Search Results (935)

Continuous monitoring of pig behavior is essential for timely health management and welfare assessment in commercial production systems. Although vision-based methods have been widely studied, their practical application in commercial barns is often limited by variable lighting, frequent occlusion, and high stocking density. Acoustic sensing offers a non-contact alternative that is independent of lighting conditions; however, reliable behavior classification from pig vocalizations remains challenging in commercial environments because of background noise and temporal variability in sound patterns. In this study, an attention-guided acoustic framework, termed ATF-Conformer, was developed for pig vocalization classification under farm conditions. A five-class vocalization dataset was collected from finishing Landrace pigs and multiparous sows on a commercial farm, including cough, scream, estrus, feeding, and normal behavior sounds. The proposed framework combined spectrogram denoising with interactive attention to enhance behavior-related acoustic information, while a time-frequency-decoupled Conformer encoder was introduced to improve feature representation under noisy conditions. Final classification was performed using mask-based temporal pooling with an additive angular margin Softmax objective. In five-fold grouped cross-validation, ATF-Conformer achieved an accuracy of 97.34% ± 0.42 and outperformed several existing acoustic models across multiple evaluation metrics. A similar accuracy of 97.38% was obtained on an independent test set, indicating stable performance across datasets. These results suggest that the proposed method can support continuous, non-invasive pig vocalization-based behavior monitoring and may assist farm owners or workers in pen-level screening of frequent cough or abnormal vocal events, thereby supporting targeted on-site inspection in precision livestock farming. Full article

In historic districts, the audiovisual environment plays an important role in shaping both cultural expression and spatial experience. However, the influence of acoustic and visual environmental factors on perceived street vitality remains insufficiently understood. Taking the Shangxiahang Historic District in Fuzhou as a case study, this paper employs on-site sound pressure level measurements, panoramic visual data collection, questionnaire surveys, principal component analysis, correlation analysis, and multiple regression analysis to systematically examine the effects of acoustic and visual environmental factors on perceived street vitality. The results indicate that traditional cultural sounds and natural sounds have a significant positive impact on perceived street vitality, while construction noise and tour guide’s horn sound exhibit negative effects. Regarding the visual environment, street and alley spaces, traditional architecture, greenery, and the sky are all important factors in promoting perceived street vitality. Further regression analysis reveals that the perception rate of street and alley spaces has the strongest influence, followed by the perception rate of traditional architecture, the perceived frequency of folk activity sounds, preference for greenery, and the perception rate of the sky. These findings demonstrate that perceived street vitality in historic districts does not depend on a single environmental factor but rather arises from synergistic interaction between culturally meaningful acoustic cues and legible spatial forms. These results offer practical implications for multisensory design and vitality-oriented regeneration in historic districts. Full article

With the increasing demand for intelligent fault monitoring, acoustic-based diagnosis has emerged as a promising solution for industrial applications such as pipeline leakage and electrical equipment fault detection. However, complex working conditions and domain shifts significantly degrade model performance, especially when unseen target domain data is unavailable. To address this, we propose an amplitude-phase collaborative augmentation network named AP-CANet tailored for acoustic fault diagnosis. Specifically, the network adaptively aligns amplitude and phase features across multiple source domains and performs label-consistent sample augmentation to enrich data diversity while preserving semantic consistency. A frequency–spatial interaction module further integrates global spectral information with local temporal details to improve feature discriminability. Moreover, we introduce a manifold triplet loss that scales shortest path distances in the feature manifold, encouraging the model to better capture subtle distinctions among hard samples and improving intra-class compactness and inter-class separability. We evaluate the proposed method on two publicly available datasets: the Pipeline Leak Acoustic Dataset (GPLA-12) and the Electrical Sound Dataset (MIMII-DG). Experimental results demonstrate superior performance under domain-shift scenarios, highlighting the method’s potential for scalable and low-cost acoustic fault diagnosis in real-world industrial environments. Full article

