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26 pages, 553 KiB  
Systematic Review
Financial Education and Personal Finance: A Systematic Review of Evidence, Context, and Implications from the Spanish Language Academic Literature in Latin America
by Elena Jesús Alvarado-Cáceres, Luz Maribel Vásquez-Vásquez and Víctor Hugo Fernández-Bedoya
J. Risk Financial Manag. 2025, 18(8), 455; https://doi.org/10.3390/jrfm18080455 - 15 Aug 2025
Abstract
The growing complexity of financial markets, driven by globalization and digitalization, has increased the need for individuals to make informed financial decisions. In this context, financial education and personal finance have become crucial areas of study. This systematic review aimed to identify and [...] Read more.
The growing complexity of financial markets, driven by globalization and digitalization, has increased the need for individuals to make informed financial decisions. In this context, financial education and personal finance have become crucial areas of study. This systematic review aimed to identify and analyze the existing scientific evidence on these topics, determine the countries contributing to the literature, and extract key conclusions and lessons. A comprehensive search was conducted across the Scopus, Scielo, and La Referencia databases using keywords in Spanish. The initial query yielded 97 documents, which were filtered using seven inclusion and exclusion criteria, resulting in a final sample of 19 relevant articles. The reviewed studies highlight that financial education is a key factor in promoting economic well-being, reducing over-indebtedness, supporting entrepreneurship, and enhancing social inclusion. The effectiveness of financial education depends on equitable access to information, the use of digital tools, tailored approaches for diverse populations, and systematic program evaluation. The findings suggest that collaborative efforts between governments, educational institutions, and the financial sector are necessary to develop inclusive and practical financial education strategies, particularly for vulnerable populations. Financial education must be approached as a continuous, adaptive process to effectively respond to evolving economic challenges. Full article
(This article belongs to the Special Issue The New Horizons of Global Financial Literacy)
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16 pages, 964 KiB  
Article
Intersection Between Eco-Anxiety and Lexical Labels: A Study on Mental Health in Spanish-Language Digital Media
by Alicia Figueroa-Barra, David Guerrero-Mardones, Camila Vargas-Castillo, Luis Millalonco-Martínez, Angel Roco-Videla, Emmanuel Méndez and Sergio Flores-Carrasco
Behav. Sci. 2025, 15(8), 1102; https://doi.org/10.3390/bs15081102 - 14 Aug 2025
Viewed by 131
Abstract
Background: Eco-anxiety and solastalgia are psychological responses to environmental degradation and climate change. This study examines how these concepts are represented in Spanish-language digital media, considering both emotional dimensions and the profiles of content producers. Methods: We conducted an inductive qualitative content analysis [...] Read more.
Background: Eco-anxiety and solastalgia are psychological responses to environmental degradation and climate change. This study examines how these concepts are represented in Spanish-language digital media, considering both emotional dimensions and the profiles of content producers. Methods: We conducted an inductive qualitative content analysis of 120 Spanish-language items (online news articles and selected posts from digital platforms) published between October 2023 and March 2024. Items were identified using a Boolean search strategy and initially filtered by LIWC to detect high emotional-and-anxiety term density; final coding followed grounded-theory procedures, resulting in four thematic categories. Results: The most frequent theme was environmental activism (41%), followed by catastrophic thinking (29%), coping strategies (25%), and loss of meaningful places (6%). Among content producers, citizen participants represented 40%, youth activists 25%, and scientists 15%. Digital media function both as sources of anxiety-inducing content and as spaces for awareness-raising and support. Conclusions: While eco-anxiety is not a clinical diagnosis, it exerts a significant psychological impact—particularly on youth and vulnerable groups. Spanish-language digital platforms play an ambivalent role, amplifying distress yet enabling resilience and collective action. Future interventions should leverage these channels to foster environmental awareness, emotional resilience, and civic engagement. Full article
(This article belongs to the Special Issue Mental Health and the Natural Environment)
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36 pages, 9430 KiB  
Article
Numerical Method for Internal Structure and Surface Evaluation in Coatings
by Tomas Kačinskas and Saulius Baskutis
Inventions 2025, 10(4), 71; https://doi.org/10.3390/inventions10040071 - 13 Aug 2025
Viewed by 110
Abstract
This study introduces a MATrix LABoratory (MATLAB, version R2024b, update 1 (24.2.0.2740171))-based automated system for the detection and measurement of indication areas in coated surfaces, enhancing the accuracy and efficiency of quality control processes in metal, polymeric and thermoplastic coatings. The developed code [...] Read more.
