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Search Results (3,046)

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21 pages, 16640 KiB  
Article
Assessment of Hammer Energy Measurement for the Standard Penetration Test (SPT) Using Pile Driving Analyzer and Kallpa Analyzer Devices in Peru
by Carmen Ortiz, Jorge Alva, José Oliden, Nelly Huarcaya, Grover Riveros and Roberto Raucana
Sensors 2025, 25(5), 1460; https://doi.org/10.3390/s25051460 - 27 Feb 2025
Viewed by 56
Abstract
Energy measurement in dynamic penetration tests is key to correctly interpreting test results and ensuring comparable geotechnical data. Although commercial devices are widely used, their high cost limits adoption in developing regions such as Peru, affecting the accuracy of soil evaluation in many [...] Read more.
Energy measurement in dynamic penetration tests is key to correctly interpreting test results and ensuring comparable geotechnical data. Although commercial devices are widely used, their high cost limits adoption in developing regions such as Peru, affecting the accuracy of soil evaluation in many geotechnical studies. In this context, this research presents an energy measurement system called Kallpa, which uses low-cost electronic components to digitize sensor signals during Standard Penetration Tests (SPTs). Kallpa employs high-resolution analog-to-digital converters (ADCs) with an advanced sampling frequency, processing and storing data via a Raspberry Pi 4 microcomputer. The sensors, including accelerometers and strain gauges, were calibrated and compared with the Pile Driving Analyzer (PDA) to validate their accuracy in the Kallpa system. This study involved sixteen Standard Penetration Tests (SPTs) conducted in various regions of Peru using donut hammers and two tests involving automatic hammers. The results demonstrate that the Kallpa system is comparable to other energy measurement devices on the market, such as the Dynamic Penetration Test (DPT), which provides accurate SPT energy measurements. The Kallpa Processor (Version 1.0) software was developed to perform data acquisition and calibration, analyzing approximately 500 hammer blows and comparing peak values with those of the Pile Driving Analyzer. The data collected by Kallpa’s sensors strongly agreed with the PDA data, validating the reliability of the device. The Energy Transfer Ratio (ETR) for manual hammers ranged from 43.5% to 68.4%, with an average of 58.9%, whereas automatic hammers presented ETR values between 82% and 87%. The correction of the N60 blow count allowed for the estimation of the relative density of soils evaluated at different depths and locations across Peru. Full article
(This article belongs to the Special Issue Sensors Technologies for Measurements and Signal Processing)
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<p>Instrumented rod for energy measurement.</p>
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<p>Location of energy measurement tests conducted by the Digital Transformation Center in Peru.</p>
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<p>Pile Dynamics measurement equipment, where the accelerometers and strain gauges are directly connected to the instrumented rod section.</p>
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<p>MCP3564 analog-to-digital converter.</p>
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<p>View of the Raspberry Pi 4.</p>
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<p>Components of the Kallpa measurement equipment.</p>
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<p>Design of the signal acquisition board.</p>
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<p>Flow diagram of the Kallpa device.</p>
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<p>Kallpa Processor software startup interface.</p>
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<p>Functional architecture of Kallpa Processor.</p>
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<p>Connection diagram of the Kallpa device.</p>
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<p>Parameter configuration of the Collect Wire window.</p>
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<p>Visualization of two acceleration signals and to deformation signals from the test carried out at UNTELS (Kallpa Processor—Version 1.0). The graph shows two sensors per magnitude, differentiated by the orange and blue colors.</p>
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<p>Top of the PDF report generated by the Kallpa Processor software: force–velocity graph.</p>
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<p>Bottom of the PDF report generated by the Kallpa Processor software: summary of energy data from the test.</p>
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<p>Calibration of the K16670 accelerometer in the Kallpa device compared to the PDA analyzer.</p>
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<p>Calibration of the strain gauge 590AW1 in the Kallpa device compared to the PDA analyzer.</p>
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<p>Calibration of the K13548 accelerometer in the Kallpa device compared to the PDA analyzer.</p>
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<p>Calibration of the strain gauge 590AW2 in the Kallpa device compared to the PDA analyzer.</p>
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<p>Comparison impacts between Pile and Kallpa: strain gauge impact.</p>
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<p>Comparison impacts between Pile and Kallpa: acceleration impact.</p>
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<p>Measured ETR (%) values as a function of depth for manual and automatic donut-type hammers. Pisco (<b>a</b>), Tumbes (<b>b</b>), Villa El Salvador manual equipment (<b>c</b>), Villa El Salvador automatic equipment (<b>d</b>), Ica (<b>e</b>), and Trujillo (<b>f</b>).</p>
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<p>Plot for a normality test of ETR values for the manual SPT (<b>a</b>); Q-Q plot (<b>b</b>).</p>
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<p>Plot for a normality test of ETR values for the automatic SPT (<b>a</b>); Q-Q plot (<b>b</b>).</p>
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<p>Measured ETR (%) values as a function of depth for manual donut hammers (<b>a</b>) and automatic hammers (<b>b</b>).</p>
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25 pages, 2823 KiB  
Article
Digital Technologies in Food Supply Chain Waste Management: A Case Study on Sustainable Practices in Smart Cities
by Hajar Fatorachian, Hadi Kazemi and Kulwant Pawar
Sustainability 2025, 17(5), 1996; https://doi.org/10.3390/su17051996 - 26 Feb 2025
Viewed by 115
Abstract
This study explores how digital technologies and data analytics can transform urban waste management in smart cities by addressing systemic inefficiencies. Integrating perspectives from the Resource-Based View, Socio-Technical Systems Theory, Circular Economy Theory, and Institutional Theory, the research examines sustainability, operational efficiency, and [...] Read more.
This study explores how digital technologies and data analytics can transform urban waste management in smart cities by addressing systemic inefficiencies. Integrating perspectives from the Resource-Based View, Socio-Technical Systems Theory, Circular Economy Theory, and Institutional Theory, the research examines sustainability, operational efficiency, and resilience in extended supply chains. A case study of Company A and its demand-side supply chain with Retailer B highlights key drivers of waste, including overstocking, inventory mismanagement, and inefficiencies in transportation and promotional activities. Using a mixed-methods approach, the study combines quantitative analysis of operational data with advanced statistical techniques and machine learning models. Key data sources include inventory records, sales forecasts, promotional activities, waste logs, and IoT sensor data collected over a two-year period. Machine learning techniques were employed to uncover complex, non-linear relationships between waste drivers and waste generation. A waste-type-specific emissions framework was used to assess environmental impacts, while IoT-enabled optimization algorithms helped improve logistics efficiency and reduce waste collection costs. Our findings indicate that the adoption of IoT and AI technologies significantly reduced waste by enhancing inventory control, optimizing transportation, and improving supply chain coordination. These digital innovations also align with circular economy principles by minimizing resource consumption and emissions, contributing to broader sustainability and resilience goals in urban environments. The study underscores the importance of integrating digital solutions into waste management strategies to foster more sustainable and efficient urban supply chains. While the research is particularly relevant to the food production and retail sectors, it also provides valuable insights for policymakers, urban planners, and supply chain stakeholders. By bridging theoretical frameworks with practical applications, this study demonstrates the potential of digital technologies to drive sustainability and resilience in smart cities. Full article
(This article belongs to the Section Sustainable Transportation)
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<p>Proposed theoretical framework for smart waste management.</p>
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<p>Distribution of waste by source, and reductions achieved.</p>
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<p>Comparative analysis of waste levels before and after digital intervention.</p>
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<p>Weekly waste optimization using IoT.</p>
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<p>Correlation between overstocking and waste generation.</p>
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<p>Reduction in carbon emissions through optimized collection.</p>
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<p>Predictive model accuracy for waste generation.</p>
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13 pages, 220 KiB  
Review
Challenges in Applying Multimodal Imaging Technologies to Quantify In Vivo Glycogen and Intramuscular Fat in Livestock
by Tharcilla I. R. C. Alvarenga, Peter McGilchrist, Marianne D. Keller and David W. Pethick
Foods 2025, 14(5), 784; https://doi.org/10.3390/foods14050784 - 25 Feb 2025
Viewed by 214
Abstract
Predicting meat quality, especially dark, firm and dry meat, as well as muscle fat prior to slaughter, presents a challenge in practice. Medical as well as high-frequency ultrasound applications can be utilized to predict body composition and meat quality aspects. Ultrasounds are non-invasive, [...] Read more.