Unlike reactive systems, mechanical ventilation controlled by CO₂ concentration operates at a target efficiency that dynamically increases whenever the target CO₂ level is exceeded. This approach eliminates the typical ‘dead-time’ and prevents air quality degradation by ensuring the system adjusts its performance immediately in response to concentration changes. In this work, the study focuses on the development and evaluation of data-driven predictive models for near-term indoor CO₂ forecasting that can be integrated into pre-occupancy ventilation strategies, rather than designing a complete control scheme. Experimental data were collected over four months in a 48 m² smart laboratory configured as an open-plan office, where a heterogeneous IoT sensing architecture logged synchronized time-series measurements of CO₂ and microclimate variables (temperature, relative humidity, PM_2.5, TVOCs), together with acoustic noise levels and appliance-level energy consumption used as indirect occupancy-related signals. Raw telemetry was transformed into a 22-feature state vector using a structured feature engineering method incorporating z-score standardization, cyclic time encodings, multi-horizon CO₂ lags, rolling statistics, momentum features, and non-linear interactions to represent temporal autocorrelation and daily periodicity. The study benchmarks multiple regression paradigms, including simple baselines and ensemble methods, and found that an automated multi-level stacked ensemble achieved the highest predictive fidelity for short-term forecasting, with an Mean Absolute Error (MAE) of 32.97 ppm across an observed CO₂ range of 403–2305 ppm, representing improvements of approximately 24% and 43% over Linear Regression and K-Nearest Neighbors (KNN), respectively. Temporal diagnostics showed strong phase alignment with observed CO₂ rises during occupancy transitions and statistically reliable prediction intervals. Five-fold walk-forward cross-validation confirmed the temporal stability of these results, with top models achieving consistent R² values of 0.93–0.95 across Folds 2–5. These results demonstrate that, within a single-room university laboratory setting, historical sensor data from low-cost IoT devices can support accurate short-term CO₂ forecasting, providing a predictive layer that could support future proactive ventilation scheduling aimed at reducing CO₂ lag at the start of occupancy while avoiding unnecessary ventilation runtime. Generalization to other building types and occupancy profiles requires further validation. Full article

Background: Dyslexia is a reading disorder that is associated with phonological processing and awareness difficulties. However, little is known about phonetic production in dyslexia. Whereas individual differences in speech sound perception were linked to native and foreign speech sound production in typical readers, this remains to be explored in dyslexia. Given the phonetic processing deficits frequently encountered in dyslexia, we aimed to pinpoint potential differences in the acoustic realization of native phonemic production in adults with dyslexia. Methods: Ten adults with dyslexia and ten age-matched typical readers produced 24 native-language minimal voiced–voiceless word pairs across three places of articulation (labial, dental, velar) in a reading task. Acoustic analyses addressed phonemic category size, between-category distance, and voice onset time (VOT). Pseudoword reading performance served as an index of phonological decoding ability. Results: For category size, we observed a trend-level group-by-type interaction (p = 0.059, η² = 0.04): both groups showed larger category sizes for voiced than voiceless consonants, but this difference was numerically larger in typical readers. Between-category distance showed a marginal group effect (p = 0.089, η² = 0.14), with larger differences between categories in dyslexia. VOT showed the expected effect of voicing, but no group differences. Conclusions: Our results indicate broadly preserved speech production in dyslexia, alongside subtle differences in category separation and size in dyslexia, marked by considerable inter-individual variability. Full article

While polyurethane acoustic foam is widely used in entertainment settings for sound absorption, it poses a considerable fire risk when exposed to sparks from pyrotechnic devices. Even though fountain-type pyrotechnic devices are often perceived as producing “cold sparks”, the ignition potential of a single incandescent particle remains insufficiently quantified. This study experimentally investigates the ignition capacity of a fountain-type pyrotechnic article on pyramidal polyurethane acoustic foam under controlled conditions. Three dedicated experimental configurations were developed: (i) ignition probability tests at various distances, (ii) scaled configuration tests reproducing realistic installation geometry, and (iii) high-speed visualization of single incandescent particle interaction with the foam surface. For the first two configurations, ignition probabilities of 20% and 22.2% were obtained. High-speed recordings showed two distinct interaction mechanisms: particle fragmentation and ricochet, which did not result in ignition; partial penetration with localized melting, volatile release, and gas-phase ignition when residual thermal energy (about 0.5–1 J) was retained. The results demonstrate that even isolated single incandescent particles generated under realistic conditions can initiate the combustion of polyurethane acoustic foam. These findings challenge the “cold spark” safety perception and provide quantitative evidence that particle–induced ignition represents a significant fire hazard in enclosed environments where combustible acoustic materials and pyrotechnic effects coexist. The findings in this paper have direct implications for safety regulations in entertainment venues. Full article

