Publisher: ASA   (Total: 2 journals)   [Sort by number of followers]

Showing 1 - 2 of 2 Journals sorted alphabetically
J. of the Acoustical Society of America     Full-text available via subscription   (Followers: 57, SJR: 0.695, CiteScore: 2)
Proceedings of Meetings on Acoustics     Open Access   (Followers: 14)
Similar Journals
Journal Cover
Journal of the Acoustical Society of America
Journal Prestige (SJR): 0.695
Citation Impact (citeScore): 2
Number of Followers: 57  
 
  Full-text available via subscription Subscription journal
ISSN (Print) 0001-4966 - ISSN (Online) 1520-8524
Published by ASA Homepage  [2 journals]
  • Acoustical News

    • Free pre-print version: Loading...

      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1970-1993, September 2022.
      Editor's Note: Readers of this journal are encouraged to submit news items on awards, appointments, and other activities about themselves or their colleagues. Deadline dates for news and notices are 2 months prior to publication.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-30T11:14:42Z
       
  • An integrated approach for teaching speech spectrogram analysis to
           engineering students

    • Free pre-print version: Loading...

      Authors: Alexander Johnson
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1962-1969, September 2022.
      Spectrogram analysis is a vital skill for learning speech acoustics. Spectrograms are necessary for visualizing cause-effect relationships between speech articulator movements and the resulting sound produced. However, many interpretation techniques needed to read spectrograms are counterintuitive to engineering students who have been taught to use more rigid mathematical formulas. As a result, spectrogram reading is often challenging for these students who do not have prior background in acoustic phonetics. In this paper, a structured, inclusive framework for teaching spectrogram reading to students of engineering backgrounds is presented. Findings from the implementation of these teaching methods in undergraduate and graduate engineering courses at University of California, Los Angeles are also unveiled.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-30T11:14:41Z
       
  • Influence of tessellation morphology on ultrasonic scattering

    • Free pre-print version: Loading...

      Authors: Showmic Islam, Musa Norouzian, Joseph A. Turner
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1951-1961, September 2022.
      Material properties, such as hardness, yield strength, and ductility, depend on the microstructure of the material. If the microstructural organization can be quantified nondestructively, for example, with ultrasonic scattering techniques, then it may be possible to predict the mechanical performance of a component. Three-dimensional digital microstructures have been increasingly used to investigate the scattering of mechanical waves within a numerical framework. These synthetic microstructures can be generated using different tessellation algorithms that result in different grain shapes. In this study, the variation of ultrasonic scattering is calculated for microstructures of different morphologies for a nickel polycrystal. The ultrasonic properties are calculated for the Voronoi, Laguerre tessellations, and voxel-based synthetic microstructures created by DREAM.3D. The results show that the differences in the two-point statistics and ultrasonic attenuation for different morphologies become more significant at wider size distributions and higher frequencies.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-27T02:04:40Z
       
  • Optimize multilayer matching layer design for tone-burst underwater
           acoustic transducers

    • Free pre-print version: Loading...

      Authors: Chunying Wang, Cong Wang, Naitao Liu, Yu Lan, Wenwu Cao
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1942-1950, September 2022.
      In this study, a theoretical model has been constructed to address the optimization of matching layers for tone burst excitation underwater acoustic transducers and to investigate the functional mechanism change of matching layers. Single, double, and triple matching layers are attached to piezoelectric composite plates, and tone burst signals with a different number of burst-cycles are applied. Acoustic pressure function (Sp) and acoustic pressure transient response (PTR) are compared among these transducers. The results demonstrated that when the cycle number M ≤ 2, more matching layers lead to shorter ringdown with similar PTR amplitude. Since the objective is for better axial resolution, three matching layers have noticeable advantage, whereas for the case of M > 5, far detection distance is the main objective, and more matching layers caused the decrease in PTR amplitude. Besides, matching layers become part of the resonance structure; they do not serve as a transmission medium anymore. Therefore, the transducer with single matching is optimal for the long tone burst excitation. For the case of 2–5 cycle excitation, one may use double matching layers, which has a balance between the transmitting voltage response amplitude and bandwidth. With the increase in M, the role of matching layers changes from a bridging transmission medium to amplifying vibration velocity and introducing additional vibration modes to broaden the bandwidth.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-27T02:04:35Z
       
  • The ACOUCOU platform: Online acoustic education developed by an
           interdisciplinary team

    • Free pre-print version: Loading...

      Authors: Karolina Jaruszewska, Manuel Melon, Olivier Dazel, Michael Vorländer, Monika Rychtáriková, Marko Horvat, Thomas Wulfrank, Andreas Herweg, Lukas Aspöck, Yannick Sluyts, Kristian Jambrošić, Emilie Carayol, Błażej Wojtyła, Marcin Łuczak, Vojtech Chmelík
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1922-1931, September 2022.
      The ACOUCOU platform is a web-based, interactive, acoustics training platform that includes a set of free educational materials in various technical fields of acoustics. Educational materials are designed to serve as a modern self-development tool for students and engineers, as well as a comprehensive solution for professional education in the work environment. On the other hand, the provided materials of the platform can be a useful tool, supporting teachers, company researchers, and academic lecturers in the process of teaching acoustics. The ACOUCOU platform is a part of a strategic plan for expanding and strengthening acoustic knowledge web-based tools and supporting the development of innovative teaching methods based on attractive and effective delivery of digital content, and best practices at national and international levels. It addresses the challenge of a lack of experts in the acoustics field and the growing needs of the market.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-26T11:49:43Z
       
  • Project-based learning through sensor characterization in a musical
           acoustics course

    • Free pre-print version: Loading...

      Authors: Valerie Rennoll, Ian McLane, Adebayo Eisape, Drew Grant, Claudius Betz, Xinyao Chen, Michael Gebhart, Helena Hahn, Samuel Kartub, Brenden Lehr, Cuauhtémoc Méndez Suárez, Randall Smith, Noah Tingen, Thomas Tyra, Fengji Yang, James E. West
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1932-1941, September 2022.
      Project-based learning engages students in practical activities related to course content and has been demonstrated to improve academic performance. Due to its reported benefits, this form of active learning was incorporated with an ongoing research project into an introductory, graduate-level Musical Acoustics course at the Peabody Institute of The Johns Hopkins University. Students applied concepts from the course to characterize a contact sensor with a polymer diaphragm for musical instrument recording. Assignments throughout the semester introduced students to completing a literature review, planning an experiment, collecting and analyzing data, and presenting results. While students were given broad goals to understand the performance of the contact sensor compared to traditional microphones, they were allowed independence in determining the specific methods used. The efficacy of the course framework and research project was assessed with student feedback provided through open-ended prompts and Likert-type survey questions. Overall, the students responded positively to the project-based learning and demonstrated mastery of the course learning objectives. The work provides a possible framework for instructors considering using project-based learning through research in their own course designs.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-26T11:49:41Z
       
  • Autonomous characterization of grain size distribution using nonlinear
           Lamb waves based on deep learning

    • Free pre-print version: Loading...

      Authors: Lishuai Liu, Peng Wu, Yanxun Xiang, Fu-Zhen Xuan
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1913-1921, September 2022.
      Characterization of grain microstructures of metallic materials is crucial to materials science and engineering applications. Unfortunately, the universal electron microscopic methodologies can only capture two-dimensional local observations of the microstructures in a time-consuming destructive way. In this regard, the nonlinear ultrasonic technique shows the potential for efficient and nondestructive microstructure characterization due to its high sensitivity to microstructural features of materials, but is hindered by the ill-posed inverse problem for multiparameter estimation induced by the incomplete understanding of the complicated nonlinear mechanical interaction mechanism. We propose an explainable nonlinearity-aware multilevel wavelet decomposition-multichannel one-dimensional convolutional neural network to hierarchically extracts multilevel time-frequency features of the acoustic nonlinearity and automatically model latent nonlinear dynamics directly from the nonlinear ultrasonic responses. The results demonstrate that the proposed approach establishes the complex mapping between acoustic nonlinearity and microstructural features, thereby determining the lognormal distribution of grain size in metallic materials rather than only average grain size. In the meantime, the integration of the designed nonlinearity-aware network and the quantitative analysis of component importance provides an acceptable physical explainability of the deep learning approach for the nonlinear ultrasonic technique. Our study shows the promise of this technique for real-time in situ evaluation of microstructural evolution in various applications.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-23T11:36:04Z
       
  • On H1–H2 as an acoustic measure of linguistic phonation type

    • Free pre-print version: Loading...

      Authors: Yuan Chai, Marc Garellek
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1856-1870, September 2022.
      The measure H1–H2, the difference in amplitude between the first and second harmonics, is frequently used to distinguish phonation types and to characterize differences across voices and genders. While H1–H2 can differentiate voices and is used by listeners to perceive changes in voice quality, its relation to voice articulation is less straightforward. Its calculation also involves practical issues with error propagation. This paper highlights some developments in the use of H1–H2 and proposes a new measure that we call “residual H1.” In residual H1, the amplitude of the first harmonic is normalized against the overall sound energy (as measured by root mean square energy) instead of against H2. Residual H1 may mitigate some of the issues with using H1–H2. The current study tests the correlation between residual H1 and electroglottographic contact quotient (CQ) and compares the ability of residual H1 vs H1–H2 to differentiate statistically across phonation types in !Xóõ and utterance-level changes in phonatory quality in Mandarin. The results show that residual H1 has a stronger correlation with CQ and differentiates contrastive and allophonic phonatory quality better than H1–H2, particularly for more constricted phonation types.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-23T11:36:01Z
       
  • The auditory perceived aperture position of the transition between rooms

    • Free pre-print version: Loading...

