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areas had similar characteristics and evaluated the support centre similarly to those living in more urban areas.Typhoon-induced P-wave microseisms can be observed using seismological arrays and analyzed for the seismic monitoring of ocean storms. This paper presents a frequency-domain beamforming (FB) method that integrates a three-dimensional (3-D) Earth model to better capture the heterogeneities in the subsurface structure, and therefore yield more accurate ray-tracing and travel-time predictions. This method is applied to the Super Typhoon Lupit (2009) using seismological array observations from the Northeast China Extended Seismic Array (NECESSArray) and high-sensitivity seismograph network in Japan (Hi-net). The results show that the localized P-wave microseism source regions based on the 3-D model are in better agreement with the theoretical source regions and typhoon centers than those based on a conventional one-dimensional (1-D) model. The significance of using a 3-D model instead of a 1-D model in the FB method is further investigated by comparing the consistency of the localization results for the two different arrays, with the localized source regions being more mutually concordant when using the 3-D model. The results demonstrate that integrating the 3-D model into the FB method improves the accuracy of locating the typhoon-induced P-wave microseism source regions.Auditory evoked potentials (AEPs) include the auditory brainstem response (ABR), middle latency response (MLR), and cortical auditory evoked potentials (CAEPs), each one covering a specific latency range and frequency band. For this reason, ABR, MLR, and CAEP are usually recorded separately using different protocols. This article proposes a procedure providing a latency-dependent filtering and down-sampling of the AEP responses. This way, each AEP component is appropriately filtered, according to its latency, and the complete auditory pathway response is conveniently represented (with the minimum number of samples, i.e., without unnecessary redundancies). The compact representation of the complete response facilitates a comprehensive analysis of the evoked potentials (keeping the natural continuity related to the neural activity transmission along the auditory pathway), which provides a new perspective in the design and analysis of AEP experiments. Additionally, the proposed compact representation reduces the storage or transmission requirements when large databases are manipulated for clinical or research purposes. The analysis of the AEP responses shows that a compact representation with 40 samples/decade (around 120 samples) is enough for accurately representing the response of the complete auditory pathway and provides appropriate latency-dependent filtering. MatLab/Octave code implementing the proposed procedure is included in the supplementary materials.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.A recently proposed deconvolution method applied to conventional beamforming (CBF) shows a much higher array gain (AG) than CBF in theory, thereby providing the possibility for detecting a weak signal with a much lower signal-to-noise ratio (SNR). However, simulated data processing shows an effective AG that decreases with decreasing SNR. The reason for the performance loss is analyzed. A method based on deconvolution of the signal subspace of the CBF outputs is shown to recover most of the AG loss. It is used to trace a weak signal in bearing and time.Access to the original Lascaux cave, a UNESCO World Heritage site famous for its 18 000 year old paintings, has been restricted since 1963. In 2016, an accurate facsimile, Lascaux IV, was designed and built. In the original cave, Lascaux I, classical contemporary room acoustics measurement systems could not be used. However, it has been possible to perform simplified measurements in a few minutes. Similar measurements were made in Lascaux IV once completed. The data provide a unique insight of the acoustic behavior of the Lascaux cave it shows that the two caves, the original and the copy, have similar acoustical characteristics. In both cases, in the famed Hall of Bulls, the impulse response is smooth, reverberation time is relatively long, and speech intelligibility is fair; this environment is suitable for the ceremonies that presumably took place there. Because of the precision of the copy, Lascaux IV could be used as a 1/1 scale-model of Lascaux I. Therefore, sophisticated acoustical tests could be undertaken in Lascaux IV to help specialists in their archeological investigations. For example, resonances could be precisely documented to explore the potential relationship between parietal painting positions and echoes or sound effects that may have been used in ritual ceremonies.Speech production variability introduces significant challenges for existing speech technologies such as speaker identification (SID), speaker diarization, speech recognition, and language identification (ID). There has been limited research analyzing changes in acoustic characteristics for speech produced by untrained singing versus speaking. To better understand changes in speech production of the untrained singing voice, this study presents the first cross-language comparison between normal speaking and untrained karaoke singing of the same text content. Previous studies comparing professional singing versus speaking have shown deviations in both prosodic and spectral features. Some investigations also considered assigning the intrinsic activity of the singing. MDL-800 cell line Motivated by these studies, a series of experiments to investigate both prosodic and spectral variations of untrained karaoke singers for three languages, American English, Hindi, and Farsi, are considered. A comprehensive comparison on common prosodic features, including phoneme duration, mean fundamental frequency (F0), and