IEEE Access最新文献

{"title":"Quantification of Task-Dependent Leg Muscle Synergy Patterns During Isometric Force Generation Tasks in a Seated Position Among Healthy Older Individuals","authors":"Duguma Teshome Gemechu;Eunyoung Seo;Olga V. Kim;Song Joo Lee","doi":"10.1109/ACCESS.2025.3604416","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3604416","url":null,"abstract":"The generation of isometric forces in the legs, which require the activation of combined muscle groups as muscle synergy, is essential during various daily activities. However, there is a lack of information on whether task-dependent leg muscle synergy patterns exist in a seated position. Thus, this study aimed to investigate whether task-dependent leg muscle synergy patterns exist in simplified direction-specific force generation tasks (FGT) on the sagittal and frontal planes in healthy older individuals. Thirteen healthy old individuals were seated with their hips and knees flexed at 90° on a customized lower limb force-measuring device. They generated isometric force in response to visual cues presented in anterior, posterior, lateral, and medial directions. Simultaneously, muscle activities from nine muscles in the same leg were obtained. Peak forces significantly differed across the four directions (p<0.05). Three muscle synergies accounted for 95% of the variance in electromyographic (EMG) data during the FGTs. Muscle synergies exhibited high reliability across subjects, with an average intraclass correlation coefficient (ICC) of 0.91 and a 95% confidence interval of 0.8-0.98 (p<0.001). Each muscle synergy had a significantly different preferred direction (PD) angle in degrees (p<0.01). Peak EMG activity of the quadriceps, hamstrings, and adductor muscles also exhibited significant differences across directions (p<0.05, p<0.01, and p<0.001, respectively). Our findings and approach may provide the foundation for developing an evaluation tool to plan targeted rehabilitation for individuals with neuromuscular disorders during the early stage of their rehabilitation or for older individuals when walking is not feasible.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"153638-153650"},"PeriodicalIF":3.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11145816","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145027937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Study on the Generalization Ability of Machine Learning and Deep Learning Algorithms for Quality Assessment of Wearable PPG Recordings","authors":"Santiago Mula Muñoz;Roberto Zangróniz;Óscar Ayo-Martín;José Joaquín Rieta;Raúl Alcaraz","doi":"10.1109/ACCESS.2025.3604652","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3604652","url":null,"abstract":"One of the major challenges in using photoplethysmography (PPG) sensors for heart rate monitoring in real-world settings is ensuring signal quality. This work evaluates and compares quality assessment methods using generic machine learning (ML) and deep learning (DL) pipelines, on a unique and comprehensive framework that includes different sensors, wavelengths, measurement locations, and recording environments. The PPG signals from one proprietary and five publicly available datasets were labeled in terms of quality by comparing the PPG-derived heart rate to a reference heart rate estimated from simultaneous electrocardiograms. Diverse techniques based on common ML classifiers and one- and two-dimensional convolutional neural networks (CNN) were trained on a dataset and tested on the remaining ones. The results showed that several generated models performed comparably to previous studies when they were tested on datasets with similar measurement positions and sensors to the training database. Specifically, reductions in sensitivity, specificity, and F1-score of less than 3% from training to testing were observed on some methods. Contrarily, they reported a notably poorer performance when tested on datasets presenting conditions different from the training. Even the best-performing model, based on the well-known, pre-trained CNN AlexNet, experienced a performance drop of over 20% in that situation. These findings show that the analyzed ML and DL methods lack the ability to generalize across PPG signals captured from diverse environments, sensors, wavelengths, and measurement locations. This suggests that developing case-specific methods might be the shortest path towards reliable PPG quality assessment.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"154031-154045"},"PeriodicalIF":3.