bluuebunny/crossref_metadata_2025 huggingface dataset:
Fabrication and measurement of a hybrid resonant gradient index metasurface at 40kHz
Authors: Gerard Nikhil J. , Cui Huachen , Shen Chen , Cummer Steven , Zheng Xiaoyu , Jing Yun
Published: April 2019

Over the past decade, gradient index metasurfaces(GIMs) have been voraciously studied for the numerous wave control capabilities that they facilitate. In this regard, a hybrid structure consisting of shunted Helmholtz resonators and a straight channel is often chosen as building blocks of the metasurface. Prior research, however, has primarily focused on GIMs that operate in the audible frequency range, due to the difficulties in fabricating such intricate structures at the millimeter and sub-millimeter scales, for ultrasonic applications. In this paper, we design, fabricate and experimentally realize a gradient index metasurface for airborne ultrasound at 40kHz. The fabrication of such a GIM is made possible by projection micro-stereolithography, an emerging additive manufacturing technique capable of micro-scale, high aspect-ratio features over a wide area. Simulations were first conducted to verify the metasurface design. Experiments were subsequently performed to corroborate the simulations and theory. The challenges faced by the thermoviscous effects, their usefulness in certain applications and optimal designs for minimal dissipation are discussed.
Transmission enhancement through arbitrary layers with bianisotropic metasurfaces
Authors: Li Junfei , Shen Chen , Cummer Steven
Published: April 2019

Acoustic metasurfaces are thin, engineered structures that can control the local reflection and transmission coefficients of acoustic waves. Here, we describe our recent framework on general impedance matching with bianisotropic metasurfaces, in which elements are designed to control the local asymmetric impedance matrix. Compared with conventional quarter wavelength impedance matching layers, our proposed metasurface, with arbitrary thickness, can maximize wave transmission through an arbitrary layer with controlled phase. As a showcase, we demonstrate the design of a metasurface that helps ultrasound in water to penetrate a steel plate with almost 100% power efficiency and controlled transmission phase, which is beyond what is possible with conventional impedance matching layers. Our approach also applies to electromagnetic scenarios to help waves transmitting through walls or even metal plates.
The development of emotional speech prosody perception in 3- to 14-month infants: a preferential listening study
Authors: Kao Chieh , Zhang Yang
Published: April 2019

Developmental studies have shown strong evidence that socially enriched speech signal (including prosodic modifications) attracts infants’ attention and facilitates language development. While emotion understanding is evident at 9 months of age (Otte et al., 2015), the developmental trajectory of the emotional speech prosody perception is still unclear. The present study adopted a widely used preferential looking paradigm to measure 3- to 14-month-old infants’ listening preference to English words spoken in neutral, happy, angry, and sad tones. Analysis using a linear mixed model showed that infants’ preference of emotional prosody changed as a function of age. On average, the three-month olds listened longer to all emotional prosodies over the neutral one whereas older infants showed significantly diminished interests in the sad prosody, followed by the happy and angry voices. Around 12 months, infants appeared to listen to emotional prosodies equally with the exception of reduced interest in the angry prosody. These preferential listening measures were not correlated with the varying durations or fundamental frequencies of the spoken words for the different emotional categories, indicating that the development of emotional speech prosody is not purely driven by the acoustical properties but rather involves higher-order social cognition.
The effects of parent coaching on language outcomes at 18 and 24 months: A randomized controlled trial
Authors: Ferjan Ramirez Naja , Lytle Sarah , Cai Ruofan , Kuhl Patricia K.
Published: April 2019

The prevalence of parentese in speech directed to 11- and 14-month-old infants predicts infants’ concurrent babbling as well as their future language skills at 24 months, suggesting that this speaking style may enhance learning. We recently showed that when parents are “coached” about the importance of language input to infants, and parentese, they increase the proportion of parentese and child-directed speech. This has an immediate and positive effect on child language outcomes at 14 months. In the present study, we asked whether the effects of coaching parents extend to longer-term language outcomes. Families of typically developing 6-month-old infants were assigned to Intervention (parent coaching) and Control (no coaching) groups. Parent coaching took place when infants were 6- 10-, 14- and 18-months of age, and included quantitative and qualitative linguistic feedback derived from each family’s first-person LENA recordings at home. Language outcomes were measured at 18- and 24-months of age. Parent coaching significantly enhanced the percentage of child-directed speech and parentese in parental input between 6 and 18 months in coached vs. uncoached parents. Children of parents who received coaching showed enhanced language outcomes at 18 and 24 months.
The effects of parental interaction on French-English bilingual infants’ vocalization and turn-taking rates
Authors: Xu Katherine , Orena Adrial J. , Ruan Yufang , Polka Linda
Published: April 2019

