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Search Results (674)

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Keywords = second-life applications

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19 pages, 2321 KiB  
Article
Impact of Fibers on the Mechanical and Environmental Properties of High-Performance Concrete Incorporating Zeolite
by Hadi Bahmani and Hasan Mostafaei
J. Compos. Sci. 2025, 9(5), 222; https://doi.org/10.3390/jcs9050222 - 30 Apr 2025
Viewed by 194
Abstract
This study investigates, for the first time, the effects of polypropylene, steel, glass, and synthetic fibers on the mechanical and environmental properties of high-performance concrete (HPC) incorporating zeolite as a substitute for aggregates and cement. A series of tests, including compressive strength (load-displacement), [...] Read more.
This study investigates, for the first time, the effects of polypropylene, steel, glass, and synthetic fibers on the mechanical and environmental properties of high-performance concrete (HPC) incorporating zeolite as a substitute for aggregates and cement. A series of tests, including compressive strength (load-displacement), slump, specific gravity, and water absorption percentage, were conducted to evaluate the performance of the composite materials. Additionally, the IMPACT2002+ method was employed to assess the environmental impacts of the different fiber types. Furthermore, a life cycle costing (LCC) analysis was performed to evaluate the economic feasibility of using these fibers in sustainable HPC applications. The findings reveal that the incorporation of steel fibers results in a notable improvement in compressive strength, achieving 92 MPa compared to 85 MPa for fiber-free samples. Additionally, modified synthetic macro fibers exhibited the second-highest compressive strength, at 83 MPa, while also demonstrating the lowest environmental impact among the tested fibers, characterized by the lowest cost index and minimal carbon dioxide emissions. Full article
(This article belongs to the Special Issue Novel Cement and Concrete Materials)
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17 pages, 1595 KiB  
Article
Enhancing the Survival of Ichneumonid Parasitoid Campoletis chlorideae (Hymenoptera: Ichneumonidae) by Utilizing Haserpin-e Protein to Effectively Manage Lepidopteran Pests
by Liuming Huo, Xue Yao, Ningbo Zhang, Shengyi Wang, Sufen Bai, Yanmei Wang, Jizhen Wei and Shiheng An
Insects 2025, 16(5), 474; https://doi.org/10.3390/insects16050474 - 29 Apr 2025
Viewed by 130
Abstract
The ichneumonid parasitoid Campoletis chlorideae is an important natural enemy of lepidopteran pests in different agro-ecosystems, specifically targeting early larvae (second- and third-instar). Enhancing the survival of C. chlorideae, especially within hosts, remains a significant technical challenge for large-scale indoor reproduction. This study [...] Read more.
The ichneumonid parasitoid Campoletis chlorideae is an important natural enemy of lepidopteran pests in different agro-ecosystems, specifically targeting early larvae (second- and third-instar). Enhancing the survival of C. chlorideae, especially within hosts, remains a significant technical challenge for large-scale indoor reproduction. This study investigates the use of endogenous serpin-e protein, derived from the host Helicoverpa armigera (Haserpin-e), to improve the survival rate of C. chlorideae in indoor reproduction. The results demonstrated that Haserpin-e protein significantly enhanced cocoon production in C. chlorideae, with no observable adverse effects on the life history traits of both F0 and F1 generations of C. chlorideae. By investigating the mechanism underlying cocoon formation promotion, it was found that Haserpin-e protein reduced the encapsulation, inhibited melanization, as well as suppressed the expression of antimicrobial proteins (AMPs) in H. armigera. This study provides novel insights into improving the survival of C. chlorideae by inhibiting host immune responses through the application of its endogenous Haserpin-e protein during large-scale indoor reproduction efforts. Additionally, this research further elucidates the multifaceted functionality of Haserpin-e proteins by demonstrating their role in regulating innate immune processes in H. armigera, including negatively regulating encapsulation, melanization, and AMP expression. Full article
(This article belongs to the Section Insect Pest and Vector Management)
10 pages, 668 KiB  
Article
Impact of Sulfoxaflor on Brown Marmorated Stink Bug: Developmental and Reproductive Effects
by Ren Li, Zehua Wang, Fan Yang, Tao Su, Guanghang Qiao and Shanning Wang
Insects 2025, 16(5), 465; https://doi.org/10.3390/insects16050465 - 28 Apr 2025
Viewed by 114
Abstract
The brown marmorated stink bug, Halyomorpha halys, has become a severe threat to agriculture worldwide with continuous invasion and spread. Sulfoxaflor is the pioneering sulfoximine insecticide and has been widely employed for managing sap-feeding insect pests across diverse crops. However, the sublethal [...] Read more.