Predicting meat quality, especially dark, firm and dry meat, as well as muscle fat prior to slaughter, presents a challenge in practice. Medical as well as high-frequency ultrasound applications can be utilized to predict body composition and meat quality aspects. Ultrasounds are non-invasive, rapid-to-operate in vivo and show high correlations to the animal production traits being estimated. Farm animal ultrasounds are used to predict intramuscular fat content in the beef cattle industry. Challenges are identified in applying ultrasound technology to detect glycogen content in farm animals due to a wide range of fat, muscle and water composition. Other technologies and methods are reported in this literature review to overcome issues in the practicability and accuracy of ultrasound technology when estimating muscle glycogen levels in cattle. The discussion of other tools such as hyperspectral imaging, microwave sensor technology and digital infrared thermal imaging were addressed because of their superior accuracy in estimating moisture and fat components. Full article
(This article belongs to the Special Issue Factors Impacting Meat Product Quality: From Farm to Table)
15 pages, 4917 KiB  
Article
Evaluation of the Performance of Static Mixers in 3D Printed Millireactors Using Integrated pH-Sensitive Films
by Marijan-Pere Marković, Elizabeta Forjan, Petar Kassal, Anđela Nosić and Domagoj Vrsaljko
Appl. Sci. 2025, 15(5), 2488; https://doi.org/10.3390/app15052488 - 25 Feb 2025
Viewed by 285
Abstract
The aim of this research was to prepare pH sensor films based on litmus using the sol–gel method with tetraethoxysilane (TEOS) and phenyltrimethoxysilane (PTMS) as precursors. The pH sensor film was then applied to millireactors to evaluate its performance on the intricate geometries [...] Read more.
The aim of this research was to prepare pH sensor films based on litmus using the sol–gel method with tetraethoxysilane (TEOS) and phenyltrimethoxysilane (PTMS) as precursors. The pH sensor film was then applied to millireactors to evaluate its performance on the intricate geometries of static mixers commonly found in millireactor designs. Millireactors were made from Formlabs High Temp resin using stereolithography (SLA) and from Anycubic Basic resin using digital light processing (DLP) technology. The performance of the pH sensor films was evaluated by tracking color changes in the pH sensor films and analyzing RGB (red, green, blue) and hue values through a smartphone application. The experiment involved mixing solutions with different pH values at varying flow rates within the millireactor channels. Furthermore, along with analyzing the hue values, characterization techniques involved measuring contact angles with water and diiodomethane. A film combining a litmus indicator with titanium dioxide (TiO2) displayed a color change within one minute and maintained this color throughout the study, confirming its reusability. Sensor films exhibited excellent reversibility (RSD = 2.4–3.3%) and stability. The findings demonstrate that the pH-sensitive films perform robustly across varying geometries, paving the way for their integration into advanced millireactor systems with static mixers and continuous chemical monitoring within Industry 4.0. Full article
(This article belongs to the Section Additive Manufacturing Technologies)
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<p>(<b>a</b>) Design of a tubular millireactor, (<b>b</b>) sketch of the tubular millireactor with dimensions in millimeters.</p>
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<p>(<b>a</b>) Design of a millireactor with static mixers, (<b>b</b>) sketch of the millireactor with static mixers with dimensions in millimeters.</p>
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<p>Experimental setup with two syringe pumps connected to a millireactor.</p>
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<p>Graphical representation of the dependance of RGB and hue values on the pH of the solution that the test plates were immersed in for 5 min.</p>
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<p>Millireactors made from (<b>a</b>) Anycubic Basic resin and (<b>b</b>) High Temp resin 300 s after the introduction of acid and base with marked points of analysis.</p>
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<p>Graphical representation of the dependence of the <span class="html-italic">H</span> values on time, with error bars, in the middle of the millireactor made of Anycubic Basic resin without static mixers in acid and base flow exchange cycles ((A)—acid flow is dominant, (B)—base flow is dominant).</p>
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<p>Graphical representation of the dependence of <span class="html-italic">H</span> values on time, with error bars, in the middle of the millireactor with static mixers made of Anycubic Basic resin in acid (A) and base (B) flow exchange cycles.</p>
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<p>Graphical representation of the <span class="html-italic">H</span> values’ dependence on time, with error bars, in the middle of the millireactor made of High Temp resin during cycles of alternating acid (A) and base (B) flow.</p>
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<p>Graphical representation of the <span class="html-italic">H</span> values’ dependence on time, with error bars, in the middle of the millireactor with static mixers made of High Temp resin during cycles of alternating acid (A) and base (B) flow.</p>
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20 pages, 10408 KiB  
Article
Integration of Real Signals Acquired Through External Sensors into RoboDK Simulation of Robotic Industrial Applications
by Cozmin Cristoiu and Andrei Mario Ivan
Sensors 2025, 25(5), 1395; https://doi.org/10.3390/s25051395 - 25 Feb 2025
Viewed by 141
Abstract
Ensuring synchronization between real-world sensor data and industrial robotic simulations remains a critical challenge in digital twin and virtual commissioning applications. This study proposes an innovative method for integrating real sensor signals into RoboDK simulations, bridging the gap between virtual models and real-world [...] Read more.
