and promote lifestyle and health interventions to minimize the risk of negative health outcomes associated with high BMI. Full article
17 pages, 827 KB  
Systematic Review
Diagnostic Accuracy of MUM1 (IRF4) Immunohistochemistry in Chronic Endometritis: A Systematic Review and Bayesian Meta-Analysis
by Ana Maria Mihoci, Demetra Socolov, Eduard Cristian Mihoci, Loredana Maria Toma, Andreea Ioana Pruteanu and Răzvan Vladimir Socolov
Diagnostics 2026, 16(8), 1167; https://doi.org/10.3390/diagnostics16081167 - 15 Apr 2026
Viewed by 312
Abstract
Background/Objectives: Chronic endometritis (CE) is an underrecognized inflammatory disorder associated with infertility, recurrent pregnancy loss, and implantation failure. CD138 immunohistochemistry is widely used to detect endometrial plasma cells; however, background epithelial staining and interobserver variability may limit diagnostic precision. MUM1 (IRF4), a nuclear [...] Read more.
Background/Objectives: Chronic endometritis (CE) is an underrecognized inflammatory disorder associated with infertility, recurrent pregnancy loss, and implantation failure. CD138 immunohistochemistry is widely used to detect endometrial plasma cells; however, background epithelial staining and interobserver variability may limit diagnostic precision. MUM1 (IRF4), a nuclear transcription factor expressed in plasma cells, has emerged as a potential complementary marker. We aimed to systematically evaluate the diagnostic performance of MUM1 immunohistochemistry relative to CD138-based histopathologic reference frameworks for chronic endometritis using a Bayesian meta-analytic framework. Methods: We conducted a systematic review and diagnostic test accuracy meta-analysis in accordance with PRISMA 2020 and PRISMA-DTA guidelines. MEDLINE, Embase, Scopus, and CENTRAL were searched from inception to 28 February 2026. Studies assessing MUM1 immunohistochemistry against predefined histopathologic reference frameworks for CE were eligible. Risk of bias was evaluated using QUADAS-2. A bivariate Bayesian random-effects model was applied to jointly estimate pooled sensitivity, specificity, likelihood ratios, and diagnostic odds ratio (DOR). Results: Six studies (n = 1574 women) were included in the qualitative synthesis, and four provided sufficient 2 × 2 data for quantitative pooling. The pooled sensitivity of MUM1 was 0.876 (95% credible interval (CrI): 0.536–0.976), and the pooled specificity was 0.853 (95% CrI: 0.653–0.930). The pooled positive likelihood ratio was 5.83 (95% CrI: 2.18–12.04), and the negative likelihood ratio was 0.15 (95% CrI: 0.03–0.56), corresponding to a DOR of 40.27 (95% CrI: 5.04–254.59). Credible intervals were wide, reflecting statistical uncertainty related to the limited number of studies and heterogeneity in diagnostic thresholds. Conclusions: MUM1 (IRF4) immunohistochemistry demonstrates potentially favorable comparative diagnostic performance relative to CD138-based reference frameworks, although substantial uncertainty remains due to limited and heterogeneous evidence. As an adjunctive nuclear marker, MUM1 may support histopathologic assessment of chronic endometritis; however, prospective head-to-head studies using harmonized diagnostic criteria and predefined plasma cell thresholds are required before routine implementation can be firmly recommended. Full article
(This article belongs to the Section Pathology and Molecular Diagnostics)
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22 pages, 4020 KB  
Article
From Failure Analysis to Manufacturing-Informed Reliability: Comparative FMEA of EHB and EMB Brake-by-Wire Systems
by Lucian-Gabriel Petrescu, Maria-Cătălina Petrescu and Cătălin-Daniel Constantinescu
Machines 2026, 14(4), 422; https://doi.org/10.3390/machines14040422 - 10 Apr 2026
Viewed by 337
Abstract
This study presents a comparative Failure Modes and Effects Analysis (FMEA) of electro-hydraulic braking (EHB) and electro-mechanical braking (EMB) systems within brake-by-wire architectures. The analysis integrates both the conventional Risk Priority Number (RPN) approach and the AIAG–VDA Action Priority (AP) methodology, enabling a [...] Read more.
