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This study used the Musical Ear Test [Wallentin, Nielsen, Friis-Olivarius, Vuust, and Vuust (2010). Learn. Indiv. Diff. 20, 188-196] to compare musical aptitude of native Japanese and Chinese speakers. Although the two groups had similar overall accuracy, they showed significant differences in subtest performance. Specifically, the Chinese speakers outperformed the Japanese counterparts on the melody subtest, but the reverse was observed on the rhythm subtest. Within-group comparisons revealed that Chinese speakers performed better on the melody subtest than the rhythm subtest, while Japanese speakers showed an opposite trend. These results indicate that native language pitch and durational patterns of the listener can have a profound effect on the perception of music melody and rhythm, respectively, reflecting language-to-music transfer of learning.The objective occlusion effect induced by bone-conducted stimulation refers to the low frequency acoustic pressure increase that results from occluding the ear canal opening. This phenomenon is commonly interpreted as follows the bone-conducted sound "leaks" through the earcanal opening and is "trapped" by the occlusion device. This instinctive interpretation misrepresents the fundamental mechanism of the occlusion effect related to the earcanal impedance increase and already highlighted by existing electro-acoustic models. However, these models simplify the earcanal wall vibration (i.e., the origin of the phenomenon) to a volume velocity source which, in the authors' opinion, (i) hinders an exhaustive comprehension of the vibro-acoustic behavior of the system, (ii) hides the influence of the earcanal wall vibration distribution, and (iii) could blur the interpretation of the occlusion effect. This paper analyzes, illustrates, and interprets the vibro-acoustic behavior of the open and occluded earcanal using an improved finite element model of an outer ear in conjunction with an associated electro-acoustic model developed in this work. The two models are very complementary to dissect physical phenomena and to highlight the influence of the earcanal wall vibration distribution, characterized here by its curvilinear centroid position, on the occlusion effect.Boundary integral analysis of scattering from rigid bodies is well known. Analysis often proceeds along the following lines representation of the geometry using a collection of triangles, representation of physics using low order ansatz functions defined on each triangle, and then solving the resulting discrete system. This prescription for the common solution stands out in terms of the low-order approximation of both geometry and representation of physics; specifically, both are C0. Taking inspiration from computer graphics literature, a framework wherein continuity of representation (both geometry and physics) can be as high as C2 is developed. In this paper, the steps necessary to develop such a iso-geometric (i.e., using the same basis functions for representing both geometry and physics) boundary integral solver are elucidated. In doing so, an efficient method based on a wideband fast multipole method to evaluate the required inner products and matrix vector products is proposed and demonstrated. Numerous examples are presented to highlight the benefits of the proposed approach.Individual acoustic parameters of reverberation have the potential to affect both the intelligibility of speech and the degree of perceived reverberation. The current experiments used monaural acoustic simulations to investigate the effect of reverberation time (RT) and direct-to-reverberant ratio (DRR) on word and sentence intelligibility at different levels of analysis (phonemes, words, and sentences). Perceived reverberation and recall of sentences were also assessed. Intelligibility and perceived reverberation decreased with increasing RT and decreasing DRR (particularly between 0 and -10 dB). Results indicate consistent effects of both RT and DRR on the intelligibility and perceived reverberation of words and sentences.This paper investigates the evolution of spectral properties observed in Cuvier's beaked whale (Ziphius cavirostris) click trains recorded by fixed hydrophones in the Gulf of Mexico. In the context of deep water and high-frequency sounds and observed inter-click intervals, the authors assumed that the main effect responsible for the modification of the spectral content between adjacent clicks in the same click train is the source beam pattern. The spectral structure is studied by using the Wigner-Ville time-frequency distribution and is compared with the conventional Fourier spectrogram. The results show that the observed Cuvier's beaked whale clicks are a superposition of upsweep and downsweep chirps, unlike the currently accepted upsweep only structure of beaked whale clicks in bioacoustics literature. The spectral structure variations simulated by using a flat circular piston model as a beam pattern transmission model are consistent with the evolution of spectral click properties observed in experimental data. A better understanding of the properties of observed echolocation clicks of Cuvier's beaked whales will provide useful information for click annotations and, therefore, will contribute to improving accuracy of detecting, classifying, tracking, and estimating the density of Cuvier's beaked whales.Ultrasound computed tomography (USCT) is a noninvasive imaging modality that has shown its clinical relevance for breast cancer diagnostics. As opposed to traveltime inversions, waveform-based inversions can exploit the full content of ultrasound data, thereby providing increased resolution. However, this is only feasible when modeling the full physics of wave propagation, accounting for 3D effects such as refraction and