{"title":"Optimised implicit finite-difference schemes for the wave equation with admittance boundary conditionsa).","authors":"Jan W Smits, Stefan Bilbao","doi":"10.1121/10.0036229","DOIUrl":"https://doi.org/10.1121/10.0036229","url":null,"abstract":"<p><p>Wave-based acoustic simulation offers, in theory, a complete solution to the problem of room auralisation. In practice, however, the computational requirements of such simulations, in terms of both computation time and memory usage are very large even for moderately-sized rooms. In this article, a family of implicit finite-difference schemes is described that can enable simulation over the full audio bandwidth up to 20 kHz. When optimised against a wideband error criterion, the schemes' improved numerical accuracy allows a coarse grid resolution to be used, in turn leading to reduced computational times and memory usage compared with commonly used explicit methods. The schemes are complemented by provably stable admittance boundaries over a general staircased geometry. Various numerical examples illustrate the stability, accuracy and performance results achieved with the optimised schemes.</p>","PeriodicalId":17168,"journal":{"name":"Journal of the Acoustical Society of America","volume":"157 3","pages":"2168-2179"},"PeriodicalIF":2.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143709609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jeff Tucker, Kathleen E Wage, John R Buck, Lora J Van Uffelen
{"title":"Performance weighted blended spectrogram.","authors":"Jeff Tucker, Kathleen E Wage, John R Buck, Lora J Van Uffelen","doi":"10.1121/10.0036216","DOIUrl":"https://doi.org/10.1121/10.0036216","url":null,"abstract":"<p><p>Spectrograms are used for time-frequency analysis and as preprocessing for signal classifiers and other algorithms. The conventional spectrogram is a tapered short-time Fourier transform, equivalent to a bank of bandpass filters. The taper defines filter-bank characteristics such as bandwidth and sidelobe levels. Although the conventional spectrogram uses minimal computational resources, its design requires a compromise between resolution and interference suppression. Adaptive spectrogram algorithms adjust the filter-bank based on incoming data, thereby allowing different bandwidth/sidelobe trade-offs at each frequency and time. Adaptation can simultaneously improve tonal resolution and reveal quiet sources but typically costs substantially more to implement. This paper presents an adaptive spectrogram designed for applications with limited computational resources, e.g., autonomous vehicles. The performance weighted blended (PWB) spectrogram combines the output of a set of conventional filter-banks designed with different tapers. By adapting its blend weights at each frequency and time, the new algorithm separates loud closely spaced tones and identifies quiet signals. Because it relies on conventional filter-banks, the PWB spectrogram requires significantly less computation than other adaptive algorithms that require expensive matrix computations. Analysis of underwater glider data demonstrates the algorithm's ability to reveal a quiet chirp signal in the presence of vehicle self-noise.</p>","PeriodicalId":17168,"journal":{"name":"Journal of the Acoustical Society of America","volume":"157 3","pages":"2106-2116"},"PeriodicalIF":2.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143709841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marius Walther, André Gerlach, Marko Liebler, Christoph Haugwitz, Mario Kupnik
{"title":"A method for approximating high frequency sound radiation-The plane projection Rayleigh integral.","authors":"Marius Walther, André Gerlach, Marko Liebler, Christoph Haugwitz, Mario Kupnik","doi":"10.1121/10.0036130","DOIUrl":"https://doi.org/10.1121/10.0036130","url":null,"abstract":"<p><p>The sound radiation of vibrating surfaces can be calculated using integral-based numerical methods. Due to the increasing discretization requirements, the computational effort increases significantly with increasing frequencies. Therefore, approximation methods with less computational effort are desirable. This paper introduces a method called the plane projection Rayleigh integral (PPRI), which combines low computational effort with high precision. The method approximates the sound radiation by applying the Rayleigh integral to a vibrating virtual plane representing the object in two dimensions. The method's performance is evaluated by comparing it to the visible element Rayleigh integral and the high frequency boundary element method (HFBEM), focusing on the accuracy and its dependence on radius of surface curvature, sound frequency, and distance from the surface. Analytical solutions for the breathing and oscillating sphere are used as benchmarks. The PPRI demonstrates the highest accuracy among the methods tested. Error values decrease significantly with larger radii and higher frequencies, falling below a 1% threshold at 4 times smaller Helmholtz numbers (radius-wavelength ratio) than the HFBEM. Additionally, the PPRI requires the least computational time in this consideration. Thus, the PPRI achieves both high precision and efficiency.</p>","PeriodicalId":17168,"journal":{"name":"Journal of the Acoustical Society of America","volume":"157 3","pages":"1714-1725"},"PeriodicalIF":2.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143615782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Roberto Yubero, Christ A F de Jong, Michael A Ainslie, Alexander O MacGillivray, Lian Wang
