bluuebunny/crossref_metadata_2025 huggingface dataset:
Embedded real-time processing of acoustic vector sensors using a lightweight open-source microcontroller
Authors: Leary Paul , Dobrokhodov Vladimir , Jones Kevin , Smith Kevin B.
Published: October 2018

This abstract is intended for the special session “Acoustic Vector Field Studies.” In this work, we will show our progress towards a low-power, lightweight, embedded data acquisition system and real-time signal processor for acoustic vector sensors, using an open-source microcontroller. Modern advances in low-cost, low-power “systems-on-a-chip” (SoC) provide unprecedented computational power, and some state-of-the-art devices are particularly well designed for acoustic signal processing applications. Here, we present the results of performance experiments, demonstrating the speed and accuracy of sampling and processing audio-frequency signals for a wide variety of signals and sampling regimes. We demonstrate trade-offs between sampling rates and resolutions for accuracy and speed at desired frequencies, and how these may be dynamically managed by autonomous systems. Finally, we will share some of our work towards real-time acoustic beamforming for use on autonomous vehicles.
Parabolic equation modeling of a seismic airgun array
Authors: Heaney Kevin D. , Campbell Richard L.
Published: October 2018

The numerical modelling of seismic airgun sources, with a specific emphasis on the impact of sound on the marine ecosystem, is a challenging problem. In this paper, the simplified range-independent iso-velocity problem set up as part if the International Airgun Modelling Workshop (IAMW), is solved using the Parabolic Equation (PE). The acoustic pressure and particle acceleration are computed including the arrival time series and source energy level in deci-decade bands for ranges spanning from 30m to 30 km. The particle acceleration is computed by taking the spatial gradient of the pressure on the PE computational grid. The two significant challenges this problem poses to the PE solution are the very large bandwidth (5-4500 Hz) and the computational accuracy required for time-series and particle acceleration computations. Each of the metrics outlined in the statement of the problem are computed and presented. In addition to computing the required fields, the 17-gun volumetric array is placed in a 3D ocean environment in deep water in the Gulf of Mexico, with peak pressure computed out to 30km and the band integrated Signal Energy Level (SEL) computed to 400 km.
Bottom scattering by a moving, narrowband source
Authors: Hefner Brian T. , Hodgkiss William S.
Published: October 2018

During the Target and Reverberation Experiment in 2013 (TREX13), two vertical line arrays were deployed and a mid-water source was towed past these arrays while transmitting 15-s long, mid-frequency CW tones. While the received signals exhibited the expected positive and negative Doppler shifts as the source moved toward and away from the arrays, a significant amount of energy was always present in the band between these two frequencies. This counterintuitive result is due to sound scattering from the seafloor in the vicinity of the source. This sound will experience a different Doppler shift and although it may be incident above the critical angle, it can scatter into propagating modes that can be received on the arrays. As opposed to wide-band reverberation where the energy received at a given time can be associated with an elliptical scattering patch, in this case the energy received at a given frequency can be associated with scattering from a hyperbolic scattering patch. A normal-mode reverberation model for this effect has been developed and is used to examine whether this data can be used to invert for the seafloor scattering strength at the TREX13 site. [Work supported by ONR.]
An experimental test of end-fire synthetic aperture sonar for sediment acoustics studies
Authors: Steele Shannon-Morgan M. , Lyons Anthony P.
Published: October 2018

Seafloor sediment acoustic returns are comprised of scattering from both the interface and sediment volume. At low-frequencies, volume scattering is often the dominant mechanism; however, direct measurements of this component have rarely been made, due to interface roughness biasing caused by large beamwidths. End-fire synthetic aperture sonar (SAS) can achieve narrower beamwidths by coherently combining multiple acoustic returns as a vertically oriented transmitter and/or receiver is moved towards the seafloor. Beam pattern simulations suggest end-fire SAS can reduce the beamwidth of a sonar by a factor of 6 with an array length of 100 wavelengths. Achieving these gains is dependent on the ability to resolve relative sonar motion to at least an eighth of a wavelength. This talk will present results from an end-fire SAS field trial. Results will include an analysis of beamwidth gains achieved during the end-fire SAS field test and methods to improve these gains by using the scattered field to refine sonar positions.
Studies on water column nutrient distribution and sound speed profile variations along coastal region of India
Authors: Santhanam Sakthivel M.
Published: October 2018

This study aim is to measure the water column nutrient and sound velocity variation along the coastal region of Poompuhar, Cuddalore, Mahabalipuram, Kalpakkam, Chennai and Pondicherry. Sound speed variation in the environment of the particular ocean depends on temperature, salinity, and pressure. Since temperature and salinity variations are large compared to pressure. In study locations the sound speed varies from 1445 to 1540m/s, temperature 27 to 290c and salinity 29 to 33psu. Water column nutrients like Nitrate, Nitrite, Phosphate, Silicate and Urea were analyzed to understand the physical and chemical concentration of study location. This nutrient has an inverse relationship with the temperature. Location-based nutrients analysis has been carried to identify the concentration each nutrients level in the particular location. The maximum concentration of nutrients observed in the study locations are silicate in Pondicherry (84%), Nitrite in Kalpakkam (4%), Nitrate in Cuddalore (16%), Phosphate in Chennai (6%), and Urea Poompuhar-2 (24%). The total suspended solids level in the water column is measured to identify the impact on the signal transmission in underwater. The higher value of TSS is observed in Cuddalore (0.15 mg/L).
Measurements of modal attenuation using broadband sources in the New England Mud Patch
Authors: Unrein Kerry , Potty Gopu R. , Miller James H. , Tollefsen Dag , Knobles David P. , Wilson Preston S. , Lin Ying-Tsong
Published: October 2018