Ensuring synchronization between real-world sensor data and industrial robotic simulations remains a critical challenge in digital twin and virtual commissioning applications. This study proposes an innovative method for integrating real sensor signals into RoboDK simulations, bridging the gap between virtual models and real-world dynamics. The proposed system utilizes an Arduino-based data acquisition module and a custom Python script to establish real-time communication between physical sensors and RoboDK’s simulation environment. Unlike traditional simulations that rely on predefined simulated signals or manually triggered virtual inputs, our approach enables dynamic real-time interactions based on live sensor data. The system supports both analog and digital signals and is validated through latency measurements, demonstrating an average end-to-end delay of 23.97 ms. These results confirm the feasibility of real sensor integration into RoboDK, making the system adaptable to various industrial applications. This framework provides a scalable foundation for researchers and engineers to develop enhanced simulation environments that more accurately reflect real industrial conditions. Full article
(This article belongs to the Special Issue Dynamics and Control System Design for Robot Manipulation)
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<p>Implementation stages of a robotic industrial application: <b>up</b>—standard process design approach; <b>down</b>—virtual commissioning approach (as presented by Eguti et al. [<a href="#B19-sensors-25-01395" class="html-bibr">19</a>]).</p>
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<p>Software-in-the-loop and hardware-in-the-loop concepts, together with the model-in-the-loop approach, as presented by Ullrich et al. [<a href="#B29-sensors-25-01395" class="html-bibr">29</a>].</p>
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<p>Arduino code logic.</p>
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<p>Validation simulation environment in RoboDK, including two industrial robots, two feedback lamps, a virtual display that shows real-time sensor readings, and the project tree, including objects, robot targets, and movement programs and Python scripts.</p>
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<p>Visual feedback on the simulation environment in RoboDK at the state change of the first sensor: text and color feedback on the GUI, color feedback of the left-side lamp, and virtual display feedback.</p>
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<p>Image capturing the start of the movement routine of the orange robot triggered at the state change of the second sensor.</p>
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<p>The hardware and software setup, including sensors and buttons, Arduino board, and a computer running RoboDK and the Python script.</p>
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<p>Validation simulation environment in RoboDK imitating a real-world automated palletizing operation. The robotic arm interacts with a conveyor system and a sensor-based feedback loop, displaying real-time distance and object detection data on a virtual screen.</p>
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<p>Placement of the virtual sensor on the gripper. The sensor is placed under the gripper in order to measure the distance to the box and close the gripper when the box is close enough.</p>
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<p>Station at rest with the robot waiting in its “home” position and the push of the first button (start button) to start the palletizing routine.</p>
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<p>The robot approaches the first box until the distance value becomes smaller than the threshold and triggers the closing action of the clamps.</p>
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<p>Measured distance reaches the threshold and triggers the “box in range” signal. The gripper clamps close and the robot continues its palletizing routine.</p>
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<p>Program halts at the push of the second button (emergency stop). The status lamp becomes red, and the robot stops moving, even if the “box in range” signal is active.</p>
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<p>Logical diagram of the Python script.</p>
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<p>(<b>a</b>) Some Python script functions corresponding to the UI for selecting the operating mode (manual/automatic) and executing RoboDK programs in correspondence with received signal values. (<b>b</b>) Python script function responsible for continuously reading data from Arduino and triggering RoboDK actions based on received signals.</p>
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<p>(<b>a</b>) Some Python script functions corresponding to the UI for selecting the operating mode (manual/automatic) and executing RoboDK programs in correspondence with received signal values. (<b>b</b>) Python script function responsible for continuously reading data from Arduino and triggering RoboDK actions based on received signals.</p>
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<p>Graphical representation of the latency evolution during 60 min of continuous operation.</p>
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<p>Histogram of latency measurements during test period of 60 min.</p>
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31 pages, 5088 KiB  
Review
Advances in Wearable Biosensors for Wound Healing and Infection Monitoring
by Dang-Khoa Vo and Kieu The Loan Trinh
Biosensors 2025, 15(3), 139; https://doi.org/10.3390/bios15030139 - 23 Feb 2025
Viewed by 354
Abstract
Wound healing is a complicated biological process that is important for restoring tissue integrity and function after injury. Infection, usually due to bacterial colonization, significantly complicates this process by hindering the course of healing and enhancing the chances of systemic complications. Recent advances [...] Read more.
Wound healing is a complicated biological process that is important for restoring tissue integrity and function after injury. Infection, usually due to bacterial colonization, significantly complicates this process by hindering the course of healing and enhancing the chances of systemic complications. Recent advances in wearable biosensors have transformed wound care by making real-time monitoring of biomarkers such as pH, temperature, moisture, and infection-related metabolites like trimethylamine and uric acid. This review focuses on recent advances in biosensor technologies designed for wound management. Novel sensor architectures, such as flexible and stretchable electronics, colorimetric patches, and electrochemical platforms, enable the non-invasive detection of changes associated with wounds with high specificity and sensitivity. These are increasingly combined with AI and analytics based on smartphones that can enable timely and personalized interventions. Examples are the PETAL patch sensor that applies multiple sensing mechanisms for wide-ranging views on wound status and closed-loop systems that connect biosensors to therapeutic devices to automate infection control. Additionally, self-powered biosensors that tap into body heat or energy from the biofluids themselves avoid any external batteries and are thus more effective in field use or with limited resources. Internet of Things connectivity allows further support for remote sharing and monitoring of data, thus supporting telemedicine applications. Although wearable biosensors have developed relatively rapidly and their prospects continue to expand, regular clinical application is stalled by significant challenges such as regulatory, cost, patient compliance, and technical problems related to sensor accuracy, biofouling, and power, among others, that need to be addressed by innovative solutions. The goal of this review is to synthesize current trends, challenges, and future directions in wound healing and infection monitoring, with emphasis on the potential for wearable biosensors to improve patient outcomes and reduce healthcare burdens. These innovations are leading the way toward next-generation wound care by bridging advanced materials science, biotechnology, and digital health. Full article
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Graphical abstract

Graphical abstract
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<p>Stages of wound healing. Created with mindthegraph.com.</p>
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<p>Regulators of wound healing and fibrosis. The timing, overlap, and intensity of activation in each phase of wound healing are governed by several molecular, biological, and mechanical variables. The image illustrates how each of these elements influences wound healing. Blue indicates activation, while pink denotes attenuation of fibrosis. Copyright MDPI (2020) [<a href="#B29-biosensors-15-00139" class="html-bibr">29</a>].</p>
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<p>Schematic of the PETAL sensor, a wound healing monitoring sensor working without a battery. (<b>A</b>) A graphical abstract of the sensor adhered onto a burn wound for colorimetric analysis of wound healing progress. (<b>B</b>) The real sensor patch and the multiplexed sensing targets/principles. (<b>C</b>) The shape and dimension of the sensor patch compared to a 50 cent Singapore coin. (<b>D</b>) Schematic of neural network-based machine learning algorithm used for wound classification. Copyright AAAS (2023) [<a href="#B50-biosensors-15-00139" class="html-bibr">50</a>].</p>
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<p>Fabrication and application of flexible carbon ultramicroelectrode arrays (CUAs) in electrochemical detection of multianalyte biomarkers for wound monitoring. Detection of pyocyanin (PYO), uric acid, and nitric oxide (NO•) as biomarkers in simulated wound media. Monitoring pathogen–host interactions and the effects of silver ions (Ag<sup>+</sup>) on PYO secretion by Pseudomonas aeruginosa. Quantification of cellular NO• from immune cells in the wound matrix using flexible CUAs. Copyright ACS Publications (2020) [<a href="#B165-biosensors-15-00139" class="html-bibr">165</a>].</p>
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<p>Bacteria-activated dual pH- and temperature-responsive hydrogel for infection control and wound healing. (<b>a</b>) Schematic of hydrogel cross-linked with <span class="html-italic">N</span>-isopropylacrylamide and acrylic acid, loaded with ultrasmall silver nanoparticles (AgNPs). (<b>b</b>) pH- and temperature-triggered Ag<sup>+</sup> ion release, with restricted release at acidic pH (&lt;5.5) and &gt;90% release at alkaline pH (&gt;7.4). (<b>c</b>) In vivo studies demonstrating clearance of Staphylococcus aureus infection and significantly accelerated wound healing. Copyright ACS Publications (2022) [<a href="#B171-biosensors-15-00139" class="html-bibr">171</a>].</p>
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<p>A bioresorbable pH sensor for wireless monitoring of pH. (<b>A</b>) Illustration for medical application of the proposed sensor in locally monitoring gastric leakage after LSG surgery. (<b>B</b>) Structure of the pH sensor and its compositions. (<b>C</b>) Experimental and simulation results of pH-triggered physical expansion of the sensor after 2 h of immersion in solutions of varying pH. Copyright AAAS (2024) [<a href="#B204-biosensors-15-00139" class="html-bibr">204</a>].</p>
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20 pages, 4568 KiB  
Article
Frame-Stacking Method for Dark Digital Holographic Microscopy to Acquire 3D Profiles in a Low-Power Laser Environment
by Takahiro Koga, Kosei Nakamura, Hyun-Woo Kim, Myungjin Cho and Min-Chul Lee
Electronics 2025, 14(5), 879; https://doi.org/10.3390/electronics14050879 - 23 Feb 2025
Viewed by 159
Abstract
Digital Holographic Microscopy (DHM) is a method of converting hologram images into three-dimensional (3D) images by image processing, which enables us to obtain the detailed shapes of the objects to be observed. Three-dimensional imaging of the microscopic objects by DHM can contribute to [...] Read more.