      Authors: Thomas McKenzie, Sebastian J. Schlecht, Ville Pulkki
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1871-1882, September 2022.
      This exploratory study investigates the phenomenon of the auditory perceived aperture position (APAP): the point at which one feels they are in the boundary between two adjoined spaces, judged only using auditory senses. The APAP is likely the combined perception of multiple simultaneous auditory cue changes, such as energy, reverberation time, envelopment, decay slope shape, and the direction, amplitude, and colouration of direct and reverberant sound arrivals. A framework for a rendering-free listening test is presented and conducted in situ, avoiding possible inaccuracies from acoustic simulations, impulse response measurements, and auralisation to assess how close the APAP is to the physical aperture position under blindfold conditions, for multiple source positions and two room pairs. Results indicate that the APAP is generally within [math] m of the physical aperture position, though reverberation amount, listener orientation, and source position affect precision. Comparison to objective metrics suggests that the APAP generally falls within the period of greatest acoustical change. This study illustrates the non-trivial nature of acoustical room transitions and the detail required for their plausible reproduction in dynamic rendering and game audio engines.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-23T11:35:59Z
       
  • Influences of piezoelectric positive-negative junction on the multi-field
           coupled waves propagation in the piezoelectric semiconductor

    • Free pre-print version: Loading...

      Authors: Zibo Wei, Peijun Wei, Chunyu Xu, Xiao Guo
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1883-1900, September 2022.
      The influences of the piezoelectric positive-negative junction (PN junction) between two semiconductors with different doping types on the multi-field coupled wave propagation are studied in the present work. The layered structures of semiconductors are often used in intelligent devices, and the PN junction plays an important role for performance improvement. Due to the migration and diffusion of carriers, the electric potential and concentration of the carrier are graded distribution in the PN junction. This inhomogeneity results in the reflection and transmission of coupled waves, which are the complex of multiple physical fields including the mechanical, electric, and carrier fields. The state transfer equation method is used to obtain the transfer matrix of the PN junction, and the reflection and transmission waves under the plane strain situation are evaluated numerically. The energy fluxes of the reflection and transmission waves are estimated and used to validate the numerical results by the check of energy conservation. It is found that PN junction effects hinder the wave propagation and drastically enhance the reflection ability of the interface, especially, on the coupled carrier waves, and thus are very important and cannot be ignored for the wave propagation problem. The influences of external applied stress and bias electric field are also discussed.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-23T11:35:58Z
       
  • Ultrasound characterization of the viscoelastic properties of additively
           manufactured photopolymer materials

    • Free pre-print version: Loading...

      Authors: Max Gattin, Nicolas Bochud, Giuseppe Rosi, Quentin Grossman, Davide Ruffoni, Salah Naili
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1901-1912, September 2022.
      Photopolymer-based additive manufacturing has received increasing attention in the field of acoustics over the past decade, specifically towards the design of tissue-mimicking phantoms and passive components for ultrasound imaging and therapy. While these applications rely on an accurate characterization of the longitudinal bulk properties of the materials, emerging applications involving periodic micro-architectured media also require the knowledge of the transverse bulk properties to achieve the desired acoustic behavior. However, a robust knowledge of these properties is still lacking for such attenuating materials. Here, we report on the longitudinal and transverse bulk properties, i.e., frequency-dependent phase velocities and attenuations, of photopolymer materials, which were characterized in the MHz regime using a double through-transmission method in oblique incidence. Samples were fabricated using two different printing technologies (stereolithography and polyjet) to assess the impact of two important factors of the manufacturing process: curing and material mixing. Overall, the experimentally observed dispersion and attenuation could be satisfactorily modeled using a power law attenuation to identify a reduced number of intrinsic ultrasound parameters. As a result, these parameters, and especially those reflecting transverse bulk properties, were shown to be very sensitive to slight variations of the manufacturing process.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-23T11:35:56Z
       
  • A wave glider-based, towed hydrophone array system for autonomous,
           real-time, passive acoustic marine mammal monitoring

    • Free pre-print version: Loading...

      Authors: Vincent E. Premus, Philip A. Abbot, Vitaly Kmelnitsky, Charles J. Gedney, Ted A. Abbot
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1814-1828, September 2022.
      An autonomous surface vehicle known as a wave glider, instrumented with a low-power towed hydrophone array and embedded digital signal processor, is demonstrated as a viable low-noise system for the passive acoustic monitoring of marine mammals. Other key design elements include high spatial resolution beamforming on a 32-channel towed hydrophone array, deep array deployment depth, vertical motion isolation, and bandwidth-efficient real-time acoustic data transmission. Using at-sea data collected during a simultaneous deployment of three wave glider-based acoustic detection systems near Stellwagen Bank National Marine Sanctuary in September 2019, the capability of a low-frequency towed hydrophone array to spatially reject noise and to resolve baleen whale vocalizations from anthropogenic acoustic clutter is demonstrated. In particular, mean measured array gain of 15.3 dB at the aperture design frequency results in a post-beamformer signal-to-noise ratio that significantly exceeds that of a single hydrophone. Further, it is shown that with overlapping detections on multiple collaborating systems, precise localization of vocalizing individuals is achievable at long ranges. Last, model predictions showing a 4× detection range, or 16× area coverage, advantage of a 32-channel towed array over a single hydrophone against the North Atlantic right whale upcall are presented for the continental shelf environment south of Martha's Vineyard.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-22T11:36:36Z
       
  • Effects of atmospheric refraction on detecting elevated sources with
           beamforming algorithms

    • Free pre-print version: Loading...

      Authors: Geoffrey H. Goldman
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1829-1841, September 2022.
      Classical beamforming algorithms are based on rectilinear propagation of signals that are corrupted by additive noise. However, sound waves propagating in the atmosphere are refracted by temperature and wind gradients and distorted by turbulence and scattering from the ground. These effects can reduce the performance of acoustic systems. To investigate these effects, a simulation capability is used to propagate signals from elevated sources to an array of microphones near the ground. Detection algorithms based on four standard beamforming algorithms, implemented with either no model mismatch error or model mismatch errors generated by atmospheric refraction, are tested. The results are evaluated using the area under the receiver operating characteristic curve statistic. The analysis shows no significant improvement in detection performance when refraction effects are included in the beamforming algorithms over a wide range of frequencies. Any small performance improvements achieved by incorporating refraction effects into the beamforming algorithms are overwhelmed by the negative effects of atmospheric turbulence and rough surface scattering. For the selected scenario, incorporating refraction effects into the beamformers is over-engineering. These results demonstrate some of the limitations of developing new signal processing algorithms or array designs for atmospheric acoustic systems.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-22T11:36:35Z
       
  • Nonspeech sounds are not all equally good at being nonspeech

    • Free pre-print version: Loading...

      Authors: Christian E. Stilp, Anya E. Shorey, Caleb J. King
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1842-1849, September 2022.
      Perception of speech sounds has a long history of being compared to perception of nonspeech sounds, with rich and enduring debates regarding how closely they share similar underlying processes. In many instances, perception of nonspeech sounds is directly compared to that of speech sounds without a clear explanation of how related these sounds are to the speech they are selected to mirror (or not mirror). While the extreme acoustic variability of speech sounds is well documented, this variability is bounded by the common source of a human vocal tract. Nonspeech sounds do not share a common source, and as such, exhibit even greater acoustic variability than that observed for speech. This increased variability raises important questions about how well perception of a given nonspeech sound might resemble or model perception of speech sounds. Here, we offer a brief review of extremely diverse nonspeech stimuli that have been used in the efforts to better understand perception of speech sounds. The review is organized according to increasing spectrotemporal complexity: random noise, pure tones, multitone complexes, environmental sounds, music, speech excerpts that are not recognized as speech, and sinewave speech. Considerations are offered for stimulus selection in nonspeech perception experiments moving forward.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-22T11:36:33Z
       
  • Molecular analysis of individual differences in talker search at the
           cocktail-party

    • Free pre-print version: Loading...

      Authors: Robert A. Lutfi, Torben Pastore, Briana Rodriguez, William A. Yost, Jungmee Lee
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1804-1813, September 2022.
      A molecular (trial-by-trial) analysis of data from a cocktail-party, target-talker search task was used to test two general classes of explanations accounting for individual differences in listener performance: cue weighting models for which errors are tied to the speech features talkers have in common with the target and internal noise models for which errors are largely independent of these features. The speech of eight different talkers was played simultaneously over eight different loudspeakers surrounding the listener. The locations of the eight talkers varied at random from trial to trial. The listener's task was to identify the location of a target talker with which they had previously been familiarized. An analysis of the response counts to individual talkers showed predominant confusion with one talker sharing the same fundamental frequency and timbre as the target and, secondarily, other talkers sharing the same timbre. The confusions occurred for a roughly constant 31% of all of the trials for all of the listeners. The remaining errors were uniformly distributed across the remaining talkers and responsible for the large individual differences in performances observed. The results are consistent with a model in which largely stimulus-independent factors (internal noise) are responsible for the wide variation in performance across listeners.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-22T11:36:31Z
       
  • Classification of simulated complex echoes based on highlight time
           separation in the bottlenose dolphin (Tursiops truncatus)

    • Free pre-print version: Loading...

