bluuebunny/crossref_metadata_2025 huggingface dataset:
An individual differences approach to acoustic context effects in speech categorization
Authors: Stilp Christian
Published: April 2019

Objects and events in the sensory environment are not perceived in isolation but in the context of surrounding stimuli. This fact has been widely appreciated in the study of speech perception, as demonstrations of these context effects date back more than a half-century. For example, the spectral composition of surrounding sounds can bias categorization of later speech sounds (spectral context effects). Similarly, temporal characteristics of surrounding sounds can bias categorization of target speech sounds (temporal context effects). The literature features many individual reports of listeners experiencing these context effects, but what do these results mean across studies? If a listener exhibited a large context effect in one experiment, is that suggestive of him/her exhibiting a large context effect in a different experiment (i.e., general sensitivity to acoustic context) or not (i.e., results limited to certain stimuli / acoustic domains)? Here, I will take an individual differences approach to spectral and temporal context effects, evaluating their predictive power within and across domains, and how this might inform future work in these areas.
The changing social context of speech perception: Comparisons across age and time
Authors: Munson Benjamin
Published: April 2019

Beliefs about talkers' social-group membership affect how listeners perceive their speech: listeners identify phonemes differently depending on whether they believe that the talker was a man or a woman (Strand and Johnson, 1996; Munson, 2011), whether the talker was young or old (Drager, 2011), and whether the talker is gay or straight (Mack and Munson, 2012). These social influences are thought to reflect knowledge of social norms associated with categories such as gender, age, and sexuality. Social norms themselves are subject to change. For example, attitudes toward gay and lesbian people have changed dramatically in the past 15 years. For example, a strong majority of young adults now report having a positive view of sexual minorities. This talk reports on ongoing studies in our lab that have examined whether changes in social norms about gender and sexual orientation are associated with changes in how talkers' gender and sexual orientation affect listeners' speech perception (Obeda and Munson, 2018; Obeda et al., 2018). We have found robust differences between archival data from our lab from 2003 and both older and younger listeners tested in 2018. This talk will discuss the implications of these findings for models of speech perception more generally.
A uniform theory of diffraction formulation for acoustic radiation modes
Authors: Goates Caleb B. , Sommerfeldt Scott D. , Blotter Jonathan
Published: April 2019

Acoustic radiation modes have recently regained the attention of the literature, with applications ranging from active structural acoustic control to acoustical holography. Typically the calculation of these modes requires boundary element methods for all but flat plate and full sphere geometries. This paper presents a radiation mode formulation for cylindrically curved structures with small curvature, based on the uniform theory of diffraction. This formulation shows promise, as it produces analytical expressions for the radiation resistance matrix, leading to computationally efficient radiation mode calculation. Radiation modes are shown for cylindrically curved plates, and the calculation of sound power with these modes is compared to that calculated using boundary element methods. The extension of this formulation to other curved structures is discussed.
Far-field acoustic subwavelength imaging and edge detection
Authors: Ma Chu , Fang Nicholas X.
Published: April 2019

The resolution of far-field acoustic imaging is limited due to the loss of the evanescent field that carries subwavelength information. In this work, we report on the design and experimental realization of an acoustic far-field subwavelength imaging system based on a transmitting/receiving pair for wave vector filtering and conversion. In the near-field, the transmitter is composed of a resonator array for pre-filtering the evanescent wave, and an acoustic phase grating for converting the filtered evanescent wave into propagating wave. In the far-field, a receiver that is spatially symmetrical to the transmitter is used to convert the propagating wave back to evanescent wave and perform post-filtering. By tuning the resonance frequency of the resonator array and period of the phase grating, different spatial frequency bands can be separated and projected to the far-field. Far-field imaging and edge detection of subwavelength objects are experimentally demonstrated. The proposed system brings new possibilities for far-field subwavelength wave manipulation, which can be further applied to medical imaging, nondestructive testing, and acoustic communication.
Data-driven approaches for damage-type classification in vibrating square plates
Authors: Flynn Tyler J. , Dowling David R.
Published: April 2019

Acoustic radiation from a mechanical structure due to broadband forcing is inherently dependent on the structure’s material, geometry, boundary conditions, and mechanical status. Measurements of this acoustic or vibrational response can be used to detect mechanical changes (i.e., damage) when compared to known baseline measurements of the structure. Often, however, knowledge of the type of damage is useful for subsequent considerations. Even for relatively simple structures, like flat plates, the lack of simple solutions to problems involving localized damage makes analytical treatments challenging. This is further complicated since the location and severity of damage are typically unknown a priori. We present a data-driven approach for classification of various forms of damage—including cuts, localized mass changes, delamination, and boundary changes—in a vibrating clamped square plate. Frequency response curves are generated using FEA of a 30-by-30-by-0.3-cm aluminum plate with various types and severity of damage. Features (including changes in peak-locations, -amplitudes, and -widths compared to baseline) are extracted and used to train classifiers, with performance quantified using auxiliary test data. Comparisons are made between classifier types, including nearest neighbor methods, discriminant analysis, and support vector machines. [Work supported by NAVSEA through the NEEC and the US DoD through an NDSEG Fellowship].
Mandarin Chinese consonant production of patients with cleft palate
Authors: Yin Heng , Wang Xi , Guo Chunli , LI Jingtao , Li Yang , Shi Bing
Published: April 2019

