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17 pages, 1943 KB  
Article
Hearing Aid Amplification Schemes Adjusted to Tinnitus Pitch: A Randomized Controlled Trial
by Jose L. Santacruz, Emile de Kleine and Pim van Dijk
Audiol. Res. 2025, 15(6), 143; https://doi.org/10.3390/audiolres15060143 - 22 Oct 2025
Viewed by 385
Abstract
Background/Objectives: Hearing aids can be used as a treatment for tinnitus. There are indications that this treatment is most effective when the tinnitus pitch falls in the frequency range of amplification of the hearing aid. Then, the hearing aid provides masking of [...] Read more.
Background/Objectives: Hearing aids can be used as a treatment for tinnitus. There are indications that this treatment is most effective when the tinnitus pitch falls in the frequency range of amplification of the hearing aid. Then, the hearing aid provides masking of the tinnitus. Alternatively, it has been suggested that a gap in the amplification around the tinnitus pitch would engage lateral inhibition and thereby reduce the tinnitus. Methods: To test these ideas, we conducted a randomized controlled trial. Patients were fitted with hearing aids using three different amplification schemes: (1) standard amplification according to the NAL-NL2 prescription procedure, (2) boosted amplification at the tinnitus frequency to enhance tinnitus masking, and (3) notch-filtered amplification at the tinnitus frequency to engage lateral inhibition and suppress tinnitus. The goal was to compare the boosted and notched amplification schemes to standard amplification. The primary outcome measure was tinnitus handicap as measured by the Tinnitus Functional Index (TFI). The trial was designed as a double-blind Latin square balanced crossover study. Eighteen tinnitus patients with moderate hearing loss were included. All of them were experienced hearing aid users. After two weeks of initial adaptation to the new hearing aids with standard settings, each setting was tried for four weeks. Results: There was an average reduction of 6.9 points on the TFI score after the adaptation phase, possibly due to a placebo effect. The TFI score did not differ significantly from the standard setting after using the notched or the boosted settings. Although notched amplification performed better than boosted amplification, this difference did not reach the clinical significance level. Regardless of the TFI outcomes, most participants had an individual preference for a particular setting. This preference was approximately uniformly distributed across the three amplification schemes. Conclusions: Notch-filtered and boosted amplification did not provide better tinnitus suppression than standard amplification. The individual preferences highlighted the importance of tailor-made approaches to hearing aid amplification in clinical practice. Further studies should explore the differences among patient’s tinnitus and their preference for a hearing aid setting. Full article
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15 pages, 1192 KB  
Article
Development of the Medial Longitudinal Arch of the Foot in Czech Pre- and Primary School Children—A Cross-Sectional and Longitudinal Approach
by Jakub Novák, Jan Novák, Anna Vážná and Petr Sedlak
Children 2025, 12(10), 1407; https://doi.org/10.3390/children12101407 - 17 Oct 2025
Viewed by 236
Abstract
Background/Objectives: The medial longitudinal arch (MLA) is initially masked by a fat pad that makes the foot appear flat. In preschool age, this fat pad resorbs, and the arch becomes more defined. The exact age at which the arch attains its final [...] Read more.