Understanding the unsteady aerodynamic behavior of quadrotor unmanned aerial vehicle (UAV) is critical for improving flight stability, control, and performance, particularly in complex operational environments. In closely spaced multirotor configurations, coherent tip vortices shed from each blade convect downstream and form helical vortex streets that interact with subsequent blades and neighboring rotors. These interactions induce rapid fluctuations in local inflow velocity and effective angle of attack, resulting in transient lift variations, increased vibratory loads, and elevated acoustic emissions. This study presents a comprehensive computational investigation of quadrotor rotor interactions and wake dynamics using a large-eddy simulation (LES). Detailed analyses reveal that the formation and evolution of tip vortices and blade–vortex interaction phenomena significantly influence lift fluctuations and aerodynamic loading. The simulations capture transient wake structures and their effects on neighboring rotors, highlighting unsteady aerodynamic mechanisms that are not adequately predicted by conventional RANS or URANS approaches. Parametric studies examining vortex-street offset distance demonstrate the sensitivity of wake-induced instabilities to design and operational parameters. The results provide new physical insights into multirotor wake dynamics and establish the LES as a predictive framework for quantifying unsteady aerodynamic loading in quadrotor drones. The findings provide insights into the complex flow physics of multirotor systems, offering guidance for more accurate modeling, rotorcraft design optimization, and the development of control strategies that mitigate adverse unsteady aerodynamic effects. This study provides new insights into rotor–vortex-street interactions, with applications to multirotor UAVs, by isolating multi-vortex coupling effects and quantifying the influence of horizontal vortex spacing on unsteady aerodynamic loading, complementing existing high-fidelity LES research. Full article

In the study of sensory processes, the visual system has received the most research compared to other sensory systems. The primary difference between visual and auditory perception lies in the nature of the stimuli and the reception processes: vision perceives electromagnetic radiation, while auditory perception perceives acoustic signals of mechanical origin. This review aims to analyze modern approaches and controversies to the mechanisms of auditory perception related to psychophysics, psychophysiology, psychopathology, modern research on hearing in human–computer interaction (HCI) systems, and machine learning methods. Modern studies of acoustic patterns include a comprehensive assessment of the physical characteristics of perception, complex nonverbal auditory cues, verbalization, perception and memory, as well as individual differences in auditory perception. An analysis of the scientific literature allowed us to conclude that acoustic signals transformed in the brain into auditory images retain (encode) a number of amplitude-temporal parameters of acoustic signals that facilitate auditory discrimination (filtering), but interfere with auditory detection (recognition). Signal processing often, but not necessarily, involves brain regions involved in other forms of perception. It depends on subvocalization, includes semantically interpreted information and expectations, pictorial (visual) and descriptive components, functions as a mnemonic, and is linked to individual musical ability and experience (although the mechanisms of this connection are unclear). Full article

With the growing demand for hybrid and electric vehicles, the accurate prediction of NVH (Noise, Vibration, and Harshness) behavior in Permanent Magnet Synchronous Machines (PMSMs) has become a critical aspect of electric motor design. This paper presents a detailed modeling approach for electromagnetic-induced noise and vibrations in PMSMs, integrating both analytical and numerical methods. The model focuses on quantifying the contributions of radial and tangential electromagnetic forces, which are key drivers of vibro-acoustic responses. The analytical part employs curved beam theory and a simplified acoustic model, offering rapid insights during early design stages. In parallel, a detailed numerical model based on finite element analysis is developed using a physics-based approach that accounts for the actual geometry and material properties of the PMSM prototype. This allows for enhanced accuracy without relying on experimental material parameter identification. Moreover, the detailed model includes the fluid–structure interaction introduced by the channels of the cooling fluid of the electric machine, which, although poorly addressed by the existing literature, was found to play a key role in driving the vibrational behaviour of the structure. By combining analytical speed with numerical precision, the proposed approach enables consistent and physically-based NVH predictions across various design phases, ultimately supporting improved electric machine performance and reducing development time and costs. Validation against experimental data confirms the ability of the model to accurately predict both sound pressure levels and housing surface vibrations. The novelty of this work lies in its integration of fluid–structure interaction and material modeling without the need for empirical parameter tuning, offering a robust tool for NVH design in electric vehicle applications. Full article