This study presents a comparative Failure Modes and Effects Analysis (FMEA) of electro-hydraulic braking (EHB) and electro-mechanical braking (EMB) systems within brake-by-wire architectures. The analysis integrates both the conventional Risk Priority Number (RPN) approach and the AIAG–VDA Action Priority (AP) methodology, enabling a structured comparison of risk prioritization strategies applied to identical failure modes. A consistent system-level framework is developed to harmonize severity (S), occurrence (O), and detection (D) assessments across both architectures, allowing direct evaluation of methodological differences. The results demonstrate systematic divergences between RPN and AP approaches, particularly in high-severity scenarios, where AP provides more safety-oriented prioritization. The study further identifies key limitations of traditional RPN-based evaluation in safety-critical systems and highlights the advantages of rule-based prioritization frameworks. In addition, corrective measures are proposed and their impact on occurrence and detection ratings is quantified, illustrating practical pathways for risk reduction. Beyond methodological comparison, the work introduces a novel integration of reliability engineering with advanced manufacturing strategies, demonstrating how laser and plasma-based surface engineering can mitigate failure mechanisms by reducing occurrence and improving system robustness. The proposed approach establishes a conceptual and physically grounded bridge between system-level risk assessment and material-level optimization, contributing to the development of more reliable next-generation brake-by-wire systems. Full article
(This article belongs to the Section Machines Testing and Maintenance)
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15 pages, 3434 KB  
Article
Cyclic Fatigue of Rotary Versus Reciprocating Endodontic Files: An In Vitro Study of Engine-Driven Endodontic Files
by Sverre Brun, Andrine Rebni Kristoffersen, Malene Nerbøberg Solsvik, Marit Øilo and Inge Fristad
Dent. J. 2026, 14(4), 216; https://doi.org/10.3390/dj14040216 - 8 Apr 2026
Viewed by 261
Abstract
Background/Objectives: Instrument fracture remains a significant complication in endodontics. This study compared the resistance to cyclic fatigue failure between rotary and reciprocating nickel–titanium file systems, as well as differences related to file size and taper. Methods: Nineteen rotary and reciprocating file types (n [...] Read more.
Background/Objectives: Instrument fracture remains a significant complication in endodontics. This study compared the resistance to cyclic fatigue failure between rotary and reciprocating nickel–titanium file systems, as well as differences related to file size and taper. Methods: Nineteen rotary and reciprocating file types (n = 10 per group) were evaluated in three independent test series, harmonized according to file size and system. Cyclic fatigue testing was conducted using a static model with a stainless-steel artificial canal, with an internal diameter of 0.9 mm, a 75° curvature angle, and a fixed radius for each series. Files were operated using preset programs on the X-Smart Plus, Rooter X3000, and Sendoline Endo torque-controlled motors. Time to fracture was recorded digitally, and the total number of full rotations to failure was calculated. The fractured fragments were examined with scanning electron microscopy and fractographic analysis. The data were analyzed using linear models in Stata version 19, with significance set at p ≤ 0.05. Results: Reciprocating file systems demonstrated greater time-to-fracture fatigue resistance than rotary systems. However, these differences were diminished or, in some cases, eliminated when normalized to the number of complete rotations. Fractographic analysis indicated that fractures predominantly resulted from tensile stress rather than shear forces. Conclusions: Reciprocating kinematics generally enhanced fatigue resistance compared with continuous rotation. The results suggest that fatigue resistance in machine-driven nickel–titanium instruments cannot be predicted by motion type or file design alone but reflects a complex interaction between alloy composition, heat treatment, and cross-sectional geometry. Full article
(This article belongs to the Special Issue Endodontics: From Technique to Regeneration)
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14 pages, 257 KB  
Review
Unpacking the mRNA Supply Chain: Challenges and Opportunities for Global Health
by Ariane de Jesus Lopes de Abreu, Cheleka A. M. Mpande, Yang Song, Martin W. Nicholson, Claudia Nannei and Martin Friede
Vaccines 2026, 14(4), 324; https://doi.org/10.3390/vaccines14040324 - 6 Apr 2026
Viewed by 606
Abstract
The COVID-19 pandemic highlighted both the transformative potential of mRNA vaccines and the structural challenges associated with their supply chains. Unlike traditional vaccine platforms, mRNA vaccines depend on highly specialized raw materials, including plasmid DNA (pDNA), nucleotides, enzymes, and lipid nanoparticles (LNP), that [...] Read more.
