IEEE Access最新文献

{"title":"Synthesis of Variable Gain Robust State Observer for Linear Systems With Structured Uncertainties","authors":"Kazuhiro Hirasawa;Hayate Sawato;Daiki Asada;Hidetoshi Oya","doi":"10.1109/ACCESS.2025.3563214","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3563214","url":null,"abstract":"This paper proposes a new variable gain robust state observer for a class of linear uncertain systems. The variable gain robust state observer proposed in this paper consists of fixed observer gain matrices and nonlinear modification functions which are determined by appropriate updating rules. It is shown that sufficient conditions for the existence of the proposed variable gain robust state observer can be reduced to solvability of Linear Matrix Inequalities (LMIs). Finally, we give simple numerical examples so as to illustrate the effectiveness of the proposed variable gain robust state observer.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"75319-75327"},"PeriodicalIF":3.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10976547","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143902699","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":"Bayesian Analysis Enhances Sales and Warranty Strategies for Repairable Industrial Products by Considering Hybrid Deterioration Modes","authors":"Chih-Chiang Fang;Liping Ma;Wenfeng Kuo","doi":"10.1109/ACCESS.2025.3563938","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3563938","url":null,"abstract":"An effective warranty policy not only fulfills a manufacturer’s or vendor’s obligations but also plays a crucial role in enhancing customer confidence and encouraging future purchases. To attract more customers and drive sales, companies may extend the service life of their products. However, they cannot offer unlimited warranties to dominate the market, as the associated warranty costs will ultimately outweigh the profits. Therefore, manufacturers must strike a balance between the advantages of providing longer warranties to foster customer trust and the potential financial implications involved. Despite the significance of this issue, there has been limited research on hybrid deteriorating systems that encompass both maintainable and non-maintainable failure modes. Furthermore, conducting preventive maintenance analyses is challenging when historical failure data is insufficient. To address these gaps, this study introduces a Bayesian statistical approach to handle preventive maintenance challenges. The system’s deterioration is modeled using Non-Homogeneous Poisson processes (NHPP) with power-law failure intensity functions. A mathematical model, along with a solution algorithm, has been developed to assist manufacturers in making informed decisions regarding pricing, production, and warranty strategies. Furthermore, to facilitate the practical application of these models, the study offers solution algorithms and a computerized framework that enables decision-makers to implement automated decision-making processes.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"72169-72188"},"PeriodicalIF":3.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10975777","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143902713","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":"Design and Comprehensive Analysis of Magnetic-Geared Permanent Magnet Synchronous Motor for Single-Propeller Underwater Propulsion","authors":"Jang-Hyun Park;Do-Kwan Hong","doi":"10.1109/ACCESS.2025.3564241","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3564241","url":null,"abstract":"This paper presents a magnetic-geared permanent magnet synchronous motor (MG-PMSM), which is an integrated structure composed of a permanent magnet synchronous motor (PMSM) and a magnetic gear (MG) for autonomous underwater vehicles (AUVs). The MG-PMSM features a dual rotor structure: a high-speed permanent magnet rotor (PMR) and a low-speed pole piece rotor (PPR). To meet the required load conditions of the single propeller of the AUV, the PPR, directly connected to the output shaft, operates under load conditions, while the PMR operates under no-load conditions. The aim of this study is to use finite element analysis (FEA) to investigate the overall electromagnetic performance of the proposed MG-PMSM with different gear ratios and slot/pole combinations. Subsequently, a structural analysis of the PPR and its support structure is conducted using FEA to validate the strength of the PPR structure. Furthermore, thermal analysis is performed using computational fluid dynamics. The results of the structural and thermal analyses demonstrate sufficient structural strength and thermal stability, respectively. Finally, the electromagnetic performances of the proposed MG-PMSM are compared with the PMSM and MG configuration. The results show that, although the MG-PMSM exhibits nearly identical efficiency, it achieves an 11.4% increase in volumetric torque density per unit active volume compared to the PMSM and MG configuration. Moreover, when accounting for the inactive volume of the integrated underwater propulsion system, the volumetric torque density is expected to increase further.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"73486-73497"},"PeriodicalIF":3.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10976355","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143902648","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":"An Interpretable Combined Forecasting Method for Stock Market Based on Fuzzy Time Series Model and Linear-Trend Fuzzy Information Granulation","authors":"Jindong Feng;Zengtai Gong","doi":"10.1109/ACCESS.2025.3564135","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3564135","url":null,"abstract":"Stock market forecasting demands models that balance high accuracy with interpretability, particularly when handling highly volatile and uncertain data. This study introduces a novel interpretable forecasting framework that integrates the Fuzzy Time Series (FTS) model with the Linear Fuzzy Information Granule (LFIG) method. The proposed model addresses two major limitations: the inability of conventional FTS models to effectively capture trend dynamics, and the limited capacity