Digital Holographic Microscopy (DHM) is a method of converting hologram images into three-dimensional (3D) images by image processing, which enables us to obtain the detailed shapes of the objects to be observed. Three-dimensional imaging of the microscopic objects by DHM can contribute to the early diagnosis and the detection of the diseases in the medical field by observing the shape of the cells. DHM requires several experimental components. One of them is the laser, which is a problem because its high power may cause the deformation and the destruction of the cells and the death of the microorganisms. Since the greatest advantage of DHM is the detailed geometrical information of the object by 3D measurement, the loss of such information is a serious problem. To solve this problem, a Neutral Density (ND) filter has been used to reduce power after the laser irradiation. However, the image acquired by the image sensor becomes too dark to obtain sufficient information, and the effect of noise increased due to the decrease in the amount of light. Therefore, in this paper, we propose the Frame-Stacking Method (FSM) for dark DHM for reproducing 3D profiles that enable us to observe the shape of the objects from the images taken in low-power environments when the power is reduced. The proposed method realizes highly accurate 3D profiles by the frame decomposition of the low-power videos into images and superimposing and rescaling the obtained low-power images. On the other hand, the continuous irradiation of the laser beam for a long period may destroy the shape of the cells and the death of the microorganisms. Therefore, we conducted experiments to investigate the relationship between the number of superimposed images corresponding to the irradiation time and the 3D profile, as well as the characteristics of the power and the 3D profile. Full article
(This article belongs to the Special Issue Computational Imaging and Its Application)
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<p>Digital Holography overline.</p>
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<p>Interferometer and hologram image.</p>
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<p>The scheme of wavefront distortion by a transparent phase object with high refractive index.</p>
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<p>Image processing of DHM using the Fourier transform method. Red square: region of interest.</p>
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<p>Difference between the actual object and the object in the 3D profile.</p>
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<p>The ideal shape of the microsphere using MATLAB R2024a. (<b>a</b>) 3D profile; (<b>b</b>) cross-sectional height profile along the x-axis.</p>
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<p>Hologram images by (<b>a</b>) normal power and (<b>b</b>) low-power laser.</p>
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<p>Relationship between luminance values in low-power laser environments.</p>
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<p>Histogram of numerical data for (<b>a</b>) normal laser and (<b>b</b>) low-power laser environments.</p>
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<p>Three-dimensional profiles of hologram and cross-sectional height profiles along the x-axis (<b>a</b>) before passing through the ND filter and (<b>b</b>) after passing through the ND filter.</p>
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<p>A system flowchart of the 3D process in DHM of (<b>a</b>) the conventional and (<b>b</b>) the proposed methods.</p>
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<p>The experimental setup of the Mach–Zehnder interferometer.</p>
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<p>The 3D profile results and cross-sectional height profile along the x-axis of (<b>a</b>) the conventional and (<b>b</b>) the proposed methods.</p>
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<p>A comparison of the to-be-evaluated and ideal shapes.</p>
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<p>Three-dimensional profiles and cross-sectional height profiles along the x-axis in the number of the superimposed images. (<b>a</b>) 1 frame; (<b>b</b>) 50 frames; (<b>c</b>) 100 frames; (<b>d</b>) 500 frames; (<b>e</b>) 3000 frames; and (<b>f</b>) 5000 frames.</p>
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<p>Three-dimensional profile evaluation by SSIM on the number of the superimposed images.</p>
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<p>The 3D profiles and cross-sectional height profile along the x-axis of each power value of the laser. (<b>a</b>) 0.010 mW; (<b>b</b>) 0.015 mW; (<b>c</b>) 0.020 mW; (<b>d</b>) 0.025 mW; and (<b>e</b>) 0.030 mW.</p>
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<p>Three-dimensional profile evaluation for each power value of the laser by SSIM.</p>
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<p>Three-dimensional profiles and cross-sectional height profile along the x-axis of the optimal power and the number of superimposed images by (<b>a</b>) the conventional and (<b>b</b>) the proposed methods.</p>
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<p>Hologram image, 3D profile, and cross-sectional height profile along the x-axis of RBCs taken in the normal power environment.</p>
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<p>Three-dimensional profile results of RBCs. (<b>a</b>) The conventional and (<b>b</b>) the proposed methods.</p>
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50 pages, 5449 KiB  
Review
Artificial Intelligence and Internet of Things Integration in Pharmaceutical Manufacturing: A Smart Synergy
by Reshma Kodumuru, Soumavo Sarkar, Varun Parepally and Jignesh Chandarana
Pharmaceutics 2025, 17(3), 290; https://doi.org/10.3390/pharmaceutics17030290 - 22 Feb 2025
Viewed by 1373
Abstract
Background: The integration of artificial intelligence (AI) with the internet of things (IoTs) represents a significant advancement in pharmaceutical manufacturing and effectively bridges the gap between digital and physical worlds. With AI algorithms integrated into IoTs sensors, there is an improvement in the [...] Read more.
Background: The integration of artificial intelligence (AI) with the internet of things (IoTs) represents a significant advancement in pharmaceutical manufacturing and effectively bridges the gap between digital and physical worlds. With AI algorithms integrated into IoTs sensors, there is an improvement in the production process and quality control for better overall efficiency. This integration facilitates enabling machine learning and deep learning for real-time analysis, predictive maintenance, and automation—continuously monitoring key manufacturing parameters. Objective: This paper reviews the current applications and potential impacts of integrating AI and the IoTs in concert with key enabling technologies like cloud computing and data analytics, within the pharmaceutical sector. Results: Applications discussed herein focus on industrial predictive analytics and quality, underpinned by case studies showing improvements in product quality and reductions in downtime. Yet, many challenges remain, including data integration and the ethical implications of AI-driven decisions, and most of all, regulatory compliance. This review also discusses recent trends, such as AI in drug discovery and blockchain for data traceability, with the intent to outline the future of autonomous pharmaceutical manufacturing. Conclusions: In the end, this review points to basic frameworks and applications that illustrate ways to overcome existing barriers to production with increased efficiency, personalization, and sustainability. Full article
(This article belongs to the Section Pharmaceutical Technology, Manufacturing and Devices)
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<p>The architecture of the IoTs.</p>
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<p>Application of artificial intelligence in enhancing the drug development and distribution life cycle.</p>
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<p>Application of AI tools in the pharmaceutical sector.</p>
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<p>Research methodology.</p>
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<p>AI and IoTs technologies applications.</p>
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<p>Different AI learning models/tools for predictive pharmaceutical maintenance solutions. For example <a href="https://www.tensorflow.org/" target="_blank">https://www.tensorflow.org/</a>, accessed on 21 February 2025; <a href="https://elevenlabs.io/developers" target="_blank">https://elevenlabs.io/developers</a>, accessed on 21 February 2025; <a href="https://pytorch.org/" target="_blank">https://pytorch.org/</a>, accessed on 21 February 2025.</p>
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<p>AI contribution to the development of drugs and rise in the precision of selection of parameters and factors in drug design, drug discovery, and drug repurposing methods. It also helps to understand better the mechanism of membrane interaction with the modeled human environment by studying drug permeation, simulation, and human cell targets.</p>
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<p>Challenges and limitations of IoTs and AI in pharmaceutical manufacturing.</p>
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<p>Quality control technologies in pharmaceutical manufacturing.</p>
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15 pages, 2878 KiB  
Article
Preparation of Ion Composite Photosensitive Resin and Its Application in 3D-Printing Highly Sensitive Pressure Sensor
by Tong Guan, Huayang Li, Jinyun Liu, Wuxu Zhang, Siying Wang, Wentao Ye, Baoru Bian, Xiaohui Yi, Yuanzhao Wu, Yiwei Liu, Juan Du, Jie Shang and Run-Wei Li
Sensors 2025, 25(5), 1348; https://doi.org/10.3390/s25051348 - 22 Feb 2025
Viewed by 244
Abstract
Flexible pressure sensors play an extremely important role in the fields of intelligent medical treatment, humanoid robots, and so on. However, the low sensitivity and the small initial capacitance still limit its application and development. At present, the method of constructing the microstructure [...] Read more.