Measurements of underwater acoustic signals were made on a bottom-mounted horizontal line array during the Seabed Characterization Experiment (SCEx) in the New England Mud Patch south of Martha’s Vineyard in about 70 meters of water. The signals were generated by SUS (Signals, Underwater Sound) charges detonated at various locations in the experimental area at a depth of 18 m, during nearly-isovelocity conditions. The broadband signals were analyzed for modal arrival time and amplitude using time-frequency techniques. Ratios of modal amplitudes at the different hydrophones were used to estimate the modal attenuation coefficients. Hence, these estimates are independent of any uncertainty in the frequency-dependent source level of the SUS charges. These coefficients are directly related to the depth-dependent sediment attenuation profile. A sensitivity study was performed to understand how the modes sample the different layers and provides estimates of resolution kernels. Posteriori error analysis provides averages and standard deviations for the estimate of sediment attenuation as function of depth. The frequency bands of interest range from 10 Hz to 200 Hz for modes 1 to 4. We will compare our estimates of sediment attenuation with historical measurements. [Work supported by Office of Naval Research.]
An overview of Murray’s Hodgson indirect contribution to the acoustical community as a mentor
Authors: Logawa Banda
Published: October 2018

During his more than 20 years of career as a professor at University of British Columbia, Murray Hodgson has inspired many of his previous students to pursue their career in various fields of acoustics, both in academia and industry. His undergraduate engineering course Acoustics and Noise Control was the first exposure to the vast world of acoustics for many of his former students. Furthermore, Murray has also supervised many students through their graduate studies. This paper will highlight Murray’s indirect contribution as a mentor by summarizing the current whereabouts of his former students who are now an active member of the acoustical community in North America and around the world.
Some contributions of Murray Hodgson to room acoustics modeling
Authors: Valeau Vincent , Picaut Judicaël , Foy Cedric
Published: October 2018

This presentation focuses on some of the many contributions of Murray Hodgson (1952–2017) concerning room-acoustic modeling. The concepts of sound field diffuseness and diffuse reflections have always been of major interest for Murray, his studies associating most of the time numerical modeling and measurements on scale models or real-scale rooms. His most cited paper [JASA 89, 1990] proposes to include diffuse surface reflections in ray-tracing simulations, and is a milestone in room acoustics prediction as most standard room-acoustic prediction softwares now include surface diffusivity. Another extensively cited paper [App. Ac. 49, 1996] discusses the applicability of diffuse field theory according to room shape and to absorption distribution and magnitude. The conclusions of this study are still greatly useful to researchers, students, and practitioners. Another important focus of Murray’s research has been the acoustics of « fitted » rooms (i.e., rooms containing many obstacles such as industrial workrooms, classrooms…), and was the topic of many of his papers. This presentation will review some contributions of Murray on this research topic.
Burst-pulses in East Greenland narwhals: Further evidence for unique, individual-specific vocalizations
Authors: Blackwell Susanna B. , Tervo Outi M. , Conrad Alexander S. , Heide-Jørgensen Mads P.
Published: October 2018

In August 2013–2017, narwhals from Scoresby Sound, East Greenland, were instrumented with satellite-linked transmitters and acoustic sound and movement tags (AcousondeTM) over periods of up to 8 days. The records obtained provided continuous information on the whales’ acoustic behavior during foraging and social interactions. Burst-pulses were the most easily recognizable non-feeding vocalization. They tended to occur near the surface and were more common in records that displayed higher rates of clicks from other individuals, i.e., records that presumably would include more social interactions with other narwhals. Over 100 burst pulses detected in eight subjects were analyzed in terms of their overall length and their pattern of successive inter-click intervals (ICIs). While overall length could be somewhat variable, the succession of ICIs was unique for each whale and could therefore have an identity-carrying function, as the signature whistle does in bottlenose dolphins and other odontocetes. The occurrence of these individual-specific burst-pulses in time and space will be examined in relation to other factors provided by the tags, such as the time of day, whale depth, presence of conspecifics, and behavioral state. [Work sponsored in part by the Greenland Institute of Natural Resources.]
What the African naked mole-rat can tell us about mammalian hearing and acoustic communication
Authors: Barone Catherine , Park Thomas , Pyott Sonja
Published: October 2018