This study introduces a MATrix LABoratory (MATLAB, version R2024b, update 1 (24.2.0.2740171))-based automated system for the detection and measurement of indication areas in coated surfaces, enhancing the accuracy and efficiency of quality control processes in metal, polymeric and thermoplastic coatings. The developed code identifies various indication characteristics in the image and provides numerical results, assesses the size and quantity of indications and evaluates conformity to ISO standards. A comprehensive testing method, involving non-destructive penetrant testing (PT) and radiographic testing (RT), allowed for an in-depth analysis of surface and internal porosity across different coating methods, including aluminum-, copper-, polytetrafluoroethylene (PTFE)- and polyether ether ketone (PEEK)-based materials. Initial findings had a major impact on indicating a non-homogeneous surface of obtained coatings, manufactured using different technologies and materials. Whereas researchers using non-destructive testing (NDT) methods typically rely on visual inspection and manual counting, the system under study automates this process. Each sample image is loaded into MATLAB and analyzed using the Image Processing Tool, Computer Vision Toolbox, Statistics and Machine Learning Toolbox. The custom code performs essential tasks such as image conversion, filtering, boundary detection, layering operations and calculations. These processes are integral to rendering images with developed indications according to NDT method requirements, providing a detailed visual and numerical representation of the analysis. RT also validated the observations made through surface indication detection, revealing either the absence of hidden defects or, conversely, internal porosity correlating with surface conditions. Matrix and graphical representations were used to facilitate the comparison of test results, highlighting more advanced methods and materials as the superior choice for achieving optimal mechanical and structural integrity. This research contributes to addressing challenges in surface quality assurance, advancing digital transformation in inspection processes and exploring more advanced alternatives to traditional coating technologies and materials. Full article
(This article belongs to the Section Inventions and Innovation in Advanced Manufacturing)
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31 pages, 3840 KiB  
Review
Application of Deep Learning in the Phase Processing of Digital Holographic Microscopy
by Wenbo Jiang, Lirui Liu and Yun Bu
Photonics 2025, 12(8), 810; https://doi.org/10.3390/photonics12080810 - 13 Aug 2025
Viewed by 111
Abstract
Digital holographic microscopy (DHM) provides numerous advantages, such as noninvasive sample analysis, real-time dynamic detection, and three-dimensional (3D) reconstruction, making it a valuable tool in fields such as biomedical research, cell mechanics, and environmental monitoring. To achieve more accurate and comprehensive imaging, it [...] Read more.
Digital holographic microscopy (DHM) provides numerous advantages, such as noninvasive sample analysis, real-time dynamic detection, and three-dimensional (3D) reconstruction, making it a valuable tool in fields such as biomedical research, cell mechanics, and environmental monitoring. To achieve more accurate and comprehensive imaging, it is crucial to capture detailed information on the microstructure and 3D morphology of samples. Phase processing of holograms is essential for recovering phase information, thus making it a core component of DHM. Traditional phase processing techniques often face challenges, such as low accuracy, limited robustness, and poor generalization. Recently, with the ongoing advancements in deep learning, addressing phase processing challenges in DHM has become a key research focus. This paper provides an overview of the principles behind DHM and the characteristics of each phase processing step. It offers a thorough analysis of the progress and challenges of deep learning methods in areas such as phase retrieval, filtering, phase unwrapping, and distortion compensation. The paper concludes by exploring trends, such as ultrafast 3D holographic reconstruction, high-throughput holographic data analysis, multimodal data fusion, and precise quantitative phase analysis. Full article
(This article belongs to the Special Issue Holographic Information Processing)
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14 pages, 2652 KiB  
Article
Optimized Multi-Antenna MRC for 16-QAM Transmission in a Photonics-Aided Millimeter-Wave System
by Rahim Uddin, Weiping Li and Jianjun Yu
Sensors 2025, 25(16), 5010; https://doi.org/10.3390/s25165010 - 13 Aug 2025
Viewed by 117
Abstract
This work presents an 80 Gbps photonics-aided millimeter-wave (mm Wave) wireless communication system employing 16-Quadrature Amplitude Modulation (16-QAM) and a 1 × 2 single-input multiple-output (SIMO) architecture with maximum ratio combining (MRC) to achieve robust 87.5 GHz transmission over 4.6 km. By utilizing [...] Read more.