Flexible pressure sensors play an extremely important role in the fields of intelligent medical treatment, humanoid robots, and so on. However, the low sensitivity and the small initial capacitance still limit its application and development. At present, the method of constructing the microstructure of the dielectric layer is commonly used to improve the sensitivity of the sensor, but there are some problems, such as the complex process and inaccurate control of the microstructure. In this work, an ion composite photosensitive resin based on polyurethane acrylate and ionic liquids (ILs) was prepared. The high compatibility of the photosensitive resin and ILs was achieved by adding a chitooligosaccharide (COS) chain extender. The microstructure of the dielectric layer was optimized by digital light processing (DLP) 3D-printing. Due to the introduction of ILs to construct an electric double layer (EDL), the flexible pressure sensor exhibits a high sensitivity of 32.62 kPa−1, which is 12.2 times higher than that without ILs. It also has a wide range of 100 kPa and a fast response time of 51 ms. It has a good pressure response under different pressures and can realize the demonstration application of human health. Full article
(This article belongs to the Special Issue Wearable Sensors for Continuous Health Monitoring and Analysis)
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<p>Curing principle of ion composite photosensitive resin: (<b>a</b>) chemical structure of PUA, COS, PEG(600)DMA, and [EMIM][TFSI]; and (<b>b</b>) the schematic diagram of UV curing and heat curing.</p>
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<p>(<b>a</b>) Preparation process of dielectric layer; (<b>b</b>,<b>c</b>) SEM and EDX on the surface of ion composite photosensitive resin without COS; (<b>d</b>,<b>e</b>) the cross-section SEM and EDX of ion composite photosensitive resin without COS; (<b>f</b>,<b>g</b>) SEM and EDX on the surface of ion composite photosensitive resin with COS; (<b>h</b>,<b>i</b>) the cross section SEM and EDX of ion composite photosensitive resin with COS; and (<b>j</b>) image of different structures by DLP 3D printing.</p>
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<p>Mechanical and electrical properties of ion composite photosensitive resin: (<b>a</b>–<b>c</b>) the mechanical properties changed with the content of COS, PEG(600)DMA, and ILs; (<b>d</b>) the comparison of the tensile loading–unloading curves of the ion composite photosensitive resin containing 40 wt.% ILs (PUA@ILs) and other commercial flexible photosensitive resins; and (<b>e</b>,<b>f</b>) distribution of sample conductivity before and after compression.</p>
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<p>3D printing of ion composite photosensitive resin: (<b>a</b>) relationship between viscosity of photosensitive resin and content of [EMIM][TFSI]; (<b>b</b>) the relationship between curing depth and exposure energy; (<b>c</b>) horizontal resolution of ion composite photosensitive resin; and (<b>d</b>) image of TYPE-C structure printed by ion composite photosensitive resin.</p>
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<p>Sensing performance of the 3D-printed capacitive sensor based on ion composite photosensitive resin: (<b>a</b>) sensor structure diagram; (<b>b</b>) the ΔC/C<sub>0</sub>–P relation of sensors with dielectric layers of different lattice structures; (<b>c</b>) the ΔC/C<sub>0</sub>–P relation of sensors with TYPE-C dielectric layers of different density ratios; (<b>d</b>) the ΔC/C<sub>0</sub>–P relation of TYPE-C structure with 25% density ratio; (<b>e</b>) the sensitivity of sensors with different dielectric layer materials; and (<b>f</b>) comparison of sensitivity and range (sensitivity &gt; 0.1 kPa<sup>−1</sup>) of different capacitive sensors based on photosensitive resin [<a href="#B32-sensors-25-01348" class="html-bibr">32</a>,<a href="#B37-sensors-25-01348" class="html-bibr">37</a>,<a href="#B38-sensors-25-01348" class="html-bibr">38</a>,<a href="#B39-sensors-25-01348" class="html-bibr">39</a>,<a href="#B47-sensors-25-01348" class="html-bibr">47</a>,<a href="#B48-sensors-25-01348" class="html-bibr">48</a>].</p>
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<p>Other sensing performance and application demonstrations of the 3D-printed capacitive sensor based on ion composite photosensitive resin: (<b>a</b>) response time of the sensor at approximately 3 kPa; (<b>b</b>) response of the sensor to a gradually increasing force of 20 kPa; (<b>c</b>) the cyclic response of the sensor under different pressures (1 kPa, 10 kPa, 20 kPa, 50 kPa, and 100 kPa); (<b>d</b>) response of the sensor under 1000 cycles; (<b>e</b>) real-time monitoring of human pulse; and (<b>f</b>) real-time monitoring of deep breath, swallow, and cough in the human throat.</p>
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20 pages, 5052 KiB  
Article
Assessment of the Mechanical Properties of Soft Tissue Phantoms Using Impact Analysis
by Arthur Bouffandeau, Anne-Sophie Poudrel, Chloé Brossier, Giuseppe Rosi, Vu-Hieu Nguyen, Charles-Henri Flouzat-Lachaniette, Jean-Paul Meningaud and Guillaume Haïat
Sensors 2025, 25(5), 1344; https://doi.org/10.3390/s25051344 - 22 Feb 2025
Viewed by 104
Abstract
Skin physiopathological conditions have a strong influence on its biomechanical properties. However, it remains difficult to accurately assess the surface stiffness of soft tissues. The aim of this study was to evaluate the performances of an impact-based analysis method (IBAM) and to compare [...] Read more.