African naked mole-rats are eusocial rodents that live underground in narrow burrows. Likely reflecting adaptations to their subterranean environment, naked mole-rats (NMRs) have poor high frequency hearing, relatively high auditory thresholds, and limited ability to localize sound thus providing a unique opportunity to investigate the mechanisms required for high frequency hearing and sound localization. Despite their poor hearing sensitivity, NMRs display a functional coupled auditory-vocal communication system. Prior work revealed they use 17 different vocalizations to communicate within their colonies. Due to their unusual hearing, investigation of NMRs, especially in comparison to other rodent models, provides a unique opportunity to identify features of the auditory system that underlie high frequency hearing, sound localization, and discrimination of vocalizations. Our recent anatomical characterization indicates the NMR cochlea undergoes stunted maturation of peripheral synaptic organization and altered expression of ion channels compared to other mammals. Our more recent function auditory assessments indicate multiple mechanisms that may result in their poor hearing. Overall, these studies provide a framework for comparative insight into the peripheral mechanisms required for high frequency hearing and sound localization.
Airborne and underwater acoustic repertoire of hooded seals (Cystophora cristata): Cornerstone for acoustic monitoring
Authors: Frouin-Mouy Heloise
Published: October 2018

The hooded seal is a migratory species inhabiting the North Atlantic. They whelp and breed during mid- to late March on pack ice near Jan Mayen Island, in the Davis Strait, off the northeastern Newfoundland coast, and in the Gulf of St. Lawrence. After breeding, hooded seals return to the pack ice off eastern Greenland to moult during June and July, and then they disperse broadly for summer and fall before returning to their respective breeding areas. Passive acoustic monitoring conducted over spatial scales consistent with known and potential habitat of the hooded seal could add insight into seasonal, diel, and spatial occurrence patterns of this species. To better characterize its acoustic repertoire (notably underwater calls), airborne and underwater acoustic signals of hooded seals were recorded during their breeding season on the pack ice in the Gulf of St. Lawrence from 12 to 17 March 2018. Hood and septum noises were the predominant sounds heard from males on the ice surface. Hooded seal underwater acoustic repertoire is larger and more diverse than has been previously described. Using the dataset from an extended acoustic monitoring program along Canada’s East Coast, some clues are provided about the seasonal distribution of hooded seals.
Vocalizations of North American river otters (Lontra canadensis) in two human care populations
Authors: Walkley Sarah , Zapetis Maria , Lyn Heidi
Published: October 2018

There is a dearth of information regarding the vocal repertoire of North American river otters (Lontra canadensis). This indicator species is cosmopolitan yet elusive, making recordings methodologically difficult in the wild. Therefore, this exploratory study uses video and audio recordings of two populations of North American river otters in human care to broaden the known vocal repertoire of river otters in various social contexts. The populations consist of a male-female and a male-male pair. This study is the first to examine the vocalizations produced in a male-male pair of river otters. Call types were acoustically distinguished based on their appearance on a spectrogram. Parameters including average duration, frequency (high, low, max, 1st quarter, center, and 3rd quarter), and power (max and average) were measured for each call. Because vocalizations are the focal point of this study, only behaviors co-occurring with vocalizations were included in the chi square analysis that showed a significant relationship between call type and behavior. Squeaks and whines were present during agonistic behaviors while chirps were produced during non-agonistic behaviors including investigating, stationary, and grooming. Results support that behavior likely plays a role in the type of calls produced by river otters in human care.
Passive ocean sensing and soundscape analysis of the Juan de Fuca plate using the Ocean Networks Canada NEPTUNE Array
Authors: Verlinden Christopher M. , Heaney Kevin D. , Schonau Martha C. , Dakin Thomas
Published: October 2018

The Ocean Networks Canada (OCN) deployment of a small set of acoustic recorders (4) in and around the Juan de Fuca plate provides the opportunity to observe the seasonal and long-term trends in the northeast Pacific ocean soundscape. With one receiver near the opening of the Straits of Juan De Fuca, two on the continental slope and one in deep water, we have the opportunity to evaluate the effects of local environment on the ambient sound. Wind waves and surface ships drive the low frequency ambient sound fields in most regions. These long-term recordings provide the opportunity to perform passive acoustic tomography, where the cross-correlation of the acoustic field over long time periods can provide estimates of the channel impulse response between the two hydrophones. This technique has been demonstrated experimentally at shorter ranges. The expected oceanographic observed signal from a “tomography experiment” is estimated using the ECCO4 model and the parabolic equation.
Adding value to big acoustic data from ocean observatories: Metadata, online processing, and a computing sandbox
Authors: Biffard Ben , Morley Michael , Hoeberechts Maia , Rempel Allan , Dakin Thomas , Dewey Richard K. , Jenkyns Reyna
Published: October 2018