This work presents an 80 Gbps photonics-aided millimeter-wave (mm Wave) wireless communication system employing 16-Quadrature Amplitude Modulation (16-QAM) and a 1 × 2 single-input multiple-output (SIMO) architecture with maximum ratio combining (MRC) to achieve robust 87.5 GHz transmission over 4.6 km. By utilizing polarization-diverse optical heterodyne generation and spatial diversity reception, the system enhances spectral efficiency while addressing the low signal-to-noise ratio (SNR) and channel distortions inherent in long-haul links. A blind equalization scheme combining the constant modulus algorithm (CMA) and decision-directed least mean squares (DD-LMS) filtering enables rapid convergence and suppresses residual inter-symbol interference, effectively mitigating polarization drift and phase noise. The experimental results demonstrate an SNR gain of approximately 3 dB and a significant bit error rate (BER) reduction with MRC compared to single-antenna reception, along with improved SNR performance in multi-antenna configurations. The synergy of photonic mm Wave generation, adaptive spatial diversity, and pilot-free digital signal processing (DSP) establishes a robust framework for high-capacity wireless fronthaul, overcoming atmospheric attenuation and dynamic impairments. This approach highlights the viability of 16-QAM in next-generation ultra-high-speed networks (6G/7G), balancing high data rates with resilient performance under channel degradation. Full article
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17 pages, 2534 KiB  
Article
Modeling Recommender Systems Using Disease Spread Techniques
by Peixiong He, Libo Sun, Xian Gao, Yi Zhou and Xiao Qin
Information 2025, 16(8), 687; https://doi.org/10.3390/info16080687 - 13 Aug 2025
Viewed by 156
Abstract
Recommender systems on digital platforms profoundly influence user behavior through content dissemination, and their diffusion process is similar to the spreading mechanism of infectious diseases to some extent. In this paper, we use a network-based susceptibility-infection (SI) model to model the propagation dynamics [...] Read more.
Recommender systems on digital platforms profoundly influence user behavior through content dissemination, and their diffusion process is similar to the spreading mechanism of infectious diseases to some extent. In this paper, we use a network-based susceptibility-infection (SI) model to model the propagation dynamics of recommended content, and systematically compare the differences in propagation efficiency among three recommendation strategies based on popularity, collaborative filtering, and content. We constructed scale-free user networks based on real-world clickstream data and dynamically adapted the SI model to reflect the realistic scenario of user engagement decay over time. To enhance the understanding of the recommendation process, we further simulate the visualization changes of the propagation process to show how the content spreads among users. The experimental results show that collaborative filtering performs superior in the initial dissemination, but its dissemination effect decays rapidly over time and is weaker than the other two methods. This study provides new ideas for modeling and understanding recommender systems from an epidemiological perspective. Full article
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16 pages, 1707 KiB  
Article
An Overview of Analog and Digital RF Generator Techniques, Suitable for Space-Based AOTF Applications
by Jurgen Vanhamel
Appl. Sci. 2025, 15(15), 8739; https://doi.org/10.3390/app15158739 - 7 Aug 2025
Viewed by 230
Abstract
The use of Acousto-Optical Tunable Filters (AOTFs) is well known in ground- and space-based applications. These devices are used in several optical instruments and payloads for monitoring and other purposes. To make use of the filter capability of the AOTF, a dedicated Radio [...] Read more.
The use of Acousto-Optical Tunable Filters (AOTFs) is well known in ground- and space-based applications. These devices are used in several optical instruments and payloads for monitoring and other purposes. To make use of the filter capability of the AOTF, a dedicated Radio Frequency (RF) chain, consisting of an RF generator and RF amplifier, is needed. An RF generator can be designed in several ways. However, the design of these steering devices for space applications comes with several difficulties and limitations. The mechanical stress due to shock and vibration, the temperature variation, as well as the vacuum environment and radiation levels in which these devices have to perform limits the selection of possible techniques. This paper aims at giving an in-depth overview of space-qualified RF generator techniques using Commercial-Off-The-Shelf available components that usable in the harsh environment of space and applicable in driving AOTFs. Several analog as well as digital generator principles are discussed, substantiated by test results. Full article
(This article belongs to the Special Issue Recent Advances in Space Instruments and Sensing Technology)
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20 pages, 105195 KiB  
Article
Filter-Based Tchebichef Moment Analysis for Whole Slide Image Reconstruction
by Keun Woo Kim, Wenxian Jin and Barmak Honarvar Shakibaei Asli
Electronics 2025, 14(15), 3148; https://doi.org/10.3390/electronics14153148 - 7 Aug 2025
Viewed by 248
Abstract
In digital pathology, accurate diagnosis and prognosis critically depend on robust feature representation of Whole Slide Images (WSIs). While deep learning offers powerful solutions, its “black box” nature presents significant challenges to clinical interpretability and widespread adoption. Handcrafted features offer interpretability, yet orthogonal [...] Read more.