{"title":"Measuring vessel source level in shallow water using the smoothed semi-coherent image method.","authors":"Roberto Yubero, Christ A F de Jong, Michael A Ainslie, Alexander O MacGillivray, Lian Wang","doi":"10.1121/10.0036140","DOIUrl":"https://doi.org/10.1121/10.0036140","url":null,"abstract":"<p><p>Standardizing the process for measuring underwater sound generated by ships in shallow waters is a complex challenge currently under development. Recent progress has enabled the development of analytical formulations to represent propagation conditions underwater using propagation loss (PL) approximations, which are employed to derive the source level (SL) from ship sound pressure level (SPL) measurements. Underwater radiated noise (URN) tests conducted in the SATURN project enabled a detailed evaluation of the seabed critical angle (SCA) method, recommended by an early draft of the ongoing ISO 17208-3 standard, identifying a general underestimation of SL above ∼500 Hz compared to measurements under equivalent operating conditions in deep water, as described by ISO 17208-1. This article presents an alternative smoothed semi-coherent image (SSCI) method for calculating PL (and hence SL) and assesses the method's performance through analytical and empirical scenarios (including recordings of three different instrumentation deployment strategies at four distinct depths and four test distances). The SSCI method enhances accuracy over a broad frequency range while maintaining the general robustness, with a formulation that also seeks to preserve the simplicity of the SCA approach.</p>","PeriodicalId":17168,"journal":{"name":"Journal of the Acoustical Society of America","volume":"157 3","pages":"1938-1954"},"PeriodicalIF":2.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143674208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Perceptual weighting strategies of adolescents with normal hearing or cochlear implants.","authors":"Susan Nittrouer","doi":"10.1121/10.0036128","DOIUrl":"10.1121/10.0036128","url":null,"abstract":"<p><p>The distribution of perceptual attention across the myriad acoustic properties of speech undergoes developmental shifts through the first decade of life, changing from a focus on dynamic spectral structure to other kinds of temporal, amplitude, and static spectral properties. These developmental changes accompany a gradual enhancement in sensitivity to phonological structure. A central question concerning spoken language acquisition by children with hearing loss who use cochlear implants (CIs) concerns how they navigate these developmental changes and what effect signal degradation has on developing language abilities, especially sensitivity to phonological structure. To explore these questions, this report describes outcomes of data collected from adolescents with normal hearing and adolescents with CIs. Perceptual weighting factors were computed for static and dynamic spectral properties using a fricative-vowel labeling paradigm. Measures of speech recognition, language abilities, word reading, and phonological processing were also obtained. Results showed that the adolescents with CIs weighted dynamic spectral structure hardly at all. Weighting of static spectral structure was largely related to their abilities to manipulate and retain phonological structure in memory. Overall, these findings indicate that supporting developmental shifts in perceptual weighting strategies should remain a goal of intervention for children with hearing loss who use CIs.</p>","PeriodicalId":17168,"journal":{"name":"Journal of the Acoustical Society of America","volume":"157 3","pages":"1742-1760"},"PeriodicalIF":2.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11908816/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143625166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Daniel Herburger, Jin-Yeon Kim, Nicholas Lark, Laurence Jacobs
{"title":"Evaluating effects of microstructure and porosity on elastic anisotropy of additively manufactured materials using ultrasonic techniques.","authors":"Daniel Herburger, Jin-Yeon Kim, Nicholas Lark, Laurence Jacobs","doi":"10.1121/10.0036214","DOIUrl":"https://doi.org/10.1121/10.0036214","url":null,"abstract":"<p><p>The potential of additive manufacturing is often limited by qualification issues, particularly due to process defects such as lack-of-fusion porosity and highly anisotropic elastic properties. This research demonstrates the ability of ultrasonic measurement techniques to assess these elastic properties, process defects, and microstructural characteristics. Ultrasonic velocity measurements are used to evaluate the impact of various process parameters and heat treatments (HTs) on the elastic anisotropy of laser powder bed fusion 316 L stainless steel. These variations are linked to material characteristics through microstructural analysis and porosity measurements. By characterizing the orthotropic elastic behavior, this study quantifies the errors that can arise in the design and analysis of additively manufactured parts by assuming isotropic or transversely isotropic elastic properties. Furthermore, HTs are used to isolate and quantify the individual contributions of process defects such as lack-of-fusion defects and microstructural factors-including crystallographic texture and grain morphology-to elastic anisotropy. The findings of this research highlight the potential of ultrasonic techniques for monitoring and qualifying additively manufactured materials.</p>","PeriodicalId":17168,"journal":{"name":"Journal of the Acoustical Society of America","volume":"157 3","pages":"2018-2028"},"PeriodicalIF":2.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143692513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mechanical impedance of the skin-covered human head at different stimulation positions, static forces, and interface areas.","authors":"Sudeep Surendran, Stefan Stenfelt","doi":"10.1121/10.0036150","DOIUrl":"https://doi.org/10.1121/10.0036150","url":null,"abstract":"<p><p>Bone conduction (BC) transducers applied to skin-covered areas of the head differ in their positioning, contact area, and static force, all of which influence output characteristics. This study assesses the mechanical impedance of the skin-covered head under varying conditions. Measurements were conducted on 30 participants at 3 positions, earfront, forehead, and mastoid, using circular interfaces with diameters of 10, 15, and 25 mm, and 6 static forces ranging from 0.5 to 7 N. Results showed that mechanical impedance was stiffness-controlled below the resonance frequency and mass-controlled above it. Low-frequency impedance depended on position and static force, with the forehead producing the highest impedance magnitude and the earfront producing the lowest impedance magnitude. At high frequencies, impedance across positions was similar, except for the mastoid with 25 mm interface. Impedance magnitude increased with interface area below 350 Hz and above resonance frequency. These findings highlight an impedance mismatch between standard artificial mastoids and human mastoids, potentially leading to inaccurate force estimations in BC devices. Additionally, three-element and six-element lumped mechanical models for the earfront, forehead, and mastoid were developed, with parameter values as function of contact area and static force.