Prior studies suggest that parent-infant interactions play an important role on infant volubility, which is an important indication of language development. However, little is known about how speaker and language contexts affect infant volubility in bilingual infants. In the current study, we examined how the speaker context (Mother versus Father) and the language context (French versus English) might influence bilingual infants’ rate of vocalization and turn-taking. We analyzed naturalistic daylong recordings from English-French bilingual parent/infant dyads (n = 21). Preliminary analysis showed that mothers elicited more turn-taking in their 10-month-old infants than fathers did, but they did not elicit more vocalizations. Importantly, there was no effect of language on infant vocalization or turn-taking. We will alsoreport analyses that examine whether the dominant language in the bilingual child’s input has an effect on infant volubility that is independent of talker effects. These novel findings will inform our understanding of how parent-infant interactions shape the language development of infants being raised in bilingual families.
Infant-directed speech enhances recognizability of individual mothers’ voices
Authors: Kathiresan Thayabaran , Dilley Laura , Townsend Simon , Shi Rushen , Daum Moritz , Arjmandi Meisam K. , Dellwo Volker
Published: April 2019

Adult speakers commonly alter their voices when talking to infants, giving rise to an infant-directed speech (IDS) style. Here we tested the effects of infant-directed speech on the recognizability of a speaker’s voice. 10 Swiss-German mothers were recorded talking to their infants IDS and talking to an adult experimenter (in adult-directed speech, ADS). We studied the indexical properties using Mel-frequency cepstral coefficients (MFCCs). By using an unsupervised K-means clustering algorithm, the segmental 13-dimensional MFCCs were clustered and reduced to two dimensions using Principal Component Analysis. Results showed that the relative area of IDS occupied in the 13-dimensional space was significantly larger compared to the area occupied by ADS. A supervised language-independent Gaussian Mixture Model revealed that this expansion benefitted the recognizability of mothers’ voices. This means that the higher indexical variability in IDS fosters recognition of individual mothers. Results are consistent with the view that IDS may have evolved in part as a strategy to promote indexical signaling by a mother to her offspring, thereby promoting mother-infant attachment and fostering offspring survival.
Measurements of two-dimensional spatial coherence of normal-incidence seafloor scattering
Authors: Brown Daniel C. , Brownstead Cale F. , Lyons Anthony P. , Gabrielson Thomas B.
Published: April 2019

The two-dimensional spatial coherence of the field backscattered from a complex lakebed has been characterized in a series of measurements made in Seneca Lake, New York. In the test region, the lakebed consists of a series of sediment layers created by a sequence of distinct depositional processes. The spatial coherence depends on the structure of the underlying sediment sequences. Significant ping-to-ping variability in the spatial coherence surface is observed for each sediment sequence. This variability is quantified by a two-dimensional spatial coherence metric that measures the coherence lengths and asymmetric coherence surface orientation. Sediment sequences with isotropic scattering strength exhibit random ping-to-ping variability in coherence length and coherence surface orientation. Sequences with spatially anisotropic scattering strength show intervals of non-random ping-to-ping variability in the coherence length and coherence surface orientation.
Simulation and testing results for a sub-bottom imaging sonar
Authors: Brown Daniel C. , Johnson Shawn , Gerg Isaac , Brownstead Cale F.
Published: April 2019

The problem of detecting buried unexploded ordnance is addressed with a sensor deployed from a shallow-draft surface vessel. The sonar system produces three-dimensional synthetic aperture sonar imagery of both surficial and buried ordnance across a range of environments. The sensor’s hardware design is based in part upon data created using a hybrid modeling approach that combined results from separate environmental scattering and target scattering models. This hybrid model produces synthetic sensor data where the sensor/environment/target space may be modified to explore the expected operating conditions. Based on these modeling results, a sonar system has been integrated to a test platform, and experiments have been conducted at a trial site in the Foster Joseph Sayers Reservoir near Howard, PA. Modeling and experimental results will be presented and discussed.
Modeling variability in spatial coherence measurements for seafloor scattering
Authors: Blanford Thomas E. , Brown Daniel C. , Meyer Richard J.
Published: April 2019

Correlation sonar systems, such as correlation velocity logs and synthetic aperture sonar micronavigation, can estimate platform motion using measurements of the spatial coherence of seafloor scattering. During the course of operation, the spatial coherence measurements made by these systems will fluctuate about their average values. A variety of factors, including noise sources, changing environmental properties, and statistical estimation error can all contribute to the variability in these measurements. This presentation will introduce models that can be used to predict the variability in measurements of spatial coherence. These models will be compared with field measurements of spatial coherence collected at normal incidence to the bottom of Seneca Lake. Finally, the application of these models will be discussed as they relate to the design of arrays and signal processing algorithms for correlation sonar systems. (The authors want to acknowledge the financial support for this work by Lockheed Martin Rotary and Mission Systems.)
Biomimetic sonar echo parameters form cognitive maps
Authors: Kuc Roman B.
Published: April 2019