      Authors: Alyssa W. Accomando, Jason Mulsow, Dorian S. Houser, James J. Finneran
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1795-1803, September 2022.
      Previous studies suggested that dolphins perceive echo spectral features on coarse (macrospectrum) and fine (microspectrum) scales. This study was based on a finding that these auditory percepts are, to some degree, dependent on the dolphin's ∼250-μs auditory temporal window (i.e., “critical interval”). Here, two dolphins were trained to respond on passively detecting a simulated “target” echo complex [a pair of echo “highlights” with a characteristic 120-μs inter-highlight interval (IHI)]. This target had unique micro- and macrospectral features and was presented among “distractor” echoes with IHIs from 50 to 500 μs (i.e., microspectra) and various highlight durations (i.e., macrospectra). Following acquisition of this discrimination task, probe echo complexes with the macrospectrum of the target but IHIs matching the distractors were infrequently presented. Both dolphins initially responded more often to probes with IHIs of 80–200 μs. Response strategies diverged with increasing probe presentations; one dolphin responded to a progressively narrower range of probe IHIs while the second increased response rates for probes with IHIs> 250 μs. These results support previous conclusions that perception of macrospectra for complex echoes is nonconstant as the IHI decreases below ∼100 μs, but results approaching and exceeding 250 μs—the temporal window upper boundary—were more ambiguous.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-22T11:36:30Z
       
  • Feasibility evaluation of transtympanic laser stimulation of the cochlea
           from the outer ear

    • Free pre-print version: Loading...

      Authors: Miku Uenaka, Hidekazu Nagamura, Aya Okamoto, Shizuko Hiryu, Kohta I. Kobayasi, Yuta Tamai
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1850-1855, September 2022.
      Infrared laser stimulation has been studied as an alternative approach to auditory prostheses. This study evaluated the feasibility of infrared laser stimulation of the cochlea from the outer ear, bypassing the middle ear function. An optic fiber was inserted into the ear canal, and a laser was used to irradiate the cochlea through the tympanic membrane in Mongolian gerbils. A pulsed infrared laser (6.9 mJ/cm2) and clicking sound (70 peak-to-peak equivalent sound pressure level) were presented to the animals. The amplitude of the laser-evoked cochlear response was systematically decreased following insertion of a filter between the tympanic membrane and cochlea; however, the auditory-evoked cochlear response did not decrease. The filter was removed, and the laser-evoked response returned to around the original level. The amplitude ratio and the relative change in response amplitude before and during filter insertion significantly decreased as the absorbance of the infrared filter increased. These results indicate that laser irradiation could bypass the function of the middle ear and directly activate the cochlea. Therefore, laser irradiation from the outer ear is a possible alternative for stimulating the cochlea, circumventing the middle ear.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-22T11:36:29Z
       
  • Harmonics-to-noise ratio estimation with deterministically time-varying
           harmonic model for pathological voice signals

    • Free pre-print version: Loading...

      Authors: Takeshi Ikuma, Brad Story, Andrew J. McWhorter, Lacey Adkins, Melda Kunduk
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1783-1794, September 2022.
      The harmonics-to-noise ratio (HNR) and other spectral noise parameters are important in clinical objective voice assessment as they could indicate the presence of nonharmonic phenomena, which are tied to the perception of hoarseness or breathiness. Existing HNR estimators are built on the voice signals to be nearly periodic (fixed over a short period), although voice pathology could induce involuntary slow modulation to void this assumption. This paper proposes the use of a deterministically time-varying harmonic model to improve the HNR measurements. To estimate the time-varying model, a two-stage iterative least squares algorithm is proposed to reduce model overfitting. The efficacy of the proposed HNR estimator is demonstrated with synthetic signals, simulated tremor signals, and recorded acoustic signals. Results indicate that the proposed algorithm can produce consistent HNR measures as the extent and rate of tremor are varied.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-21T02:59:22Z
       
  • Acoustically driven orientation and navigation in enclosed spaces

    • Free pre-print version: Loading...

      Authors: Henning Steffens, Michael Schutte, Stephan D. Ewert
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1767-1782, September 2022.
      Awareness of space, and subsequent orientation and navigation in rooms, is dominated by the visual system. However, humans are able to extract auditory information about their surroundings from early reflections and reverberation in enclosed spaces. To better understand orientation and navigation based on acoustic cues only, three virtual corridor layouts (I-, U-, and Z-shaped) were presented using real-time virtual acoustics in a three-dimensional 86-channel loudspeaker array. Participants were seated on a rotating chair in the center of the loudspeaker array and navigated using real rotation and virtual locomotion by “teleporting” in steps on a grid in the invisible environment. A head mounted display showed control elements and the environment in a visual reference condition. Acoustical information about the environment originated from a virtual sound source at the collision point of a virtual ray with the boundaries. In different control modes, the ray was cast either in view or hand direction or in a rotating, “radar”-like fashion in 90° steps to all sides. Time to complete, number of collisions, and movement patterns were evaluated. Navigation and orientation were possible based on the direct sound with little effect of room acoustics and control mode. Underlying acoustic cues were analyzed using an auditory model.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-21T02:59:21Z
       
  • Under-resourced dialect identification in Ao using source information

    • Free pre-print version: Loading...

      Authors: Moakala Tzudir, Shikha Baghel, Priyankoo Sarmah, S. R. Mahadeva Prasanna
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1755-1766, September 2022.
      This paper reports the findings of an automatic dialect identification (DID) task conducted on Ao speech data using source features. Considering that Ao is a tone language, in this study for DID, the gammatonegram of the linear prediction residual is proposed as a feature. As Ao is an under-resourced language, data augmentation was carried out to increase the size of the speech corpus. The results showed that data augmentation improved DID by 14%. A perception test conducted on Ao speakers showed better DID by the subjects when utterance duration was 3 s. Accordingly, automatic DID was conducted on utterances of various duration. A baseline DID system with the Slms feature attained an average F1-score of 53.84% in a 3 s long utterance. Inclusion of source features, Silpr and [math], improved the F1-score to 60.69%. In a final system, with a combination of Silpr, [math], Slms, and Mel frequency cepstral coefficient features, the F1-score increased to 61.46%.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-20T02:46:13Z
       
  • Telehealth solutions for assessing auditory outcomes related to noise and
           ototoxic exposures in clinic and research

    • Free pre-print version: Loading...

      Authors: Samantha Kleindienst Robler, Laura Coco, Mark Krumm
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1737-1754, September 2022.
      Nearly 1.5 billion people globally have some decline in hearing ability throughout their lifetime. Many causes for hearing loss are preventable, such as that from exposure to noise and chemicals. According to the World Health Organization, nearly 50% of individuals 12–25 years old are at risk of hearing loss due to recreational noise exposure. In the occupational setting, an estimated 16% of disabling hearing loss is related to occupational noise exposure, highest in developing countries. Ototoxicity is another cause of acquired hearing loss. Audiologic assessment is essential for monitoring hearing health and for the diagnosis and management of hearing loss and related disorders (e.g., tinnitus). However, 44% of the world's population is considered rural and, consequently, lacks access to quality hearing healthcare. Therefore, serving individuals living in rural and under-resourced areas requires creative solutions. Conducting hearing assessments via telehealth is one such solution. Telehealth can be used in a variety of contexts, including noise and ototoxic exposure monitoring, field testing in rural and low-resource settings, and evaluating auditory outcomes in large-scale clinical trials. This overview summarizes current telehealth applications and practices for the audiometric assessment, identification, and monitoring of hearing loss.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-20T02:45:17Z
       
  • Sequential sensor selection for the localization of acoustic sources by
           sparse Bayesian learning

    • Free pre-print version: Loading...

      Authors: Milan Courcoux-Caro, Charles Vanwynsberghe, Cédric Herzet, Alexandre Baussard
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1695-1708, September 2022.
      This paper deals with the design of sensor arrays in the context involving the localization of a few acoustic sources. Sparse approximation is known to be effective to find the source locations, but it depends on different array characteristics, such as the number of sensors and the array geometry. The present paper tackles this array design problem under the form of a sequential sensor selection procedure. The proposed method alternates between two steps. One step involves a source localization estimator, given a current set of measurement points, to obtain the estimation variance. Then, the other step selects the new point where a future measurement will maximally decrease the variance from the previous step. As such, the procedure can be applied online. Both numerical and experimental studies are conducted in an indoor nearfield configuration. Results show that the proposed approach performs better than offline state-of-the-art methods, and the presented empirical study reveals a better robustness to the model mismatches originating from the room reflections.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-19T12:24:30Z
       
  • Auditory motion as a cue for source segregation and selection in a
           “cocktail party” listening environment

    • Free pre-print version: Loading...

      Authors: Adrian Y. Cho, Gerald Kidd
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1684-1694, September 2022.
      Source motion was examined as a cue for segregating concurrent speech or noise sources. In two different headphone-based tasks—motion detection (MD) and speech-on-speech masking (SI)—one source among three was designated as the target only by imposing sinusoidal variation in azimuth during the stimulus presentation. For MD, the lstener was asked which of the three concurrent sources was in motion during the trial. For SI, the listener was asked to report the words spoken by the moving speech source. MD performance improved as the amplitude of the sinusoidal motion (i.e., displacement in azimuth) increased over the range of values tested (±5° to ±30°) for both modulated noise and speech targets, with better performance found for speech. SI performance also improved as the amplitude of target motion increased. Furthermore, SI performance improved as word position progressed throughout the sentence. Performance on the MD task was correlated with performance on SI task across individual subjects. For the SI conditions tested here, these findings are consistent with the proposition that listeners first detect the moving target source, then focus attention on the target location as the target sentence unfolds.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-19T12:24:27Z
       
  • Implementation of continuously steerable beam patterns for a uniform
           circular projector array

    • Free pre-print version: Loading...