The brown marmorated stink bug, Halyomorpha halys, has become a severe threat to agriculture worldwide with continuous invasion and spread. Sulfoxaflor is the pioneering sulfoximine insecticide and has been widely employed for managing sap-feeding insect pests across diverse crops. However, the sublethal effects of sulfoxaflor on the growth and reproduction of H. halys remain unexplored. This study employed age-stage life tables and physiological parameters to evaluate the sublethal effects of sulfoxaflor on H. halys. The bioassay results indicated that the LC20 and LC50 values of sulfoxaflor against second-instar nymphs of H. halys were 7.75 and 20.97 mg/L, respectively. Treatment with the LC20 concentration of sulfoxaflor reduced the lifespan of female adults by 11.74 days. Importantly, the oviposition period of females was shortened by 9.47 days, and the fecundity was decreased by 1.4-fold. Additionally, the activities of cytochrome P450 (P450s) and glutathione S-transferase (GSTs) enzymes in H. halys were enhanced 1.40 and 1.54 times after treatment with sublethal concentrations of sulfoxaflor. These findings demonstrate that sublethal concentrations of sulfoxaflor significantly inhibit the population development of H. halys. Moreover, the detoxification enzymes P450s and GSTs may be associated with the potential resistance to sulfoxaflor in H. halys. This information provides valuable insights into the application of sulfoxaflor in the management of this pest. Full article
(This article belongs to the Section Insect Pest and Vector Management)
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16 pages, 1987 KiB  
Perspective
A Perspective on the Challenges and Prospects of Realizing the Second Life of Retired EV Batteries
by Prodip K. Das
Batteries 2025, 11(5), 176; https://doi.org/10.3390/batteries11050176 - 28 Apr 2025
Viewed by 311
Abstract
As electric vehicle (EV) adoption continues to surge globally, the question of what to do with retired EV batteries looms large. While these batteries may no longer meet the rigorous demands of automotive use, they often retain a significant portion of their capacity [...] Read more.
As electric vehicle (EV) adoption continues to surge globally, the question of what to do with retired EV batteries looms large. While these batteries may no longer meet the rigorous demands of automotive use, they often retain a significant portion of their capacity and functionality. This has led to growing interest in exploring second-life applications for retired EV batteries, ranging from stationary energy storage to grid stabilization and beyond. However, numerous challenges must be addressed to unlock the full potential of this emerging sector. This paper delves into the key challenges and prospects associated with the second life of retired EV batteries. It examines technical hurdles, such as battery degradation, safety concerns, and the development of efficient repurposing methods, along with regulatory and economic barriers, including standards for battery reuse, recycling infrastructure, and market dynamics. Additionally, it highlights the potential environmental benefits, including reduced carbon emissions and resource conservation. In conclusion, the second life of retired EV batteries presents both challenges and opportunities. Addressing technical, regulatory, and economic barriers will be essential for realizing the full potential of this growing sector. However, with continued innovation and collaboration across industries, the future looks bright for leveraging retired EV batteries to create a more sustainable energy ecosystem. Full article
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17 pages, 242 KiB  
Article
Relationships Between Preservice Teachers’ Interest, Perceived Knowledge, and Argumentation in Socioscientific Issues: Implications for Teaching About the Complexity of Sustainability Challenges
by Pedro Daniel Cadena-Nogales, José Javier Verdugo-Perona, Joan Josep Solaz-Portolés and Vicente Sanjosé
Sustainability 2025, 17(9), 3860; https://doi.org/10.3390/su17093860 - 24 Apr 2025
Viewed by 324
Abstract
Socioscientific issues are a key aspect of science education, enhancing citizens’ understanding of the intricate relationships among global concerns and fostering their engagement in informed decision making on these problems. To this end, teachers must be able to establish connections between scientific content, [...] Read more.