Eighteen Mandarin Chinese consonants were recorded from 259 patients with cleft palate in a /CV/ context. The age of participants ranged from 8 to 40 years old. Participants had five types of cleft palate: submucous cleft palate, hard and soft cleft palate, unilateral complete cleft palate, bilateral complete cleft palate, and congenital velopharyngeal insufficiency. All consonants were transcribed by speech-language pathologists. Results showed that the accuracy of consonant production was significantly affected by the type of cleft palate, consonant category, and their interaction. The correctness of consonant production ranged from 45.8% for the type IV cleft palate (e.g., BCCP) to 71.5% for Submucous cleft palate. In particular, for the manner of articulation, nasals had significantly higher accuracy than stops, fricatives, and affricates, while for the place of articulation, palatal and labial sounds were problematic with low accuracy. In addition, the errors of consonant production, such as replacement, compensation, and omission, were also dependent on the type of cleft palate and consonant category and their interaction.
Efficacy of two speech-perception training methods for aided listeners with mild-to-moderately-severe age-related hearing losses
Authors: Miller James D. , Watson Charles S. , Kidd Gary R.
Published: April 2019

Preliminary analyses of interrelations among variables that correlate with measures of speech perception by aided listeners with mild-to-moderately-severe age-related hearing loses are described. The SPATS Group of nearly 120 hearing-aid users was trained in quiet and noise to identify syllable-constituents and to identify words in simple sentences. The Listen Group of about 60 aided listeners listened for an equal amount of time to recorded narratives. All were given audiometric, working memory, intelligence tests, a battery of psycho-acoustic tests, and a battery of speech-perception tests prior to training. The audiometric and speech perception tests were repeated after training and again after a 3-month retention period. Prior to training, there were large individual differences speech perception scores that could only be partially accounted for by the severity of audiometric loss. Training appears to be more effective for the SPATS Group than for the Listen Group. While improvements with training were generally modest, those who were very good or very poor initially tended to show little or no improvement, while those with middling scores tended to show more improvement. Sentence scores are highly correlated with syllable-constituent scores and with the use of context, and the use of context is correlated with working memory. (Miller and Watson are stockholders in communication Disorders Technology, Inc., and may profit from sales of some the software used in this study.)
The effect of talker variability on word recognition under cochlear implant simulation
Authors: Tamati Terrin N. , Baskent Deniz
Published: April 2019

Normal-hearing (NH) listeners have been shown to be less accurate and/or slower to recognize spoken words when the talker changes from trial to trial, compared to when the talker remains the same. Less is known about the effect of talker variability on cochlear implant (CI) users, who display a limitation in talker perception. As a first step, the current study investigated how limited talker information via CI simulation influences word recognition. In two experiments, NH listeners completed a word naming task in different talker conditions (single (ST), multiple female (MT-F), and multiple female/male (MT-M)) and simulation conditions (12, 8, and 4 vocoder channels). An effect of talker variability was observed, but only when talker differences were maximized. Listeners were less accurate, but not slower, at recognizing words under the MT-M condition, compared to ST and MT-F conditions. Talker variability effects did not vary by the simulation condition. These results are consistent with previous studies with NH listeners, showing similar performance in conditions where talker changes were not detected but talker differences were large. Taken together, these findings suggest that limitations in talker perception for NH listeners under CI simulation, and potentially CI users, alters the perceptual strategy for recognizing words under multiple-talker conditions.
Whole word scoring versus phoneme error scoring for audiological word recognition testing
Authors: Goshorn Edward L. , Goshorn Jennifer , Arnoult Jennifer
Published: April 2019

Conventional audiological word recognition testing uses whole word scoring for errant responses resulting in a percent correct score. This approach is found to be lacking in diagnostic utility. Recently, phoneme error scoring was suggested as a supplement to whole word scoring in attempt to improve diagnostic utility but is also limited in that it is highly correlated with the whole word score. This project examined the use of phoneme error scoring that applies an exponential equation to the type and the number of phoneme errors yielding a score that may be compared to absolute hearing sensitivity loss as measured by conventional audiograms. Because the number of words used in audiological word recognition varies, a correction for the number of stimuli is applied. Archival data, case study data, and simulated cases were used to evaluate and compare the diagnostic utility of three scoring approaches for errant responses: whole word, total phoneme errors, and an exponential phoneme error score (EPES) that weights consonant and vowel errors differently: EPES = number of phoneme errors times 2number of consonant errors + 10number of vowel errors. The case study and simulated results were used to evaluate the utility of each scoring approach.
The (minimal) influence of perceived age on the perceived gender of children's speech
Authors: Munson Benjamin
Published: April 2019