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11145778","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145021196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multimodal Analysis of Emotional and Visual Responses to Urban Green Spaces in Virtual Environments","authors":"Chong Liu;Tzu-Yang Wang;Takaya Yuizono","doi":"10.1109/ACCESS.2025.3604420","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3604420","url":null,"abstract":"Urban green spaces (UGSs) play a vital role in promoting emotional well-being and supporting public health. Emotional responses to landscapes are closely linked to visual behavior, reflecting how individuals engage with environmental features. This study proposes and applies a multimodal sensing framework to examine how the types and proportions of landscape elements influence emotional and visual responses in immersive virtual environments. Sixty participants experienced 360° panoramic simulations of three UGS types—urban parks, community gardens, and ecological wetlands—featuring seven landscape elements: trees, shrubs, flowering trees, grass, herb plants, water landscapes, and artificial objects. Data were collected using electrodermal activity (EDA), pulse rate (PR), eye-tracking metrics, and self-reported emotional ratings. Visual behavior indices were analyzed in relation to landscape composition. Results show that both visual behavior and emotional responses were significantly influenced by landscape elements. Herb plants enhanced attention and positive emotions across compositions. Flowering trees exhibited a dual effect—eliciting physiological arousal while promoting relaxation. Water landscapes captured immediate attention and evoked positive emotional experiences, whereas artificial objects required greater visual effort but yielded limited emotional benefits. These findings provide actionable, data-driven insights for the design of emotionally supportive UGSs in high-density environments.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"152890-152902"},"PeriodicalIF":3.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11145757","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145036822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hashgraph Over the Edge: Achieving Byzantine Fault Tolerance in Decentralized P2P Frameworks","authors":"Wanli Zhao;Satoshi Fujita","doi":"10.1109/ACCESS.2025.3604512","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3604512","url":null,"abstract":"This paper explores the integration of the Hashgraph consensus protocol into two widely used peer-to-peer (P2P) communication frameworks: Secure Scuttlebutt (SSB) and libp2p. SSB operates within a local-first architecture, prioritizing offline-first data synchronization through append-only logs and gossip-based replication, while libp2p employs a modular, pub-sub-driven approach to facilitate real-time message dissemination across decentralized networks. We propose a dual integration approach, embedding an asynchronous Byzantine fault-tolerant (aBFT) layer into both frameworks to evaluate their complementary strengths in diverse networking scenarios. This dual-path strategy allows us to investigate how Hashgraph’s aBFT properties interact with fundamentally different P2P architectures—append-only, local-first versus modular, pub-sub—thus offering a broader understanding of its applicability. Our goal is to enhance their ability to achieve a globally consistent state despite the challenges of intermittent connectivity and network partitions. To assess the feasibility and performance implications of this integration, we conduct a series of controlled experiments using Docker-based network simulations. Our evaluation focuses on key trade-offs involving consistency, latency, and bandwidth utilization. The results show that SSB+Hashgraph achieves strong eventual consistency, ensuring robust data integrity even under adversarial conditions. However, this comes at the cost of increased message propagation latency, due to the bulk gossip overhead inherent in SSB’s replication model. In contrast, libp2p+Hashgraph enables significantly faster message propagation through its pub-sub mechanism, but incurs higher bandwidth consumption as more frequent state updates are required to maintain consensus. Notably, our experiments confirm that the proposed approach successfully maintains consensus even in the presence of up to 25% malicious nodes, highlighting its resilience and strong Byzantine fault tolerance. These findings demonstrate the practical viability of combining gossip-based data replication with aBFT consensus to improve the reliability and scalability of decentralized applications. Moreover, our study offers valuable insights into the trade-offs involved in designing resilient P2P communication systems capable of operating efficiently across heterogeneous network environments.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"153035-153055"},"PeriodicalIF":3.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11145446","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144998115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IMU-Based Systems For Skiing Sports: A Scoping Review","authors":"Claudia Presicci;Igor Ingegnosi;Paolo Dondero;Maura Casadio;Camilla Pierella","doi":"10.1109/ACCESS.2025.3604571","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3604571","url":null,"abstract":"Inertial sensor (IMU)-based wearable systems are the most employed technology to acquire in-field information about athletic gesture in skiing sports since they are portable, easy to setup, not bulky and they are compliant with this sport’s extreme conditions, i.e. on-snow measurements, borderless working area. This scoping review wants to map the current scientific works on IMU-based wearable systems in the skiing contexts with the peculiarity of being used in the field: what type of information can be obtained, taking into account number and body position of the inertial sensors, whether other kind of sensors are involved and which type of data analyses techniques applied. A search on various databases identified 134 publications from 2013 to 2025, of which 39 met the inclusion criteria. Three main application areas emerged: 1) skier kinematics characterization, particularly the reconstruction of center of mass and joint trajectories; 2) classification tasks, such as automatic detection of skiing techniques, movement phases, and skier performance levels; and 3) injury prevention and rehabilitation monitoring, including applications in Paralympic skiing. While the reported findings are promising, research in this domain would benefit from deeper investigations, larger participant samples, and standardized protocols, to allow generalization and support the development of robust, field-deployable systems.