Socioscientific issues are a key aspect of science education, enhancing citizens’ understanding of the intricate relationships among global concerns and fostering their engagement in informed decision making on these problems. To this end, teachers must be able to establish connections between scientific content, its application in everyday life, and its impact on social, economic, and environmental dimensions. This study analyzes the factors that influence teachers’ ability to address these topics in the classroom. It includes two studies. The first study (n = 213) examines prospective science teachers’ interest in and perceived knowledge of 14 issues related to the Sustainable Development Goals (SDGs). The second study (n = 135) analyzes the types of arguments that participants use to justify their interest. A mixed-method ex post facto design was employed, using ad hoc questionnaires. The results suggest significant differences between interest and perceived knowledge across certain specific topics. Additionally, the topic addressed tends to evoke specific dimensions within arguments, with cultural/social and ecological/environmental aspects being the most prevalent, influencing the connections teachers establish with everyday life contexts. These findings highlight how interest, perceived knowledge, and the topic itself influence the dimensions considered in argument construction when discussing socioscientific issues and may contribute to the development of teacher training programs that foster a deeper understanding of the complex nature of these sustainability-related issues. Full article
(This article belongs to the Section Sustainable Education and Approaches)
36 pages, 9920 KiB  
Article
Recovered Tire-Derived Aggregates for Thermally Insulating Lightweight Mortars
by Elhem Ghorbel, Safiullah Omary and Ali Karrech
Materials 2025, 18(8), 1849; https://doi.org/10.3390/ma18081849 - 17 Apr 2025
Viewed by 305
Abstract
This study explores the innovative use of recovered tire-derived aggregates in cement-based mortars to enhance thermal insulation and reduce environmental impact. The research addresses the pressing global challenge of managing end-of-life tires (ELTs), which are non-biodegradable and contribute significantly to waste management issues. [...] Read more.
This study explores the innovative use of recovered tire-derived aggregates in cement-based mortars to enhance thermal insulation and reduce environmental impact. The research addresses the pressing global challenge of managing end-of-life tires (ELTs), which are non-biodegradable and contribute significantly to waste management issues. By incorporating crumb rubber from recycled tires into mortars, this study investigates the feasibility of creating lightweight, thermally insulating mortars suitable for building repair and rehabilitation. The primary objective is to develop mortars that minimize structural load, decrease energy consumption in buildings, and promote the recycling of ELTs as a valuable resource. The study focuses on evaluating how varying crumb rubber content affects key properties such as workability, thermal conductivity, compressive strength, and fracture energy. Experimental tests were conducted to assess these properties, with the results indicating that mortars with up to 50% crumb rubber content exhibit improved thermal insulation and meet industry standards for non-structural repair applications. The methodology involved creating eight different mortar mixtures with varying proportions of crumb rubber particles (ranging from 0% to 100%). Each mixture was tested for physical and mechanical properties, including density, workability, air content, setting time, thermal conductivity, and strength. The experimental results showed that as the crumb rubber content increased, the thermal conductivity of the mortars decreased, indicating enhanced insulation properties. However, higher crumb rubber content led to reduced mechanical strength, highlighting the need for a balanced approach in material design. Key findings reveal that the air content of early-age mortar paste increases linearly with the crumb rubber replacement ratio, impacting the hardened behavior by concentrating stresses or facilitating the infiltration of damaging elements. The study also establishes relationships between mortar properties and crumb rubber content, contributing to the development of sustainable construction materials. The environmental benefits of recycling ELTs are emphasized, as this practice reduces the reliance on natural sand, a resource that is the second most consumed globally after water. This study underscores the viability of using crumb rubber from recycled tires in mortars for repair and rehabilitation purposes. The developed mortars, particularly those with 25% to 50% crumb rubber content, show promise as non-structural repair products, offering improved thermal insulation and reduced environmental impact. Full article
(This article belongs to the Section Construction and Building Materials)
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20 pages, 15674 KiB  
Article
Binder-Free Fe-N-C-O Bifunctional Electrocatalyst in Nickel Foam for Aqueous Zinc–Air Batteries
by Jorge González-Morales, Jadra Mosa and Mario Aparicio
Batteries 2025, 11(4), 159; https://doi.org/10.3390/batteries11040159 - 17 Apr 2025
Viewed by 186
Abstract
The development of efficient, sustainable, and cost-effective catalysts is crucial for energy storage technologies, such as zinc–air batteries (ZABs). These batteries require bifunctional catalysts capable of efficiently and selectively catalyzing oxygen redox reactions. However, the high cost and low selectivity of conventional catalysts [...] Read more.