Ocean Networks Canada (ONC) operates ocean observatories on all three of Canada's coasts. The instruments produce 300 gigabytes of data per day with over 600 terabytes archived so far. The majority of this data is acoustic, both passive (335 TB) and active (20 TB). This demonstrates the unprecedented capability of cabled observatories to provide unlimited power and data for high bandwidth, continuous data acquisition. Handling this data is a challenge. Metadata, calibration, quality control, and access must be considered. The volume of data is too great for most users to handle. Even if they could store and process it, data transfer to users' computers is a limiting, and perhaps unnecessary step. To address these challenges, ONC has developed a data portal, known as Oceans 2.0, that includes on-demand user-configurable online previewing and processing and a computing “sandbox” where users can upload their own code to process the data. The data portal is now fully accessible by web services. The sandbox is a contained, secure environment with direct access to the data. This paper will present our experience and best practices, including use cases, from acquisition to adding value to the data with these new computing methods.
Long-term monitoring of marine soundscapes: Shipping, biodiversity, and weather at a Pacific seafloor observatory
Authors: Richards Alice , Blondel Philippe
Published: October 2018

Seafloor observatories enable long-term monitoring of marine soundscapes, modulated by weather, biodiversity, and human impacts (e.g., shipping). High-frequency (96-kHz) measurements at the NEPTUNE node of Folger Deep are processed to compare signatures of shipping and natural events over five tidal cycles, spanning several seasons (2009–2011). Independent meteorological data from local surface stations is also used. Sound levels in third-octave frequency bands centred on 63 Hz and 125 Hz are used to monitor shipping, in line with the European Marine Strategy Framework Directive (MSFD). The contribution from the busy shipping lane 40 km away is affected by the complex, shallow bathymetry, whereas local traffic can increase noise levels by up to 30 dB re. 1 μPa, with strong seasonal variation. The relative contributions of the 63 Hz and 125 Hz bands varied contrary to MSFD expectations for deeper areas. Our results match other studies in shallow, coastal environments, showing the importance of depth in interpreting changes. Principal-Component Analyses show that noise from local vessels is the most significant contributor in all seasons, and weather is the second largest, except in summer when biological noise became prevalent. Biodiversity, measured with the broadband Acoustic Complexity Index, showed a strong correlation with weather.
Modeling granular sediments—Experimental results that support the physics included in “Biot-like” models, other possible experiments that could be interesting
Authors: Williams Kevin
Published: October 2018

Under the “all models are wrong but some are useful” philosophy, one may at times allow some abuse of the basic physics if the predictions are accurate. However, few would start with a flawed model when they need not. We start with a thought experiment that indicates a fundamental requirement for capturing the correct dynamics in modeling porous granular media and show that this physics is captured in Biot and Pierce/Carey models as well as models that use them as a starting point. Ocean and laboratory propagation experiments that test the predictions of those models are then described. Since other modeling choices can, given free parameters, predict both granular sound speed and attenuation, we continue by looking at both back and forward scattering results. These results further mandate the need for a model that correctly treats the sediment dynamics. Finally, we present possible additional laboratory experiments that could alter some of the most important parameters inherent in Biot-like models and thus further test the validity of the such models as starting points in granular sediment acoustics. [Work supported by the Office of Naval Research.]
Laboratory and at-sea experiments using a vertical synthetic array technique to measure the sound waves propagating above and below fluid-saturated sediment interfaces
Authors: Simpson Harry J. , Houston Brian H.
Published: October 2018

A series of measurements in the NRL shallow water laboratory were designed and conducted to measure the sound waves propagating in an un-consolidated fluid-saturated porous medium. The novel design used a pair of small receivers, one buried in the bottom and one mounted in the water column to a linear vertical positioner. The buried receiver was carefully inserted into the sandy bottom using a small water-jet, engineered to have no entrained air, to minimally disturb the bottom. The receiver pair were incrementally pulled up through the bottom or water column to map out the sound propagating from a source mounted in the water column. The position of the source was varied to measure above critical angle and below critical angle sound penetration into the bottom. Measurements of carefully smoothed and roughened interfaces were also conducted. This synthetic vertical array technique proved very successful in the laboratory and was transitioned to at-sea measurements in a variety of sandy bottom locations around Panama City, FL. The analysis and modeling of these laboratory and at-sea experiments will be discussed.
An overview of the sediment acoustic models and their experimental validations
Authors: Turgut Altan
Published: October 2018

The Biot theory of acoustic wave propagation in porous media was first adapted to marine sediments by Stoll (1969). To describe the response of a slightly inelastic skeletal frame over a wide frequency range, Stoll introduced the notion of constant complex bulk and shear moduli with small imaginary parts. Stoll’s model predicts f1 frequency-dependence of attenuation at low frequencies and nearly f2 and f1/2 frequency-dependence at frequencies where maximum velocity dispersion occurs. Although the theory well reproduces the velocity and attenuation measurements in marine sediments, the assumption of constant complex moduli slightly violates the causality (Turgut, 1990). The more recent Grain-Shearing (GS) and Viscous Grain-Shearing (VGS) models (Buckingham, 2000 and 2007) are causal and the VGS model also predicts a frequency-dependence of attenuation like that of the Stoll model. With the selection of proper parameter values, both models predict compressional and shear-wave dispersions that are in agreement with those of previous in-situ and laboratory measurements. In addition, the Stoll model predicts the existence of slow compressional waves that have been observed in synthetic porous media (Plona, 1980) but not in natural marine sediments. Several reflection and in-sediment transmission experiments are discussed to facilitate the detection of slow compressional waves in marine sediments. [Work supported by ONR.]
Speed of sound and geo-alpha in clayey silt derived from concurrent inversion of geo and bio-acoustic parameters from transmission loss data and co-located chirp sonar measurements
Authors: Diachok Orest , Turgut Altan
Published: October 2018