Background/Objectives: The medial longitudinal arch (MLA) is initially masked by a fat pad that makes the foot appear flat. In preschool age, this fat pad resorbs, and the arch becomes more defined. The exact age at which the arch attains its final form remains uncertain due to high inter-individual variability and differing assessment methods, which complicates the distinction between physiological development and potential abnormalities. Moreover, commonly used classification terms such as “flat” or “normal” do not adequately reflect the developmental progression and may be misleading in young children. This study aimed to describe the MLA developmental patterns and propose an adjusted classification terminology to improve clinical differentiation between feet undergoing normal developmental changes and cases requiring intervention. Methods: The present study employs both cross-sectional (285 children aged 4.00–8.99 years) and longitudinal (50 children measured annually between ages 4–6) designs. Foot dimensions were assessed using standard anthropometry, and the MLA was assessed via podograms using the Chippaux–Smirak index (CSI). To better reflect the developmental nature of the MLA, the arch was categorized as “formed” and “unformed”. Cross-sectional data were analyzed with ANOVA and visualized using LOESS regression, longitudinal data with linear mixed models, and relationships between CSI and foot dimensions with Spearman’s correlation. Results: MLA development showed significant changes up to age 6, with the most pronounced changes occurring between ages 4 and 5 and slowing thereafter. Children with an unformed arch at age 4 exhibited a steeper developmental trajectory than those with an already advanced arch form. Correlations between arch shape and foot dimensions were statistically significant but weak. No significant between-sex differences were observed. Conclusions: The timing of the most pronounced phase of medial longitudinal arch (MLA) development varies between individuals and is typically completed by 6 years of age, with no sex-dependent differences. Age 6 therefore represents a practical milestone for reliable clinical assessment, since earlier classifications risk misinterpreting normal developmental variation as pathology. Full article
(This article belongs to the Section Pediatric Orthopedics & Sports Medicine)
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58 pages, 3300 KB  
Review
Roadmap for Exoplanet High-Contrast Imaging: Nulling Interferometry, Coronagraph, and Extreme Adaptive Optics
by Ziming Guo, Qichang An, Canyu Yang, Jincai Hu, Xin Li and Liang Wang
Photonics 2025, 12(10), 1030; https://doi.org/10.3390/photonics12101030 - 17 Oct 2025
Viewed by 490
Abstract
The detection and characterization of exoplanets are central topics in astronomy, and high-contrast imaging techniques such nulling interferometry, coronagraphs, and extreme adaptive optics (ExAO) are key tools for the direct detection of exoplanets. This review synthesizes the pivotal role of these techniques in [...] Read more.
The detection and characterization of exoplanets are central topics in astronomy, and high-contrast imaging techniques such nulling interferometry, coronagraphs, and extreme adaptive optics (ExAO) are key tools for the direct detection of exoplanets. This review synthesizes the pivotal role of these techniques in astronomical research and critically analyzes their role as key drivers of progress in the field. Nulling interferometry suppresses stellar light through the phase control of multiple telescopes, thereby enhancing the detection of faint planetary signals. This technology has evolved from the initial Bracewell concept to the LIFE (Large Interferometer For Exoplanets) technique, which will achieve a contrast ratio of 10−7 in the mid-infrared wavelength range in the future. Coronagraphs block starlight to create a “dark region” for direct observation of exoplanets. By leveraging innovative mask designs, theoretical contrast ratios of up to 4 × 10−9 can be achieved. ExAO systems achieve precise wavefront correction to optimize the high-contrast imaging performance and mitigate atmospheric disturbances. By leveraging wavefront sensing, thousand-element deformable mirrors, and real-time control algorithms, these systems suppress the turbulence correction residuals to 80 nm RMS, enabling ground-based telescopes to achieve a Strehl ratio exceeding 0.9. This work provides a comprehensive analysis of the underlying principles, prevailing challenges, and future application prospects of these technologies in astronomy. Full article
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27 pages, 7948 KB  
Article
Attention-Driven Time-Domain Convolutional Network for Source Separation of Vocal and Accompaniment
by Zhili Zhao, Min Luo, Xiaoman Qiao, Changheng Shao and Rencheng Sun
Electronics 2025, 14(20), 3982; https://doi.org/10.3390/electronics14203982 - 11 Oct 2025
Viewed by 416
Abstract
Time-domain signal models have been widely applied to single-channel music source separation tasks due to their ability to overcome the limitations of fixed spectral representations and phase information loss. However, the high acoustic similarity and synchronous temporal evolution between vocals and accompaniment make [...] Read more.