The development of efficient, sustainable, and cost-effective catalysts is crucial for energy storage technologies, such as zinc–air batteries (ZABs). These batteries require bifunctional catalysts capable of efficiently and selectively catalyzing oxygen redox reactions. However, the high cost and low selectivity of conventional catalysts hinder the large-scale integration of ZABs into the electric grid. This study presents binder-free Fe-based bifunctional electrocatalysts synthesized via a sol–gel method, followed by thermal treatment under ammonia flow. Supported on nickel foam, the catalyst exhibits enhanced activity for both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), essential for ZAB operation. This work addresses two critical challenges in the development of ZABs: first, the replacement of costly cobalt or platinum-group-metal (PGM)-based catalysts with an efficient alternative; second, the achievement of prolonged battery performance under real conditions without passivation. Structural analysis confirms the integration of iron nitrides, oxides, and carbon, resulting in high conductivity and catalytic stability without relying on precious or cobalt-based metals. Electrochemical tests reveal that the catalyst calcined at 800 °C delivers superior performance, achieving a four-electron ORR mechanism and prolonged operational life compared to its 900 °C counterpart. Both catalysts outperform conventional Pt/C-RuO2 systems in stability and selective bifunctionality, offering a more sustainable and cost-effective alternative. The innovative combination of nitrogen, carbon, and iron compounds overcomes limitations associated with traditional materials, paving the way for scalable, high-performance applications in renewable energy storage. This work underscores the potential of transition metal-based catalysts in advancing the commercial viability of ZABs. Full article
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31 pages, 5064 KiB  
Article
Tool for Greener Tourism: Evaluating Environmental Impacts
by Cristina Campos Herrero, Ana Cláudia Dias, María Gallego, David Gutiérrez, Paula Quinteiro, Pedro Villanueva-Rey, Sara Oliveira, Jaume Albertí, Alba Bala, Pere Fullana-i-Palmer, Margalida Fullana Puig, Lela Melón, Ilija Sazdovski, Eduardo Rodríguez, Mercè Roca, Ramon Xifré, Jara Laso Cortabitarte, María Margallo Blanco and Rubén Aldaco García
Sustainability 2025, 17(8), 3476; https://doi.org/10.3390/su17083476 - 14 Apr 2025
Viewed by 779
Abstract
Travel and tourism are essential to global economies, generating social, economic, and environmental impacts. However, there is a lack of standardized methodologies to assess the environmental footprint of tourist destinations beyond carbon footprint analysis. This study introduces the Greentour tool, the first of [...] Read more.