The COVID-19 pandemic highlighted both the transformative potential of mRNA vaccines and the structural challenges associated with their supply chains. Unlike traditional vaccine platforms, mRNA vaccines depend on highly specialized raw materials, including plasmid DNA (pDNA), nucleotides, enzymes, and lipid nanoparticles (LNP), that are produced by a limited number of global suppliers. These dependencies, combined with platform-specific manufacturing processes and stringent cold chain requirements, introduce vulnerabilities across production, distribution, and regulatory oversight. This narrative review examines the distinctive features of mRNA vaccine supply chains and identifies key challenges and opportunities across three interconnected domains: manufacturing systems, logistics and distribution, and regulatory governance. Drawing on literature published between January 2021 and March 2026, the review synthesizes evidence on supply chain bottlenecks revealed during the COVID-19 pandemic, including upstream raw-material dependencies, limitations in manufacturing scale-up, cold chain constraints, and regulatory fragmentation. Particular attention is given to the implications of these challenges for low- and middle-income countries, where infrastructure, technical capacity, and regulatory resources may limit participation in mRNA vaccine production and deployment. The review also highlights emerging strategies to strengthen supply chain resilience, including diversification of input suppliers, development of regional manufacturing hubs, improvements in vaccine thermostability, regulatory harmonization initiatives, and the use of digital technologies for supply chain management. By integrating insights from manufacturing, logistics, and regulatory perspectives, this study contributes to a better understanding of the structural characteristics shaping mRNA vaccine supply chains and identifies priority areas for strengthening global preparedness for future health emergencies. Full article
(This article belongs to the Special Issue The Development of mRNA Vaccines)
14 pages, 1219 KB  
Article
Spatial Bias in Open Biodiversity Data: How GBIF Record Quality Shapes Conservation Analyses
by Seweryn Lipiński
Conservation 2026, 6(2), 40; https://doi.org/10.3390/conservation6020040 - 2 Apr 2026
Viewed by 323
Abstract
Open-access biodiversity repositories such as the Global Biodiversity Information Facility (GBIF) are central to contemporary conservation research, yet their heterogeneous data sources introduce quality issues and spatial sampling biases that may compromise conservation analyses. This study evaluates the spatial and taxonomic quality of [...] Read more.
Open-access biodiversity repositories such as the Global Biodiversity Information Facility (GBIF) are central to contemporary conservation research, yet their heterogeneous data sources introduce quality issues and spatial sampling biases that may compromise conservation analyses. This study evaluates the spatial and taxonomic quality of GBIF occurrence data for five protected species representing mammals and vascular plants in Central Europe. A transparent data-cleaning workflow was applied, including coordinate validation, removal of duplicate and erroneous locations, and taxonomic harmonization. Spatial sampling bias was quantified using nearest neighbor distance-based metrics, enabling comparison of clustering patterns before and after data cleaning. Raw datasets exhibited strong spatial clustering across all species, with nearest neighbor ratios (NNR) ranging from 0.06 to 0.73. Data cleaning reduced the number of retained records by approximately 15–57% and increased NNR values to 0.27–0.80, indicating the removal of extreme spatial artifacts. However, NNR values remained well below unity after cleaning, demonstrating persistent non-random spatial sampling structure related to uneven sampling effort. The strongest relative improvements were observed for plant species derived from herbarium records. These results highlight the need to distinguish between data quality errors and structural spatial bias in open biodiversity data and underscore the necessity of bias-aware methods beyond standard data-cleaning procedures in conservation analyses. Full article
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24 pages, 929 KB  
Article
Analytical and Clinical Validation of Action PharmaKitDx: A Comprehensive NGS Panel for the Identification of Pharmacogenetic Variants in Diverse Populations
by Luis Ramudo-Cela, Marta Izquierdo-García, María Dolores-Sequedo, Vicente Cubells-Perez, Sara Bernal, Pau Riera, Adriana Lasa, Laura Torres-Juan, Victor José Asensio, Iciar Martínez-López, Antonia Obrador de Hevia, Matías Morín, Miguel Ángel Moreno-Pelayo, Greta Carmona-Antoñanzas and Javier Porta Pelayo
Pharmaceuticals 2026, 19(4), 568; https://doi.org/10.3390/ph19040568 - 1 Apr 2026
Viewed by 716
Abstract
Background/Objectives: Pharmacogenomics (PGx) enables personalized therapy by identifying genetic variants that influence drug response. Despite the advantages of next-generation sequencing (NGS), few clinically validated, guideline-aligned panels comprehensively detect common, rare, and structurally complex pharmacogenetic variants. Methods: We developed and analytically validated [...] Read more.