</p>","PeriodicalId":17168,"journal":{"name":"Journal of the Acoustical Society of America","volume":"157 3","pages":"1821-1841"},"PeriodicalIF":2.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143649396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Successive weight update sparse Bayesian learning based receiver for multiuser underwater acoustic communications.","authors":"Xueli Sheng, Zheng Wu, Li Wei, Guangjun Zhu, Xiao Han, Yanan Tian","doi":"10.1121/10.0036141","DOIUrl":"https://doi.org/10.1121/10.0036141","url":null,"abstract":"<p><p>This paper proposes a single-carrier multiuser (MU) receiver for MU underwater acoustic communications with time-varying and strong multiple-access interference. The receiver integrates soft successive interference cancellation, successive weight update sparse Bayesian learning channel estimation based on approximate message passing (SWUSBL-AMP), and an improved channel update decision. After the first iteration, the improved channel update decision first estimates the channel of each subblock using the interference-cancelled signals from the previous iteration, avoiding the mismatch of time-varying channels. By running the factor graph serially, the SWUSBL-AMP channel estimation algorithm enables the factor graph of the current subblock to utilize the messages updated by the previous subblock, and update the correlation weighting factors, to accelerate the convergence speed and further improve the channel estimation accuracy. Using the experimental data collected in the South China Sea in 2023 for processing, the results demonstrate that the bit error rate performance of the proposed receiver is better than that of other receivers of the same type. Moreover, we also verify the complexity of the proposed SWUSBL-AMP algorithm can be nearly an order of magnitude lower than that of other algorithms.</p>","PeriodicalId":17168,"journal":{"name":"Journal of the Acoustical Society of America","volume":"157 3","pages":"1807-1820"},"PeriodicalIF":2.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143649399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Statistical wave field theory: Special polyhedra.","authors":"Roland Badeau","doi":"10.1121/10.0036254","DOIUrl":"https://doi.org/10.1121/10.0036254","url":null,"abstract":"<p><p>The statistical wave field theory establishes mathematically the statistical laws of the solutions to the wave equation in a bounded volume. It provides the closed-form expression of the power distribution and the correlations of the wave field jointly over time, frequency, and space, in terms of the geometry and the specific admittance of the boundary surface. In a recent paper, we presented a mathematical approach to this theory based on the Sturm-Liouville theory and the theory of dynamical billiards. We focused on mixing billiards that generate an isotropic wave field, and we retrieved the well-known statistical properties of reverberation in room acoustics. In the present paper, we introduce a simpler geometric approach, dedicated to a particular class of non-ergodic billiards. Though limited to only a few polyhedra, this approach offers a precious insight into various aspects of the theory, including the first examples of anisotropic wave fields, whose statistical properties are related to mathematical crystallography. We also show that the formulas that we obtain in this anisotropic case are closely related to those of the mixing case, albeit based on a different mathematical approach.</p>","PeriodicalId":17168,"journal":{"name":"Journal of the Acoustical Society of America","volume":"157 3","pages":"2263-2278"},"PeriodicalIF":2.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143730543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Activity-based acoustic situations in primary schools: Analyzing classroom noise and listening effort.","authors":"Julia Seitz, Janina Fels","doi":"10.1121/10.0036129","DOIUrl":"https://doi.org/10.1121/10.0036129","url":null,"abstract":"<p><p>This study introduces the concept of activity-based acoustic situations in primary schools, which describe the everyday sound environment in classrooms. During a series of noise measurements in seven German primary schools, differences in noise parameters and subjective listening effort, as assessed by questionnaires, were investigated across the activity-based acoustic situations. Classroom noise was analyzed for sound pressure level (SPL), A-weighted SPL, loudness, and sharpness. The results showed statistically significant differences in average loudness and A-weighted SPL between the activity-based acoustic situations, with silent work yielding 55.48 dB(A), student-teacher interaction 65.13 dB(A), group work 67.44 dB(A), and breakfast break in the classroom 69.34 dB(A). All loudness parameters, SPL, A-weighted SPL, and loudness, showed higher values for first grade than for fourth grade supporting that noise levels decrease with increasing age. Subjective listening effort, as assessed by questionnaires, did not differ significantly between activity-based acoustic situations. This suggests that the questionnaire may not have been suited to evaluate subjective listening effort for the age group investigated. The present study highlights the importance of activity-based assessment of classroom noise to better represent the classroom sound environment.</p>","PeriodicalId":17168,"journal":{"name":"Journal of the Acoustical Society of America","volume":"157 3","pages":"1772-1783"},"PeriodicalIF":2.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143625147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}