Travel and tourism are essential to global economies, generating social, economic, and environmental impacts. However, there is a lack of standardized methodologies to assess the environmental footprint of tourist destinations beyond carbon footprint analysis. This study introduces the Greentour tool, the first of its kind to evaluate the environmental impact of accommodation, restaurants, and tourism activities using nine environmental indicators from a life cycle assessment (LCA) perspective. The tool applies a hybrid bottom-up and top-down approach, integrating data from tourist establishments and destination managers. The tool was tested in four tourist destinations in Spain and Portugal (Rías Baixas, Camino Lebaniego, Lloret de Mar, and Guimarães), revealing that transportation is the primary contributor to environmental impacts, ranging from 60% to 96% of total emissions, particularly in air-travel-dependent destinations. Food and beverage services are the second-largest contributor, accounting for up to 26% of emissions, while accommodation ranks third (1–14%). This study highlights the significant role of electricity consumption and food choices (e.g., red meat and dairy) in greenhouse gas (GHG) emissions, emphasizing the need for sustainable alternatives. Despite challenges in data collection, particularly for food and transport statistics, the Greentour tool has demonstrated robustness and adaptability across diverse destinations, making it applicable worldwide. This tool provides key insights for policymakers, tourism stakeholders, and businesses, supporting the integration of sustainability strategies into public policies and industry best practices. Future research should focus on expanding its use to additional destinations to foster science-based decision-making and promote more sustainable tourism practices globally. Full article
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40 pages, 2834 KiB  
Review
Sustainable Recycling of End-of-Life Electric Vehicle Batteries: EV Battery Recycling Frameworks in China and the USA
by Amjad Ali, Mujtaba Al Bahrani, Shoaib Ahmed, Md Tasbirul Islam, Sikandar Abdul Qadir and Muhammad Shahid
Recycling 2025, 10(2), 68; https://doi.org/10.3390/recycling10020068 - 10 Apr 2025
Viewed by 613
Abstract
The increasing adoption of electric vehicles (EVs) has led to a surge in end-of-life (EOL) lithium-ion batteries (LIBs), necessitating efficient recycling strategies to mitigate environmental risks and recover critical materials. This study compares the EV battery recycling frameworks in China and the United [...] Read more.
The increasing adoption of electric vehicles (EVs) has led to a surge in end-of-life (EOL) lithium-ion batteries (LIBs), necessitating efficient recycling strategies to mitigate environmental risks and recover critical materials. This study compares the EV battery recycling frameworks in China and the United States, focusing on policy effectiveness, technological advancements, and material recovery efficiencies. China’s extended producer responsibility (EPR) policies and 14th Five-Year Plan mandate strict recycling targets, achieving a 40% battery recycling rate with 90% material recovery efficiency. Hydrometallurgical methods dominate, reducing energy consumption by 50% compared to virgin material extraction. The US, leveraging incentive-based mechanisms and private sector innovations, has a 35% recycling rate but a higher 95% resource recovery efficiency, mainly due to direct recycling and AI-based sorting technologies. Despite these advancements, challenges remain, including high recycling costs, inconsistent global regulations, and supply chain inefficiencies. To enhance sustainability, this study recommends harmonized international policies, investment in next-generation recycling technologies, and second-life battery applications. Emerging innovations, such as AI-driven sorting and direct cathode regeneration, could increase recovery efficiency by 20–30%, further reducing lifecycle costs. By integrating synergistic policies and advanced recycling infrastructures, China and the US can set a global precedent for sustainable EV battery management, driving the transition toward a circular economy. Future research should explore life cycle cost analysis and battery reuse strategies to optimize long-term sustainability. Full article
(This article belongs to the Special Issue Lithium-Ion and Next-Generation Batteries Recycling)
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18 pages, 2508 KiB  
Article
Comparison of Thermochemical Conversion Processes for Antibiotic Residues: Insights from Life Cycle Assessment
by Jian Yang, Yulian Wei, Rui Ma, Hongzhi Ma, Biqin Dong and Ying Wang
Processes 2025, 13(4), 1139; https://doi.org/10.3390/pr13041139 - 10 Apr 2025
Viewed by 314
Abstract
Life cycle assessment (LCA) was conducted to evaluate the environmental impacts and health risks associated with four thermochemical conversion technologies: incineration, gasification, pyrolytic liquefaction, and hydrothermal liquefaction. Results revealed that all processes yielded positive net environmental benefits (3.8–8.2 kg CO2-eq/kg AR [...] Read more.