In digital pathology, accurate diagnosis and prognosis critically depend on robust feature representation of Whole Slide Images (WSIs). While deep learning offers powerful solutions, its “black box” nature presents significant challenges to clinical interpretability and widespread adoption. Handcrafted features offer interpretability, yet orthogonal moments, particularly Tchebichef moments (TMs), remain underexplored for WSI analysis. This study introduces TMs as interpretable, efficient, and scalable handcrafted descriptors for WSIs, alongside a novel two-dimensional digital filter architecture designed to enhance numerical stability and hardware compatibility during TM computation. We conducted a comprehensive reconstruction analysis using H&E-stained WSIs from the MIDOG++ dataset to evaluate TM effectiveness. Our results demonstrate that lower-order TMs accurately reconstruct both square and rectangular WSI patches, with performance stabilising beyond a threshold moment order, confirmed by SNIRE, SSIM, and BRISQUE metrics, highlighting their capacity to retain structural fidelity. Furthermore, our analysis reveals significant computational efficiency gains through the use of pre-computed polynomials. These findings establish TMs as highly promising, interpretable, and scalable feature descriptors, offering a robust alternative for computational pathology applications that prioritise both accuracy and transparency. Full article
(This article belongs to the Special Issue Image Fusion and Image Processing)
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30 pages, 6195 KiB  
Article
Digital Inspection Technology for Sheet Metal Parts Using 3D Point Clouds
by Jian Guo, Dingzhong Tan, Shizhe Guo, Zheng Chen and Rang Liu
Sensors 2025, 25(15), 4827; https://doi.org/10.3390/s25154827 - 6 Aug 2025
Viewed by 256
Abstract
To solve the low efficiency of traditional sheet metal measurement, this paper proposes a digital inspection method for sheet metal parts based on 3D point clouds. The 3D point cloud data of sheet metal parts are collected using a 3D laser scanner, and [...] Read more.
To solve the low efficiency of traditional sheet metal measurement, this paper proposes a digital inspection method for sheet metal parts based on 3D point clouds. The 3D point cloud data of sheet metal parts are collected using a 3D laser scanner, and the topological relationship is established by using a K-dimensional tree (KD tree). The pass-through filtering method is adopted to denoise the point cloud data. To preserve the fine features of the parts, an improved voxel grid method is proposed for the downsampling of the point cloud data. Feature points are extracted via the intrinsic shape signatures (ISS) algorithm and described using the fast point feature histograms (FPFH) algorithm. After rough registration with the sample consensus initial alignment (SAC-IA) algorithm, an initial position is provided for fine registration. The improved iterative closest point (ICP) algorithm, used for fine registration, can enhance the registration accuracy and efficiency. The greedy projection triangulation algorithm optimized by moving least squares (MLS) smoothing ensures surface smoothness and geometric accuracy. The reconstructed 3D model is projected onto a 2D plane, and the actual dimensions of the parts are calculated based on the pixel values of the sheet metal parts and the conversion scale. Experimental results show that the measurement error of this inspection system for three sheet metal workpieces ranges from 0.1416 mm to 0.2684 mm, meeting the accuracy requirement of ±0.3 mm. This method provides a reliable digital inspection solution for sheet metal parts. Full article
(This article belongs to the Section Industrial Sensors)
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18 pages, 1239 KiB  
Article
A Digitally Controlled Adaptive Current Interface for Accurate Measurement of Resistive Sensors in Embedded Sensing Systems
by Jirapong Jittakort and Apinan Aurasopon
J. Sens. Actuator Netw. 2025, 14(4), 82; https://doi.org/10.3390/jsan14040082 - 4 Aug 2025
Viewed by 315
Abstract
This paper presents a microcontroller-based technique for accurately measuring resistive sensors over a wide dynamic range using an adaptive constant current source. Unlike conventional voltage dividers or fixed-current methods—often limited by reduced resolution and saturation when sensor resistance varies across several decades—the proposed [...] Read more.