Time-domain signal models have been widely applied to single-channel music source separation tasks due to their ability to overcome the limitations of fixed spectral representations and phase information loss. However, the high acoustic similarity and synchronous temporal evolution between vocals and accompaniment make accurate separation challenging for existing time-domain models. These challenges are mainly reflected in two aspects: (1) the lack of a dynamic mechanism to evaluate the contribution of each source during feature fusion, and (2) difficulty in capturing fine-grained temporal details, often resulting in local artifacts in the output. To address these issues, we propose an attention-driven time-domain convolutional network for vocal and accompaniment source separation. Specifically, we design an embedding attention module to perform adaptive source weighting, enabling the network to emphasize components more relevant to the target mask during training. In addition, an efficient convolutional block attention module is developed to enhance local feature extraction. This module integrates an efficient channel attention mechanism based on one-dimensional convolution while preserving spatial attention, thereby improving the ability to learn discriminative features from the target audio. Comprehensive evaluations on public music datasets demonstrate the effectiveness of the proposed model and its significant improvements over existing approaches. Full article
(This article belongs to the Section Artificial Intelligence)
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23 pages, 5736 KB  
Article
Novel Imaging Devices: Coding Masks and Varifocal Systems
by Cristina M. Gómez-Sarabia and Jorge Ojeda-Castañeda
Appl. Sci. 2025, 15(19), 10743; https://doi.org/10.3390/app151910743 - 6 Oct 2025
Viewed by 335
Abstract
To design novel imaging devices, we use masks coded with numerical sequences. These masks work in conjunction with varifocal systems that implement zero-throw tunable magnification. Some masks control field depth, even when the size of the pupil aperture remains fixed. Pairs of vortex [...] Read more.
To design novel imaging devices, we use masks coded with numerical sequences. These masks work in conjunction with varifocal systems that implement zero-throw tunable magnification. Some masks control field depth, even when the size of the pupil aperture remains fixed. Pairs of vortex masks are used to implement tunable phase radial profiles, like axicons and lenses. The autocorrelation properties of the Barker sequences are applied to the generation of narrow passband windows on the OTF. For this application, we apply Barker matrices in rectangular coordinates. A similar procedure, but now in polar coordinates, is useful for sensing in-plane rotations. We implement geometrical transformations by using zero-throw, tunable, anamorphic magnifications. Full article
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27 pages, 25256 KB  
Article
A Progressive Target-Aware Network for Drone-Based Person Detection Using RGB-T Images
by Zhipeng He, Boya Zhao, Yuanfeng Wu, Yuyang Jiang and Qingzhan Zhao
Remote Sens. 2025, 17(19), 3361; https://doi.org/10.3390/rs17193361 - 4 Oct 2025
Viewed by 575
Abstract
Drone-based target detection using visible and thermal (RGB-T) images is critical in disaster rescue, intelligent transportation, and wildlife monitoring. However, persons typically occupy fewer pixels and exhibit more varied postures than vehicles or large animals, making them difficult to detect in unmanned aerial [...] Read more.
Drone-based target detection using visible and thermal (RGB-T) images is critical in disaster rescue, intelligent transportation, and wildlife monitoring. However, persons typically occupy fewer pixels and exhibit more varied postures than vehicles or large animals, making them difficult to detect in unmanned aerial vehicle (UAV) remote sensing images with complex backgrounds. We propose a novel progressive target-aware network (PTANet) for person detection using RGB-T images. A global adaptive feature fusion module (GAFFM) is designed to fuse the texture and thermal features of persons. A progressive focusing strategy is used. Specifically, we incorporate a person segmentation auxiliary branch (PSAB) during training to enhance target discrimination, while a cross-modality background mask (CMBM) is applied in the inference phase to suppress irrelevant background regions. Extensive experiments demonstrate that the proposed PTANet achieves high accuracy and generalization performance, reaching 79.5%, 47.8%, and 97.3% mean average precision (mAP)@50 on three drone-based person detection benchmarks (VTUAV-det, RGBTDronePerson, and VTSaR), with only 4.72 M parameters. PTANet deployed on an embedded edge device with TensorRT acceleration and quantization achieves an inference speed of 11.177 ms (640 × 640 pixels), indicating its promising potential for real-time onboard person detection. The source code is publicly available on GitHub. Full article
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16 pages, 4249 KB  
Article
Defining Robust NVH Requirements for an Electrified Powertrain Mounting System Based on Solution Space During Early Phase of Development
by José G. Cóndor López, Karsten Finger and Sven Herold
Appl. Sci. 2025, 15(18), 10241; https://doi.org/10.3390/app151810241 - 20 Sep 2025
Viewed by 427
Abstract
Electrification introduces additional NVH (noise, vibration and harshness) challenges during the development of powertrain mounting systems due to high-frequency excitations from the powertrain and the absence of masking effects from the combustion engine. In these frequency ranges, engine mounts can stiffen up to [...] Read more.