      Authors: Qiumu Wang, Yu Lan, Jun Fan
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1709-1720, September 2022.
      A continuously steerable super-cardioid beam pattern (SCBP) has advantages such as controllable direction, narrower beam width, and higher gain. It is generally implemented with a uniform circular array (UCA). Here, an implementation method of continuously steerable SCBPs is proposed for a projector array. The synthesis and the implementation of the continuously steerable SCBP are studied and analyzed based on a UCA model composed of omnidirectional sources. An improved version of the common method is proposed. It requires fewer array elements and the massive power amplifiers matched to each array element, which reduces the cost and the installation space. Subsequently, a continuously steerable SCBP is implemented with a uniform circular projector array (UCPA). This system is composed of single-sided radiation flextensional transducers and is studied and analyzed with a finite element method, which verified that the proposed method is suitable for the underwater acoustic projector array. Finally, UCPA prototypes were fabricated. The tests demonstrated that the proposed implementation method is a flexible way for the application of the continuously steerable SCBP in the low-frequency emission field.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-19T12:24:25Z
       
  • Analysis of phase derivatives of speech signals

    • Free pre-print version: Loading...

      Authors: B. Yegnanarayana
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1721-1736, September 2022.
      This paper examines the phase derivatives of speech signals. The instantaneous complex spectra obtained in the single frequency filtering (SFF) analysis of signals is used to derive the phase function. The problem of phase wrapping is avoided by using the proposed modification to SFF analysis to derive a scaled down version of the phase function. We consider the derivatives of the exponent (i.e., logarithm) of the complex SFF spectra, with respect to frequency, time, and both frequency and time. The imaginary part of the exponent is the phase function, and the real part is the log magnitude function. The negative derivative of phase with respect to frequency is the group delay (GD) function, and the derivative of the phase with respect to time is the instantaneous frequency (IF) function. The features of speech production displayed through the GD function are compared with the features displayed through the derivative with respect to frequency of the corresponding log magnitude function. Likewise, the features of production displayed through the IF function are compared with the features displayed through the derivative with respect to time of the corresponding log magnitude function. The speech production characteristics reflected in these representations of phase derivatives are examined for different types of utterances.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-19T12:24:24Z
       
  • An additional source of distortion-product otoacoustic emissions from
           perturbation of nonlinear force by reflection from inhomogeneities

    • Free pre-print version: Loading...

      Authors: Aleš Vetešník, Václav Vencovský, Anthony W. Gummer
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1660-1682, September 2022.
      The basilar membrane in the cochlea can be modeled as an array of fluid coupled segments driven by stapes vibration and by the undamping nonlinear force simulating cochlear amplification. If stimulated with two tones, the model generates additional tones due to nonlinear distortion. These distortion products (DPs) can be transmitted into the ear canal and produce distortion-product otoacoustic emissions (DPOAEs) known to be generated in the healthy ear of various vertebrates. This study presents a solution for DPs in a two-dimensional nonlinear cochlear model with cochlear roughness—small irregularities in the impedance along the basilar membrane, which may produce additional DPs due to coherent reflection. The solution allows for decomposition of various sources of DPs in the model. In addition to the already described nonlinear-distortion and coherent-reflection mechanisms of DP generation, this study identifies a long-latency DPOAE component due to perturbation of nonlinear force. DP wavelets that are coherently reflected due to impedance irregularities travel toward the stapes across the primary generation region of DPs and there evoke perturbation of the nonlinear undamping force. The ensuing DP wavelets have opposite phase to the wavelets arising from coherent reflection, which results in partial cancellation of the coherent-reflection DP wavelets.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-16T11:36:56Z
       
  • Erratum: Accounting for the Lombard effect in estimating the probability
           of detection in passive acoustic surveys: Applications for single sensor
           mitigation and monitoring [J. Acoust. Soc. Am. 151(1), 67–79 (2022)]

    • Free pre-print version: Loading...

      Authors: K. J. Palmer, Gi-Mick Wu, Christopher Clark, Holger Klinck
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1683-1683, September 2022.

      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-16T11:36:55Z
       
  • An automated framework for long-range acoustic positioning of autonomous
           underwater vehicles

    • Free pre-print version: Loading...

      Authors: Cristian Graupe, Lora J. Van Uffelen, Peter F. Worcester, Matthew A. Dzieciuch, Bruce M. Howe
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1615-1626, September 2022.
      An automated method was developed to align underwater acoustic receptions at various depths and ranges to a single reference prediction of long range acoustic arrival structure as it evolves with range in order to determine source-receiver range. Acoustic receptions collected by four autonomous underwater vehicles deployed in the Philippine Sea as part of an ocean acoustic propagation experiment were used to demonstrate the method. The arrivals were measured in the upper 1000 m of the ocean at ranges up to 700 km from five moored, low frequency broadband acoustic tomography sources. Acoustic arrival time structure for pulse compressed signals at long ranges is relatively stable, yet real ocean variability presents challenges in acoustic arrival matching. The automated method takes advantage of simple projections of the measured structure onto the model space that represents all possible pairings of measured peaks to predicted eigenrays and minimizes the average travel-time offset across selected pairings. Compared to ranging results obtained by manual acoustic arrival matching, 93% of the automatically-obtained range estimates were within 75 m of the manually-obtained range estimates. Least squares residuals from positioning estimates using the automatically-obtained ranges with a fault detection scheme were 55 m root-mean-square.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-13T11:14:23Z
       
  • On the use of the TIMIT, QuickSIN, NU-6, and other widely used bandlimited
           speech materials for speech perception experiments

    • Free pre-print version: Loading...

      Authors: Brian B. Monson, Emily Buss
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1639-1645, September 2022.
      The use of spectrally degraded speech signals deprives listeners of acoustic information that is useful for speech perception. Several popular speech corpora, recorded decades ago, have spectral degradations, including limited extended high-frequency (EHF) (>8 kHz) content. Although frequency content above 8 kHz is often assumed to play little or no role in speech perception, recent research suggests that EHF content in speech can have a significant beneficial impact on speech perception under a wide range of natural listening conditions. This paper provides an analysis of the spectral content of popular speech corpora used for speech perception research to highlight the potential shortcomings of using bandlimited speech materials. Two corpora analyzed here, the TIMIT and NU-6, have substantial low-frequency spectral degradation (
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-13T11:14:21Z
       
  • Predicting transmission loss in underwater acoustics using convolutional
           recurrent autoencoder network

    • Free pre-print version: Loading...

      Authors: Wrik Mallik, Rajeev K. Jaiman, Jasmin Jelovica
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1627-1638, September 2022.
      Underwater noise transmission in the ocean environment is a complex physical phenomenon involving not only widely varying physical parameters and dynamical scales but also uncertainties in the ocean parameters. It is challenging to construct generalized physical models that can predict transmission loss in a broad range of situations. In this regard, we propose a convolutional recurrent autoencoder network (CRAN) architecture, which is a data-driven deep learning model for learning far-field acoustic propagation. Being data-driven, the CRAN model relies only on the quality of the data and is agnostic to how the data are obtained. The CRAN model can learn a reduced-dimensional representation of physical data and can predict the far-field acoustic signal transmission loss distribution in the ocean environment. We demonstrate the ability of the CRAN model to learn far-field transmission loss distribution in a two-dimensional ocean domain with depth-dependent sources. Results show that the CRAN can learn the essential physical elements of acoustic signal transmission loss generated due to geometric spreading, refraction, and reflection from the ocean surface and bottom. Such ability of the CRAN to learn complex ocean acoustics transmission has the potential for real-time far-field underwater noise prediction for marine vessel decision-making and online control.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-13T11:14:20Z
       
  • A basic protocol for the acoustic characterization of small and
           medium-sized classrooms

    • Free pre-print version: Loading...

      Authors: Arianna Astolfi, Greta Minelli, Giuseppina Emma Puglisi
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1646-1659, September 2022.
      To promote a fast and effective characterization of the sound environment in small and medium-sized classrooms, a basic measurement protocol, based on a minimum number of parameters and positions, is provided. Measurements were taken in 29 occupied classrooms belonging to 13 primary schools in Turin, Italy, that differ in location and typology. The background noise level was acquired during silent and group activities, and the reverberation time, speech clarity, useful-to-detrimental ratio and speech level, were acquired along the main axis of each classroom and in one or two offset positions. To reduce the number of measured parameters that can be used to fully characterize classroom acoustics, data were divided into two groups on the basis of a cutoff value of maximum occupied reverberation time in the case of moderate and severe requirements. Given the strong correlation among the quantities, thresholds were identified for the other acoustical parameters, and their accuracy and precision were tested to assess their ability to classify the acoustic quality as compliant or non-compliant. Results suggest that more convenient parameters, like clarity in the central position of the classroom, can be used instead of reverberation time to classify classroom acoustics.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-13T11:14:17Z
       
  • The importance of sound to the Atlantic cod, Gadus morhua, and the
           Atlantic haddock, Melanogrammus aeglefinus

    • Free pre-print version: Loading...

      Authors: Anthony Hawkins
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1605-1614, September 2022.
      The gadoid fishes, including the Atlantic cod and haddock, are currently being exploited close to their safe biological limits, requiring restrictions upon the human activities that may harm them. This has prompted interest in the biology of such fishes. Studies of the cod and haddock have shown highly complex behavior, involving prolonged and energetic visual and acoustic displays. Different sounds are produced in different behavioral contexts and are emitted almost continuously by cod and haddock, especially throughout the spawning season (February to May). The distinctive characteristics of these sounds make it possible to locate spawning cod and haddock at their marine spawning grounds. Human activities in these areas may affect their spawning adversely and have deleterious effects upon their stocks. Man-made sounds in water do have an adverse effect upon cod and haddock, and other fishes. Listening for the cod and haddock sounds provides a reliable, non-invasive technique for detecting their locations, and especially their spawning areas, and enables them to be protected well.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-12T12:04:32Z
       
  • A simple model for elastic wave propagation in hard sphere-filled random
           composites

    • Free pre-print version: Loading...