Background/Objectives: Pharmacogenomics (PGx) enables personalized therapy by identifying genetic variants that influence drug response. Despite the advantages of next-generation sequencing (NGS), few clinically validated, guideline-aligned panels comprehensively detect common, rare, and structurally complex pharmacogenetic variants. Methods: We developed and analytically validated Action PharmaKitDx, a targeted NGS panel covering 335 pharmacogenes, including all priority genes recommended by CPIC, DPWG, and CPNDS. Performance was assessed using Coriell HapMap and GeT-RM reference materials across multiple library preparation workflows and Illumina platforms. Clinical feasibility was evaluated in 41 patient samples from diverse specialties. Results were compared with established reference methods, including PCR-based assays, STR analysis, Sanger sequencing, and whole-exome sequencing. Results: Analytical validation: More than 99% of target bases achieved ≥30× coverage. Analytical accuracy, sensitivity, specificity, and positive predictive value exceeded 99.3%, with repeatability and reproducibility >99.7%. Concordance with GeT-RM haplotypes reached 98% after star-allele harmonization. The panel accurately detected complex variants, including CYP2D6 copy-number changes and hybrid alleles. Clinical validation: Full concordance with prior genotyping was observed in clinical samples. Beyond the initial testing indication, each sample harbored a mean of six actionable variants (range 2–10). Thirty-six rare (minor allele frequency <1%) potentially actionable variants were additionally identified. Conclusions: Action PharmaKitDx demonstrates high analytical performance and broad clinical applicability, supporting its implementation as a scalable solution for comprehensive pharmacogenetic testing and precision prescribing. Full article
(This article belongs to the Special Issue Applications of Pharmacogenomics in Precision Medicine)
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21 pages, 8266 KB  
Article
Proportional–Derivative Output Feedback Vibration Control with Antiresonance for Systems with Time Delay in Actuators
by José Mário Araújo, José Ricardo Bezerra de Araújo, Nelson José Bonfim Dantas and Carlos Eduardo Trabuco Dórea
Processes 2026, 14(7), 1065; https://doi.org/10.3390/pr14071065 - 26 Mar 2026
Viewed by 433
Abstract
Active vibration control is crucial for mitigating harmful resonant vibrations in structures subjected to harmonic loads. While antiresonant (zero-placement) methods are effective for this purpose, existing state-feedback solutions require full state measurement, and output-feedback approaches often prioritize resonance assignment over direct harmonic cancellation. [...] Read more.
Active vibration control is crucial for mitigating harmful resonant vibrations in structures subjected to harmonic loads. While antiresonant (zero-placement) methods are effective for this purpose, existing state-feedback solutions require full state measurement, and output-feedback approaches often prioritize resonance assignment over direct harmonic cancellation. This work bridges this gap by proposing a novel systematic design for a proportional–derivative (PD) output-feedback controller to achieve antiresonance for second-order linear systems with a time delay in the actuators. The method first computes a homogeneous gain solution. It then leverages the parametrization of all antiresonant solutions as a constraint within a genetic algorithm optimization. The algorithm optimizes both the stability margin, characterized by an Ms-disk criterion, and the number of encirclements of the critical point (1,0) in the complex plane, as assessed by the Generalized Nyquist Stability Criterion. The proposed approach provides a practical, optimized output-feedback strategy for precise rejection of harmonic disturbances, as demonstrated through a collection of numerical examples from real-world applications. The results confirm the method’s effectiveness in synthesizing stabilizing controllers that enforce antiresonance while ensuring robust stability margins. Full article
(This article belongs to the Special Issue Stability and Optimal Control of Linear Systems)
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13 pages, 2562 KB  
Article
Regulation of the Second Harmonic Generation of High-Order Poincaré Sphere Beams Using Different Phase Matching
by Quanlan Xiao, Junsen Yan, Xiaohui Ling and Shunbin Lu
Photonics 2026, 13(4), 316; https://doi.org/10.3390/photonics13040316 - 25 Mar 2026
Viewed by 267
Abstract
High-order Poincaré sphere (HOPS) beams have attracted tremendous interest due to their complex polarization and phase characteristics. However, manipulating the second harmonics generation (SHG) of HOPS beams is still challenging. Here, we developed a vector-coupled wave model to predict petal-shaped intensity patterns and [...] Read more.