Electrification introduces additional NVH (noise, vibration and harshness) challenges during the development of powertrain mounting systems due to high-frequency excitations from the powertrain and the absence of masking effects from the combustion engine. In these frequency ranges, engine mounts can stiffen up to a factor of five due to continuum resonances, reducing their structure-borne sound isolation properties and negatively impacting the customer’s NVH perception. Common hardening factors used during elastomer mount development are therefore limited in terms of their applicable validation frequency range. This study presents a methodology for determining decoupled permissible stiffness ranges for a double-isolated mounting system up to 1500 Hz, based on solution space engineering. Instead of optimizing for a single best design, we seek to maximize solution boxes, resulting in robust stiffness ranges that ensure the fulfillment of the formulated system requirements. These ranges serve as NVH requirements at the component level, derived from the sound pressure level at the seat location. They provide tailored guidelines for mount development, such as geometric design or optimal resonance placement, while simultaneously offering maximum flexibility by spanning the solution space. The integration of machine learning approaches enables the application of large-scale finite-element models within the framework of solution space analysis by reducing the computational time by a factor of 7.19·103. From a design process standpoint, this facilitates frontloading by accelerating the evaluation phase as suppliers can directly benchmark their mounting concepts against the permissible ranges and immediately verify compliance with the defined targets. Full article
(This article belongs to the Special Issue Advances in Dynamic Systems by Smart Structures)
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15 pages, 5395 KB  
Article
Recommendations for Preventing Free-Stroke Failures in Electric Vehicle Suspension Dampers Based on Experimental and Numerical Approaches
by Na Zhang, Zhenhuan Yu and Zhiyuan Liu
World Electr. Veh. J. 2025, 16(7), 392; https://doi.org/10.3390/wevj16070392 - 13 Jul 2025
Viewed by 480
Abstract
Free stroke, which means the intermittent no-load operation state of dampers, can cause an abnormal noise and unavoidably lead to the deterioration of vehicle NVH performance. In electric vehicles, the noise is particularly intolerable because there are no engine sounds to mask it. [...] Read more.
Free stroke, which means the intermittent no-load operation state of dampers, can cause an abnormal noise and unavoidably lead to the deterioration of vehicle NVH performance. In electric vehicles, the noise is particularly intolerable because there are no engine sounds to mask it. Focusing on this, the mechanism of the free-stroke phenomenon is analyzed. A method, which involves parametric models and numerical simulation, is proposed to prevent free-stroke phenomena during the damper design phase. This paper proposes a free-stroke mechanism based on a fluid–structure interaction (FSI) numerical method, combined with experiments, which intends to provide a design reference with guaranteed performance for dampers. Initially, according to parametric cavitation models and by applying numerical methods, simulations for the proposed FSI model are calculated. By analyzing the simulation results, strain variation characteristics near the bottom of the damper valves are revealed, which establish the relationships between strain change, cavitation and the free-stroke phenomena. Meanwhile, the specific position and distribution of free-stroke failure are clearly located by running diverse loading speeds. Finally, all the theoretical analysis results are verified using damper noise tests and indicator bench tests. Full article
(This article belongs to the Special Issue Intelligent Electric Vehicle Control, Testing and Evaluation)
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19 pages, 1886 KB  
Article
Uncertainty-Guided Prediction Horizon of Phase-Resolved Ocean Wave Forecasting Under Data Sparsity: Experimental and Numerical Evaluation
by Yuksel Rudy Alkarem, Kimberly Huguenard, Richard W. Kimball and Stephan T. Grilli
J. Mar. Sci. Eng. 2025, 13(7), 1250; https://doi.org/10.3390/jmse13071250 - 28 Jun 2025
Viewed by 622
Abstract
Accurate short-term wave forecasting is critical for the safe and efficient operation of marine structures that rely on real-time, phase-resolved ocean wave information for control and monitoring purposes (e.g., digital twins). These systems often depend on environmental sensors (e.g., waverider buoys, wave-sensing LIDAR). [...] Read more.