      Authors: C. Q. Ru
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1595-1604, September 2022.
      A simple model is proposed to study wave propagation in hard sphere-reinforced elastic random composites. Compared to existing related models, the proposed model is featured by a modified form of classical elastodynamic equations in which the inertia term is substituted by the acceleration field of the mass centre of a representative unit cell, supplied with a derived simple differential relation between the displacement field of the composite and the displacement field of the mass centre of a representative unit cell. The present model enjoys conceptual and mathematical simplicity although it is restricted to hard sphere-filled elastic composites in which the elastic moduli of embedded spheres are much (at least 4–5 times) stiffer than those of a softer matrix. Explicit formulas are derived for the attenuation coefficient and the effective phase velocity of plane longitudinal P-waves and transverse S-waves. The efficiency and reasonable accuracy of the present model are demonstrated by reasonably good agreement between the predicted results and some established known data. The proposed model could offer a potential general method to study various three-dimensional dynamic problems of hard sphere-filled elastic random composites.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-09T11:59:23Z
       
  • Is speech intelligibility what speech intelligibility tests test'

    • Free pre-print version: Loading...

      Authors: Timothy Beechey
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1573-1585, September 2022.
      Natural, conversational speech signals contain sources of symbolic and iconic information, both of which are necessary for the full understanding of speech. But speech intelligibility tests, which are generally derived from written language, present only symbolic information sources, including lexical semantics and syntactic structures. Speech intelligibility tests exclude almost all sources of information about talkers, including their communicative intentions and their cognitive states and processes. There is no reason to suspect that either hearing impairment or noise selectively affect perception of only symbolic information. We must therefore conclude that diagnosis of good or poor speech intelligibility on the basis of standard speech tests is based on measurement of only a fraction of the task of speech perception. This paper presents a descriptive comparison of information sources present in three widely used speech intelligibility tests and spontaneous, conversational speech elicited using a referential communication task. The aim of this comparison is to draw attention to the differences in not just the signals, but the tasks of listeners perceiving these different speech signals and to highlight the implications of these differences for the interpretation and generalizability of speech intelligibility test results.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-09T11:59:22Z
       
  • Auditory spatial analysis in reverberant multi-talker environments with
           congruent and incongruent audio-visual room information

    • Free pre-print version: Loading...

      Authors: Axel Ahrens, Kasper Duemose Lund
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1586-1594, September 2022.
      In a multi-talker situation, listeners have the challenge of identifying a target speech source out of a mixture of interfering background noises. In the current study, it was investigated how listeners analyze audio-visual scenes with varying complexity in terms of number of talkers and reverberation. The visual information of the room was either congruent with the acoustic room or incongruent. The listeners' task was to locate an ongoing speech source in a mixture of other speech sources. The three-dimensional audio-visual scenarios were presented using a loudspeaker array and virtual reality glasses. It was shown that room reverberation, as well as the number of talkers in a scene, influence the ability to analyze an auditory scene in terms of accuracy and response time. Incongruent visual information of the room did not affect this ability. When few talkers were presented simultaneously, listeners were able to detect a target talker quickly and accurately even in adverse room acoustical conditions. Reverberation started to affect the response time when four or more talkers were presented. The number of talkers became a significant factor for five or more simultaneous talkers.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-09T11:59:20Z
       
  • The impact of the COVID-19 outbreak on the air traffic noise at the
           Hannover airport region

    • Free pre-print version: Loading...

      Authors: Gil Felix Greco, Shreyas Mysore Guruprasad, Tobias P. Ring, Sabine C. Langer
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1564-1572, September 2022.
      In this work, the impact of the COVID-19 outbreak on the environmental noise generated by the air traffic at the Hannover Airport, Germany, is assessed. For this purpose, a comparative study of the air traffic noise in the years 2019 and 2020 is conducted by means of publicly available measurement data and computational simulations. Based on environmental noise directives defined by the responsible German authorities, the comparative study is conducted in terms of A-weighted equivalent sound pressure level metrics computed for the six months of the forecast years with the largest number of flights. In comparison with the year of 2019, the measurement data indicates that the [math], and [math] were reduced in average by 2.4, 4.2, and 3.7 dBA, respectively, in the year 2020. Furthermore, the results based on the computational simulations show that the isocontour areas of the [math] and [math] noise protection zones defined by the German federal government were reduced by [math] and [math], respectively, in the year of 2020.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-09T11:59:18Z
       
  • The effect of hearing protection worn by talker and/or target listener on
           speech production in quiet and noise

    • Free pre-print version: Loading...

      Authors: Ghazaleh Vaziri, Christian Giguère, Hilmi R. Dajani
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1528-1538, September 2022.
      Speech production while wearing hearing protectors poses significant challenges due to their occlusion effect and disruption of the Lombard effect. An experiment was conducted with 24 individuals as they read a list of 12 sentences in open ears and while wearing an earmuff in quiet and in four different noises [pink, International Female Fluctuating Masker (IFFM), speech-spectrum noise (SSnoise), and helicopter] at two levels (70 and 85 dBA). An acoustic manikin, fitted or not with an identical protector, served as the target listener. In noise, speech levels decreased when the talkers wore the earmuff but increased when the target listener was fitted with the earmuff. When the earmuff was used by both the talkers and target listener, speech levels were lower by 3–6 dB at the higher noise level compared to when they were both open ears. Speech levels were typically lower, but extended speech intelligibility index estimates were consistently higher, in fluctuating (IFFM, helicopter) than in continuous noises (pink, SSnoise). Talkers' pitch frequency and voice spectrum measurements followed very closely the changes in speech levels, showing no evidence of compensatory voice modifications. Implications of the lower talker speech levels when wearing hearing protectors are discussed in terms of protector selection, training, and individuals with hearing loss.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-08T12:27:53Z
       
  • Mechanical and vibro-acoustic performance of sandwich panel with
           perforated honeycomb cores

    • Free pre-print version: Loading...

      Authors: Ludi Kang, Bilong Liu, Fengyan An, Dapeng Wei
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1539-1546, September 2022.
      The effect of perforating the honeycomb walls of a honeycomb sandwich panel on the dynamic bending stiffness and sound transmission loss of the panel is investigated. The dynamic bending stiffness and sound transmission loss of several sandwich panels with different cores are calculated using a semi-analytical method, and the static bending stiffness and flatwise stiffness of these structures are also analyzed with the finite element method. Furthermore, the influences of the honeycomb shape, the hole shape of the perforated honeycomb wall, the number of perforations, and the wall thickness on the vibro-acoustic and mechanical properties of the sandwich panel are investigated. The results show that the static mechanical performance of the sandwich panel quickly reaches a high level when the ratio of honeycomb wall thickness to length t/l is about 5.3 × 10−3 and a square hole in the honeycomb wall can bring superior characteristics of “high static and low dynamic properties,” significantly improving the sound insulation of the sandwich panel. This study makes an effective reference for the optimized design of the innovative sandwich structure in practical applications.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-08T12:27:52Z
       
  • Modelling and visualization for the analysis and comprehension of the
           acoustic performance of buildings through the implementation of a building
           information modelling–based methodology

    • Free pre-print version: Loading...

      Authors: María L. de la Hoz-Torres, Antonio J. Aguilar, M. Dolores Martínez-Aires, Diego P. Ruiz
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1515-1527, September 2022.
      Technical and technological advances have revolutionised the architecture, engineering, and construction industries in recent decades. Building information modelling (BIM) methodology has become essential in the process of information management and the development of building projects. This study aims to analyse the potential advantages of the implementation of BIM-based models for the acquisition of theoretical and procedural knowledge about building acoustics. This procedure was implemented as part of a problem-solving exercise in Science, Technology, Engineering, and Mathematics (STEM) university degrees. For this purpose, three-dimensional (3D) BIM models were generated to assess the contribution of their implementation in the process of visualization, comprehension, and analysis of the acoustic behaviour of buildings. The participants' experiences and satisfaction with the BIM models were measured through a questionnaire. The results showed a high level of satisfaction among the participants and good potential for the application of 3D models based on BIM methodology for the acquisition of knowledge and practical skills in building acoustics. These results highlight the potential of BIM models to provide information for understanding the procedure followed during data collection in the experimental analysis and to facilitate the understanding of system behavior.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-08T12:27:52Z
       
  • A functional regression analysis of vessel source level measurements from
           the Enhancing Cetacean Habitat and Observation (ECHO) database

    • Free pre-print version: Loading...

      Authors: Alexander O. MacGillivray, Laurie M. Ainsworth, Joanna Zhao, Joshua N. Dolman, David E. Hannay, Héloïse Frouin-Mouy, Krista B. Trounce, Derek A. White
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1547-1563, September 2022.
      Measurements of the source levels of 9880 passes of 3188 different large commercial ships from the Enhancing Cetacean Habitat and Observation (ECHO) program database were used to investigate the dependencies of vessel underwater noise emissions on several vessel design parameters and operating conditions. Trends in the dataset were analyzed using functional regression analysis, which is an extension of standard regression analysis and represents a response variable (decidecade band source level) as a continuous function of a predictor variable (frequency). The statistical model was applied to source level data for six vessel categories: cruise ships, container ships, bulk carriers, tankers, tugs, and vehicle carriers. Depending on the frequency band and category, the functional regression model explained approximately 25%–50% of the variance in the ECHO dataset. The two main operational parameters, speed through water and actual draft, were the predictors most strongly correlated with source levels in all of the vessel categories. Vessel size (represented via length overall) was the design parameter with the strongest correlation to underwater radiated noise for three categories of vessels (bulkers, containers, and tankers). Other design parameters that were investigated (engine revolutions per minute, engine power, design speed, and vessel age) had weaker but nonetheless significant correlations with source levels.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-08T12:27:50Z
       
  • Leaky wave characterisation using spectral methods

    • Free pre-print version: Loading...