High-order Poincaré sphere (HOPS) beams have attracted tremendous interest due to their complex polarization and phase characteristics. However, manipulating the second harmonics generation (SHG) of HOPS beams is still challenging. Here, we developed a vector-coupled wave model to predict petal-shaped intensity patterns and reveal a linear correlation between petal number and topological order (n = 2 → 4). Moreover, we experimentally investigated the multidimensional regulation of SHG in HOPS beams through tailored phase-matching strategies. By employing three distinct configurations—(i) type-I phase matching, (ii) type-II phase matching, and (iii) orthogonally arranged BBO crystals based on Type-I phase matching—we establish a comprehensive framework for controlling the spatial and polarization properties of SHG in n = 2 HOPS beams. These results advance the manipulation of structured light in nonlinear optics, providing insights for optimizing applications in optical communication and polarization imaging. Full article
(This article belongs to the Special Issue Photonic Crystals: Physics and Devices, 2nd Edition)
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18 pages, 4313 KB  
Article
Analysis of a Novel Three-Port Single-Stage Bidirectional DC–AC Converter for PV-ESS-V2G System
by Chunhui Liu, Yinfu Bao, Celiang Deng, Fan Zhang, Da Wang, Haoran Chen, Wentao Ma, Feng Jiang and Min Chen
Electronics 2026, 15(7), 1360; https://doi.org/10.3390/electronics15071360 - 25 Mar 2026
Viewed by 360
Abstract
Multiport DC–AC converters are widely used in photovoltaic-energy storage–charging systems, but traditional two-stage schemes face challenges in circuit cost and efficiency improvements. To address this issue, a novel three-port single-stage DC–AC converter is proposed for grid-connected applications. The proposed converter integrates two DC [...] Read more.
Multiport DC–AC converters are widely used in photovoltaic-energy storage–charging systems, but traditional two-stage schemes face challenges in circuit cost and efficiency improvements. To address this issue, a novel three-port single-stage DC–AC converter is proposed for grid-connected applications. The proposed converter integrates two DC ports and one AC port through circuit multiplexing, eliminating the high-voltage DC bus and reducing system complexity. An unfolding bridge is employed at the AC port, and full bridge circuits are used at DC ports, reducing the number of high-frequency switches. The proposed single-stage topology inherently achieves galvanic isolation and bidirectional power conversion. To achieve accurate grid current regulation and wide-range zero-voltage-switching, a multiple-phase-shift modulation method is developed to ensure a sinusoidal current waveform. The effectiveness of the proposed converter and modulation method is verified through simulation results, demonstrating a peak efficiency of 97% and a total harmonic distortion of 2.91%. Full article
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24 pages, 3621 KB  
Article
Phase-Space Reconstruction and 2-D Fourier Descriptor Features for Appliance Classification in Non-Intrusive Load Monitoring
by Motaz Abu Sbeitan, Hussain Shareef, Madathodika Asna, Rachid Errouissi, Muhamad Zalani Daud, Radhika Guntupalli and Bala Bhaskar Duddeti
Energies 2026, 19(6), 1512; https://doi.org/10.3390/en19061512 - 18 Mar 2026
Viewed by 298
Abstract
Non-Intrusive Load Monitoring (NILM) enables appliance-level classification from aggregate electrical measurements and supports efficient energy management in smart buildings. However, the accuracy of existing NILM methods is often limited by the inability of conventional feature extraction techniques to capture nonlinear steady-state behavior. This [...] Read more.