Accurate short-term wave forecasting is critical for the safe and efficient operation of marine structures that rely on real-time, phase-resolved ocean wave information for control and monitoring purposes (e.g., digital twins). These systems often depend on environmental sensors (e.g., waverider buoys, wave-sensing LIDAR). Challenges arise when upstream sensor data are missing, sparse, or phase-shifted due to drift. This study investigates the performance of two machine learning models, time-series dense encoder (TiDE) and long short-term memory (LSTM), for forecasting phase-resolved ocean surface elevations under varying degrees of data degradation. We introduce the τ-trimming algorithm, which adapts the prediction horizon based on uncertainty thresholds derived from historical forecasts. Numerical wave tank (NWT) and wave basin experiments are used to benchmark model performance under short- and long-term data masking, spatially coarse sensor grids, and upstream phase shifts. Results show under a 50% probability of upstream data loss, the τ-trimmed TiDE model achieves a 46% reduction in error at the most upstream target, compared to 22% for LSTM. Furthermore, phase misalignment in upstream data introduces a near-linear increase in forecast error. Under moderate model settings, a ±3 s misalignment increases the mean absolute error by approximately 0.5 m, while the same error is accumulated at ±4 s using the more conservative approach. These findings inform the design of resilient, uncertainty-aware wave forecasting systems suited for realistic offshore sensing environments. Full article
(This article belongs to the Special Issue Data-Driven Methods for Marine Structures)
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16 pages, 2271 KB  
Article
Foucault–Barker Mask: Nonconventional Schlieren Technique
by Cristina M. Gómez-Sarabia and Jorge Ojeda-Castañeda
Optics 2025, 6(2), 23; https://doi.org/10.3390/opt6020023 - 4 Jun 2025
Viewed by 704
Abstract
We present a theoretical framework for designing optical masks, which are useful for implementing nonconventional Schlieren techniques. We revisit the use of effective transfer functions, which emphasize the role of symmetries in the design of coded masks. The proposed technique implements an optical [...] Read more.
We present a theoretical framework for designing optical masks, which are useful for implementing nonconventional Schlieren techniques. We revisit the use of effective transfer functions, which emphasize the role of symmetries in the design of coded masks. The proposed technique implements an optical autocorrelation of a mask, which is coded with the Barker sequences. For the same purpose, one can also use masks coded with the pseudorandom sequences. For the sake of completeness, we link our deterministic theoretical framework with a simple statistical model. The proposed technique may be useful for the automatic sensing of phase gradients. Full article
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15 pages, 243 KB  
Article
Adaptation to Long-Term Home Non-Invasive Ventilation for People with Chronic Hypercapnic Respiratory Failure: A Qualitative Study
by Nur Zahrah Yuko Yacob Hussain, Norasyikin Hassan, Hang Siang Wong, Yingjuan Mok and Piyanee Klainin-Yobas
Nurs. Rep. 2025, 15(5), 176; https://doi.org/10.3390/nursrep15050176 - 20 May 2025
Viewed by 1116
Abstract
Background/Objectives: Home non-invasive ventilation use is the primary treatment for improving respiratory function in people with chronic hypercapnic respiratory failure. Non-invasive ventilation has also been studied to understand users’ perspectives. However, no studies have been conducted on how users adapt to non-invasive ventilation [...] Read more.