diffraction, and this comes at a significant computational cost. To mitigate this cost, a crosstalk-free source encoding method for explicit time-domain solvers is proposed. The gradient computation is performed with only two numerical "super" wave simulations, independent of the number of sources and receivers. Absence of crosstalk is achieved by considering orthogonal frequencies attributed to each source. By considering "double-difference" measurements, no a priori knowledge of the source time function is required. With this method, full-physics based 3D waveform inversions can be performed within minutes using reasonable computational resources, fitting clinical requirements.Signal-to-noise ratio (SNR) estimation is necessary for many speech processing applications often challenged by nonstationary noise. The authors have previously demonstrated that the variance of spectral entropy (VSE) is a reliable estimate of SNR in nonstationary noise. Based on pre-estimated VSE-SNR relationship functions, the SNR of unseen acoustic environments can be estimated from the measured VSE. This study predicts that introducing a compressive function based on cochlear processing will increase the stability of the pre-estimated VSE-SNR relationship functions. This study demonstrates that calculating the VSE based on a nonlinear filter-bank, simulating cochlear compression, reduces the VSE-based SNR estimation errors. VSE-SNR relationship functions were estimated using speech tokens presented in babble noise comprised of different numbers of speakers. Results showed that the coefficient of determination (R2) of the estimated VSE-SNR relationship functions have absolute percentage improvements of over 26% when using a filter-bank with a compressive function, compared to when using a linear filter-bank without compression. In 2-talker babble noise, the estimation accuracy is more than 3 dB better than other published methods.Advanced acoustic levitation devices featuring flexible, lightweight, wide bandwidth, and film-like transducers based on ferroelectrets are designed and fabricated for sophisticated manipulation of particles in a simple way. Owing to the unique properties of ferroelectret films, such as high piezoelectric activity, very small acoustic impedance, a relatively large damping ratio, flexibility, a large area, and small density, the levitator reported features a wider bandwidth compared to ceramic-based levitators. The transportation of levitated particles is achieved by deformation of the film transducer, which represents a different and promising concept for this task.Clear speech is a style that speakers adopt when talking with listeners whom these speakers anticipate may have a problem understanding speech. This study examines whether native English speakers use clear speech in conversations with non-native English speakers when native speakers are not explicitly asked to use clear speech (i.e., clear speech elicited with naturalistic methods). The results of the study suggest that native English speakers use clear speech in conversations with non-native English speakers even when native speakers are not explicitly asked to. Native English speakers' speech is more intelligible in the early portions of the conversations than in the late portions of each conversation. Further, the speakers "reset" to clearer speech at the start of each Diapix picture. Additionally, acoustic properties of the speech are examined to complement the intelligibility results. These findings suggest the instigation of clear speech may be listener-driven but the maintenance of clear speech is likely more speaker-driven.In ocean acoustics, many types of optimizations have been employed to locate acoustic sources and estimate the properties of the seabed. How these tasks can take advantage of recent advances in deep learning remains as open questions, especially due to the lack of labeled field data. [https://www.selleckchem.com/products/Staurosporine.html Staurosporine chemical structure] In this work, a Convolutional Neural Network (CNN) is used to find seabed type and source range simultaneously from 1 s pressure time series from impulsive sounds. Simulated data are used to train the CNN before application to signals from a single hydrophone signal during the 2017 Seabed Characterization Experiment. The training data includes four seabeds representing deep mud, mud over sand, sandy silt, and sand, and a wide range of source parameters. When applied to measured data, the trained CNN predicts expected seabed types and obtains ranges within 0.5 km when the source-receiver range is greater than 5 km, showing the potential for such algorithms to address these problems.Distortion-product otoacoustic emissions (DPOAEs) emerge from the cochlea when elicited with two tones of frequencies f1 and f2. DPOAEs mainly consist of two components, a nonlinear-distortion and a coherent-reflection component. Input-output (I/O) functions of DPOAE pressure at the cubic difference frequency, fDP=2f1-f2, enable the computation of estimated distortion-product thresholds (EDPTs), offering a noninvasive approach to estimate auditory thresholds. However, wave interference between the DPOAE components and suboptimal stimulus-level pairs reduces the accuracy of EDPTs. Here, the amplitude P of the nonlinear-distortion component is extracted from short-pulse DPOAE time signals. DPOAE level maps representing the growth behavior of P in L1,L2 space are recorded for 21 stimulus-level pairs and 14 frequencies with f2=1 to 14 kHz (f2/f1=1.2) from 20 ears. Reproducing DPOAE growth behavior using a least-squares fit approach enables the derivation of ridge-based I/O functions from model level maps. Objective evaluation criteria assess the fit results and provide EDPTs, which correlate significantly with auditory thresholds (p less then 0.