      Authors: Evripides Georgiades, Michael J. S. Lowe, Richard V. Craster
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1487-1497, September 2022.
      Leaky waves are an important class of waves, particularly for guiding waves along structures embedded within another medium; a mismatch in wavespeeds often leads to leakage of energy from the waveguide, or interface, into the medium, which consequently attenuates the guided wave. The accurate and efficient identification of theoretical solutions for leaky waves is a key requirement for the choices of modes and frequencies required for non-destructive evaluation inspection techniques. We choose a typical situation to study: an elastic waveguide with a fluid on either side. Historically, leaky waves are identified via root-finding methods that have issues with conditioning, or numerical methods that struggle with the exponential growth of solutions at infinity. By building upon a spectral collocation method, we show how it can be adjusted to find exponentially growing solutions, i.e., leaky waves, leading to an accurate, fast, and efficient identification of their dispersion properties. The key concept required is a mapping, in the fluid region, that allows for exponential growth of the physical solution at infinity, whilst the mapped numerical setting decays. We illustrate this by studying leaky Lamb waves in an elastic waveguide immersed between two different fluids and verify this using the commercially available software disperse.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-07T12:35:46Z
       
  • Acoustic computing: At tunable pseudospin-1 Hermitian Dirac-like cone

    • Free pre-print version: Loading...

      Authors: Mustahseen M. Indaleeb, Hossain Ahmed, Sourav Banerjee
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1449-1462, September 2022.
      Hermitian Dirac-like cones are proposed for creating acoustic logic gates herein. The predictive phenomenon of creating Dirac-like cones near a bipolar antisymmetric deaf band was found to be useful for acoustic computing of Boolean algebra. Unlike previous approaches, Dirac-like cone creates exclusive opportunity to perform all possible Boolean algebra computation with valid inputs. The phenomenon is demonstrated in two-dimensional phononic crystals (PnCs), consisting of tunable square columns in air media. By predictive tuning of the deaf bands, a triply to doubly degenerated Dirac-like cone is reported to form and is particularly useful for acoustic computing. It is only possible when a bottom band has a negative curvature that is lifted from a nearby doubly degenerated band with positive curvature, which is again degenerated with a deaf band. On the contrary, similar computing possibilities are difficult when the bottom band degenerates with the deaf band and the top band is lifted. Using these phenomena, acoustic logic gates are designed to perform Boolean algebra through AND, NAND, OR, and NOR gate operations. A simple one degree of freedom system and a complex six degrees of freedom system are proposed and demonstrated in which simple rotation of the PnCs activates a specific gate.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-07T12:35:45Z
       
  • Acoustic correlates and listener ratings of function word reduction in
           child versus adult speech

    • Free pre-print version: Loading...

      Authors: Melissa A. Redford, Phil J. Howson
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1463-1475, September 2022.
      The present study investigated “the” reduction in phrase-medial Verb-the-Noun sequences elicited from 5-year-old children and young adults (18–22 yr). Several measures of reduction were calculated based on acoustic measurement of these sequences. Analyses on the measures indicated that the determiner vowel was reduced in both child and adult speech relative to content word vowels, but it was reduced less in child speech compared to adult speech. Listener ratings on the sequences indicated a preference for adult speech over children's speech. Acoustic measures of reduction also predicted goodness ratings. Listeners preferred sequences with shorter and lower amplitude determiner vowels relative to content word vowels. They also preferred a more neutral schwa over more coarticulated versions. In sequences where ratings differed by age group, the effect of coarticulation was limited to adult speech and the effect of relative schwa duration was limited to child speech. The results are discussed with reference to communicative pressures on speech, including the rhythmic and semantic pressures towards reduction versus the pressure to convey adequate information in the acoustic signal. It is argued that these competing pressures on production may delay the acquisition of adult-like function word reduction.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-07T12:35:44Z
       
  • Pseudo-equivalent deterministic excitation method application for
           experimental reproduction of a structural response to a turbulent boundary
           layer excitation

    • Free pre-print version: Loading...

      Authors: G. Mazzeo, M. Ichchou, G. Petrone, O. Bareille, S. De Rosa, F. Franco
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1498-1514, September 2022.
      In the transportation engineering field, the turbulent boundary layer over a structure is one of the most relevant sources of structural vibration and emitted noise. Wind tunnels are still one of the best options for vibroacoustic experimental analyses for this specific problem. However, it is also true that this experimental method is not always affordable, due to several limitations—settings hard to control, time and money consumption, discrepancies among laboratories—that wind tunnel facilities present. It has already developed different methodologies to address this necessity, most of them based on the use of loudspeakers or shakers. In this work, an existing numerical method, called the pseudo-equivalent deterministic excitation method (PEDEM), is further developed for the experimental purpose of reproducing the experimental structural response of a panel subjected to a turbulent boundary layer (TBL) excitation, by using an equivalent rain-on-the-roof excitation instead; different formulations are used for the application of this approximated TBL excitation. The experimental application of PEDEM, here called X-PEDEM, is validated by comparison with experimental results of two different panels analysed in two different wind tunnel facilities.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-07T12:35:40Z
       
  • Evaluating automatic creaky voice detection methods

    • Free pre-print version: Loading...

      Authors: Hannah White, Joshua Penney, Andy Gibson, Anita Szakay, Felicity Cox
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1476-1486, September 2022.
      There is growing interest in research on the non-modal voice quality, creaky voice; however, its identification often relies on time-consuming manual annotation, leading to a recent focus on automatic creak detection methods. Various automatic methods have been proposed, which rely on varying types and combinations of acoustic cues for creak detection. In this paper, we compare the performance of three automatic tools, the AntiMode method, the Creak Detector algorithm, and the Roughness algorithm, against manual annotation of creak using data from 80 Australian English speakers. We explore the possibility that tools used in combination may yield more accurate creak detection than individual tools used alone. Based on method comparisons, we present options for researchers, including an “out-of-the-box” approach, which supports combining automatic tools, and propose additional steps to further improve creak detection. We found restricting analysis to sonorant segments significantly improves automatic creak detection, and tools performed consistently better on female speech than male speech. Findings support previous work showing detection may be optimised by performing a creak probability threshold sweep on a subset of data prior to applying the Creak Detector algorithm on new datasets. Results provide promising solutions for advancing efficient large-scale research on creaky voice.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-07T12:35:37Z
       
  • Error detection and filtering of incompressible flow simulations for
           aeroacoustic predictions of human voice

    • Free pre-print version: Loading...

      Authors: Stefan Schoder, Florian Kraxberger, Sebastian Falk, Andreas Wurzinger, Klaus Roppert, Stefan Kniesburges, Michael Döllinger, Manfred Kaltenbacher
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1425-1436, September 2022.
      The presented filtering technique is proposed to detect errors and correct outliers inside the acoustic sources, respectively, the first time derivative of the incompressible pressure obtained from large eddy simulations with prescribed vocal fold motion using overlay mesh methods. Regarding the perturbed convective wave equation, the time derivative of the incompressible pressure is the primary sound source in the human phonation process. However, the incompressible pressure can be erroneous and have outliers when fulfilling the divergence-free constraint of the velocity field. This error is primarily occurring for non-conserving prescribed vocal fold motions. Therefore, the method based on a continuous stationary random process was designed to detect rare events in the time derivative of the pressure. The detected events are then localized and treated by a defined window function to increase their probability. As a consequence, the data quality of the non-linearly filtered data is enhanced significantly. Furthermore, the proposed method can also be used to assess convergence of the aeroacoustic source terms, and detect regions and time intervals, which show a non-converging behavior by an impulse-like structure.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-06T01:21:34Z
       
  • A lumped parameter model of the longitudinal NiMnGa transducer based on
           piezomagnetic equations

    • Free pre-print version: Loading...

      Authors: Yu Lan, Houqi Wang, Wei Lu, Hao Sun
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1416-1424, September 2022.
      The NiMnGa alloy is a typical magnetic shape memory alloy with up to 6% immense strain, high energy density, and low effective elastic modulus. These comprehensive characteristics make it possible to realize a low-frequency underwater acoustic transducer. To describe the field-induced dynamic strain, an equivalent circuit model (ECM) of a longitudinal NiMnGa transducer is presented as a lumped parameter model, which couples magnetics, mechanics, and acoustics. In this paper, we focus on the piezomagnetic equations as the constitutive relationship of the NiMnGa element with a dynamic magnetic field. Furthermore, combined with the dynamic kinetic equation, the equivalent circuit is derived, and it has the advantage of containing acoustical terminals. The proposed model can predict the resonance frequency, effective stiffness, and input impedance of the NiMnGa transducer. Finally, a finite element model (FEM) is developed to verify the lumped parameter model. The results indicate that the spring's stiffness increases the resonance frequency, while the mass load is on the contrary, and they both agree well with the results of ECM. In addition, the FEM and ECM can also predict the dynamic responses, which provide a guideline for the design of longitudinal NiMnGa transducers.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-06T01:21:34Z
       
  • Evaluation of binomial distribution estimates of confidence intervals of
           speech-recognition test scores

    • Free pre-print version: Loading...