Life cycle assessment (LCA) was conducted to evaluate the environmental impacts and health risks associated with four thermochemical conversion technologies: incineration, gasification, pyrolytic liquefaction, and hydrothermal liquefaction. Results revealed that all processes yielded positive net environmental benefits (3.8–8.2 kg CO2-eq/kg AR reduction), with hydrothermal liquefaction exhibiting the lowest emissions (GWP-5.71 kg CO2-eq/kg). However, its widespread application has been hindered by process limitations, and enhancing catalytic efficiency has been identified as a critical area for future research. Incineration ranked second in terms of environmental benefits and remains the most favorable method according to existing studies. In contrast, gasification and pyrolytic liquefaction did not demonstrate significant environmental advantages, primarily due to the high energy consumption required for drying. Consequently, optimizing the drying process has been highlighted as a key focus for future research efforts. This study provided valuable insights for the safe disposal and resource recovery of antibiotic residue. Full article
(This article belongs to the Special Issue Research on Biomass Energy and Resource Utilization Technology)
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14 pages, 3455 KiB  
Article
Effect of Cr Doping on Microstructure and Hydrogen Storage Properties of Zr0.8Ti0.2CrxCo1−x (x = 0, 0.05, 0.1, 0.15) Alloys
by Feng Wang, Wenting Liu, Lina Liang, Yue Liu, Zhengru Huang, Maohua Rong, Jiageng Liu, Wei Lv, Shuai Ji and Jiang Wang
Processes 2025, 13(4), 1026; https://doi.org/10.3390/pr13041026 - 30 Mar 2025
Viewed by 271
Abstract
The ZrCo hydrogen storage alloy is a relatively good hydrogen isotope carrier applied in the National Thermonuclear Fusion Reactor. However, the intrinsic disproportionation characteristics of ZrCo alloy reduces its cyclic service life and limits its further application. To address this issue, Zr0.8 [...] Read more.
The ZrCo hydrogen storage alloy is a relatively good hydrogen isotope carrier applied in the National Thermonuclear Fusion Reactor. However, the intrinsic disproportionation characteristics of ZrCo alloy reduces its cyclic service life and limits its further application. To address this issue, Zr0.8Ti0.2Co alloy is developed and exhibits good anti-disproportionation performance than pure ZrCo. Nevertheless, Zr0.8Ti0.2Co suffers from relatively poor hydrogen absorption kinetics. In this study, the effects of Cr substitution on its microstructure and hydrogen storage performance are investigated. Zr0.8Ti0.2CrxCo1−x (x = 0, 0.05, 0.1, 0.15) samples are composed of the ZrCo main phase. After Cr substitution, the second phases of CoZr2 and TiCr2 Laves phases appear. With the increase in Cr content, the lattice constant and unit cell volume of the Zr0.8Ti0.2Co alloy increase. Meanwhile, the hydrogen absorption incubation time of the Zr0.8Ti0.2Co alloy is shortened, and the activation performance is enhanced, which is attributed to the catalytic effect of the Laves second phases. The enthalpy of hydrogen absorption of the Zr0.8Ti0.2Co alloy increases, and the stability of the hydride is enhanced with increasing Cr addition. Zr0.8Ti0.2Cr0.05Co0.95 demonstrates excellent hydrogen desorption kinetics while maintaining robust anti-disproportionation performance. The element substitution and the composition design are effective approaches to improving the comprehensive hydrogen storage performance of ZrCo-based alloys, which provides guidance for its further application. Full article
(This article belongs to the Special Issue Digital Research and Development of Materials and Processes)
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21 pages, 6013 KiB  
Article
Very-Large-Scale Integration-Friendly Method for Vital Activity Detection with Frequency-Modulated Continuous Wave Radars
by Krzysztof Ślot, Piotr Łuczak, Paweł Kapusta, Sławomir Hausman, Arto Rantala and Jacek Flak
Sensors 2025, 25(7), 2151; https://doi.org/10.3390/s25072151 - 28 Mar 2025
Viewed by 253
Abstract
A simple algorithm for respiratory activity detection in data produced by Frequency-Modulated Continuous-Wave (FMCW) radars is presented in this paper. The proposed computational architecture can be directly mapped onto custom digital–analog VLSI hardware, which is a unique approach in research on intelligent FMCW [...] Read more.