of the LFIG method to account for the influence of recent data. The core contributions of this work are threefold: 1) a variable-sized interval partitioning technique optimized via fuzzy C-means clustering and the principle of justifiable granularity, achieving adaptive data segmentation that balances coverage and specificity; 2) a trend extraction mechanism based on LFIG approach, which applies time-dependent linear functions within sliding windows to quantify short-term trends and associated uncertainties; and 3) a fusion of FTS and LFIG outputs via the ordered weighted averaging operator, which emphasizes trend-consistent predictions to enhance forecasting accuracy. Experimental evaluation on five benchmark datasets from Yahoo Finance demonstrates that the proposed model outperforms eight state-of-the-art forecasting methods in terms of predictive performance. Furthermore, it maintains interpretability through transparent fuzzy rules and explicit trend representations, providing a robust and explainable framework for stock market forecasting.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"73722-73734"},"PeriodicalIF":3.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10975817","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896348","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":"Toward Fair Spectrum Sharing: An Enhanced Fixed Waiting Time Model for LAA and Wi-Fi Networks Coexistence","authors":"Moawiah Alhulayil;Miguel López-Benítez;Mohammed Alammar;Abdulrahman Al Ayidh","doi":"10.1109/ACCESS.2025.3564136","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3564136","url":null,"abstract":"This study addresses the challenge of fair spectrum sharing in unlicensed bands for Licensed Assisted Access (LAA) and Wi-Fi coexistence. Existing methods, particularly the 3GPP Category 4 Listen Before Talk (Cat 4 LBT) algorithm, fail to fully meet the fairness criteria due to limitations in dynamic Contention Window (CW) adjustments. To improve spectrum efficiency, we propose an Enhanced Fixed Waiting Time (Enhanced FWT) approach, which leverages a theoretical model of Wi-Fi ON periods to determine fixed waiting times for LAA networks. By employing the <inline-formula> <tex-math>$beta $ </tex-math></inline-formula> distribution to represent Wi-Fi activity more accurately, this model avoids the need for dynamic CW adjustments. Simulation results demonstrate that Enhanced FWT method significantly enhances throughput compared to both the Cat 4 LBT and traditional empirical FWT methods, especially in dense network conditions. This approach, compliant with 3GPP fairness standards, shows promise for robust spectrum sharing, promoting fair LAA/Wi-Fi coexistence in unlicensed bands.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"73735-73744"},"PeriodicalIF":3.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10975751","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143902692","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":"Where the Women Are: Gender Imbalance in Computing and Faculty Perceptions of Theoretical and Applied Research","authors":"Samantha Kleinberg;Jessecae K. Marsh","doi":"10.1109/ACCESS.2025.3564170","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3564170","url":null,"abstract":"Women remain under-represented in academic science, and this is especially true in computing. While there is limited research on gender differences in research focus, there is evidence that women may be more likely to conduct applied research. We surveyed tenured and tenure-track faculty in the United States to understand perceptions of hypothetical researchers who engage in applied or theoretical work. Faculty rated researchers engaged in applied research as less likely to publish their work, receive tenure/be promoted, obtain awards, and get funding for their work. Faculty further rated these researchers as less brilliant, creative, and technically skilled than they rated their theory-focused counterparts. Data from publications, hiring, funding, and awards suggests that applied research may indeed lead to worse career outcomes. We further show that women are more highly represented in applied research areas than theoretical ones. Negative perceptions of applied researchers must now be addressed to avoid exacerbating the gender gap.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"73520-73529"},"PeriodicalIF":3.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10975775","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896555","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 DFT-Based Scheme for PAPR Reduction in SR-OFDM Systems","authors":"Haojia Lv","doi":"10.1109/ACCESS.2025.3564160","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3564160","url":null,"abstract":"This paper focuses on the peak-to-average power ratio (PAPR) reduction in symbol repetition-based orthogonal frequency division multiplexing (SR-OFDM) systems, and a discrete Fourier transform (DFT)-based scheme is proposed to reduce the PAPR of SR-OFDM signals. It is demonstrated that an SR-OFDM system exhibits a larger PAPR than a classical orthogonal frequency division multiplexing (OFDM) system because of the signal superposition of multiple branches, although the cyclic prefix (CP) overhead can be reduced in SR-OFDM systems. Besides, it is shown that the high PAPR is mainly because of the inverse DFT operation at the SR-OFDM transmitter. Therefore, a DFT-based scheme is proposed in this paper to compensate for the inverse DFT operation, without requiring side information or causing signal distortion. To verify the proposed scheme, a theoretical analysis is provided for the signal characteristics, and simulation results of the complementary cumulative distribution function are also given, together with the bit error ratio.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"72930-72937"},"PeriodicalIF":3.