This paper presents a microcontroller-based technique for accurately measuring resistive sensors over a wide dynamic range using an adaptive constant current source. Unlike conventional voltage dividers or fixed-current methods—often limited by reduced resolution and saturation when sensor resistance varies across several decades—the proposed system dynamically adjusts the excitation current to maintain optimal Analog-to-Digital Converter (ADC) input conditions. The measurement circuit employs a fixed reference resistor and an inverting amplifier configuration, where the excitation current is generated by one or more pulse-width modulated (PWM) signals filtered through low-pass RC networks. A microcontroller selects the appropriate PWM channel to ensure that the output voltage remains within the ADC’s linear range. To support multiple sensors, an analog switch enables sequential measurements using the same dual-PWM current source. The full experimental implementation uses four op-amps to support modularity, buffering, and dual-range operation. Experimental results show accurate measurement of resistances from 1 kΩ to 100 kΩ, with maximum relative errors of 0.15% in the 1–10 kΩ range and 0.33% in the 10–100 kΩ range. The method provides a low-cost, scalable, and digitally controlled solution suitable for embedded resistive sensing applications without the need for high-resolution ADCs or programmable gain amplifiers. Full article
(This article belongs to the Section Actuators, Sensors and Devices)
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25 pages, 394 KiB  
Article
SMART DShot: Secure Machine-Learning-Based Adaptive Real-Time Timing Correction
by Hyunmin Kim, Zahid Basha Shaik Kadu and Kyusuk Han
Appl. Sci. 2025, 15(15), 8619; https://doi.org/10.3390/app15158619 - 4 Aug 2025
Viewed by 244
Abstract
The exponential growth of autonomous systems demands robust security mechanisms that can operate within the extreme constraints of real-time embedded environments. This paper introduces SMART DShot, a groundbreaking machine learning-enhanced framework that transforms the security landscape of unmanned aerial vehicle motor control systems [...] Read more.
The exponential growth of autonomous systems demands robust security mechanisms that can operate within the extreme constraints of real-time embedded environments. This paper introduces SMART DShot, a groundbreaking machine learning-enhanced framework that transforms the security landscape of unmanned aerial vehicle motor control systems through seamless integration of adaptive timing correction and real-time anomaly detection within Digital Shot (DShot) communication protocols. Our approach addresses critical vulnerabilities in Electronic Speed Controller (ESC) interfaces by deploying four synergistic algorithms—Kalman Filter Timing Correction (KFTC), Recursive Least Squares Timing Correction (RLSTC), Fuzzy Logic Timing Correction (FLTC), and Hybrid Adaptive Timing Correction (HATC)—each optimized for specific error characteristics and attack scenarios. Through comprehensive evaluation encompassing 32,000 Monte Carlo test iterations (500 per scenario × 16 scenarios × 4 algorithms) across 16 distinct operational scenarios and PolarFire SoC Field-Programmable Gate Array (FPGA) implementation, we demonstrate exceptional performance with 88.3% attack detection rate, only 2.3% false positive incidence, and substantial vulnerability mitigation reducing Common Vulnerability Scoring System (CVSS) severity from High (7.3) to Low (3.1). Hardware validation on PolarFire SoC confirms practical viability with minimal resource overhead (2.16% Look-Up Table utilization, 16.57 mW per channel) and deterministic sub-10 microsecond execution latency. The Hybrid Adaptive Timing Correction algorithm achieves 31.01% success rate (95% CI: [30.2%, 31.8%]), representing a 26.5% improvement over baseline approaches through intelligent meta-learning-based algorithm selection. Statistical validation using Analysis of Variance confirms significant performance differences (F(3,1996) = 30.30, p < 0.001) with large effect sizes (Cohen’s d up to 4.57), where 64.6% of algorithm comparisons showed large practical significance. SMART DShot establishes a paradigmatic shift from reactive to proactive embedded security, demonstrating that sophisticated artificial intelligence can operate effectively within microsecond-scale real-time constraints while providing comprehensive protection against timing manipulation, de-synchronization, burst interference, replay attacks, coordinated multi-channel attacks, and firmware-level compromises. This work provides essential foundations for trustworthy autonomous systems across critical domains including aerospace, automotive, industrial automation, and cyber–physical infrastructure. These results conclusively demonstrate that ML-enhanced motor control systems can achieve both superior security (88.3% attack detection rate with 2.3% false positives) and operational performance (31.01% timing correction success rate, 26.5% improvement over baseline) simultaneously, establishing SMART DShot as a practical, deployable solution for next-generation autonomous systems. Full article
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16 pages, 1651 KiB  
Article
Modular Pipeline for Text Recognition in Early Printed Books Using Kraken and ByT5
by Yahya Momtaz, Lorenza Laccetti and Guido Russo
Electronics 2025, 14(15), 3083; https://doi.org/10.3390/electronics14153083 - 1 Aug 2025
Viewed by 427
Abstract
Early printed books, particularly incunabula, are invaluable archives of the beginnings of modern educational systems. However, their complex layouts, antique typefaces, and page degradation caused by bleed-through and ink fading pose significant challenges for automatic transcription. In this work, we present a modular [...] Read more.
