JASA express letters最新文献

This paper describes Omura's whale vocalizations recorded off northern Australia. Most common was a two-unit "doublet" (17-50 Hz, peak 25.5 Hz, duration ∼15 s). This was rhythmically repeated for extended periods of time, in typical baleen-whale song structure, suggesting it is a male breeding display. A one-unit "singlet" occurred in the lower-latitude locations off the northwest (13-72 Hz, peak 26.6 Hz, 8 s). In the Great Barrier Reef, similar doublets were detected, identifying a possible population of the species in the Southwest Pacific. Such geographic variation of song may benefit passive acoustic monitoring of this species for conservation management.

In wind-wave driven ambient sound environments, the cross-correlation of acoustic data recorded on vertically separated hydrophones can provide estimates of the average sound speed between hydrophones. Deployment of a 52-element vertical line array of hydrophones located on a 425 m deep ridge in the Nordic waters near Jan Mayen Island enabled estimates of the water column sound speed profile. Sound speed profiles were estimated for each 24-min recording, which were collected every four hours over the course of the year-long experiment, supplying a wide range of environmental conditions. Over the full experiment, estimated sound speeds had a root-median-square error of 0.79 m/s when compared to direct measurements.

The oceans are filled with acoustic waves, which are trapped in a low-velocity layer at about 1 km water depth. The sound speed depends on the temperature. From hydroacoustic arrays, travel times can be obtained through cross-correlating transient signals. Hydroacoustic station H10 (Ascension Island) appeared capable of measuring deep ocean temperature change. A decrease in modeled and observed travel times of -0.002 s/yr was derived between two arrays, corresponding to a warming of 0.007 °C/yr, at about 900 m water depth over two decades. As such, acoustic waves provide an independent and passively acquired measure of the temperature change in the deep ocean.

A recent study in individuals with hyperfunctional voice disorders (HVDs) reported poorer fo discrimination compared to matched controls. In that study, fo discrimination was measured using each individual's own voice as the stimulus, which may have introduced confounds given the differences in vocal quality between the groups. Here, this paper addressed this possibility by using an fo discrimination task where participants with and without HVDs judged the same external voice. In line with the previous study, the HVD group exhibited poorer fo discrimination than controls, providing convergent evidence for a pitch-related auditory deficit in this population.

Degraded speech intelligibility in multitalker situations can be improved by spatial unmasking, using sound spatialization techniques such as binaural synthesis. However, intelligibility also depends on the ability to focus efficiently on the target. Three experimental sessions explored the benefit of an additional vibrotactile cue, spatialized around the waist, on intelligibility in different spatialized multitalker situations. Results indicate improvements in intelligibility scores and reduced listening effort specifically for an off-center target among masker talkers. Multimodality allows us to better understand the mechanisms of auditory attention and to open up new perspectives for improving speech intelligibility in multitalker situations.

The complexity of deep-sea acoustic ray bending is positively correlated with propagation distance, typically turning beyond 10 km. Existing ranging correction methods fail under turning conditions, limiting ranging accuracy. This letter proposes an effective sound velocity estimation method for turning ray, based on reliable acoustic path boundary to classify turning direct sound and establish a ray-tracing model for ranging correction. This method extends high-accuracy ranging from a 10 km scale to the first convergence zone. Experimental results demonstrate that the method achieves a positioning precision of 6.18 m at a horizontal distance of 34 km, validating its effectiveness.

This study presents a probabilistic one-step two-dimensional (2D) inversion method of spherical-wave reflection coefficient data to estimate the range-dependent structure and geoacoustic parameters along a track. The approach of inverting such datasets independently as one-dimensional (1D) layered models and merging them to a 2D section is feasible but computationally expensive. This study demonstrates a more parsimonious 2D parametrization for active source data recorded on a towed hydrophone array. The comparison of data variance reduction for 1D- and 2D-based results clearly favors the 2D parametrization described here.

Trans-dimensional (trans-D) Bayesian inversion is a powerful approach to estimate seabed geoacoustic models from ocean-acoustic data, combining quantitative model selection and uncertainty estimation. Trans-D inversion samples probabilistically over the number of seabed layers and the geoacoustic parameters for each layer, with layers added and removed in sampling, changing the dimension of the model. However, the probability of accepting dimension changes can approach zero for problems involving highly informative data or large numbers of parameters per layer. This Letter examines the use of parallel tempering, which employs a sequence of interacting Markov chains with successively relaxed likelihoods, to address these challenging cases.

In this study, the question of generalization for dimension-based statistical learning in speech perception is revisited. Learning for F0 and voice-onset-time as cues to stop voicing has been suggested to be fairly specific to a particular contrast, which was previously shown not to generalize between two places of articulation. The present study seeks to replicate generalization for the same place of articulation, using more varied stimuli and a different design. Then, it is tested if increased evidence for a distributional pattern, i.e., two places of articulation showing that pattern, leads to generalization to a third place of articulation. Same place of articulation learning is replicated, and no generalization across place of articulation is found, reaffirming that learning appears to be quite specific.

The size of an individual's tongue relative to the oral cavity is associated with articulation speed [Feng, Lu, Zheng, Chi, and Honda, in Proceedings of the 10th Biennial Asia Pacific Conference on Speech, Language, and Hearing (2017), pp. 17-19)] and may affect speech clarity. This study introduces an ultrasound-based method for measuring relative tongue size, termed ultrasound-based relative tongue size (uRTS), as a cost-effective alternative to the magnetic resonance imaging (MRI) based method. Using deep learning to extract the tongue contour, uRTS was calculated from tongue and oropharyngeal cavity sizes in the midsagittal plane. Results from ten speakers showed a strong correlation between uRTS and MRI-based measurements (r = 0.87) and a negative correlation with tongue movement speed (r = -0.73), indicating uRTS is a useful index for assessing tongue size.