      Authors: Robert H. Margolis, Richard H. Wilson
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1404-1415, September 2022.
      Speech-recognition tests are a routine component of the clinical hearing evaluation. The most common type of test uses recorded monosyllabic words presented in quiet. The interpretation of test scores relies on an understanding of the variance of repeated tests. Confidence intervals are useful for determining if two scores are significantly different or if the difference is due to the variability of test scores. Because the response to each test item is binary, either correct or incorrect, the binomial distribution has been used to estimate confidence intervals. This method requires that test scores be independent. If the scores are not independent, the binomial distribution will not accurately estimate the variance of repeated scores. A previously published dataset with repeated scores from normal-hearing and hearing-impaired listeners was used to derive confidence intervals from actual test scores in contrast to the predicted confidence intervals in earlier reports. This analysis indicates that confidence intervals predicted by the binomial distribution substantially overestimate the variance of repeated scores resulting in erroneously broad confidence intervals. High correlations were found for repeated scores, indicating that scores are not independent. The interdependence of repeated scores invalidates confidence intervals predicted by the binomial distribution. Confidence intervals and confidence levels for repeated measures were determined empirically from measured test scores to assist in interpreting differences between repeat scores.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-06T01:21:33Z
       
  • The effect of leading edge porosity on airfoil turbulence interaction
           noise

    • Free pre-print version: Loading...

      Authors: Luke Bowen, Alper Celik, Beckett Zhou, Michelle Fernandino Westin, Mahdi Azarpeyvand
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1437-1448, September 2022.
      Airfoil turbulence interaction noise and the flow field up to and over the porous leading edge is experimentally studied. The porous leading edges were of the same base triply periodic minimal surface structure with varying porosity to enable us to understand how the porosity, permeability, and pore size affect the generated turbulence interaction noise. The turbulent flow was generated by means of a passive turbulence grid that does not affect the normal background noise of the wind tunnel. Far-field noise results were obtained from a polar microphone array to assess the directivity of the sound as well as the narrowband frequency contributions. Far-field noise results demonstrate that increasing porosity reduces the turbulence interaction noise over low-to-mid frequencies, with a penalty of a high frequency noise increase. Flow measurement results indicate hydrodynamic penetration of the flow into the porous structure at the leading edge. Furthermore, the two-point correlation analysis of the velocity fluctuations approaching the leading edge shows that the turbulent structures approaching the solid leading edge appear to deform into more two-dimensional structures, whereas in the case of the porous leading edge, the turbulent structures appear to retain a strong spanwise coherence up to the point of hydrodynamic penetration.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-06T01:21:32Z
       
  • The sensitivity of bone conduction for dental implants

    • Free pre-print version: Loading...

      Authors: Fengxuan Ren, Yutong Li, Lidan Chen, Jiaqi Huang, Jianxiang Tao
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1389-1393, September 2022.
      Dental implants are connected to the alveolar bone by osseointegration. Dental implants could be used as a potential bone conduction (BC) hearing assistive device in the mouth. However, the BC threshold of dental implants has not been reported. The present study aimed to examine the pure tone auditory thresholds of normal human subjects to BC stimulation of the implants. Dental implants showed a significantly lower BC threshold than natural teeth and mastoids. Mandibular dental implants had BC sensitivity similar to that of maxillary dental implants. The BC threshold of anterior dental implants was significantly lower than that of posterior dental implants. Dental implants exhibited excellent BC properties.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-02T02:00:20Z
       
  • Adding noise is a confounded nuisance

    • Free pre-print version: Loading...

      Authors: Alexander L. Francis
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1375-1388, September 2022.
      A wide variety of research and clinical assessments involve presenting speech stimuli in the presence of some kind of noise. Here, I selectively review two theoretical perspectives and discuss ways in which these perspectives may help researchers understand the consequences for listeners of adding noise to a speech signal. I argue that adding noise changes more about the listening task than merely making the signal more difficult to perceive. To fully understand the effects of an added noise on speech perception, we must consider not just how much the noise affects task difficulty, but also how it affects all of the systems involved in understanding speech: increasing message uncertainty, modifying attentional demand, altering affective response, and changing motivation to perform the task.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-02T02:00:20Z
       
  • Modeling the effect of random roughness on synthetic aperture sonar image
           statistics

    • Free pre-print version: Loading...

      Authors: Anthony P. Lyons, Derek R. Olson, Roy E. Hansen
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1363-1374, September 2022.
      A model has been developed to predict the effect of random seafloor roughness on synthetic aperture sonar (SAS) image statistics, based on the composite roughness approximation–a physical scattering model. The continuous variation in scattering strength produced by a random slope field is treated as an intensity scaling on the image speckle produced by the coherent SAS imaging process. Changes in image statistics caused by roughness are quantified in terms of the scintillation index (SI). Factors influencing the SI include the seafloor slope variance, geo-acoustic properties of the seafloor, the probability density function describing the speckle, and the signal-to-noise ratio. Example model-data comparisons are shown for SAS images taken at three different sites using three different high-frequency SAS systems. Agreement between the modeled and measured SI show that it is possible to link range-dependent image statistics to measurable geo-acoustic properties, providing the foundation necessary for solving problems related to the detection of targets using high-frequency imaging sonars, including performance prediction or adaptation of automated detection algorithms. Additionally, this work illustrates the possible use of SAS systems for remote sensing of roughness parameters such as root mean square slope or height.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-02T02:00:17Z
       
  • Educational open source kit for the evaluation of acoustic leaky wave
           antennas with metamaterials

    • Free pre-print version: Loading...

      Authors: Eduardo Romero-Vivas, Javier Romero-Vivas, Omar Bustamante, Braulio Leon-Lopez
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1357-1362, September 2022.
      There is a growing interest in the field of acoustic metamaterials. These materials use periodic structures to exhibit properties not usually found in nature, such as negative mass or negative compressibility. The physics supporting these devices might seem counterintuitive at first, necessitating additional educational resources in this area. A leaky wave antenna (LWA) is a good example of a practical device that can be implemented as a standard material and a metamaterial. As the latter, the device extends its operational range, linking concepts related to both versions. This work presents an experimental open source kit designed for teaching the basic notions, including a computational routine for testing its analytical performance. The kit shown in this work has interchangeable units to experiment with several configurations (slit, axisymmetric, periodic hole, and membrane based metamaterial) and parameters of the antenna's design. The kit provides an opportunity to get hands-on experience on the real-life performance of LWAs, thanks to the use of low-cost materials, minimal equipment, and the practical nature of the antenna.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-02T02:00:12Z
       
  • Reconsidering commonly used stimuli in speech perception experiments

    • Free pre-print version: Loading...

      Authors: Matthew B. Winn, Richard A. Wright
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1394-1403, September 2022.
      This paper examines some commonly used stimuli in speech perception experiments and raises questions about their use, or about the interpretations of previous results. The takeaway messages are: 1) the Hillenbrand vowels represent a particular dialect rather than a gold standard, and English vowels contain spectral dynamics that have been largely underappreciated, 2) the /ɑ/ context is very common but not clearly superior as a context for testing consonant perception, 3) /ɑ/ is particularly problematic when testing voice-onset-time perception because it introduces strong confounds in the formant transitions, 4) /dɑ/ is grossly overrepresented in neurophysiological studies and yet is insufficient as a generalized proxy for “speech perception,” and 5) digit tests and matrix sentences including the coordinate response measure are systematically insensitive to important patterns in speech perception. Each of these stimulus sets and concepts is described with careful attention to their unique value and also cases where they might be misunderstood or over-interpreted.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-02T02:00:12Z
       
  • Effect of lockdown amid second wave of COVID-19 on environmental noise
           scenario of the megacity Delhi, India

    • Free pre-print version: Loading...

      Authors: S. Kumar, N. Garg, B. S. Chauhan, C. Gautam, T. Chand, M. P. George, K. S. Jayachandran
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1317-1336, September 2022.
      This paper analyzes the impact of second wave of COVID-19 lockdown on environmental noise levels of 25 sites in Delhi city and compares the noise scenario during pre-lockdown, lockdown, and post-lockdown periods. The study utilized the noise monitoring data acquired from 25 real-time ambient noise monitoring stations, installed by the Delhi Pollution Control Committee, Delhi, at various sites throughout Delhi city. A significant reduction of up to 10 and 3 dB(A) in day and night equivalent noise levels, respectively, had been observed during the lockdown period as compared to the pre-lockdown and post-lockdown periods. The study also revealed that only nine sites, including four industrial and five commercial zone sites, complied with the ambient noise standards during lockdown period, and no silence or residential zone sites complied with the ambient noise standards even during the lockdown period. A roadmap for environmental noise management and control is suggested. The study also reports the community's perception toward the change in acoustic environment of Delhi city during the lockdown period by conducting an environmental noise perception survey. The present study should be helpful in devising noise control action plans and policy interventions for environmental noise management and control in the metropolitan city Delhi, India.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-02T02:00:11Z
       
  • Radiation forces on highly reflecting circular cylinders in two slanted
           plane waves: Specular-reflection contributions

    • Free pre-print version: Loading...

      Authors: Philip L. Marston, Auberry R. Fortuner
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1337-1344, September 2022.
      Situations arise where it is desirable to understand and estimate the radiation force on large smooth highly reflecting objects in water illuminated by beams of ultrasound. The approach examined here is to extend a formulation experimentally confirmed by Herrey [J. Acoust. Soc. Am. 27, 891–896 (1955)] for tilted reflecting surfaces in fluids that are modeled as being inviscid. The formulation applies Brillouin's analysis of the Langevin-like radiation force on objects in open containers. The specular reflection contributions to the radiation force of two slanted plane waves incident on a rigid cylinder is approximated and compared with a full partial wave series (PWS) solution for an infinitely long cylinder in an inviscid fluid. The availability of the PWS solution gives support to approximations introduced in the geometric analysis, provided ka (the wave number-cylinder-radius product) is sufficiently large. The normalized force projection is plotted as a function of the wave slant angle relative to the symmetry axis. Deviations between the specular and PWS analysis for ka of 7.5 are diminished for ka of 15 and 25. A region of enhanced force associated with constructive interference narrows with increasing ka.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-02T02:00:09Z
       
  • Model resolution matrix based deconvolution improves over non-quadratic
           penalization in frequency-domain photoacoustic tomography

    • Free pre-print version: Loading...