The acoustic characteristics of boys and girls' speech resemble adult norms for men and women, respectively, early in life. Moreover, the extent to which a child's speech resembles the adult norms for their biological sex is related to other measures of the extent to which their gender development meets cultural norms [e.g., Perry et al., J. Acoust. Soc. Am. 109 (01); Munson et al., J. Acoust. Soc. Am. 137 (15); and Beaulieu et al., J. Acoust. Soc. Am. 143 (18)]. The acoustic cues to gender in children's speech are distributed throughout the speech signal. Hence, the most common method to determine the attainment of gendered speech is by gathering perceptual ratings of gender typicality. In this study, we examine whether ratings of the gender typicality of children's speech are affected by ratings of another potentially salient attribute that speech acoustics convey: speaker age. We conducted an experiment in which perceived gender and perceived age ratings were collected for the single-word productions of 57 5–13 year old children examined by Beaulieu et al. (18) and brief spoken narratives by the same children. Preliminary results suggest that the effects of talker sex are robust when both actual age and perceived age are controlled statistically.
Photomicrography of the middle ear ossicles
Authors: Kist Matthew , Scheifele Peter M.
Published: April 2019

I removed temporal bone sections from human cadavers with the help of my colleagues. From there, I utilized a Dremel tool to access the otic capsule and remove the malleus, incus, and stapes from each section. Not all attempts were successful due to the fragile nature of these bones. I extracted a total of 5 stapes, an incus, and 2 mallei in total. These bones were photographed using photomicrography: a 35 mm film camera attached to a microscope. The purpose of this research is to provide high quality images of the middle ear ossicles for educational purposes and learning tools. The ossicles will also be present in addition to the poster for individuals to hold and accurately grasp the size of these bones.
Trans-dimensional geoacoustic inversion and uncertainty quantification for SBCEX17 data
Authors: Dosso Stan E. , Dettmer Jan , Holland Charles W. , Belcourt Josee , Bonnel Julien , Tollefsen Dag , Knobles David P.
Published: April 2019

This paper presents an efficient and general approach to Bayesian inversion and uncertainty quantification for seabed geoacoustic profile estimation. The model-selection problem of estimating an appropriate seabed parameterization is addressed with trans-dimensional (trans-D) inversion via reversible-jump Markov-chain Monte Carlo, which samples probabilistically over the number of layers. An efficient proposal density for parameter perturbations is based on using a linearized approximation to the posterior probability density, applied in principal-component (PC) space where the (rotated) parameters are uncorrelated. The acceptance rate of perturbations and birth/death steps is improved by parallel tempering, based on a series of interacting Markov chains with successively tempered (relaxed) likelihoods. The PC proposals are adapted individually to the tempering of each Markov chain. The data-error model is based on the assumption of multivariate Gaussian errors with correlations represented by an autoregressive process. The parameters of zeroth- and first-order autoregressive error processes are sampled trans-dimensionally to avoid over- or under-parameterizing the error model. The approach is illustrated for three data sets from the 2017 Seabed Characterization Experiment (SBCEX17), including broadband seabed reflection coefficients; dispersion of water-borne acoustic modes, resolved by warping analysis; and ship noise recorded at a bottom-mounted horizontal array of hydrophones.
Employing geometric pattern discovery techniques for sonar target recognition
Authors: Sen Gupta Ananya , Kirsteins Ivars P.
Published: April 2019

Automated sonar target recognition suffers from linear superposition of acoustic color features, which need to be precisely disambiguated to correctly identify a target of the specific composition and geometry. Most target acoustic color images exhibit feature overlap between environmental reverberation as well as reflections due to target geometry, and elastic waves that are representative of the material composition of the target. From a signal processing perspective, this is essentially mitigating and disentangling interference from two highly competing yet hard-to-predict sources: reflections from the environment and reflections due to the target geometry, which represent different physical phenomena with distinct geometric patterns. We will present recent results in feature selection and interference mitigation employing Gabor wavelets to separate target acoustic color features due to elastic wave orbits from interfering features due to the target geometry and environmental effects. We will provide results from simulations as well as experimental field data and discuss the trade-offs in feature representations employing acoustic color and those that also include the phase information. Finally, we will discuss how this type of feature extraction can be used to discover and create robust priors for Bayesian inference networks for learning salient target features.
Sparse Bayesian learning beamforming combined with short-time Fourier transform for fault detection of wind turbine blades
Authors: Pan Xiang , Cheng Zefeng , Zheng Zheng , Zhang Yehui
Published: April 2019

