JASA express letters最新文献

This paper presents Bayesian matched-field geoacoustic inversion results based on measurements from a single hydrophone. To efficiently compute the posterior distribution, we employ an adaptive Metropolis-Hastings sampling strategy, which dynamically adjusts the proposal distribution. Our method is applied to experimental data from the Shallow Water 2006 experiment, considering two broadband acoustic sources. The inversion targets four key parameters: source range, source depth, water depth, and sediment compressional sound speed. We present results indicating that Bayesian single-hydrophone inversions can provide accurate parameter estimates, underscoring their utility in resource-limited or rapid-deployment scenarios.

This work lies at the intersection between Willis media, tunable acoustic metamaterials, and multi-material three-dimensional printing. A four-microphone, two-termination impedance tube was used to measure the acoustic response of a subwavelength scatterer composed of two resonant plates. The resonance frequency of one plate was controlled via resistive heating, which introduced a geometric asymmetry, observed dynamically through reflection coefficients that differed depending on the incident wave direction. For the acoustically small scatterer, coupled polarizabilities meaningfully captured the tuned asymmetry and characterized the observed Willis coupling. Model-data comparison shows good agreement between the measured and modeled results.

Wedge-like shallow water modeling is often used for sound field propagation in near-coastal zones of oceans. The canonical model, which has an analytical solution and is used in many applications, assumes a constant sound speed in the water layer. Recently it was shown by Jiang, Zhang and Katnelson [JASA Express Lett. 3, 016001 (2023)], however, that the presence of a thermocline significantly changes the structure of the sound field when propagating downslope due to the emerging specific mode coupling. In this paper, the problem of the sound field in such a wedge is considered for upslope propagation. The sound field is constructed both using an expansion over adiabatic modes and a parabolic equation. It is demonstrated that the mode coupling arising due to local violation of adiabaticity leads to noticeable variability of the spatial distribution of the field, i.e., the field decomposition by modes. The results are illustrated by calculations using real parameters in shallow water.

This study examines the extent to which Mandarin-speaking listeners rely on low-level acoustic information when identifying new talkers speaking Mandarin-accented English (MAE), native Mandarin (NM), and native English (NE). Identification accuracy was highest for NM, intermediate for MAE, and lowest for NE, replicating language/accent familiarity effects. Representational similarity analysis comparing listeners' behavioral responses with talkers' low-level acoustic features (e.g., F0, jitter) revealed less reliance on these acoustic cues in more familiar contexts (e.g., NM vs NE). In MAE context, acoustic reliance decreased with training despite improved accuracy, suggesting a shift away from talker identification strategies based on low-level acoustic processing.

This study aimed to characterize maturation of the binaural intelligibility level difference (BILD) for school-age children in the context of speech-in-speech recognition. Children (5-17 years) and adults completed an adaptive, open-set sentence recognition task in a two-talker masker in two binaural conditions: (1) target and masker speech in-phase across the two ears, and (2) target speech presented 180° out-of-phase across the two ears and masker speech presented in-phase. Estimates of the BILD, computed as the difference score between the two binaural conditions, were mature by ten years of age, consistent with previous data on the BILD for speech-in-noise recognition.

A general theory for obtaining spherical wave function expansion coefficients for a sound beam transmitted by a planar velocity source is presented. By neglecting evanescent wave components and thus making the proposed method only approximate in the near field, it is shown that these coefficients can be obtained for any expansion point using just the normal velocity condition in the source plane. Additionally, simplifications are presented for axisymmetric sources. Results are compared with direct numerical evaluation of the Rayleigh integral for source conditions corresponding to a circular and rectangular piston. The present theory can be used in calculations of acoustic scattering and radiation force for spherical objects, or in spherical acoustical holography applications.

To accurately characterize the non-radial motion of the source relative to the receiver, a three-dimensional (3D) model is essential. The extended Kalman filter (EKF) state matrix is employed to characterize the source's 3D motion. The measurement input for the EKF is the time delay between the direct and surface-reflected arrivals. The differences in the partial derivatives of the distance component have been identified and discussed. Through iterative filtering, a reliable estimate of the source's position in 3D space is obtained. Both simulations and experiments validate the effectiveness of the method, with experimental depth estimation errors within 1.5%.

Spatially separating target and masker talkers improves speech perception in noise, an effect known as spatial release from masking (SRM). Independently, the perceived location of a sound can erroneously shift towards an associated but spatially displaced visual stimulus (the "ventriloquist effect"). This study investigated whether SRM can be induced by spatially separating visual stimuli associated with a target and masker without separating the sound sources themselves. Results showed that SRM was not induced by spatially separated visual stimuli, but collocated visual stimuli reduced the benefit of auditory SRM. There was no influence of individual differences in auditory localization ability on effects related to the visual stimuli.

This study examined relationships between cochlear implant-aided speech recognition, sound quality ratings, and quality of life outcomes in 41 adult cochlear implant users. Participants completed word and sentence recognition tasks, the Speech, Spatial and Qualities (SSQ) questionnaire, and the Cochlear Implant Quality of Life (CIQOL) questionnaire. Sound quality ratings on SSQ showed a weak correlation with sentence recognition in noise but strong positive correlations with CIQOL scores. Sound quality independently predicted quality of life, explaining 32% of global score variance, while speech recognition measures showed no effects. These findings highlight sound quality as a distinct and meaningful outcome metric.

This study presents a non-destructive method for estimating surface acoustic wave attenuation, which is highly sensitive to microstructural features, especially at high frequencies. The method uses a single wideband dispersive interdigital transducer (IDT) that remotely emits acoustic waves at the sample's edge. Chirp compression of the temporal displacement response is achieved by correlating the excitation signal with the spatial configuration of the IDT's electrodes. This technique generates high-amplitude pulses with a sufficient signal-to-noise ratio, critical for enabling accurate attenuation estimation over a frequency range (15-70 MHz). Results from nickel and aluminum demonstrate the method's effectiveness for rapid material characterization.