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"152430-152451"},"PeriodicalIF":3.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11145904","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145005517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Fully Capacitive Transformer Device for Galvanic Isolation Applications","authors":"João Francisco Justo;Wesley Beccaro;Antonio Mendes de Oliveira Neto;Alexandre Maniçoba de Oliveira","doi":"10.1109/ACCESS.2025.3604635","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3604635","url":null,"abstract":"Galvanic isolation is commonly utilized in power transmission and data communication. Studies have explored inductive and electromagnetic coupling for isolation between nearby circuits, while optocoupler devices employ modulated light for data transmission. However, isolation devices have inherent limitations, such as restricted bandwidth, susceptibility to temperature variations, and long-term degradation. These challenges underscore the need for alternative methods to enable reliable and efficient bidirectional data exchange in isolated circuits. We developed a fully capacitive transformer device, based on mutual capacitance, which provides good linear properties across a wide range of frequencies, as well as stability with temperature variations. A model transformer was characterized using circuit analysis and experiments, confirming the physical properties of the device. Then, a functional device was built and applied to provide galvanic isolation between circuits with two different voltage levels. Finally, the device was explored in the configuration with maximum power transfer, using inductors to improve the coupling.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"153764-153772"},"PeriodicalIF":3.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11145447","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145021251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Impact of Combining Datasets on the Robustness of Deep Learning Architectures: A Cross-Dataset Analysis","authors":"Ricardo Buettner;Susan Bertram;Leopold Fischer-Brandies","doi":"10.1109/ACCESS.2025.3604689","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3604689","url":null,"abstract":"Convolutional Neural Networks have become a widely used technology. Typically, the performance of CNN models is measured using an accuracy score obtained on a single dataset. This often results in systems that perform significantly worse in real-world applications. The robustness of the model to unseen environments is still underresearched. Specifically, a research gap remains on how training data affects the robustness of deep learning systems. This research article investigates the impact of combining data in training datasets on the robustness and performance of deep learning models through a cross-dataset analysis. We employ a transfer learning approach to train deep learning models based on four popular architectures and two different datasets, as well as a combination of both datasets. Our results demonstrate that combining two datasets can improve robustness, but the specific effects on performance can vary between architectures, leading to a slight decrease in accuracy in most observed cases, or even an accuracy gain. Furthermore, we find that training on more complex datasets tends to outperform training on simpler datasets in cross-evaluation settings, indicating that models trained on more complex training datasets are more robust. However, we also observe that a simpler architecture fails to generalize when trained on the combined training data, indicating the need for caution and extensive evaluation when combining datasets during the development cycle of deep learning systems.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"151993-152009"},"PeriodicalIF":3.