Early printed books, particularly incunabula, are invaluable archives of the beginnings of modern educational systems. However, their complex layouts, antique typefaces, and page degradation caused by bleed-through and ink fading pose significant challenges for automatic transcription. In this work, we present a modular pipeline that addresses these problems by combining modern layout analysis and language modeling techniques. The pipeline begins with historical layout-aware text segmentation using Kraken, a neural network-based tool tailored for early typographic structures. Initial optical character recognition (OCR) is then performed with Kraken’s recognition engine, followed by post-correction using a fine-tuned ByT5 transformer model trained on manually aligned line-level data. By learning to map noisy OCR outputs to verified transcriptions, the model substantially improves recognition quality. The pipeline also integrates a preprocessing stage based on our previous work on bleed-through removal using robust statistical filters, including non-local means, Gaussian mixtures, biweight estimation, and Gaussian blur. This step enhances the legibility of degraded pages prior to OCR. The entire solution is open, modular, and scalable, supporting long-term preservation and improved accessibility of cultural heritage materials. Experimental results on 15th-century incunabula show a reduction in the Character Error Rate (CER) from around 38% to around 15% and an increase in the Bilingual Evaluation Understudy (BLEU) score from 22 to 44, confirming the effectiveness of our approach. This work demonstrates the potential of integrating transformer-based correction with layout-aware segmentation to enhance OCR accuracy in digital humanities applications. Full article
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21 pages, 12325 KiB  
Article
Inspection of Damaged Composite Structures with Active Thermography and Digital Shearography
by João Queirós, Hernâni Lopes, Luís Mourão and Viriato dos Santos
J. Compos. Sci. 2025, 9(8), 398; https://doi.org/10.3390/jcs9080398 - 1 Aug 2025
Viewed by 336
Abstract
This study comprehensively compares the performance of two non-destructive testing (NDT) techniques—active thermography (AT) and digital shearography (DS)—for identifying various damage types in composite structures. Three distinct composite specimens were inspected: a carbon-fiber-reinforced polymer (CFRP) plate with flat-bottom holes, an aluminum honeycomb core [...] Read more.
This study comprehensively compares the performance of two non-destructive testing (NDT) techniques—active thermography (AT) and digital shearography (DS)—for identifying various damage types in composite structures. Three distinct composite specimens were inspected: a carbon-fiber-reinforced polymer (CFRP) plate with flat-bottom holes, an aluminum honeycomb core sandwich plate with a circular skin-core disbond, and a CFRP plate with two low-energy impacts damage. The research highlights the significant role of post-processing methods in enhancing damage detectability. For AT, algorithms such as fast Fourier transform (FFT) for temperature phase extraction and principal component thermography (PCT) for identifying significant temperature components were employed, generally making anomalies brighter and easier to locate and size. For DS, a novel band-pass filtering approach applied to phase maps, followed by summing the filtered maps, remarkably improved the visualization and precision of damage-induced anomalies by suppressing background noise. Qualitative image-based comparisons revealed that DS consistently demonstrated superior performance. The sum of DS filtered phase maps provided more detailed and precise information regarding damage location and size compared to both pulsed thermography (PT) and lock-in thermography (LT) temperature phase and amplitude. Notably, DS effectively identified shallow flat-bottom holes and subtle imperfections that AT struggled to clearly resolve, and it provided a more comprehensive representation of the impacts damage location and extent. This enhanced capability of DS is attributed to the novel phase map filtering approach, which significantly improves damage identification compared to the thermogram post-processing methods used for AT. Full article
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23 pages, 5770 KiB  
Article
Assessment of Influencing Factors and Robustness of Computable Image Texture Features in Digital Images
by Diego Andrade, Howard C. Gifford and Mini Das
Tomography 2025, 11(8), 87; https://doi.org/10.3390/tomography11080087 - 31 Jul 2025
Viewed by 222
Abstract
Background/Objectives: There is significant interest in using texture features to extract hidden image-based information. In medical imaging applications using radiomics, AI, or personalized medicine, the quest is to extract patient or disease specific information while being insensitive to other system or processing variables. [...] Read more.