Skin physiopathological conditions have a strong influence on its biomechanical properties. However, it remains difficult to accurately assess the surface stiffness of soft tissues. The aim of this study was to evaluate the performances of an impact-based analysis method (IBAM) and to compare them with those of an existing digital palpation device, MyotonPro®. The IBAM is based on the impact of an instrumented hammer equipped with a force sensor on a cylindrical punch in contact with agar-based phantoms mimicking soft tissues. The indicator Δt is estimated by analyzing the force signal obtained from the instrumented hammer. Various phantom geometries, stiffnesses and structures (homogeneous and bilayer) were used to estimate the performances of both methods. Measurements show that the IBAM is sensitive to a volume of interest equivalent to a sphere approximately twice the punch diameter. The sensitivity of the IBAM to changes in Young’s modulus is similar to that of dynamic mechanical analysis (DMA) and significantly better compared to MyotonPro. The axial (respectively, lateral) resolution is two (respectively, five) times lower with the IBAM than with MyotonPro. The present study paves the way for the development of a simple, quantitative and non-invasive method to measure skin biomechanical properties. Full article
(This article belongs to the Special Issue (Bio)sensors for Physiological Monitoring)
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<p>Experimental set-up of the impact-based analysis method (IBAM). During a measurement, the instrumented hammer impacts the punch, which is vertically guided. The lower part of the punch is in contact with the agar-based phantom held by the support.</p>
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<p>Example of a signal recorded by the force sensor impacting the hammer (impact <span class="html-italic">#i</span>) with a 3% agar-based phantom mimicking soft tissues. The temporal indicator <math display="inline"><semantics> <mrow> <mi mathvariant="sans-serif">Δ</mi> <msub> <mi>t</mi> <mi>i</mi> </msub> </mrow> </semantics></math>, where <math display="inline"><semantics> <mrow> <msub> <mi>t</mi> <mrow> <mi>i</mi> <mo>,</mo> <mn>1</mn> </mrow> </msub> </mrow> </semantics></math> is the time of impact hammer and <math display="inline"><semantics> <mrow> <msub> <mi>t</mi> <mrow> <mi>i</mi> <mo>,</mo> <mn>2</mn> </mrow> </msub> </mrow> </semantics></math> is the time of the first rebound of the punch on the hammer, and the impact force <math display="inline"><semantics> <mrow> <mi>I</mi> <mi>F</mi> </mrow> </semantics></math> are indicated. Here, <math display="inline"><semantics> <mrow> <mi mathvariant="sans-serif">Δ</mi> <msub> <mi>t</mi> <mi>i</mi> </msub> </mrow> </semantics></math> = 1.61 ms and <math display="inline"><semantics> <mrow> <mi>I</mi> <mi>F</mi> </mrow> </semantics></math> = 32.5 N.</p>
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<p>Experimental set-up using MyotonPro device to characterize a 3% agar-based phantom mimicking soft tissues.</p>
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<p>Schematic illustration of the custom vibration-based set-up performed on agar-based phantoms mimicking soft tissues to determine their Young’s moduli.</p>
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<p>Illustration of the two experimental protocols for the estimation of the spatial resolution for the IBAM and MyotonPro. (<b>a</b>) Evaluation of the axial resolution for the two conditions “rigid on soft” and “soft on rigid” where the top layer thicknesses <math display="inline"><semantics> <mrow> <msub> <mi>h</mi> <mrow> <mn>5</mn> <mo>%</mo> </mrow> </msub> </mrow> </semantics></math> and <math display="inline"><semantics> <mrow> <msub> <mi>h</mi> <mrow> <mn>2</mn> <mo>%</mo> </mrow> </msub> </mrow> </semantics></math> (in bold on the figure) vary between 40 mm and 0 mm; (<b>b</b>) evaluation of the lateral resolution.</p>
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<p>Variation in the indicators <math display="inline"><semantics> <mrow> <mi mathvariant="sans-serif">Δ</mi> <mi>t</mi> </mrow> </semantics></math> and <math display="inline"><semantics> <mi>S</mi> </semantics></math> obtained with the IBAM and MyotonPro as a function of the sample diameter with a 3% agar mass concentration. The error bars correspond to the reproducibility of the measurements.</p>
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<p>Variation in the indicators <math display="inline"><semantics> <mrow> <mi mathvariant="sans-serif">Δ</mi> <mi>t</mi> </mrow> </semantics></math> and <math display="inline"><semantics> <mi>S</mi> </semantics></math> obtained with the IBAM and MyotonPro as a function of the sample length with a 3% agar mass concentration. The error bars correspond to the reproducibility of the measurements.</p>
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<p>Variation in the indicators <math display="inline"><semantics> <mrow> <mi mathvariant="sans-serif">Δ</mi> <mi>t</mi> </mrow> </semantics></math> and <math display="inline"><semantics> <mi>S</mi> </semantics></math> obtained with the IBAM and MyotonPro as a function of the top layer thickness <math display="inline"><semantics> <mrow> <msub> <mi>h</mi> <mrow> <mn>5</mn> <mo>%</mo> </mrow> </msub> </mrow> </semantics></math> for the “rigid on soft” configuration. The error bars correspond to the reproducibility of the measurements.</p>
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<p>Variation in the indicators <math display="inline"><semantics> <mrow> <mi mathvariant="sans-serif">Δ</mi> <mi>t</mi> </mrow> </semantics></math> and <math display="inline"><semantics> <mi>S</mi> </semantics></math> obtained with the IBAM and MyotonPro as a function of the top layer thickness <math display="inline"><semantics> <mrow> <msub> <mi>h</mi> <mrow> <mn>2</mn> <mo>%</mo> </mrow> </msub> </mrow> </semantics></math> for the “soft on rigid” configuration. The error bars correspond to the reproducibility of the measurements.</p>
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<p>Variation in the indicators <math display="inline"><semantics> <mrow> <mi mathvariant="sans-serif">Δ</mi> <mi>t</mi> </mrow> </semantics></math> and <math display="inline"><semantics> <mi>S</mi> </semantics></math> obtained with the IBAM and MyotonPro as a function of the measurement position <math display="inline"><semantics> <mi>x</mi> </semantics></math> on the upper surface of the bilayer samples. The error bars correspond to the reproducibility of the measurements. The color corresponds to the color indicated in <a href="#sensors-25-01344-f005" class="html-fig">Figure 5</a>b.</p>
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<p>Variation in the indicators <math display="inline"><semantics> <mrow> <mi mathvariant="sans-serif">Δ</mi> <mi>t</mi> </mrow> </semantics></math> and <math display="inline"><semantics> <mi>S</mi> </semantics></math> obtained with the IBAM and MyotonPro as a function of the Young’s modulus <math display="inline"><semantics> <mi>E</mi> </semantics></math> of soft tissue phantoms obtained for agar mass concentrations varying between 1 and 5% using custom vibration-based set-up. The error bars correspond to the reproducibility of the measurements. The dashed line is the curve fitting with a power function of <math display="inline"><semantics> <mrow> <mi mathvariant="sans-serif">Δ</mi> <mi>t</mi> </mrow> </semantics></math> as a function of <math display="inline"><semantics> <mi>E</mi> </semantics></math>.</p>
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<p>Comparison of the variation in the Young’s modulus of soft tissue phantoms <math display="inline"><semantics> <mi>E</mi> </semantics></math> as a function of the agar mass concentrations using various measurement methods [<a href="#B26-sensors-25-01344" class="html-bibr">26</a>,<a href="#B42-sensors-25-01344" class="html-bibr">42</a>,<a href="#B43-sensors-25-01344" class="html-bibr">43</a>,<a href="#B44-sensors-25-01344" class="html-bibr">44</a>]. The error bars correspond to the reproducibility of the measurements.</p>
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30 pages, 3836 KiB  
Article
Optimizing Facilities Management Through Artificial Intelligence and Digital Twin Technology in Mega-Facilities
by Ahmed Mohammed Abdelalim, Ahmed Essawy, Alaa Sherif, Mohamed Salem, Manal Al-Adwani and Mohammad Sadeq Abdullah
Sustainability 2025, 17(5), 1826; https://doi.org/10.3390/su17051826 - 21 Feb 2025
Viewed by 322
Abstract
Mega-facility management has long been inefficient due to manual, reactive approaches. Current facility management systems face challenges such as fragmented data integration, limited predictive systems, use of traditional methods, and lack of knowledge of new technologies, such as Building Information Modeling and Artificial [...] Read more.