Background/Objectives: Home non-invasive ventilation use is the primary treatment for improving respiratory function in people with chronic hypercapnic respiratory failure. Non-invasive ventilation has also been studied to understand users’ perspectives. However, no studies have been conducted on how users adapt to non-invasive ventilation in their homes from the early phase of their diagnosis as a long-term utility. Methods: The study employed a descriptive qualitative design guided by Roy’s adaptation model. A purposive sample was used. People with chronic hypercapnic respiratory failure who had used NIV at home for a minimum of six months would be eligible. They were interviewed at a sleep and assisted ventilation centre. Their interviews were audio recorded before proceeding with transcription. Each transcript was thematically analysed. Results: Twenty participants were included in the study, from which six themes emerged. They experienced a common transition, from denying the need for non-invasive ventilation to integrating them into their daily lives at home. Throughout this process, they had emotional turmoil, faced difficulties in keeping their masks on, and improved sleep quality. They also adjusted their social interactions before fully accepting the use of non-invasive ventilation. Their coping strategies in their role functions at home and social interaction were also narrated. Their family members were pivotal in their adaptation period. Conclusions: Gaining insight into individuals’ adaptation experiences can facilitate early identification of potential challenges faced by new users of non-invasive ventilation. This study calls for healthcare professionals to assess users’ understanding of long-term commitment and their living conditions early for a successful NIV adaptation. Full article
(This article belongs to the Section Nursing Care for Older People)
16 pages, 3751 KB  
Article
Improved Face Image Super-Resolution Model Based on Generative Adversarial Network
by Qingyu Liu, Yeguo Sun, Lei Chen and Lei Liu
J. Imaging 2025, 11(5), 163; https://doi.org/10.3390/jimaging11050163 - 19 May 2025
Cited by 1 | Viewed by 1841
Abstract
Image super-resolution (SR) models based on the generative adversarial network (GAN) face challenges such as unnatural facial detail restoration and local blurring. This paper proposes an improved GAN-based model to address these issues. First, a Multi-scale Hybrid Attention Residual Block (MHARB) is designed, [...] Read more.
Image super-resolution (SR) models based on the generative adversarial network (GAN) face challenges such as unnatural facial detail restoration and local blurring. This paper proposes an improved GAN-based model to address these issues. First, a Multi-scale Hybrid Attention Residual Block (MHARB) is designed, which dynamically enhances feature representation in critical face regions through dual-branch convolution and channel-spatial attention. Second, an Edge-guided Enhancement Block (EEB) is introduced, generating adaptive detail residuals by combining edge masks and channel attention to accurately recover high-frequency textures. Furthermore, a multi-scale discriminator with a weighted sub-discriminator loss is developed to balance global structural and local detail generation quality. Additionally, a phase-wise training strategy with dynamic adjustment of learning rate (Lr) and loss function weights is implemented to improve the realism of super-resolved face images. Experiments on the CelebA-HQ dataset demonstrate that the proposed model achieves a PSNR of 23.35 dB, a SSIM of 0.7424, and a LPIPS of 24.86, outperforming classical models and delivering superior visual quality in high-frequency regions. Notably, this model also surpasses the SwinIR model (PSNR: 23.28 dB → 23.35 dB, SSIM: 0.7340 → 0.7424, and LPIPS: 30.48 → 24.86), validating the effectiveness of the improved model and the training strategy in preserving facial details. Full article
(This article belongs to the Section AI in Imaging)
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29 pages, 2036 KB  
Article
Attention-Based Multi-Objective Control for Morphing Aircraft
by Qien Fu and Changyin Sun
Biomimetics 2025, 10(5), 280; https://doi.org/10.3390/biomimetics10050280 - 30 Apr 2025
Cited by 1 | Viewed by 807
Abstract
This paper proposes a learning-based joint morphing and flight control framework for avian-inspired morphing aircraft. Firstly, a novel multi-objective multi-phase optimal control problem is formulated to synthesize the comprehensive flight missions, incorporating additional requirements such as fuel consumption, maneuverability, and agility of the [...] Read more.