Wind energy is one of the important renewable energy resources. The wind turbines need to be checked every now and then to enhance security. The rotor blade of the wind turbine can be damaged due to long-term running in harsh environments and complex vibrations resulting in the crack of blade. For detection of the blade faults, the sparse Bayesian learning (SBL) beamforming (BF) is implemented to the acoustic data received by a microphone array on the ground for signal enhancement. The direction of arrival of the abnormal sound can be estimated with high resolution meanwhile interferences, such as noise emitted by cooling fans, can be suppressed by the low sidelobes provided by the SBL-BF. After the Short-Time Fourier Transform (STFT) is carried out over the enhanced signals, it is seen from the time-frequency spectrum that the abnormal sound appears with an approximate 6-s cycle. By detecting the cyclical characteristics, one can decide whether there is or not the blade fault. A real-time processing system for detection of the blade faults underwent a number of tests in a coastal plain, a hilly area, and the Xinjiang Plateau. The test results have demonstrated the effectiveness of the blade fault detection framework.
Azimuthal dependence of the acoustic field in a year long Canada Basin Acoustic Propagation Experiment
Authors: Badiey Mohsen , Lin Ying-Tsong , Pecknold Sean , Ballard Megan S. , Sagers Jason D. , Turgut Altan , Colosi John A. , Worcester Peter F. , Dzieciuch Mathew
Published: April 2019

As in the mid-latitudes, the variability of the oceanography in the arctic ocean causes azimuthal dependent acoustic fields induced by the environmental parameters, such as the variable sound speed profile and bathymetry. Preliminary analysis of a year-long experimental data from “deep-to-shallow” and the “shallow-water” Canada Basin Acoustic Propagation Experiment (SW CANAPE) shows strong azimuthal variability of broadband signals recorded on 11 spatially distributed acoustic receiver arrays on the Chukchi shelf from September 2016 to October 2017. Particular attention is paid on geotimes pertaining to the variable sound speed profiles around the dynamic shelf-break region. Although acoustic modeling of the propagation requires a physics based ocean model for a complete modeling exercise, preliminary determination of the azimuthal behavior of broadband propagation is conducted using multiple two-dimensional Parabolic Equation (Nx2D) with the collected oceanographic data. Calculations for long-range, as well as short-range, source-receiver pairs in the SW CANAPE data show that azimuthal variabilities occur frequently and are related to the spatial and temporal characteristics of signal dispersion for different range and geotime scales. [Work supported by ONR.]
Forty-year review of developments in underwater acoustic modeling
Authors: Etter Paul C.
Published: April 2019

This is the sixth paper in a series of reviews presented at eight-year intervals starting in 1979 [J. Acoust. Soc. Am. 65, S42 (1979); 82, S102 (1987); 97, 3312 (1995); 114, 2430 (2003); 129, 2631 (2011)]. All surveys covered basic acoustic models and sonar performance models. Basic acoustic models included 143 propagation, 29 noise, and 32 reverberation models. Propagation models were categorized according to ray theory, multipath expansion, normal mode, fast field, and parabolic approximation formulations; further distinctions were made between range-independent and range-dependent solutions. Noise models included ambient noise and beam-noise statistics models. Reverberation models included cell and point-scattering formulations. The 44 sonar performance models included active sonar models, model operating systems, and tactical decision aids. Active sonar models integrated basic acoustic models, signal-processing models, and supporting databases into cohesive operating systems organized to solve the sonar equations. Model operating systems provided a framework for the direct linkage of data-management software with computer-implemented codes of acoustic models. Tactical decision aids represented a form of engagement-level simulation that blended environmental and sonar performance information with tactical rules. The overall inventory increased by 5 models per year; historical references are maintained in the fifth edition of Underwater Acoustic Modeling and Simulation.
Analytic solution to a waveguide featuring caustics and shadow zones
Authors: Worthmann Brian M.
Published: April 2019

Exact solutions to waveguides are useful tools for validating numerical waveguide models. In this paper, a modal solution to an unbounded waveguide with a range-independent but depth-dependent profile is described. The sound speed profile utilized is a symmetric, piecewise n2-linear profile matched above and below to a homogenous half-layer with density and sound speeds that prevent any reflections at the interface. In this environment, caustics and shadow zones are formed. A nearly exact solution to this environment could help improve other numerical methods' accuracy near caustics and shadow zones. In this mathematical analysis, both proper (trapped) and improper (leaky) modes are included. Arbitrarily high frequencies are permitted through the use of numerically well-conditioned approximations to Airy functions, particularly for the dispersion relations and mode-shape evaluations. The proper (real) and improper (complex) modal eigenvalues are found approximately, with root-finding algorithms used for eigenvalues near cut-off to improve the approximation. Mathematical details are presented along with a brief discussion of how well a few common numerical solvers agree with the analytic solution derived.
Preliminary soundscape observations from a Colombian humpback whale breeding ground before port construction
Authors: Seger Kerri , Perazio Christina E. , Gonzalez Valeria , Luna-Acosta Andrea , Botero Natalia
Published: April 2019