A simple algorithm for respiratory activity detection in data produced by Frequency-Modulated Continuous-Wave (FMCW) radars is presented in this paper. The proposed computational architecture can be directly mapped onto custom digital–analog VLSI hardware, which is a unique approach in research on intelligent FMCW sensor development, offering a potential energy-efficient data analysis solution for target applications, such as preventing human trafficking or providing life-sign detection under limited visibility. The algorithm comprises two main modules. The first one summarizes radar-produced data into a descriptor reflecting the amount of motion that occurs within appropriately determined time intervals. The second one classifies a sequence of the produced descriptors using a recurrent neural network composed of gated recurrent units. To ensure the algorithm’s implementation feasibility, an analog VLSI circuit comprising its main functional blocks has been designed, manufactured, and tested, providing constraints for neural model derivation. The adverse effects of the primary constraint, the severe restriction on admissible weight resolution, have been handled by introducing a novel training loss component and a simple mechanism for diversifying the effective weight sets of different network neurons. Experimental evaluation of the presented method, performed using the dataset of indoor recordings, indicates that the proposed simple, hardware implementation-friendly algorithm provides over 94% human detection accuracy and similar F1 scores. Full article
(This article belongs to the Collection Artificial Intelligence in Sensors Technology)
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17 pages, 1167 KiB  
Article
Preprocessing-Free Convolutional Neural Network Model for Arrhythmia Classification Using ECG Images
by Chotirose Prathom, Ryuhi Fukuda, Yuto Yokoyanagi and Yoshifumi Okada
Technologies 2025, 13(4), 128; https://doi.org/10.3390/technologies13040128 - 26 Mar 2025
Viewed by 323
Abstract
Arrhythmia, which is characterized by irregular heart rhythms, can lead to life-threatening conditions by disrupting the circulatory system. Thus, early arrhythmia detection is crucial for timely and appropriate patient treatment. Machine learning models have been developed to classify arrhythmia using electrocardiogram (ECG) data, [...] Read more.
Arrhythmia, which is characterized by irregular heart rhythms, can lead to life-threatening conditions by disrupting the circulatory system. Thus, early arrhythmia detection is crucial for timely and appropriate patient treatment. Machine learning models have been developed to classify arrhythmia using electrocardiogram (ECG) data, which effectively capture the patterns associated with different abnormalities and achieve high classification performance. However, these models face challenges in terms of input coverage and robustness against data imbalance issues. Typically, existing methods employ a single cardiac cycle as the input, possibly overlooking the intervals between cycles, potentially resulting in the loss of critical temporal information. In addition, limited samples for rare arrhythmia types restrict the involved model’s ability to effectively learn, frequently resulting in low classification accuracy. Furthermore, the classification performance of existing methods on unseen data is not satisfactory owing to insufficient generalizability. To address these limitations, this research proposes a convolutional neural network (CNN) model for arrhythmia classification that incorporates two specialized modules. First, the proposed model utilizes images of three consecutive cardiac cycles as the input to expand the learning scope. Second, we implement a focal loss (FL) function during model training to prioritize minority classes. The experimental results demonstrate that the proposed model outperforms existing methods without requiring data preprocessing. The integration of multicycle ECG images and the FL function substantially enhances the model’s ability to capture ECG patterns, particularly for minority classes. In addition, our model exhibits satisfactory classification performance on unseen data from new patients. These findings suggest that the proposed model is a promising tool for practical application in arrhythmia classification tasks. Full article
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21 pages, 12241 KiB  
Article
A Social Assistance System for Augmented Reality Technology to Redound Face Blindness with 3D Face Recognition
by Wen-Hau Jain, Bing-Gang Jhong and Mei-Yung Chen
Electronics 2025, 14(7), 1244; https://doi.org/10.3390/electronics14071244 - 21 Mar 2025
Viewed by 418
Abstract
The objective of this study is to develop an Augmented Reality (AR) visual aid system to help patients with prosopagnosia recognize faces in social situations and everyday life. The primary contribution of this study is the use of 3D face models as the [...] Read more.