Application of the concurrent geo and bio-acoustic inversion method (Diachok and Wales, 2005) to broadband (0.3–5 kHz) transmission loss (TL) measurements, and co-located normal incidence chirp sonar measurements provided measures of geo-acoustic properties of clayey-silt in the Santa Barbara Channel. Inversion calculations assumed that the geological environment may be characterized by the interfacial sound speed, unconsolidated layer thickness, sound speed gradient, g, and geo-alpha, αG; and that the biological environment may be characterized by the layer depth, layer thickness, and bio-alpha (attenuation coefficient within the layer). Co-located cores provided ground truth; echo sounder and trawl measurements provided biological truth. Both the concurrent inversion and the chirp-based methods yielded approximately the same value of g, 6.5/s, in the top 9 m thick layer of clayey-silt. The value of αG, based on TL measurements, was quite low, approximately 0.02 dB/λ, in good agreement with Holland and Dosso’s (2013) only previously reported in-situ estimate of geo-alpha in silty-clay in this frequency-depth range. These results have important implications for estimation of geo parameters from TL measurements in biologically intense environments. Refinements to envisioned follow-on experiments will be discussed. [This research was supported by the Office of Naval Research Ocean Acoustics Program.]
Experimental measurement of tortuosity, viscous, and thermal characteristic lengths of rigid porous material via ultrasonic transmitted waves
Authors: Sadouki Mustapha
Published: October 2018

An inverse method is proposed for measuring tortuosity, viscous, and thermal characteristic lengths of air-saturated porous material with rigid frame via ultrasonic transmitted waves at normal incidence. The equivalent fluid model is considered. The interaction between the fluid saturated the pores and the structure are taken into account in two frequency response factors: the dynamic tortuosity of the medium introduced by Johnson et al. and the dynamic compressibility of the air introduced by Allard. Simplified expression of the transmission coefficient is obtained in frequency domain, and this expression depends on the porosity, tortuosity, viscous, and thermal characteristic lengths. The inverse problem is solved numerically in time domain by minimizing between simulated and experimental transmitted waves. The inverted parameters are in good agreement with those obtained using conventional methods. Simulated signals are reconstructed using the optimized values found and compared with the experimental signals. Tests are performed using three different plastic foam samples having low flow resistivity. The proposed technique has the advantage of being simple, fast, and not expensive.
Fractional viscoelastic modelling of wave propagation in fluid-saturated marine sediments
Authors: Pandey Vikash
Published: October 2018

It is shown that Buckingham's grain-shearing (GS) model [JASA (2000)] as well as its improved viscous-GS (VGS) model [JASA (2007)] can be expressed using the mathematical framework of fractional calculus. The fractional version of the standard fluid model is adopted to independently arrive at the wave equations and dispersion relations derived by Buckingham. The fractional-order wave equations obtained for the compressional waves and shear waves are relatively easier to analyse due to their closed-form representation in the fractional framework. It is also shown that the fractional calculus approach may help in bridging the disparate fields of non-Newtonian rheology and sediment acoustics, which may have actually developed independently of each other. Further, the experimental data relating wave dispersion and attenuation in marine sediments is found to match with the predictions from the fractional framework. The overall goal is to show that fractional calculus is not just a mathematical framework that can only be applied to curve-fit the observational data for complex media. In fact, it has an inherent connection to real physical processes that needs to be explored more.
Photo-thermal transient stress observed by sub-nanosecond pump-probe technique with the surface plasmon resonance
Authors: Hayashi Hiromichi , Ichihashi Hayato , Ueno Shoya , Matsukawa Mami
Published: October 2018

Photoacoustic microscopy (PAM) has attracted attention as a non-invasive observation tool for biomedical studies. However, the spatial resolution is unsuitable for precise imaging of a single cell due to the characteristics of the ultrasonic transducer. In recent years, the surface plasmon resonance (SPR) sensor has been reported as a technique with a high-spatial resolution and ultra-flat frequency response. SPR is expected to be the future optical detector for photoacoustic imaging. As a first trial, using a Kretschmann-configuration SPR sensor (Ag (53 nm)/BK7 glass prism), we observed the photo-thermal transient stress and the consequent change in refractive index using the sub-nanosecond pump-probe technique. The signal intensity of the thermo-elastic stress produced by the pump beam excitation was measured by changing the incident angle of the probe beam. The spot diameter of the probe beam was 5 μm. The highest intensity signal was observed at the SPR angle (46.5 deg.) of the plasmon resonance. Results suggest that the SPR sensor effectively enables the non-contact and non-destructive measurements of the thermo-elastic stress. Further researches will implement the SPR sensor for tissue characterization by attaching biological samples on the Ag surface.
A biomechanical model for infant speech and aerodigestive movements
Authors: Mayer Connor , Stavness Ian , Gick Bryan
Published: October 2018