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10975283","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896556","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":"5G New Radio for Non-Terrestrial Networks: Analysis and Comparison of HARQ and RLC ARQ Performance Over Satellite Links","authors":"Riccardo Tuninato;Gabriel Maiolini Capez;Nicolò Mazzali;Roberto Garello","doi":"10.1109/ACCESS.2025.3563983","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3563983","url":null,"abstract":"In this paper, we study the extension of 5G New Radio (NR) to Non-Terrestrial Networks (NTN). For terrestrial ones, Hybrid Automatic Repeat reQuest (HARQ) is the main retransmission solution used by 5G NR at the physical and MAC layers, enhancing decoding performance through diversity and coding gain. However, for NTN, its implementation faces challenges due to the significant delays caused by the long distances of satellites. In the first part, we begin by investigating the minimum number of HARQ processes required for various LEO scenarios, as well as the relationship between the number of processes and the coherence time of the satellite link. Next, while the performance of 5G retransmission schemes over AWGN and terrestrial channels is well explored, this is not the case for realistic satellite channel models. To address this, we have developed an open-source simulator that accurately implements all the blocks of the data channel transmission and reception chain, including the retransmission schemes and the Land Mobile Satellite (LMS) channel. We consider the 5G NR Physical Downlink Shared Channel (PDSCH) and we present and discuss a number of results over the LMS channel, which are important to understand the HARQ performance for the NTN satellite scenario. In the second part, we consider the 5G NR alternative retransmission solution, RLC ARQ, which is available at the Radio Link Control (RLC) layer. This method might be interesting for satellite links, because it adds minimal complexity to the receiver side, but it provides less enhancement to signal reception capabilities and more latency. We first present an analytic model to compute its performance over the LMS channel, then we analyze its behavior. Finally, we provide a detailed comparison and discussion of HARQ and RLC ARQ performance in terms of block error rate, spectral efficiency, and latency. This extensive analysis provides valuable insights for researchers and space agencies interested in applying 5G NR to satellite-based Non-Terrestrial Networks.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"75396-75411"},"PeriodicalIF":3.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10975810","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143902725","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":"Optimized Scheduling of Integrated Energy Systems Considering Electric Vehicles and Carbon Emission Trading","authors":"Yanhong Xiao;Bin Qian;Jiaxiang Ou;Weibin Lin;Houpeng Hu;Xiaoming Lin;Yuedan Deng;Jianlin Tang","doi":"10.1109/ACCESS.2025.3563994","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3563994","url":null,"abstract":"This study proposes an optimized dispatch model for integrated energy systems (IES) incorporating electric vehicles (EVs) and carbon emission trading (CET) to analyze their dynamic interactions. The model aims to minimize IES operating costs by systematically evaluating the impacts of EV penetration levels and CET parameters on economic and environmental performance. Methodologically, Monte Carlo simulations characterize stochastic EV behaviors, a stepwise CET mechanism is developed with emission thresholds, and piecewise linearization combined with convex relaxation transforms nonlinear constraints into tractable formulations. The YALMIP/GUROBI solver is employed to compare eight dispatch scenarios. Key results demonstrate that integrating EVs with carbon capture under CET reduces operating costs by 7.64% and emissions by 17.68%. System emissions exhibit a U-shaped relationship with EV penetration, reaching a minimum at 9.20%. Maximum emission reductions from EV charging optimization occur when CET prices range 250-300 CNY/ton and EV penetration spans 12.31%-19.43%, providing critical thresholds for policy design.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"74147-74162"},"PeriodicalIF":3.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10975782","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143902712","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":"Density Peaks Clustering Algorithm Based on Neighborhood Radius and Membership Degree","authors":"Fuxiang Li;Tingting Jiang;Jia Wei;Shu Li;Yunxiao Shan","doi":"10.1109/ACCESS.2025.3563990","DOIUrl":"https://doi.org/10.1109/ACCESS.2025.3563990","url":null,"abstract":"The density peaks clustering (DPC) algorithm is a density-based clustering method that effectively identifies clusters with uniform densities. However, if the datasets have uneven density, clusters with lower densities tend to have lower decision values, which often leads to the cluster centers being overlooked. To address this limitation, a novel density peaks clustering algorithm incorporating neighborhood radius and membership degree is proposed. The method begins by introducing k-nearest neighbor density estimation to establish a density threshold, segmenting datasets into high-density and low-density regions. In the high-density region, the DPC algorithm is applied to perform initial clustering, identifying prominent cluster structures. For low-density points, neighborhood radius and density criteria are employed to assign these points to appropriate high-density clusters, thereby reducing misclassification. In addition, the membership degree concept is incorporated to improve the accuracy of low-density point assignments. Low-density points that remain unassigned undergo secondary clustering using the DPC algorithm. The proposed approach is evaluated on eight synthetic datasets and eleven real-world datasets, with comparisons to DPC-KNN, DPC, K-means, and DBSCAN. The experimental results demonstrate that the proposed algorithm consistently outperforms these methods in clustering performance, highlighting its effectiveness and robustness.","PeriodicalId":13079,"journal":{"name":"IEEE Access","volume":"13 ","pages":"72329-72346"},"PeriodicalIF":3.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10975780","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896256","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}