The objective of this study is to develop an Augmented Reality (AR) visual aid system to help patients with prosopagnosia recognize faces in social situations and everyday life. The primary contribution of this study is the use of 3D face models as the basis of data augmentation for facial recognition, which has practical applications for various social situations that patients with prosopagnosia find themselves in. The study comprises the following components: First, the affordances of Active Stereoscopy and stereo cameras were combined. Second, deep learning was employed to reconstruct a detailed 3D face model in real-time based on data from the 3D point cloud and the 2D image. Data were also retrieved from seven angles of the subject’s face to improve the accuracy of face recognition from the subject’s profile and in a range of dynamic interactions. Second, the data derived from the first step were entered into a convolutional neural network (CNN), which then generated a 128-dimensional characteristic vector. Next, the system deployed Structured Query Language (SQL) to compute and compare Euclidean distances to determine the smallest Euclidean distance and match it to the name that corresponded to the face; tagged face data were projected by the camera onto the AR lenses. The findings of this study show that our AR system has a robustness of more than 99% in terms of face recognition. This method offers a higher practical value than traditional 2D face recognition methods when it comes to large-pose 3D face recognition in day-to-day life. Full article
(This article belongs to the Special Issue Real-Time Computer Vision)
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24 pages, 4738 KiB  
Article
Framework for Selecting the Most Effective State of Health Method for Second-Life Lithium-Ion Batteries: A Scientometric and Multi-Criteria Decision Matrix Approach
by AbdulRahman Salem, Basil M. Darras and Mohammad Nazzal
Energies 2025, 18(6), 1527; https://doi.org/10.3390/en18061527 - 19 Mar 2025
Viewed by 264
Abstract
The predicted rapid accumulation of end-of-life lithium-ion batteries (LIBs) from electric vehicles (EVs) has raised environmental concerns due to the toxic nature of LIB materials. Consequently, researchers have developed reusing and recycling plans for end-of-life LIBs to extend their life spans, mitigate residual [...] Read more.
The predicted rapid accumulation of end-of-life lithium-ion batteries (LIBs) from electric vehicles (EVs) has raised environmental concerns due to the toxic nature of LIB materials. Consequently, researchers have developed reusing and recycling plans for end-of-life LIBs to extend their life spans, mitigate residual capacity loss, and reduce their environmental impact. As a result, many studies have recommended establishing a lifecycle framework for LIBs to identify and manage the potential options for reusing, recycling, remanufacturing, or disposal of second life LIBs. In response, the state of health (SOH) and state of safety (SOS) methods were introduced as key performance indicators (KPIs) to determine the batteries’ health and usability based on their capacity levels. Thus, both SOH and SOS methods are crucial for battery cell selection frameworks employed to designate batteries’ second-life applications. Various papers have analyzed and compared SOH methods, yet none have clearly quantified their differences, to determine the most effective method. Therefore, this study aims to create a framework for selecting the most effective SOH method for use in LIB frameworks by identifying and quantifying their main KPIs. The proposed framework will utilize scientometric analysis to identify the KPIs necessary for a gray relation analysis (GRA)-based multi-criteria decision matrix (MCDM) to select the appropriate SOH method. Full article
(This article belongs to the Section D2: Electrochem: Batteries, Fuel Cells, Capacitors)
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