A central question in speech acquisition is how infants are able to learn speech movements rapidly and with limited input. A relatively untested but appealing hypothesis is that some core speech movements may build on preexisting aerodigestive movements like swallowing and suckling (e.g., MacNeilage, 2008, The Origin of Speech; Studdert-Kennedy & Goldstein, 2003, Launching Language). We will present a model of an infant tongue and palate using a 3D biomechanical simulation platform (www.artisynth.org; e.g., Stavness et al., 2012, J. Biomech. 45(16): 355–394; Gick et al., 2014, Compu. Meth. in Biomech. & Biomed. Eng.: Imag. & Vis. 2(4): 217–222). This model, generated from CT and MRI imaging data, will be capable of simulating both swallowing and simple speech movements. The results of simulations using this model will provide useful insight into infant motor control, and will help to supplement neurological, clinical, and kinematic evidence relating speech and aerodigestive movements. [Funding from NSERC.]
Automated episode selection of child continuous speech via blind source extraction
Authors: Speights Marisha , Gilbert Keith D. , MacAuslan Joel , Goldhor Richard
Published: October 2018

Commonly, in both research and clinical conditions in which speech recordings are collected from children, the non-targeted adult speech and the targeted child speech are simultaneously recorded during conversational turn-taking tasks, and the utterances of all talkers are audible on every channel of the recording. As a result, the intended analysis of the targeted speaker becomes encumbered by the requirement for a human analyst to identify and mark the episodes in the recording where the targeted speaker is the only active sound source. Blind source extraction (BSE) techniques are utilized here to automatically deliver the isolated child’s speech, even when the child’s and adult’s speech overlap, or when extraneous interfering noise is present. To test the performance of the BSE methods for automated episode selection in child continuous speech, ten typically developing children were each recorded speaking thirty-three sentences in the turn-taking scenario with four microphones placed in the environment. Correlation between the numbers of human-marked episodes identifying the target speakers to the machine-selected episodes was examined. Results of the Pearson correlation indicate there is a significant positive association between hand counts and BSE machine counts (r = 0.85, p <0.01).
Perception of talker height and sex from children’s voices
Authors: Assmann Peter F. , Kapolowicz Michelle R. , Barreda Santiago
Published: October 2018

Several recent studies have investigated the ability of listeners to judge the height of adult talkers from their speech. Here, we examine the perception of talker height from a sample of /hVd/ syllables spoken by children ranging in age from 5 through 18 years, with 3 talkers of each sex at each age level. Twenty college students judged the height and sex of the talker for each trial. Perceptual estimates of height were moderately correlated with actual height (for males, r = 0.78; for females, r = 0.67). Consistent with our recent findings concerning the perception of talker age [Barreda & Assmann, JASA-EL 143(5), EL361, 2018], listeners' judgments of talker height appear to incorporate assumptions about talker sex and the relationships between speech acoustics and veridical height for male and female talkers of different heights. For example, when older girls were misidentified as boys, their height was likely to be underestimated. This behavior results in predictable error patterns in height judgments from speech: in situations where talker sex is misidentified, listeners apply the “wrong” acoustic model to estimate talker height, leading to correlated error patterns between apparent height and sex.
Perceptual restoration of interrupted speech in typically-developing school-age children: Effect of interruption rate
Authors: Magimairaj Beula M. , Nagaraj Naveen K.
Published: October 2018

Auditory closure, the ability to fill-in missing information involves bottom-up and top-down influences. There is a lack of systematic studies on children’s interrupted speech perception (ISP). We measured 8- to 11-year-old typically developing children’s restoration of sentences using the ISP paradigm. We used two interruption rates with noise-filled and unfilled interruptions, respectively. Sentences from the Bamford Kowal Bench Speech-in-Noise Test were gated with 50% duty cycle square wave at 2.5 and 5 Hz. For the noise-filled condition, silent intervals were filled with speech noise. Preliminary analysis on 33 children has been completed and 40 more children are scheduled complete participation. Accuracy of keyword recognition was subjected to 2 (interruption rate: 2.5 vs. 5 Hz) X 2 (noise-filled vs unfilled) repeated measures ANOVA. Overall, main effect of interruption rate, F(1, 32) = 500, p <0.0001 and filler noise was significant, F(1, 32) = 289, p < .00001. Recognition scores for noise-filled conditions were better than unfilled for both 2.5 Hz (mean difference = 27.2) and 5 Hz (mean difference = 5.03) conditions. Larger perceptual restoration at 2.5 Hz compared to 5 Hz may indicate greater reliance on lexical knowledge at 2.5 Hz to restore speech than on phonemic restoration.
Velopharyngeal control for speech in children with cochlear implants: Nasalance data in vowel and consonant segments
Authors: Koenig Laura L. , Okalidou Areti , Psillas George
Published: October 2018