Surface Acoustic Wave (SAW) technology, long central to analog signal processing and RF filtering, is undergoing a major renewal. Driven by advances that decouple SAWs from traditional piezoelectric materials and fixed-function devices, the field is gaining unprecedented control over acoustic, optical, and electronic interactions at the micro and nanoscale. This review synthesizes these developments across four fronts: new physical mechanisms for SAW manipulation, emerging material platforms, ranging from thin films to 2D systems, along with reconfigurable device architectures and circuits, and the expanding landscape of applications they enable. Optical methods are reshaping how SAWs are generated and controlled, bypassing the limits of conventional electromechanical coupling. Coherent optical excitation of high-Q SAW cavities via Brillouin-like optomechanical interactions now grants access to modes in non-piezoelectric substrates such as diamond and silicon, while on-chip SAW excitation in photonic waveguides through backward stimulated Brillouin scattering opens new integrated sensing routes. In parallel, magneto-acoustic experiments have revealed nonreciprocal SAW diffraction from resonant scattering in magnetoelastic gratings. On the device side, ZnO thin-film transistors integrated on LiNbO₃ exploit acoustoelectric coupling to realize voltage-tunable phase shifters; UHF Z-shaped delay lines achieve high sensitivity in a compact footprint; and parametric synthesis of wideband, multi-stage lattice filters targets 5G-class performance. Atomistic simulations show that SAW propagation in 2D MXene films can be engineered via surface terminations, while aerosol jet printing and SAW-assisted particle patterning provide agile, cleanroom-light fabrication of microfluidic and magnetic components. These advances enable applications ranging from hybrid quantum systems and quantum links to lab-on-a-chip particle control, SBS-based and UHF sensing, reconfigurable RF front-ends, and soft robotic actuators based on patterned magnetic composites. At the same time, optical techniques offer non-contact probes of dissipation, and MXenes and other emerging materials open new regimes of acoustic control. Conclusively, they are transforming SAW technology into a versatile, programmable platform for mediating complex interactions in next-generation electronic, photonic, and quantum systems. Full article

This study presents a systematic review and an integrative interpretive synthesis of the architectural literature addressing sensory–interactive design strategies in early childhood learning environments that support children with Autism Spectrum Disorder (ASD), Down Syndrome (DS), and Attention Deficit Hyperactivity Disorder (ADHD). Following a systematic review conducted in accordance with PRISMA 2020 guidelines, twenty-nine peer-reviewed studies were analyzed to examine how environmental design variables may influence sensory load, cognitive processing, emotional stability, and behavioral engagement across neurodevelopmental profiles. Rather than remaining within conventional descriptive approaches, architectural variables—including lighting, color, acoustics, materials, spatial configuration, and environmental controllability—are reconceptualized as regulatory dimensions shaping child–environment interactions. The synthesis suggests that identical environmental variables may elicit divergent, and at times conflicting, sensory–emotional and behavioral responses among children with ASD, DS, and ADHD, highlighting the limitations of standardized design solutions. Accordingly, the study proposes the Sensory–Interactive Architecture Framework (SIAF), an analytical framework that links neurodevelopmental response patterns with sensory–emotional regulation mechanisms and environmental design variables as regulatory dimensions. The findings indicate that effective inclusive design does not rely on generalized sensory interventions but rather on the deliberate regulation of sensory variability through more legible, graded, and controllable spatial systems, thereby promoting learning engagement, emotional stability, and adaptive behavior in neurodiverse children. Full article

Underwater radiated noise (URN) has attracted increasing attention due to its environmental impact, with cavitation recognized as the dominant source. This study investigates cavitation-generation mechanisms and associated noise radiation for open-type and gap-type wings using high-fidelity numerical simulations. Cavitation noise was predicted using the Ffowcs Williams–Hawkings (FW–H) equation. The Fitzpatrick–Strasberg bubble noise model was independently employed for analysis to relate cavitation dynamics and cavity-volume variation to the resulting acoustic emissions. The results show that the gap-type configuration produces significantly stronger low-frequency noise, with the Tip Leakage Vortex Cavitation (TLVC) contributing up to 15 dB/Hz higher noise levels than the Tip Separation Vortex Cavitation (TSVC). This enhancement is attributed to the strong interaction between TLVC and TSVC, which amplifies cavitation dynamics and acoustic emissions. Analysis of three gap sizes reveals that, for small gaps, this interaction induces periodic cavitation behavior, generating a distinct harmonic component at St ≈ 2. As the gap size increases, the TLVC-TSVC interaction weakens, and the cavitation behavior transitions toward that of the open-type configuration, leading to the disappearance of the tonal component. These findings highlight the critical role of gap-induced vortex interaction in determining URN characteristics. Full article