The Gulf of Tribugá in the Colombian Pacific is still relatively undisturbed. No road access between villages nor from major urban areas exists. Small boats and walking beaches at low tide serve as the main transportation conduits. In this breeding ground for humpback whale Stock G, small-scale artisanal and shrimp fisheries and whale-watching activities support the livelihood of local communities but may already interfere with biological communication systems. Once a proposed international port is built anthropogenic pressure is expected to increase. Baseline information is key to understand the Gulf's current acoustic state and to document the best approximation of its practically pristine state. An ecological Acoustic Recorder (EAR, Oceanwide Science Institute) was deployed between the largest town (about 2000 residents) and the southern boundary of the Utria National Park marine reserve from October to December, 2018. Also, opportunistic over-the-side recordings from July to September, 2018, provided point surveys at a greater spatial resolution during peak humpback whale breeding season. Results include the first acoustic catalogue of the area and a preliminary understanding of important bandwidths for future monitoring and current contributions of small vessels to the soundscape.
The spectrum of concrete: Material research and experimentation expanding previous sound lab results for various acoustical environments
Authors: Butko Daniel
Published: April 2019

This paper presentation continues progress of an active multiphase acoustical research project emphasizing implementation of prototypical concrete systems in multiuse spaces to transform unhealthy learning environments. Building upon research results shared during the December 2017 and November 2018 ASA paper presentations, various admixtures/additives are being explored as viable ingredients to develop concrete mixtures capable of decreasing excessive reverberation and flutter echo while increasing clarity and speech intelligibility. Faculty and students, working in both physical and digital realms with industry partners, are analyzing and validating consequences of manipulating materials for resultant acoustical criteria. The work presented here showcases research and development of how concrete can be processed, shaped, surfaced, and implemented into full-scale built form to provide scholarly merit applicable in/with similar spaces and/or functions.
Arabian horse vocalization: A brief look at romance
Authors: Browning David , Herstein Peter , Scheifele Peter M.
Published: April 2019

Arabian horses are an expressive breed. It has been determined that domestic horse whinnies have two unrelated fundamental frequencies, termed F(0) and G(0), with their harmonics such as F(2), etc. F(0) can be connected to arousal, while G(0) to mood. Fifteen Arabian whinnies during quiet barn conditions were analyzed to determine typical calm F(0) and G(0) values. A limited number of whinnies were than obtained from a corralled stallion during his recognition, anticipation, and culmination of a mare being brought to nuzzling distance on the other side of the fence. The spectra of his prenuzzling whinnies are as might be expected but after the culmination he gives a loud whinny with a complex structure that is not totally understood.
Optical mean irradiance change for inference of focused-ultrasound-induced strain and thermal expansion in tissue-like materials
Authors: Holt R. Glynn , Vakili Ali , Hollmann Joseph L , DiMarzio Charles A.
Published: April 2019

Inferring material properties in scattering media, especially tissue, is a commonly applied method for detecting flaws or abnormalities. Hybrid acoustic/optic methods are often employed to overcome the limitations inherent in one or the other. Such hybrid methods have achieved great success in imaging various features (mechanical or optical properties) at a variety of spatial scales down to the sub-cellular. Here, we seek to develop an intermediate resolution method of detecting changes in material properties that is robust, inexpensive, and potentially capable of real-time analysis. We exploit the ability of the time-averaged absorption of focused ultrasound to induce changes in the optical index of scattering materials. By combining simulations with experiments, we demonstrate that the optical mean irradiance change measurement is capable of revealing time-dependent index changes. We are able to separate the contributions of both thermal expansion and radiation force deformation in the correlation signal. Potential applications of this technique will be discussed.
Deep-learning framework and acoustic reflector for improved limited-view and sparse photoacoustic tomography
Authors: Ngnie Kamga Irvane , Guan Steven , Chitnis Parag V.
Published: April 2019

Photoacoustic imaging is a hybrid imaging modality that relies upon optical absorption of pulsed light and subsequent thermoelastic generation of ultrasound. The detection of the induced acoustic waves outside the tissue enables image reconstruction. A major challenge encountered in photoacoustic tomography (PAT) lies in the inability to acquire complete projection data from the region of interest due to both the limited view and sparsity of available ultrasonic sensors. The resulting images are characterized by severe artifacts and poor quality. In this work, we examined the utility of incorporating an acoustic reflector to address the limited view problem and to train a convolutional neural network (CNN) to improve PAT image reconstruction from sparsely sampled data. Photoacoustic wave propagation was simulated in MATLAB using the k-Wave toolbox. We compared the performance of a sparse linear transducer array (with and without reflector) to that of a circular transducer array. The structural similarity index (SSI) was used as a metric for evaluating image quality. The combination of a curved reflector and artifact-removal using a CNN improved the quality of PAT images from the linear configuration. The resulting mean SSI value (0.859) was comparable to that achieved using the circular transducer array (0.926).
Hot topics in computational acoustics
Authors: Wilson D. K.
Published: April 2019