Children with hearing loss before the development of their phonological system display various kinds of atypical speech production characteristics. Cochlear implants (CIs) can lead to improved speech production, although children may vary considerably in their outcomes. Past work suggests that one effect of hearing impairment is poor control over the velopharyngeal system, but little direct data exist to show how CIs improve velopharyngeal function for speech. This work presents nasometer data for Greek-speaking children with CIs, ages 4–16 years, along with age- and gender-matched typically-hearing children. Children produced bisyllabic words varying in stress position and in the type of initial stop consonant: Nasal, voiceless unaspirated, and voiced (which, in Greek, may be produced as prenasalized). The nasal and oral microphone signals from the nasometer were labelled in Praat to demarcate consonantal and vocalic regions. Preliminary analyses on the whole words suggested that children with CIs are comparable to hearing controls for words beginning with nasal consonants, but differed for words with oral consonants. This presentation will present durations and average nasalance over segmental (consonantal and vocalic) regions, permitting more fine-grained assessment of velopharyngeal control.
Children’s ratings of vocal emotion intensity depend on the emotion spoken and speaker familiarity but not acoustic parameters
Authors: Stoop Tawni B. , Moriarty Peter , Vigeant Michelle , Gilmore Rick , Liu Pan , Cole Pamela
Published: October 2018

Scherer (1986) documented the acoustic parameters associated with adults’ perceptions of discrete vocal emotions. We investigated physical and psychological factors that influence children’s ratings of discrete vocal emotions using stimuli that approximated naturally occurring speech, including familiarity with the speaker. Specifically, we presented 52 7- and 8-year-olds with one side of a brief phone conversation spoken in happy, angry, sad, and non-emotional prosodies by both the child’s mother and another child’s mother, unfamiliar to the target child. As a group, the familiar and unfamiliar mothers’ prosodies did not differ in fundamental frequency (F0), F0 standard deviation, or speech rate—acoustic parameters that are most identified with angry, happy, and sad prosodies. Children accurately recognized the emotion spoken: They rated angry stimuli as more angry than happy or sad. Regression analyses indicated that speaker familiarity predicted children’s intensity ratings even after the target acoustic parameters were taken into account, but this effect was moderated by speaker emotion, such that children rated their mothers as more intensely angry than unfamiliar mothers. The findings suggest that their mother’s angry voice holds psychological significance for children that is not explained by variations in its most salient acoustical properties.
Acoustic analysis of the speech of patients with oral cancer: A methodological investigation comparing speech stimuli derived from different clinical outcome measures
Authors: Dzioba Agnieszka , Aalto Daniel , Seikaly Hadi , Rieger Jana
Published: October 2018

Background: Oral cavity cancer and its treatment reduce the quality of speech. Clinicians often utilize a variety of outcomes measures to assess speech function of patients with oral cavity cancer reducing the comparability of formant results due to differences in linguistics and phonetic contexts. Objective: To evaluate the degree of agreement in vowel space size in a F1-F2 plane, when comparing speech stimuli selected from a controlled environment (i.e., /hVd/ context) to speech stimuli segmented from two clinically available speech outcome measures in patients treated for cancer of the oral tongue. Methods: Voice recordings of nine patients treated with primary surgery for cancer of the oral cavity who attended functional assessment appointments (pre-operatively, and at 1-, 6-, and 12-months post-operatively) were analyzed. Agreement between vowel space size obtained from /hVd/ phrases and other speech assessments were compared using linear correlations and t-tests. Results: Vowel space size derived from /hVd/ phrases correlates strongly with corresponding estimates from other speech tasks (r = 0.72 to 0.82, p <0.0001). The other tasks had significantly reduced vowel space sizes compared to /hVd/ (t = 4.7 to 5, p<0.0001). Conclusion: Vowel space size estimates based on different speech tasks are mutually comparable and may offer insight to oral cancer speech production acoustics.
Tongue position during speech as a function of palatal anatomy: Controls and glossectomy patients
Authors: Stone Maureen , Tigani Elise , Tigani Elise , Lee Junghoon , Woo Jonghye , Prince Jerry L.
Published: October 2018

This study examined the effect of palatal anatomy on tongue position during the complex speech movement seen in the motion from /ʃ/ to /l/ in “shell.” The study was interested in whether subjects with flatter/narrower palates would use more tongue anteriority than those with higher/wider palates. Anteriority is the percent of the tongue anterior to the first molar. Low palate speakers may use more anteriority due to less space in the palatal vault. The speech task “a shell” requires complicated deformation between the /ʃ/, which elevates the sides of the tongue, and the /l/, which lowers the sides, elevates the tongue tip, and retracts the root. In the past, palate effects have been shown to explain idiosyncratic subject differences. Palate height explained the use of apical vs laminal /s/. Palate width affected the anteriority of tongue position in cancer patients after glossectomy surgery. Therefore, this study examined 16 controls and 8 glossectomy patients. Initial measurements show more anteriority for patients than controls. In addition, patients with a large overbite (vertical overlap between upper and lower incisor) had more anteriority due to a smaller front cavity.
Diphthong productions in speakers with Parkinson’s disease across speaking modes
Authors: Kim Yunjung , Thompson Austin R.
Published: October 2018