Myocardial calcification is an uncommon complication associated with end-stage chronic kidney disease (CKD) in feline patients. This report describes the clinical and multimodal imaging features of metastatic calcification in a 10-year-old castrated male mixed-breed cat. The patient presented with dyspnea and anorexia, and was diagnosed with IRIS Stage 4 CKD. Laboratory findings revealed severe hyperphosphatemia and an elevated calcium–phosphorus product (CPP) of 135 mg²/dL², based on total calcium. This value significantly exceeds 70 mg²/dL², a threshold associated with a high probability of inducing soft tissue mineralization. Echocardiography revealed extensive hyperechoic foci with posterior acoustic shadowing in the interventricular septum and left ventricular wall. Functional assessment demonstrated a restrictive diastolic filling pattern, suggesting increased myocardial stiffness and congestive heart failure. Computed tomography (CT) further visualized systemic involvement, showing diffuse, amorphous calcifications (400–900 HU) in the myocardium, multifocal aortic wall, and extracardiac tissues. Despite intensive treatment with diuretics and renal support, the patient was euthanized eight days later due to progressive renal failure. This case illustrates that the interaction between metastatic calcification and uremic cardiomyopathy (UC) can result in refractory heart failure, underscoring the value of combined echocardiography and CT in evaluating end-stage renal disease. Full article

Lanyin Mandarin is a major regional variety of Mandarin Chinese with phonological characteristics that interact with the acquisition of the codified Standard Mandarin norm. This study examined the pronunciation of Standard Mandarin by 67 native speakers from the Lanyin Mandarin area using a large-scale subjective listening experiment (12 listeners, 6700 tokens), with deviations analyzed across initial consonants, finals, and tones. Based on the perceptual results, a pronunciation deviation database was established (N = 20,100 monosyllabic tokens), enabling targeted acoustic comparisons with Standard Mandarin. The results reveal several systematic patterns with quantified deviation rates. For initial consonants, the highest deviation rates were observed for /l/→/n/ (30.5%), /s/→/ts/ (25.5%), and /ts^h/→/ts/ (20.2%), significantly exceeding their reverse substitutions (/n/→/l/: 13.3%, /ts/→/s/: 0.0%, /ts/→/ts^h/: 15.4%; all p < 0.001). For finals, /iŋ/→/in/ showed the strongest asymmetry (61.2% vs. 21.9% for the reverse), followed by /əŋ/→/ən/ (40.2%) and /ən/→/əŋ/ (39.2%). Tonal deviations were dominated by Tone 3 identified as Tone 2 (31.7%), with Tone 1→Tone 2 at a lower rate (8.4%). These deviations exhibited significant directional asymmetries (e.g., /l/→/n/ vs. /n/→/l/: χ²(1) = 768.06, p < 0.001). Acoustic analyses indicated that consonant confusions corresponded to F2/F3 formant convergence (e.g., Lanyin-biased /l/ F2 values approached Standard Mandarin /n/), while nasal finals showed F2 fronting (higher F2 values approaching Standard Mandarin /in/). Tonal analyses revealed a compressed pitch range (2.4 semitones narrower than Standard Mandarin), with flattened Tone 3 contours contributing to Tone 2 confusion. Together, these findings demonstrate quantifiable, systematic, and directional phonetic patterns in the acquisition of Standard Mandarin by Lanyin dialect speakers, supported by converging perceptual and acoustic evidence. Full article

This paper presents a theoretical approach based on the FSDT to study the acoustic vibration performance of rib-stiffened PVC foam sandwich structures with reinforcing and weakening phases when submerged in water. The complex core layer with reinforcing and weakening phases is homogenized to an equivalent orthotropic layer. Building upon this framework, the governing equations of motion for rib-stiffened PVC foam sandwich structures under the boundary conditions of a simply supported type are derived, incorporating the coupling interaction between the reinforcing ribs and the sandwich plates. Considering the influence of the underwater environment, with the Helmholtz equation governing the continuity of the acoustic pressure field and the Euler equation regulating the fluid–structure interaction interface continuity, the Navier method is subsequently employed to solve for the natural frequencies and acoustic vibration responses. For the purpose of verifying the proposed approach, the predicted results are contrasted with both the literature-derived data and numerical simulation results. Finally, parametric research is further conducted to explore the effect of the parameters of the rib and core layers on the underwater acoustic vibration characteristics. The conclusions drawn from this study can provide meaningful guidance for engineering design and optimization of such rib-stiffened sandwich structures, incorporating both reinforcing and weakening phases in underwater engineering applications. Full article