Background/Objectives: There is significant interest in using texture features to extract hidden image-based information. In medical imaging applications using radiomics, AI, or personalized medicine, the quest is to extract patient or disease specific information while being insensitive to other system or processing variables. While we use digital breast tomosynthesis (DBT) to show these effects, our results would be generally applicable to a wider range of other imaging modalities and applications. Methods: We examine factors in texture estimation methods, such as quantization, pixel distance offset, and region of interest (ROI) size, that influence the magnitudes of these readily computable and widely used image texture features (specifically Haralick’s gray level co-occurrence matrix (GLCM) textural features). Results: Our results indicate that quantization is the most influential of these parameters, as it controls the size of the GLCM and range of values. We propose a new multi-resolution normalization (by either fixing ROI size or pixel offset) that can significantly reduce quantization magnitude disparities. We show reduction in mean differences in feature values by orders of magnitude; for example, reducing it to 7.34% between quantizations of 8–128, while preserving trends. Conclusions: When combining images from multiple vendors in a common analysis, large variations in texture magnitudes can arise due to differences in post-processing methods like filters. We show that significant changes in GLCM magnitude variations may arise simply due to the filter type or strength. These trends can also vary based on estimation variables (like offset distance or ROI) that can further complicate analysis and robustness. We show pathways to reduce sensitivity to such variations due to estimation methods while increasing the desired sensitivity to patient-specific information such as breast density. Finally, we show that our results obtained from simulated DBT images are consistent with what we see when applied to clinical DBT images. Full article
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34 pages, 1156 KiB  
Systematic Review
Mathematical Modelling and Optimization Methods in Geomechanically Informed Blast Design: A Systematic Literature Review
by Fabian Leon, Luis Rojas, Alvaro Peña, Paola Moraga, Pedro Robles, Blanca Gana and Jose García
Mathematics 2025, 13(15), 2456; https://doi.org/10.3390/math13152456 - 30 Jul 2025
Viewed by 357
Abstract
Background: Rock–blast design is a canonical inverse problem that joins elastodynamic partial differential equations (PDEs), fracture mechanics, and stochastic heterogeneity. Objective: Guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol, a systematic review of mathematical methods for geomechanically informed [...] Read more.
Background: Rock–blast design is a canonical inverse problem that joins elastodynamic partial differential equations (PDEs), fracture mechanics, and stochastic heterogeneity. Objective: Guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol, a systematic review of mathematical methods for geomechanically informed blast modelling and optimisation is provided. Methods: A Scopus–Web of Science search (2000–2025) retrieved 2415 records; semantic filtering and expert screening reduced the corpus to 97 studies. Topic modelling with Bidirectional Encoder Representations from Transformers Topic (BERTOPIC) and bibliometrics organised them into (i) finite-element and finite–discrete element simulations, including arbitrary Lagrangian–Eulerian (ALE) formulations; (ii) geomechanics-enhanced empirical laws; and (iii) machine-learning surrogates and multi-objective optimisers. Results: High-fidelity simulations delimit blast-induced damage with ≤0.2 m mean absolute error; extensions of the Kuznetsov–Ram equation cut median-size mean absolute percentage error (MAPE) from 27% to 15%; Gaussian-process and ensemble learners reach a coefficient of determination (R2>0.95) while providing closed-form uncertainty; Pareto optimisers lower peak particle velocity (PPV) by up to 48% without productivity loss. Synthesis: Four themes emerge—surrogate-assisted PDE-constrained optimisation, probabilistic domain adaptation, Bayesian model fusion for digital-twin updating, and entropy-based energy metrics. Conclusions: Persisting challenges in scalable uncertainty quantification, coupled discrete–continuous fracture solvers, and rigorous fusion of physics-informed and data-driven models position blast design as a fertile test bed for advances in applied mathematics, numerical analysis, and machine-learning theory. Full article
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