As reflected by the formation of a new Computational Acoustics Technical Specialty Group in the ASA, computational methods attract acoustics researchers and practitioners across the spectrum of the current ASA Technical Committees. This presentation samples several prominent hot topics in computational acoustics: (1) high-resolution, three-dimensional solutions for sound fields in the ocean, atmosphere, and indoor spaces, (2) time-domain treatments of dissipative processes and reactive boundary conditions, (3) machine learning and other data-driven surrogate models trained with more computationally intensive physics-based models, and (4) characterization of uncertainty in computations and its quantification through methods such as adaptive sampling and polynomial chaos.
Automated Mandarin tone classification using deep neural networks trained on a large speech dataset
Authors: Tyler Jeramey , Zou Huang , Zhou Helen , Su Hui , Braasch Jonas
Published: April 2019

A tonal language is one in which the speaker’s intonation modifies the meaning of a word. In this work, we perform a rigorous analysis of intonation changes, or pitch contours, produced by native Mandarin speakers to predict the tone-contour type. Pitch contours are estimated using a number of different methods, also measuring each contour’s Mel-Frequency Cepstral Coefficients (MFCCs). The dataset used was autonomously generated from the Aishell open-source Mandarin speech corpus. Each sample was aligned with its transcript using Montreal Forced Alignment and segmented into individual words. The resulting corpus covers 11 topic domains, spoken by 400 individuals. Separate development, training, and testing datasets are created to ensure the integrity of our results. Pitch contours and their MFCCs are exposed to a number of machine learning techniques including clustered, regression, and traditional Deep Neural Network (DNN) approaches. MFCCs are additionally processed using convolutional neural networks. The models are used to predict the corresponding tone for a contour. Our work seeks to determine which intonation representations perform optimally for machine learning tasks. The tool is used to provide audio and visual feedback to learners of tonal languages. [Work supported by RPI Seed Grant and CISL].
Referee whistles Part I—Permissible exposures indoors
Authors: Jerome Trevor W. , Flamme Gregory , Murphy William J.
Published: April 2019

Sound from referee whistles at sporting events is usually relatively short in duration (<250 ms) but generated at relatively high levels (>110 dB SPL). Damage risk criteria (DRC) that categorize potentially harmful sounds are usually meant for either continuous or impulsive noise. These types of whistle sounds are better categorized as impulsive. Measurements were taken of a trained referee using a sample of commercially available whistles in a controlled environment. One microphone was placed at the ear of the referee, and another was placed 1 m in front of the referee. Whistle signals were analyzed with a maximum duration of 450 ms, which would be typical of a sporting event. DRC for these impulsive sounds have been investigated using DRC of A-weighted 8-h energy (LeqA8), and the warned and unwarned conditions of the AHAAH model. Depending on the risk model used, the numbers of permissible exposures was as low as zero and extended above.
Turn up the volume: Speech perception in noise for bilingual listeners
Authors: Skoe Erika
Published: April 2019

Bilinguals, compared to monolinguals, have been reported to have stronger neural representation of the fundamental frequency (F0) of speech, as measured by the frequency-following response (FFR). In monolinguals, stronger FFRs to F0 have been associated with better speech perception in noise (SPIN), suggesting that bilinguals should outperform monolinguals on SPIN tests. However, the opposite is the case: bilinguals generally underperform monolinguals. To explain such findings, Krizman et al. (2017), proposed that the bilingual brain might turn up the volume on the neural representation of sound to compensate for reduced SPIN. The current work considers this possibility using a combination of FFR and SPIN data. The Revised Speech in Noise test was administered at signal to noise ratios (SNRs) of 0 and 3 dB to young adult monolinguals (n = 17) and early bilinguals (n = 26). Unlike the monolinguals, the bilinguals showed a drop in performance when the SNR dropped. Within the bilingual group, poorer SPIN performance correlated with stronger neural responses to F0, suggesting that sensorineural areas are recruited to increase the neural gain of the acoustic representation in a manner that inversely correlates with speech comprehension. These findings give new insight into the brain-behavioral relationships for the neural encoding of sound.
Effects of aging on voice emotion recognition in cochlear implant users and normally hearing adults listening to spectrally degraded speech
Authors: Cannon Shauntelle , Chatterjee Monita
Published: April 2019

Voice emotion recognition declines with age in normally hearing (NH) adults. However, the effects of aging on voice emotion recognition in NH listeners with spectrally degraded stimuli are neither known nor the effects of aging on adult cochlear implant (CI) users. This study explored age-related effects on voice emotion recognition in NH adults listening to spectrally degraded speech and aimed to compare these changes to age-related changes in adult CI users’ voice emotion recognition with unprocessed speech. Participants listened to 12 emotion-neutral sentences, each spoken with 5 emotions (happy, sad, scared, angry, and neutral) by a male and female talker. Participants identified which emotion they heard while listening to sentences that were either unprocessed or CI-simulated. Preliminary results indicate declines in overall percent correct scores and increased reaction time with both age and increasing spectral degradation in NH adults. Results also suggest age-related effects on percent correct scores and reaction times within the CI group alone. These results have important implications in the aging population of adults with NH and with CIs because limitations in the quality peer to peer interactions have been associated with a decrease in perceived quality of life. [Work supported by R01 DC014233 and P20 GM109023.]
Impact of viscoelastic damping properties on vibration response of scale models
Authors: Beck Benjamin
Published: April 2019