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11145443","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144997977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Novel Approach for Mitigating Class Imbalance in Arabic Text Classification","authors":"Emad Nabil;Abdelrahman Ezzeldin Nagib;Mena Hany;Safiullah Faizullah;Wael Hassan Gomaa","doi":"10.1109/ACCESS.2025.3604427","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3604427","url":null,"abstract":"Natural language processing (NLP) has become somewhat well-known because of its many uses; deep neural networks have driven major developments. Still, there are difficulties, especially in Arabic NLP, where the language’s large vocabulary of over 12 million words and several dialects cause special issues. Arabic has a large speaker base; however, NLP studies in this language find challenges, particularly with class imbalance. Many times, standard class balancing methods overlook intra-class similarity, a crucial element influencing model training. We present a new approach for computing intra-class similarity using cosine similarity and embedding models to find ideal class weights for model training, hence bridging this difference. On two benchmark datasets—the Arabic Semantic Question Similarity dataset (NSURL) and the Microsoft Research Paragraph Corpus (MRPC)—we assessed the proposed approach. With an accuracy of state-of-the-art 83.25% on the MRPC dataset and 96.931% on the NSURL dataset, the proposed approach proved successful in improving model performance in Arabic text classification.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"152870-152889"},"PeriodicalIF":3.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11145759","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144998244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic Thermal Digital Twin of Liquid-Immersed Power Transformer","authors":"Zoran Radakovic;Patrick Picher;Marko Novkovic;Federico Torriano","doi":"10.1109/ACCESS.2025.3604720","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3604720","url":null,"abstract":"This paper presents the application of a detailed dynamic thermal-hydraulic network model (DTHNM) to real liquid-immersed power transformers (LIPTs). Unlike existing simple models based on ordinary differential equations (ODEs), such as those described in the standards, the DTHNM is deeply rooted in physics and resolves many key issues, such as distributed heat accumulation, the dependency of losses on tap position, load, and conductor temperature, as well as the influence of ambient temperature and the various cooling equipment operating stages. The DTHNM provides a time-varying global distribution of liquid flow inside the transformer tank and the distribution of flows and temperatures across each transformer part. It is validated here using field data from a three-phase 66-MVA transformer (summer and winter operating periods) and a single-phase 370-MVA transformer (60-hour extended temperature rise test). The DTHNM closely matches the measured temperatures, whereas standard models show larger errors, especially under high-load and/or low-ambient conditions. The main contributions of this paper are: 1) extension of the detailed steady-state thermal-hydraulic network model (steady-state THNM) to a detailed dynamic model for digital twin applications; 2) application of the model to large LIPTs with validation against measurements; 3) comparison of DTHNM accuracy with that of IEC and IEEE loading guide models; 4) analysis of practical issues including data requirements, computation time, real-time feasibility and limitations.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"153308-153319"},"PeriodicalIF":3.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11145813","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145027914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soundy: A Multimodal Audio Interface for Educational Music Production","authors":"Pietro Buccellato;Andrea Bianco;Cristina Rottondi","doi":"10.1109/ACCESS.2025.3604631","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3604631","url":null,"abstract":"Multimodal interaction has emerged as a promising approach to enrich user experience and foster engagement in Educational Music Production (EMP) environments. Traditional audio interfaces and Digital Audio Workstations (DAWs), while powerful, often present engagement challenges, particularly for beginners, and tend to limit opportunities for spontaneous creativity and hands-on exploration during the learning process. To overcome these limitations, this paper introduces Soundy, a multimodal audio interface that integrates an on-board, lightweight web-based DAW. The system is accessible via a standard browser through a Local Area Network (LAN) and allows users to control audio production tasks using predefined and custom voice and facial commands. A comparative within-subject study was conducted involving 20 participants, each of whom tested both Soundy and a standard configuration composed of a Behringer UMC404HD audio interface and the Reaper DAW. The evaluation focused on two key dimensions, usability and engagement, measured using two standardized and validated instruments: The Post-Study System Usability Questionnaire (PSSUQ) and the User Engagement Scale - Short Form (UES-SF), complemented by open-ended participant feedback. Results revealed a trade-off between configurations: the standard setup ensured higher usability and task efficiency, while Soundy promoted greater engagement, creativity, and exploratory behavior. These findings suggest that embedded multimodal solutions based on voice and facial interaction hold strong potential for enhancing student experience in EMP and support future developments in adaptive command recognition and integrated hardware design.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"153105-153122"},"PeriodicalIF":3.6,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11145444","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144998031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}