      Authors: Hemanth S. Nakshatri, Jaya Prakash
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1345-1356, September 2022.
      Frequency domain photoacoustic tomography is becoming more attractive due to low-cost and compact light-sources being used; however, frequency-domain implementation suffers from lower signal to noise compared to time-domain implementation. In this work, we have developed a non-quadratic based penalization framework for frequency-domain photoacoustic imaging, and further proposed a two-step model-resolution matrix based deconvolution approach to improve the reconstruction image quality. The model-resolution matrix was developed in the context of different penalty functions like l2-norm, l1-norm, Cauchy, and Geman-McClure. These model-resolution matrices were then used to perform the deconvolution operation using split augmented Lagrangian shrinkage thresholding algorithm in both full-view and limited-view configurations. The results indicated that the two-step approach outperformed the different penalty function (prior constraint) based reconstruction, with an improvement of about 20% in terms of peak signal to noise ratio and 30% in terms of structural similarity index measure. The improved image quality provided using these algorithms will have a direct impact on realizing practical frequency-domain implementation in both limited-view and full-view configurations.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-02T02:00:08Z
       
  • Shallow-water waveguide acoustic analysis in a fluctuating environment

    • Free pre-print version: Loading...

      Authors: Samuel Pinson, Victor Quilfen, Florent Le Courtois, Gaultier Real, Dominique Fattaccioli
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1252-1262, September 2022.
      The Acoustic Laboratory for Marine Applications (ALMA) is a deployable and autonomous acoustic system, designed by DGA Naval Systems, to address problems in underwater acoustics, such as sound propagation in fluctuating environments. In this article, data from the ALMA-2016 at-sea campaign are used to analyze the ocean fluctuation's influence on sound propagation in a shallow-water waveguide. The experiment took place on the continental shelf of the island of Corsica in November 2016. A source and a receiver array were 9.3 km apart in a nearly constant water depth of 100 m. The source emitted a variety of signals from which the chirp (1–13 kHz) is used to extract the waveguide eigenrays. To do so, a time-domain beamforming is performed on the match-filtered received signals with an automatic detection of local maxima in the time of arrival/direction of arrival (TOA/DOA) domain. A 2 min acquisition period of more than 13 h duration shows significant fluctuations in eigenray TOAs/DOAs. Qualitative comparisons with synthetic signals obtained from simulations in two and three dimensions permit reproduction of the observed eigenray fluctuations without including range dependence of the sound-speed profile.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-01T02:22:46Z
       
  • Super-resolution within a one-dimensional phononic crystal of resonators
           using time reversal in an equivalent circuit model

    • Free pre-print version: Loading...

      Authors: Adam D. Kingsley, Brian E. Anderson, T. J. Ulrich
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1263-1271, September 2022.
      An equivalent circuit model has been developed to model a one-dimensional waveguide with many side-branch Helmholtz resonators. This waveguide constitutes a phononic crystal that has been shown to have decreased phase speed below the resonance frequency of an individual resonator. This decreased phase speed can be exploited to achieve super-resolution using broadband time reversal focusing techniques. It is shown that the equivalent circuit model is capable of quantifying this change in phase speed of the crystal and also the small-scale wave-resonator interactions within the crystal. The equivalent circuit model enables the parameterization of the physical variables and the optimization of the focusing bandwidth by balancing the combination of increasing resolution and decreasing amplitude near the resonance frequency. It is shown that the quality factor—in this case, the quality factor determined by the geometric shape of each resonator—controls the range of frequencies that are strongly affected by the Helmholtz resonators.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-01T02:22:44Z
       
  • Brain-inspired sensorimotor echolocation system for confident landmark
           recognition

    • Free pre-print version: Loading...

      Authors: Roman Kuc
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1272-1282, September 2022.
      A landmark is a familiar target in terms of the echoes that it can produce and is important for echolocation-based navigation by bats, robots, and blind humans. A brain-inspired system (BIS) achieves confident recognition, defined as classification to an arbitrarily small error probability (PE), by employing a voting process with an echo sequence. The BIS contains sensory neurons implemented with binary single-layer perceptrons trained to classify echo spectrograms with PE and generate excitatory and inhibitory votes in face neurons until a landmark-specific face neuron achieves recognition by reaching a confidence vote level (CVL). A discrete random step process models the vote count to show the recognition probability can achieve any desired accuracy by decreasing PE or increasing CVL. A hierarchical approach first classifies surface reflector and volume scatterer target categories and then uses that result to classify two subcategories that form four landmarks. The BIS models blind human echolocation to recognize four human-made and foliage landmarks by acquiring suitably sized and dense audible echo sequences. The sensorimotor BIS employs landmark-specific CVL values and a 2.7° view increment to acquire echo sequences that achieve zero-error recognition of each landmark independent of the initial view.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-01T02:22:43Z
       
  • Maximum likelihood separation of anthropogenic and wind-generated
           underwater noise

    • Free pre-print version: Loading...

      Authors: Robin Larsson Nordström, Emilia Lalander, Isaac Skog, Mathias Andersson
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1292-1299, September 2022.
      A method is presented for simultaneous estimation of the probability distributions of both anthropogenic and wind-generated underwater noise power spectral density using only acoustic data recorded with a single hydrophone. Probability density models for both noise sources are suggested, and the model parameters are estimated using the method of maximum likelihood. A generic mixture model is utilized to model a time invariant anthropogenic noise distribution. Wind-generated noise is assumed normally distributed with a wind speed-dependent mean. The mean is then modeled as an affine linear function of the wind-generated noise level at a reference frequency, selected in a frequency range where the anthropogenic noise is less dominant. The method was used to successfully estimate the wind-generated noise spectra from ambient noise recordings collected at two locations in the southern Baltic Sea. At the North location, 3 km from the nearest shipping lane, the ship noise surpasses the wind-generated noise almost 100% of the time in the frequency band 63–400 Hz during summer for wind speed 7 m/s. At the South location, 14 km to the nearest shipping lane, the ship noise dominance is lower but still 40%–90% in the same frequencies and wind speed.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-01T02:22:41Z
       
  • REVIEWS OF ACOUSTICAL PATENTS

    • Free pre-print version: Loading...

      Authors: Sean A. Fulop
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1247-1251, September 2022.
      The purpose of these acoustical patent reviews is to provide enough information for a Journal reader to decide whether to seek more information from the patent itself. Any opinions expressed here are those of the reviewers as individuals and are not legal opinions. Patents are available via the internet at the USPTO website.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-01T02:22:40Z
       
  • Digital sampling of acoustic impulse noise: Implications for exposure
           measurement and damage risk criteria

    • Free pre-print version: Loading...

      Authors: Christoper J. Smalt, Douglas S. Brungart
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1283-1291, September 2022.
      Current standards for the measurement of impulse noise (e.g., MIL-STD-1474E) recommend using a sampling rate of at least 200 kHz in order to accurately estimate the risk of hearing damage. The given motivation for this high sampling rate is to ensure a temporal resolution in the impulse waveform fine enough to accurately capture the peak pressure. However, the Nyquist-Shannon sampling theorem specifies that a sampled signal can accurately reconstruct both the amplitude and phase information of a signal given the sampling rate is at least twice the highest frequency present in the original signal. Thus, it is possible to reconstruct a band limited signal with the same temporal resolution as one captured at a higher sampling rate if the contributions of energy above the Nyquist rate can be ignored. In this study, resampling techniques are applied to a signal sampled at 48 kHz to extract A-weighted sound pressure energy estimates within 0.1 dB of those obtained at a higher sampling rate. Our results suggest sampling rates for impulsive noise should be based on the range of frequencies expected to make a contribution to injury risk rather than on concerns about temporal resolution.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-01T02:22:40Z
       
  • The application of acoustics to heat engines and refrigerators

    • Free pre-print version: Loading...

      Authors: Steven Garrett
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page R5-R6, September 2022.
      The Reflections series takes a look back on historical articles from The Journal of the Acoustical Society of America that have had a significant impact on the science and practice of acoustics.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-01T02:22:27Z
       
  • Strategic perceptual weighting of acoustic cues for word stress in
           listeners with cochlear implants, acoustic hearing, or simulated bimodal
           hearing

    • Free pre-print version: Loading...

      Authors: Justin T. Fleming, Matthew B. Winn
      Abstract: The Journal of the Acoustical Society of America, Volume 152, Issue 3, Page 1300-1316, September 2022.
      Perception of word stress is an important aspect of recognizing speech, guiding the listener toward candidate words based on the perceived stress pattern. Cochlear implant (CI) signal processing is likely to disrupt some of the available cues for word stress, particularly vowel quality and pitch contour changes. In this study, we used a cue weighting paradigm to investigate differences in stress cue weighting patterns between participants listening with CIs and those with normal hearing (NH). We found that participants with CIs gave less weight to frequency-based pitch and vowel quality cues than NH listeners but compensated by upweighting vowel duration and intensity cues. Nonetheless, CI listeners' stress judgments were also significantly influenced by vowel quality and pitch, and they modulated their usage of these cues depending on the specific word pair in a manner similar to NH participants. In a series of separate online experiments with NH listeners, we simulated aspects of bimodal hearing by combining low-pass filtered speech with a vocoded signal. In these conditions, participants upweighted pitch and vowel quality cues relative to a fully vocoded control condition, suggesting that bimodal listening holds promise for restoring the stress cue weighting patterns exhibited by listeners with NH.
      Citation: The Journal of the Acoustical Society of America
      PubDate: 2022-09-01T02:22:23Z
       
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
 


Your IP address: 3.238.49.228
 
Home (Search)
API
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-