Mega-facility management has long been inefficient due to manual, reactive approaches. Current facility management systems face challenges such as fragmented data integration, limited predictive systems, use of traditional methods, and lack of knowledge of new technologies, such as Building Information Modeling and Artificial Intelligence. This study examines the transformative integration of Artificial Intelligence and Digital Twin technologies into Building Information Modeling (BIM) frameworks using IoT sensors for real-time data collection and predictive analytics. Unlike previous research, this study uses case studies and simulation models for dynamic data integration and scenario-based analyses. Key findings show a significant reduction in maintenance costs (25%) and energy consumption (20%), as well as increased asset utilization and operational efficiency. With an F1-score of more than 90%, the system shows excellent predictive accuracy for equipment failures and energy forecasting. Practical applications in hospitals and airports demonstrate the developed ability of the platform to integrate the Internet of Things and Building Information Modeling technologies, shifting facilities management from being reactive to proactive. This paper presents a demo platform that integrates BIM with Digital Twins to improve the predictive maintenance of HVAC systems, equipment, security systems, etc., by recording data from different assets, which helps streamline asset management, enhance energy efficiency, and support decision-making for the buildings’ critical systems. Full article
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<p>Flowchart for implementing AI-BIM-IoT in an existing building.</p>
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<p>Implementing a Digital Twin for any building.</p>
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<p>User registration.</p>
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<p>User interface of the platform.</p>
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<p>Uploading the IFC file to the platform.</p>
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<p>Specifying the geographical location of the building.</p>
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<p>Geometry of the building in 3D view.</p>
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<p>Real-time sensor data.</p>
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<p>Alarm message.</p>
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<p>Applying AI scenarios.</p>
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<p>Program mapping for all sensors.</p>
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<p>Framework for DT platform.</p>
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49 pages, 3741 KiB  
Review
Optimal Sensor Placement for Structural Health Monitoring: A Comprehensive Review
by Zhiyan Sun, Mojtaba Mahmoodian, Amir Sidiq, Sanduni Jayasinghe, Farham Shahrivar and Sujeeva Setunge
J. Sens. Actuator Netw. 2025, 14(2), 22; https://doi.org/10.3390/jsan14020022 - 20 Feb 2025
Viewed by 274
Abstract
The structural health monitoring (SHM) of bridge infrastructure has become essential for ensuring safety, serviceability, and long-term functionality amid aging structures and increasing load demands. SHM leverages sensor networks to enable real-time data acquisition, damage detection, and predictive maintenance, offering a more reliable [...] Read more.
The structural health monitoring (SHM) of bridge infrastructure has become essential for ensuring safety, serviceability, and long-term functionality amid aging structures and increasing load demands. SHM leverages sensor networks to enable real-time data acquisition, damage detection, and predictive maintenance, offering a more reliable alternative to traditional visual inspection methods. A key challenge in SHM is optimal sensor placement (OSP), which directly impacts monitoring accuracy, cost-efficiency, and overall system performance. This review explores recent advancements in SHM techniques, sensor technologies, and OSP methodologies, with a primary focus on bridge infrastructure. It evaluates sensor configuration strategies based on criteria such as the modal assurance criterion (MAC) and mean square error (MSE) while examining optimisation approaches like the Effective Independence (EI) method, Kinetic Energy Optimisation (KEO), and their advanced variants. Despite these advancements, several research gaps remain. Future studies should focus on scalable OSP strategies for large-scale bridge networks, integrating machine learning (ML) and artificial intelligence (AI) for adaptive sensor deployment. The implementation of digital twin (DT) technology in SHM can enhance predictive maintenance and real-time decision-making, improving long-term infrastructure resilience. Additionally, research on sensor robustness against environmental noise and external disturbances, as well as the integration of edge computing and wireless sensor networks (WSNs) for efficient data transmission, will be critical in advancing SHM applications. This review provides critical insights and recommendations to bridge the gap between theoretical innovations and real-world implementation, ensuring the effective monitoring and maintenance of bridge infrastructure in modern civil engineering. Full article
(This article belongs to the Section Actuators, Sensors and Devices)
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<p>Distribution of railway bridge aging status in Australia (Reprint from Ref. [<a href="#B13-jsan-14-00022" class="html-bibr">13</a>]).</p>
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<p>Literature review methodology.</p>
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<p>Schematic flow chart of the structure of the study.</p>
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<p>Overview of current maintenance processes (reprint from Ref. [<a href="#B33-jsan-14-00022" class="html-bibr">33</a>]).</p>
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<p>SHM approach to infrastructure assessment and decision-making.</p>
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<p>Schematic of the GNSS (global navigation satellite system) wireless sensor node.</p>
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<p>Abnormal detection by the proposed method based on VME and novelty detection.</p>
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<p>Impacts of employing diverse approaches to sensor placement.</p>
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<p>System linear dependence measurement variations (<b>a</b>) Sufficient Measurement, (<b>b</b>) Insufficient Measurement.</p>
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<p>Typical OSP workflow.</p>
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<p>Pseudocode of the Firefly Algorithm (Reprint from Ref. [<a href="#B154-jsan-14-00022" class="html-bibr">154</a>]).</p>
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<p>MAC applied in existing OSP studies.</p>
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20 pages, 1619 KiB  
Systematic Review
A Breakthrough in Producing Personalized Solutions for Rehabilitation and Physiotherapy Thanks to the Introduction of AI to Additive Manufacturing
by Emilia Mikołajewska, Dariusz Mikołajewski, Tadeusz Mikołajczyk and Tomasz Paczkowski
Appl. Sci. 2025, 15(4), 2219; https://doi.org/10.3390/app15042219 - 19 Feb 2025
Viewed by 348
Abstract
The integration of artificial intelligence (AI) with additive manufacturing (AM) is driving breakthroughs in personalized rehabilitation and physical therapy solutions, enabling precise customization to individual patient needs. This article presents the current state of knowledge and perspectives of using personalized solutions for rehabilitation [...] Read more.
The integration of artificial intelligence (AI) with additive manufacturing (AM) is driving breakthroughs in personalized rehabilitation and physical therapy solutions, enabling precise customization to individual patient needs. This article presents the current state of knowledge and perspectives of using personalized solutions for rehabilitation and physiotherapy thanks to the introduction of AI to AM. Advanced AI algorithms analyze patient-specific data such as body scans, movement patterns, and medical history to design customized assistive devices, orthoses, and prosthetics. This synergy enables the rapid prototyping and production of highly optimized solutions, improving comfort, functionality, and therapeutic outcomes. Machine learning (ML) models further streamline the process by anticipating biomechanical needs and adapting designs based on feedback, providing iterative refinement. Cutting-edge techniques leverage generative design and topology optimization to create lightweight yet durable structures that are ideally suited to the patient’s anatomy and rehabilitation goals .AI-based AM also facilitates the production of multi-material devices that combine flexibility, strength, and sensory capabilities, enabling improved monitoring and support during physical therapy. New perspectives include integrating smart sensors with printed devices, enabling real-time data collection and feedback loops for adaptive therapy. Additionally, these solutions are becoming increasingly accessible as AM technology lowers costs and improves, democratizing personalized healthcare. Future advances could lead to the widespread use of digital twins for the real-time simulation and customization of rehabilitation devices before production. AI-based virtual reality (VR) and augmented reality (AR) tools are also expected to combine with AM to provide immersive, patient-specific training environments along with physical aids. Collaborative platforms based on federated learning can enable healthcare providers and researchers to securely share AI insights, accelerating innovation. However, challenges such as regulatory approval, data security, and ensuring equity in access to these technologies must be addressed to fully realize their potential. One of the major gaps is the lack of large, diverse datasets to train AI models, which limits their ability to design solutions that span different demographics and conditions. Integration of AI–AM systems into personalized rehabilitation and physical therapy should focus on improving data collection and processing techniques. Full article
(This article belongs to the Special Issue Additive Manufacturing in Material Processing)
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<p>PRISMA flow diagram of the review process.</p>
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<p>Basic results of the review: (<b>a</b>) by year, (<b>b</b>) by discipline.</p>
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<p>The most common current use of AI-supported AM in rehabilitation and physiotherapy (authors’ own elaboration).</p>
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<p>Possible future customization of AI–supported 3D printed assistive technologies in rehabilitation and physiotherapy (authors’ own elaboration).</p>
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18 pages, 6572 KiB  
Article
Development of a Digital System for Monitoring Emergency Conditions in 20 kV Distribution Networks
by Alisher Baltin, Sultanbek Issenov, Gulim Nurmaganbetova, Aliya Zhumadirova, Assel Yussupova, Alexandra Potapenko and Aliya Maussymbayeva
Energies 2025, 18(4), 998; https://doi.org/10.3390/en18040998 - 19 Feb 2025
Viewed by 229
Abstract
This article presents research on the possibilities of using information and communication technologies in monitoring systems for electrical networks with isolated neutral, aimed at improving and automating production functions in the energy sector. This aligns with the digitalization policy of Kazakhstan’s economy and [...] Read more.