Non-Intrusive Load Monitoring (NILM) enables appliance-level classification from aggregate electrical measurements and supports efficient energy management in smart buildings. However, the accuracy of existing NILM methods is often limited by the inability of conventional feature extraction techniques to capture nonlinear steady-state behavior. This study proposes a novel feature extraction framework for appliance classification, which integrates phase-space reconstruction (PSR) with 2-D Fourier series to derive geometry-based descriptors of appliance current waveforms. Unlike traditional signal-processing methods, the proposed approach utilizes the nonlinear geometric structure revealed by PSR and encodes it through Fourier descriptors, offering a discriminative, low-dimensional feature space suitable for classification using supervised machine learning algorithms. The method is evaluated on the high-resolution controlled single-appliance recordings from the COOLL dataset using the K-Nearest Neighbor (KNN) classifier. Extension to aggregated multi-appliance NILM scenarios would require additional stages such as event detection and load separation. Sensitivity analysis demonstrates that classification performance depends strongly on the choice of time delay and harmonic order, with optimal settings yielding an accuracy of up to 99.52% using KNN. The results confirm that larger time delays and a small number of harmonics effectively capture appliance-specific signatures. The findings highlight the effectiveness of PSR–Fourier-based geometric features as a robust alternative to conventional NILM feature extraction strategies. Full article
(This article belongs to the Special Issue Digital Engineering for Future Smart Cities)
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17 pages, 1730 KB  
Article
Optimal Implementation of Dynamical Visual Cryptography Scheme for Imaging-Based Testing of Human Visual System
by Loreta Saunoriene, Paulius Palevicius, Arvydas Gelzinis and Minvydas Ragulskis
Mathematics 2026, 14(6), 1020; https://doi.org/10.3390/math14061020 - 17 Mar 2026
Viewed by 278
Abstract
Dynamic visual cryptography (DVC) can be formulated as a discrete-time reconstruction problem for time-averaged moiré fringes generated by oscillatory transformations of periodic gratings. When implemented on digital display hardware, the continuous oscillatory motion must be realized through discrete frames, which may prevent correct [...] Read more.
Dynamic visual cryptography (DVC) can be formulated as a discrete-time reconstruction problem for time-averaged moiré fringes generated by oscillatory transformations of periodic gratings. When implemented on digital display hardware, the continuous oscillatory motion must be realized through discrete frames, which may prevent correct reconstruction of higher-order time-averaged fringes due to refresh-rate limitations. In this work, mathematical criteria are derived to ensure the reliable reconstruction of higher-order time-averaged moiré fringes under finite refresh rate constraints. Harmonic, stochastic, and rectangular temporal waveforms are examined within a unified framework based on the number of frames per oscillation period and the discrete structure of the resulting time-averaged intensity distribution. Stochastic waveforms are shown to not guaranty reproducible fringe formation. For harmonic modulation with a 240 Hz display refresh rate and a 50 Hz oscillation frequency, only four full frames per period are obtained, which is insufficient to reconstruct the third time-averaged moiré fringe requiring at least sixteen frames per period. Rectangular waveforms satisfy the derived reconstruction conditions when the pitch of the grating, the oscillation amplitude, and the resolution of the rendered grating meet explicit constraints. These results establish quantitative parameter bounds for a mathematically consistent software-based DVC implementation on digital displays. Full article
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21 pages, 783 KB  
Article
Painlevé Confluence and 1/f Phase-Locking Dynamics: A Topological Framework for Human–AI Collaboration
by Michel Planat
Mach. Learn. Knowl. Extr. 2026, 8(3), 73; https://doi.org/10.3390/make8030073 - 15 Mar 2026
Viewed by 388
Abstract
Recent work on the evaluation of large language models emphasizes that the relevant unit of intelligence is not the artificial system alone but the human–AI hybrid. In parallel, topological and dynamical models of cognition based on Painlevé equations and non-semisimple topology propose that [...] Read more.
Recent work on the evaluation of large language models emphasizes that the relevant unit of intelligence is not the artificial system alone but the human–AI hybrid. In parallel, topological and dynamical models of cognition based on Painlevé equations and non-semisimple topology propose that consciousness, intelligence, and creativity emerge from constrained long-horizon dynamics near criticality. This perspective article argues that these two research directions are deeply compatible. We show that the empirical framework for human–AI collaboration can be interpreted as a fusion process between complementary cognitive sectors: exploration (AI) and selection (human cognition). The dynamical mechanism underlying this fusion is identified with noisy phase locking between cognitive oscillators. Two independent routes to a universal 1/f spectral signature are developed: a geometric route through the WKB/Stokes analysis of Painlevé V confluence, and an arithmetic route through the Mangoldt function and harmonic interactions in phase-locked loops. We connect these results to the Bost–Connes quantum statistical model, whose phase transition at the pole of the Riemann zeta function provides an exact mathematical framework for the lock-in phase hypothesis of identity consolidation in AI systems. This synthesis suggests a unified research program for hybrid intelligence grounded in topology, dynamical systems, number theory, and real-world AI evaluation. Full article
(This article belongs to the Section Thematic Reviews)
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