Several vowel acoustics parameters (e.g., second formant frequency (F2) slope, vowel space area) are known to significantly contribute to speech intelligibility in dysarthria (Kim, Kent, Weismer, 2011; Lansford & Liss, 2014). Particularly, F2 slope has been identified as an important predictor of speech intelligibility regardless of underlying neuropathologies of dysarthria (Kim, Weismer, Kent & Duffy, 2009). The current study focuses on intra-speaker modifications of F2 slope in speakers with Parkinson’s disease (PD) voluntarily elicited across three speaking modes, less clear, conversational, and more clear speech, in recognition that prior work has mostly focused on inter-speaker comparisons. Varying speech clarity was our interest, given its wide use as an efficient behavioral therapeutic approach in clinic. Twenty speakers (10 PD, 10 neurologically healthy) were asked to read diphthongs embedded in real words. Diphthongs were chosen because they require a significant change in configuration of vocal tract and, therefore, are sensitive to the presence/severity of dysarthria. In the presentation, distributions of F2 slope 1) between PD and healthy speakers, and 2) across speaking modes within each speaker will be discussed. In addition, articulatory data will be presented for part of the speakers from whom kinematic data were obtained using the electromagnetic articulography (EMA) system.
Enhancing speech adaptation to a palatal perturbation using ultrasound visual biofeedback
Authors: Barbier Guillaume , Shiller Douglas
Published: October 2018

Prior clinical studies suggest that visual biofeedback of the tongue (e.g., ultrasound) may enhance the treatment of speech disorders, but outcomes have been mixed, likely due to variability in both the clinical profiles of participants and the way in which treatments have been carried out. Understanding the true potential of this clinical tool requires a clearer sense of how visual biofeedback interacts with speech motor control. Here, we present a novel experimental approach that mimics the conditions of clinical treatment for speech disorders while maintaining a high level of consistency and control over the speech-learning task. The procedure involves altering the vocal tract of typically developing talkers using a palatal prosthesis to perturb /s/-production in combination with the controlled application of ultrasound biofeedback. As participants practice and improve their speech, changes in articulatory movements are examined using acoustic and kinematic measures. The present study compared a control group (n = 10) receiving only auditory feedback during speech practice with a group receiving visual biofeedback (n = 10). Results indicate an effect of biofeedback, in particular in the retention of learned motor patterns, indicating that talkers integrate real-time visual feedback of tongue movement into the sensorimotor processes driving speech adaptation.
The effect of noise on the intelligibility of electrolaryngeal speech
Authors: McNicholl Kimberly , Cox Steven R. , Chill Alexandra
Published: October 2018

The electrolarynx (EL) is a hand-held device used for voice and speech production following surgical removal of the larynx. Many individuals who have their larynx removed begin using an EL in the immediate, postsurgical period. Unfortunately, EL speech is known to be poorly understood in quiet listening conditions when compared to laryngeal and alaryngeal speech methods. However, there is a dearth of research studying the effects of background noise and its impact on the intelligibility of EL speech. The purpose of this study, then, was to investigate how well naïve listeners identify EL speech in quiet and noise conditions. Ten EL speakers were recorded while reading 10 sentences containing five keywords per sentence. Twenty listeners were asked to orthographically transcribe 50 sentences each while listening to the EL speakers’ recordings. Preliminary data indicate that listeners identified 76% of keywords (Mdn = 78%; SD = 5%, range= 69–80%) in quiet compared to 60% of keywords (Mdn = 63%; SD = 10%; range = 44–69%) in noise. Implications and future directions will be discussed.
Visual-aerotactile perception and congenital hearing loss
Authors: Chang Charlene , Keough Megan , Schellenberg Murray , Gick Bryan
Published: October 2018

Previous research on multimodal speech perception with hearing-impaired individuals focused on audiovisual integration with mixed results. Cochlear-implant users integrate audiovisual cues better than perceivers with normal hearing when perceiving congruent [Rouger et al. 2007, PNAS, 104(17), 7295–7300] but not incongruent cross-modal cues [Rouger et al. 2008, Brain Research 1188, 87–99), leading to the suggestion that early auditory exposure is required for typical speech integration processes to develop (Schorr 2005, PNAS, 102(51), 18748–18750). If a deficit of one modality does indeed lead to a deficit in multimodal processing, then hard of hearing perceivers should show different patterns of integration in other modality pairings. The current study builds on research showing that gentle puffs of air on the skin can push individuals with normal hearing to perceive silent bilabial articulations as aspirated. We report on a visual-aerotactile perception task comparing individuals with congenital hearing loss to those with normal hearing. Results indicate that aerotactile information facilitated identification of /pa/ for all participants (p < 0.001) and we found no significant difference between the two groups (normal hearing and congenital hearing loss). This suggests that typical multi-modal speech perception does not require access to all modalities from birth. [Funded by NIH.]