There are many industries that utilized scale models to test the behavior of systems before building full-size structures, such as aircraft, spacecraft, and marine vehicle design. While vibration and acoustic response may not be the only quantities of interest when testing scale models, scale models can be utilized to predict full-scale acoustic behavior. When damping treatments are to be applied to full-scale systems, there will also be a need to apply these treatments to the scale models. Typically, these damping treatments use viscoelastic materials due to their high loss factor. However, since the stiffness and loss factor of viscoelastic materials change significantly with frequency, viscoelastic damping treatments will not behave consistently between model- and full-scale. This work shows the impact of using the same viscoelastic damping treatment on scale models as designed for full-scale systems. As a test case, a model of a thin vibrating plate will have a constrained layer damper applied on one surface. The total surface velocity response of a full-scale and model-scale finite element plate with a viscoelastic constrained layer damper is compared. Methods of designing viscoelastic materials for scale-models will also be presented.
A comparison of training effects on non-native tone sandhi production between American English and Cantonese speakers
Authors: LI Bei , Yang Yike , Chen Si , He Yunjuan
Published: April 2019

Previous studies suggest that productions of Mandarin tone sandhi by both American English speakers and Cantonese speakers were perceived more native-like after a laboratory perceptual training, whereas little is known about the effects of tonal or non-tonal backgrounds. Ten Cantonese-speaking trainees and ten American English-speaking trainees matched in age and Mandarin proficiency were recruited to the pre- and post-training recording sessions. Elicited with audio and visual stimuli, participants naturally produced disyllabic real and wug words where the two Mandarin tone sandhi rules (T3 + T1/T2/T4 sandhi and T3 + T3 sandhi rules) should be applied. In total, 7680 sandhi syllables obtained from two sessions were perceptually evaluated by two phonetically trained Mandarin-speaking raters on a 101-point scale. Statistical results indicated that native tonal/non-tonal backgrounds influence Mandarin learners’ improvement in the two sandhi rules differently. The Cantonese trainees outperformed the English trainees in the sandhi of T3 + T1/T2/T4 before training, and the two groups had statistically comparable performance after training, although both groups exhibited significant improvement. For the sandhi in T3 + T3, improvement occurred for the Cantonese trainees while not for the American trainees after training, suggesting that the successful learning of phonological T3 sandhi rule may require a tonal background.
New tools to auralize simulation results with EASE 5.0
Authors: Behrens Tobias , Wazaefi Khaled , Ahnert Wolfgang
Published: April 2019

The new software package in EASE allows the production of binaural files to check the quality of the simulation results and to make these results audible for music or speech samples in real time. Also, tests with head trackers have been made. Since 5 years, the software allows generating B-format files of second order. To reproduce sound fields based on these 9 files, a sound lab has been built. This lab will be represented and explained. A post-processing software for EASE allows to reproduce not only the calculated simulation files but in comparison also measured files by using the microphone Ambeo VR. Additionally, VR glasses generate realistic 3D-visuals, in the same model as used for acoustic simulation. That way realized acoustic treatments in the room become visible and audio-visual representations are possible. Results for comparison between simulated rooms and measured real rooms will be discussed.
Detection and classification beaked whale vocalization calls based on unsupervised machine learning algorithm
Authors: Li Kun , Sidorovskaia Natalia
Published: April 2019

Currently, passive acoustic monitoring (PAM) becomes a more useful tool to record and analyze cetacean’s calls, such as beaked whales and sperm whales. To study the regional population variability of beaked whales in the northern Gulf of Mexico, the acoustic data were collected by the Littoral Acoustic Demonstration Center-Gulf Ecological Monitoring and Modeling (LADC-GEMM) consortium at three different sites in the vicinity of the 2010 oil spill site. One of the challenging goals is an identification of different species of beaked whales autonomously in large datasets. A multi-stage detector was developed to detect and classify the beaked whale species. The data processing results show that two major species of beaked whales (Cuvier’s and Gervais’) were acoustically observed in the study area. The results suggest that Cuvier’s beaked whales tend to be more active at the deeper sites (about 1500 m) and Gervais’ beaked whales prefer the shallower site which is about 1000-m deep. The results highlight the need for high spatial resolution acoustic monitoring and support the ecological niche hypothesis. The results also show that the acoustic activity for two major species of beaked whale have distributed throughout the day, and beaked whales do not exhibit seasonal preference for the Mississippi Valley site. The important new insights into the population structure and habitat preferences of different species of beaked whales in the northern Gulf of Mexico were obtained.
Detection of dolphin burst-pulses off Cape Hatteras, North Carolina, correlated to oceanographic features
Authors: Lockhart Stephen B. , Muglia Mike , Dubbs Lindsay
Published: April 2019