formant center frequencies of vowels was performed. Collective changes in the corresponding overall acoustic spaces based on the Kullback-Leibler distance using Gaussian probability distribution models trained on spectral features were analyzed. Finally, these models were used in a Gausian mixture model with universal background model SID evaluation to quantify speaker changes between speaking and singing when the audio text content is the same. The experiments showed that many acoustic characteristics of untrained singing are considerably different from speaking when the text content is the same. It is suggested that these results would help advance automatic speech production normalization/compensation to improve performance of speech processing applications (e.g., speaker ID, speech recognition, and language ID).Under sound change of stops in Kyungsang Korean, this study examined how the voice onset time (VOT) and F0 cues to the aspirated-lenis stop contrast were used in the productions of children, teenagers, young adults, and elderly speakers. Results showed that the three younger groups were more innovative in using VOT than the elderly speakers, but the use of F0 was not as innovative as the use of VOT. This study suggests that although there is some difference between Seoul and Kyungsang Korean, the sound change in Kyungsang Korean stops is incrementally similar to the change in Seoul Korean stops.While acoustic vortex beams have many potential applications, the full implication of the phase information available in scattering experiments has not been developed. The present paper concerns observables in measured near-backward scattering from a sphere in water raster scanned through a first-order acoustic vortex beam. Symmetrically placed transducer elements were operated in a transmit-receive mode. Helicity-dependent projections of the spatial evolution of the scattering were used to display magnitude and phase information. The resulting phase swirl patterns were projection dependent and especially sensitive to the transverse position of the sphere. The magnitude also depended on the sphere's position relative to the beam's axial null.The magnitudes by which aberration and incoherent noise sources, such as diffuse reverberation and thermal noise, contribute to degradations in image quality in medical ultrasound are not well understood. Theory predicting degradations in spatial coherence and contrast in response to combinations of incoherent noise and aberration levels is presented, and the theoretical values are compared to those from simulation across a range of magnitudes. A method to separate the contributions of incoherent noise and aberration in the spatial coherence domain is also presented and applied to predictions for losses in contrast. Results indicate excellent agreement between theory and simulations for beamformer gain and expected contrast loss due to incoherent noise and aberration. Error between coherence-predicted aberration contrast loss and measured contrast loss differs by less than 1.5 dB on average, for a -20 dB native contrast target and aberrators with a range of root-mean-square time delay errors. Results also indicate in the same native contrast target the contribution of aberration to contrast loss varies with channel signal-to-noise ratio (SNR), peaking around 0 dB SNR. The proposed framework shows promise to improve the standard by which clutter reduction strategies are evaluated.There is high spatial overlap between grey seals and shipping traffic, and the functional hearing range of grey seals indicates sensitivity to underwater noise emitted by ships. However, there is still very little data regarding the exposure of grey seals to shipping noise, constraining effective policy decisions. Particularly, there are few predictions that consider the at-sea movement of seals. Consequently, this study aimed to predict the exposure of adult grey seals and pups to shipping noise along a three-dimensional movement track, and assess the influence of shipping characteristics on sound exposure levels. Using ship location data, a ship source model, and the acoustic propagation model, RAMSurf, this study estimated weighted 24-h sound exposure levels (10-1000 Hz) (SELw). Median predicted 24-h SELw was 128 and 142 dB re 1 μPa2s for the pups and adults, respectively. The predicted exposure of seals to shipping noise did not exceed best evidence thresholds for temporary threshold shift. Exposure was mediated by the number of ships, ship source level, the distance between seals and ships, and the at-sea behaviour of the seals. The results can inform regulatory planning related to anthropogenic pressures on seal populations.Spectral estimation is a necessary methodology to analyze the frequency content of noisy data sets especially in acoustic applications. Many spectral techniques have evolved starting with the classical Fourier transform methods based on the well-known Wiener-Khintchine relationship relating the covariance-to-spectral density as a transform pair culminating with more elegant model-based parametric techniques that apply prior knowledge of the data to produce a high-resolution spectral estimate. Multichannel spectral representations are a class of both nonparametric, as well as parametric, estimators that provide improved spectral estimates. In any case, classical nonparametric multichannel techniques can provide reasonable estimates when coupled with peak-peaking methods as long as the signal levels are reasonably high. Parametric multichannel methods can perform quite well in low signal level environments even when applying simple peak-picking techniques. In this paper, the performance of both nonparametric (periodogram) and parametric (state-space) multichannel spectral estimation methods are investigated when applied to both synthesized noisy structural vibration data as well as data obtained from a sounding rocket flight.