This article presents research on the possibilities of using information and communication technologies in monitoring systems for electrical networks with isolated neutral, aimed at improving and automating production functions in the energy sector. This aligns with the digitalization policy of Kazakhstan’s economy and is part of similar programs in the field of the electric power industry. This article explores an approach to organizing a digital monitoring system for emergency conditions, specifically single-phase ground faults in medium-voltage lines within the range of 6–35 kV, including the new voltage class of 20 kV. A version of such a system is proposed, based on a combination of a server, a wireless information network, and remote digital voltage measurement nodes. This wireless information and communication network is designed to detect the locations of single-phase ground faults (SPGF) using specialized zero-sequence voltage sensors installed at various points along the power transmission lines, along with wireless signal transmission channels to the dispatcher’s server. To ensure protection against industrial interference, based on the results of practical environment modeling, a transmission technology most resistant to external noise is selected. This article proposes the selection of equipment necessary for implementing wireless transmission technology and develops two versions of a digital voltmeter design based on low-power programmable microcontrollers. The proposed technical solutions require further experimental validation, and therefore, the authors plan to conduct additional research and practical experiments in the future. Full article
(This article belongs to the Section A1: Smart Grids and Microgrids)
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<p>External view of TZRL measuring transformers of different sizes (Description of the transformer type designations: T—current transformer; Z—for ground fault protection; R—split-core (or separable); L—with cast insulation).</p>
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<p>Circuit diagram for connecting windings of three conventional measuring voltage transformers in the 3U<sub>0</sub> measurement mode of phase “a”, phase “b” and phase “c”.</p>
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<p>Converting complex numbers to amplitude-phase format.</p>
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<p>Converting complex numbers to amplitude-phase format that works only with real numbers.</p>
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<p>Converting complex numbers to a combination of real and imaginary parts [<a href="#B8-energies-18-00998" class="html-bibr">8</a>,<a href="#B9-energies-18-00998" class="html-bibr">9</a>].</p>
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<p>Block diagram of the device for generating a signal and error oscillogram.</p>
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<p>Block diagram of the transmission channel model.</p>
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<p>Structural diagram of the transmission system model.</p>
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<p>Model of a Wireless Transmission Channel with FSK Modulation Under Intense Noise Impact.</p>
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<p>Simulation Results of a Channel with FSK Modulation. T1—Original signal, T2—Carrier frequency with FM modulation, T3—Original signal delayed by the signal propagation time in the wireless channel, R—Signal at the output of the receiving path, error—error signal (distortions) representing the difference between the transmitted and received signals. In <a href="#energies-18-00998-f010" class="html-fig">Figure 10</a>, the results of simulating transmission modes in a channel with FSK modulation are presented for two cases: operational (<b>A</b>) and nonoperational (<b>B</b>).</p>
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<p>Example of a signal scatter plot for PSK modulation (BPSK—binary PSK) of operational (<b>A</b>) and nonoperational (<b>B</b>) types.</p>
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<p>Example of a signal scatter plot for PAM modulation of operational (<b>A</b>) and nonoperational (<b>B</b>) types.</p>
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<p>Example of a signal scatter plot for 16-QAM modulation of operational (<b>A</b>) and nonoperational (<b>B</b>) types.</p>
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<p>Simulation results of the LoRa-modulated channel without errors (<b>A</b>) and the transmission channel becomes inoperable (<b>B</b>).</p>
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<p>Structure of the LoRaWAN wireless information technology network.</p>
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<p>Diagram of the use of the base station in the data transmission network.</p>
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<p>Structural diagram of induced voltage measurements.</p>
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<p>Block diagram of the zero-sequence emergency voltage detection node for a 20 kV cable line.</p>
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<p>Block diagram of the remote zero-sequence voltage measurement node for a 20 kV cable line.</p>
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<p>Structure of the primary segment with Internet access [<a href="#B11-energies-18-00998" class="html-bibr">11</a>].</p>
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41 pages, 4616 KiB  
Review
Use of Lighting Technology in Controlled and Semi-Controlled Agriculture in Greenhouses and Protected Agriculture Systems—Part 1: Scientific and Bibliometric Analysis
by Edwin Villagran, John Javier Espitia, Jader Rodriguez, Linda Gomez, Gina Amado, Esteban Baeza, Cruz Ernesto Aguilar-Rodríguez, Jorge Flores-Velazquez, Mohammad Akrami, Rodrigo Gil and Luis Alejandro Arias
Sustainability 2025, 17(4), 1712; https://doi.org/10.3390/su17041712 - 18 Feb 2025
Viewed by 297
Abstract
This paper examines the essential role of artificial lighting in protected agriculture, a crucial sector in addressing the increasing global food demand and the challenges posed by climate change. It explores how advanced lighting technologies, particularly LED systems, have revolutionized productivity and sustainability [...] Read more.
This paper examines the essential role of artificial lighting in protected agriculture, a crucial sector in addressing the increasing global food demand and the challenges posed by climate change. It explores how advanced lighting technologies, particularly LED systems, have revolutionized productivity and sustainability in greenhouses and indoor or urban farming systems. These technologies enable precise control over key factors influencing crop growth, optimizing both yield and resource efficiency. The methodology was based on a bibliometric analysis developed in four phases: collection of information in the scientific database Scopus, filtering and selection of relevant documents, quantitative and qualitative analysis of trends, and visualization of the results using tools such as VOSviewer. The study included scientific publications between 1974 and 2024, focusing on keywords related to greenhouse lighting technologies and protected agriculture systems. Key findings identified a significant increase in research over the last two decades, with countries such as the United States, Canada, the Netherlands, and China leading the way in scientific output. The main trends in artificial lighting for protected agriculture include the use of specific light spectra (particularly red and blue) to optimize photosynthesis and morphogenesis, as well as the integration of LED systems with digital sensors and controllers for enhanced precision. However, in developing countries such as Colombia, the adoption of these technologies remains in its early stages, presenting significant opportunities for implementation and expansion. Additionally, this bibliometric analysis provides a robust foundation for identifying key areas for improvement and guiding future research toward more sustainable and efficient agricultural practices. Full article
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<p>Flow diagram of the systematic review methodology.</p>
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<p>Scientific production by year.</p>
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<p>Document production by subject area.</p>
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<p>Scientific production by country.</p>
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<p>Co-authorship network by country.</p>
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<p>Academic production of the main authors by year.</p>
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<p>Citation network between authors.</p>
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<p>Wordcloud of keywords.</p>
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<p>Citation network between publication sources.</p>
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<p>Keyword co-occurrence network.</p>
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<p>Thematic map of the analyzed area of knowledge.</p>
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<p>Multiple correspondence analysis of the area of knowledge analyzed.</p>
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