To assess the ecological impact of extracting energy from the Gulf Stream, the University of North Carolina Coastal Studies Institute has deployed a mooring on the continental slope off Cape Hatteras at a depth of 230 m, equipped with an Acoustic Doppler Current Profiler, CTD, and a hydrophone. Analyzing 16 months of data, we automatically detected dolphin “quacks” or “barks”, using two detectors. First, we used a pitch detector to automatically detect such signals over a specified range of pitch values. Next, we used a matched filter approach. All detections were reviewed manually to eliminate false alarms. For these signals, we found a strong correlation with temperature and salinity at the bottom; the vocalizations were detected when the water was relatively cooler and fresher. As the Gulf Stream meanders seaward of the mooring site, the temperature and salinity there both decrease. Since this cooler water is higher in nutrients, one explanation for the correlation is that the marine mammals are attracted to this more productive water. Alternatively, the meandering Gulf Stream may influence either (a) the acoustic propagation around the mooring and/or (b) the acoustic noise around the mooring. Evidence for each alternative will be presented.
Understanding detectability variations for density estimation of marine mammals
Authors: Guilment Thomas , Sidorovskaia Natalia , Li Kun , Tiemann Christopher
Published: April 2019

Passive acoustic monitoring (PAM) makes it possible to obtain reliable observations of marine mammals and to estimate the population density based on detected acoustic cues. PAM surveys offer higher accuracy density estimates than traditional visual surveys as long as the survey design is adequate and the probability of detection is reliably measured. The probability of detection depends on regional bathymetry, the season, the PAM system used, the detection algorithm, and the animal’s acoustic apparatus. To improve the accuracy of the density estimation, this study focuses on understanding the relationship between the probability of detection of beaked whales and the detection algorithm used. The study utilizes the PAM data collected by fixed moored stations in the Gulf of Mexico in 2015 and 2017. The detectability function derived from experimental data is compared with the one obtained by modeling for two species of beaked whales (Cuvier and Gervais whales). The results will provide the guidance when and how modeling can be used to obtain reasonable estimates of the probability of the detection function. [Work supported by a grant from The Gulf of Mexico Research Initiative.]
Effects of click rate on bottlenose dolphin auditory brainstem response signal-to-noise ratio
Authors: Finneran James J. , Mulsow Jason , Burkard Robert F.
Published: April 2019

Maximum Length Sequence (MLS) and Iterative Randomized Stimulation and Averaging (I-RSA) methods allow auditory brainstem response (ABR) measurements at high stimulus rates; however, it is not clear if high rates allow ABRs of a given signal-to-noise ratio (SNR) to be measured in less time than conventional averaging at lower rates. In the present study, ABR SNR was examined in six bottlenose dolphins using conventional averaging at rates of 25 and 100 Hz and the MLS/I-RSA approaches from 100 to 1250 Hz. Residual noise in the averaged ABR was estimated using root-mean-square values of the: waveform amplitude following the ABR, waveform amplitude after subtracting two subaverage ABRs, and amplitude variance at a single time point. For all approaches, residual noise decreased with the increasing measurement time. For a fixed recording time, SNR was highest at rates near 500 Hz, but optimal SNRs were only a few dB higher than that for conventional averaging at 100 Hz. Nonetheless, small improvements in SNR could result in significant time savings in reaching criterion SNR. The time savings allowed by the MLS and I-RSA methods will be discussed for both mean and individual data. [Work supported by U.S. Navy Living Marine Resources Program.]
Acoustic holography for calibration of ultrasound sources and in situ fields in therapeutic ultrasound
Authors: Sapozhnikov Oleg A. , Kreider Wayne , Tsysar Sergey A. , Nikolaev Dmitry A. , Khokhlova Vera A.
Published: April 2019

Therapeutic ultrasound sources, which are typically piezoelectric transducers, are intended to deliver known acoustic pressures to targeted tissue sites. Each transducer vibrates in a unique way and radiates a corresponding 3D ultrasound field. Accordingly, transducer vibrations should be known accurately in order to characterize the pressures delivered to the patient. Acoustic holography is a technique that relies on hydrophone measurements to reconstruct a source hologram that characterizes transducer vibrations [Sapozhnikov et al., JASA, 138(3), 1515–1532 (2015)]. In this way, a hologram is a signature of each transducer that can be monitored over time for quality assurance. Using holography-defined source boundary conditions, numerical forward projection of the ultrasound field based on the nonlinear wave equation can be used to accurately predict in situ temperatures and pressures in heterogeneous media for treatment planning. As such, acoustic holography goes beyond simple hydrophone scans and is uniquely suited to meet clinical needs for quantifying therapeutic ultrasound fields. In this paper, several examples of acoustic holography implementation are presented, including the characterization of single-element and multi-element flat and spherically curved sources working in linear and nonlinear regimes and in continuous and pulsed modes. [Work supported by NIH 1R01EB025187, R01EB007643, and R21CA219793; RFBR 17-02-00261 and 17-54-33034.]