This paper proposes a learning-based joint morphing and flight control framework for avian-inspired morphing aircraft. Firstly, a novel multi-objective multi-phase optimal control problem is formulated to synthesize the comprehensive flight missions, incorporating additional requirements such as fuel consumption, maneuverability, and agility of the morphing aircraft. Subsequently, an auxiliary problem, employing ϵ-constraint and augmented state methods, is introduced to yield a finite and locally Lipschitz continuous value function, which facilitates the construction of a neural network controller. Furthermore, a multi-phase pseudospectral method is derived to discretize the auxiliary problem and formulate the corresponding nonlinear programming problem, where open loop optimal solutions of the multi-task flight mission are generated. Finally, a learning-based feedback controller is established using data from the open loop solutions, where a temporal masked attention mechanism is developed to extract information from sequential data more efficiently. Simulation results demonstrate that the designed attention module in the learning scheme yields a significant 53.5% reduction in test loss compared to the baseline model. Additionally, the proposed learning-based joint morphing and flight controller achieves a 37.6% improvement in average tracking performance over the fixed wing configuration, while also satisfying performance requirements for fuel consumption, maneuverability, and agility. Full article
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32 pages, 2964 KB  
Article
Enhancement of Optical Wireless Discrete Multitone Channel Capacity Based on Li-Fi Using Sparse Coded Mask Modeling
by Yong-Yuk Won, Heetae Han, Dongmin Choi and Sang Min Yoon
Photonics 2025, 12(4), 395; https://doi.org/10.3390/photonics12040395 - 18 Apr 2025
Viewed by 581
Abstract
A sparse coded mask modeling technique is proposed to increase the transmission capacity of an optical wireless link based on Li-Fi. The learning model for the discrete multitone (DMT) signal waveform is implemented using the proposed technique, which is designed based on a [...] Read more.
A sparse coded mask modeling technique is proposed to increase the transmission capacity of an optical wireless link based on Li-Fi. The learning model for the discrete multitone (DMT) signal waveform is implemented using the proposed technique, which is designed based on a masked auto-encoder. The entire length of the DMT signal waveform, encoded using quadrature phase shift keying (QPSK) or 16-quadrature amplitude modulation (16-QAM) symbols, is divided into equal intervals to generate DMT patches, which are subsequently compressed based on the specified masking ratio. After 1-m optical wireless transmission, the DMT signal waveform is reconstructed from the received DMT patch through a decoding process and then QPSK or 16-QAM symbols are recovered. Using the proposed technique, we demonstrate that we can increase the transmission capacity by up to 1.85 times for a 10 MHz physical bandwidth. Additionally, we verify that the proposed technique is feasible in Li-Fi networks with illumination environments above 240 lux. Full article
(This article belongs to the Special Issue Optical Signal Processing for Advanced Communication Systems)
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15 pages, 1708 KB  
Article
ET-Mamba: A Mamba Model for Encrypted Traffic Classification
by Jian Xu, Liangbing Chen, Wenqian Xu, Longxuan Dai, Chenxi Wang and Lei Hu
Information 2025, 16(4), 314; https://doi.org/10.3390/info16040314 - 16 Apr 2025
Cited by 1 | Viewed by 1544
Abstract
With the widespread use of encryption protocols on network data, fast and effective encryption traffic classification can improve the efficiency of traffic analysis. A resampling method combining Wasserstein GAN and random selection is proposed for solving the dataset imbalance problem, and it uses [...] Read more.
With the widespread use of encryption protocols on network data, fast and effective encryption traffic classification can improve the efficiency of traffic analysis. A resampling method combining Wasserstein GAN and random selection is proposed for solving the dataset imbalance problem, and it uses Wasserstein GAN for oversampling and random selection for undersampling to achieve class equalization. Based on Mamba, an ultra-low parametric quantity model, we propose an encrypted traffic classification model, ET-Mamba, which has a pre-training phase and a fine-tuning phase. During the pre-training phase, positional embedding is used to characterize the blocks of the traffic grayscale image, and random masking is used to strengthen the learning of the intrinsic correlation among the blocks of the traffic grayscale image. During the fine-tuning phase, the agent attention mechanism is adopted in the feature extraction phase to achieve global information modeling at a low computational cost, and the SmoothLoss function is designed to solve the problem of the insufficient generalization ability of cross-entropy loss function during training. The experimental results show that the proposed model significantly reduces the number of parameters and outperforms other models in terms of classification accuracy on non-VPN datasets. Full article
(This article belongs to the Special Issue Machine Learning and Data Mining for User Classification)
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