A biomimetic audible sonar probes 2.5D targets and processes binaural echoes to extract values of eight parameters to generate two-dimensional cognitive maps. Targets are configured using posts connected by tangential planes. Being tuned to recognize posts and planes, the sonar produces a cognitive map that is composed of these two components. A platform with translational and rotational degrees of freedom employs right-ear dominance to implement a landmark-centric scanning trajectory whose step size adaptively changes with echo information. The sonar tracks the target by maintaining a constant first echo arrival time and equalizes binaural echo times to form singular echoes. When observed, singular echoes identify landmarks defined by post radii and locations. The mapping process employs five states from detection to termination that passes through the singular echo state. Separate states detect post pairs that exhibit echo interference and planes that exhibit echo amplitude differences. The scanning process terminates when the current landmark parameters match those of the first landmark. Two targets configured with three posts and an added plane illustrate the procedure.
Linear and non-linear features of teleost acoustic communication and implications in software defined communication protocols
Authors: Matthews Cameron A.
Published: April 2019

Many teleost species communicate via acoustic paths. Many times these paths are chosen through evolution in a way that scientists find contrary to practical physics associated with the ocean environments they are born from. This leads to a practical question of why animals would not naturally become the best basis for acoustic communication, particularly in the emerging market of software defined radios and their application in undersea acoustics. We propose a grouping of three distinct acoustic communication “styles” in terms of linearity—periodic linear, periodic non-linear, and aperiodic non-linear—and what the implications are for a dynamic and relatively wide band software defined communication system are.
Investigating Atlantic bottlenose dolphin mismatch negativity response to pure tone stimuli
Authors: Romanchek Brittany A. , Scheifele Peter M.
Published: April 2019

Marine mammals rely heavily on acoustic cues to survive but are susceptible to hearing impairment due to anthropogenic noise. The quality of life and well-being of marine mammals under professional care is based on enrichment through training and communication conspecifics and zoo staff. Mismatch Negativity (MMN) is an electrophysiological exam that records synchronized firing of neurons from the auditory cortex and frontal lobe, allowing for assessment of echoic memory and sound differentiation capability. The objective of this study is to conduct MMN exams, with acoustic stimuli, on the Atlantic Bottlenose Dolphin (Tursiops truncatus Montagu) to study echoic memory and develop auditory cognition assessments for marine mammals in captivity. Three male Atlantic Bottlenose dolphins were tested in water at the Indianapolis Zoo. The oddball paradigm in this study included a frequency difference between two pure-tone stimuli (standard 2000 Hz, deviant 500 Hz). The results suggest that a similar MMN waveform morphology and latency (between 100 and 300 ms) are seen in dolphins when compared to humans. Average P1, N1, P2, and MMN values were determined for each dolphin. Developing MMN tests for animals under professional care will allow for application to marine mammals in natural habitats, which are exposed to high levels of anthropogenic noise.
What is a scream? Acoustic characteristics of a human call type
Authors: Schwartz Jay W. , Engelberg Jonathan W. , Gouzoules Harold
Published: April 2019

Recent research suggests that human screams comprise an innate call type, yet the defining acoustic structure of screams has not been determined. In this study, participants listened to 75 human vocal sounds, representing both a broad acoustical range and array of emotional contexts, and were asked to classify each as either a scream or a non-scream. Participants showed substantial agreement (Fleiss’ kappa test, κ = 0.62) on which sounds were considered screams. To characterize the acoustic structure of screams, we measured the stimuli on 28 acoustic parameters. PCA and GLMM analyses indicated that the classification as a scream was positively correlated with 3 acoustic factors: one corresponding to high pitch and roughness, another corresponding to a wide fundamental frequency range and narrow bandwidth, and a third negatively correlated with roughness. Thus, the role of roughness in identifying screams appears to depend in part on pitch. Twenty-six stimuli were agreed upon by > 90% of participants to be screams, but others evoked mixed responses, suggesting that while screams might represent an innate call type, their acoustic structure is not narrowly fixed, perhaps reflecting the range of emotions and contexts in which humans employ them. The evolutionary significance of scream acoustics is discussed.
Synergy of light and sound for deep-tissue optical imaging and focusing
Authors: Lai Puxiang
Published: April 2019

Light and sound are the two most dominant mechanisms with which we naturally perceive this world. Both have their significant impacts yet with inherent limitations. For example, sound is insensitive to soft tissue functional changes, and light is strongly scattered in tissue, resulting in a trade-off between penetration depth and resolution. Here, we present our most recent research efforts of exploiting the synergy of light and sound to overcome this limitation. Specifically, photoacoustics converts diffusive photon into non-scattering ultrasonic waves, enabling a high-contrast sensing of optical absorption with ultrasonic resolution in deep tissue, overcoming the optical diffusion limit from the signal detection perspective. The generation of photoacoustic signals, however, is still throttled by the attenuation of photon flux due to the strong diffusion effect of light in tissue. Therefore, wavefront shaping is introduced, so that multiply scattered light could be manipulated so as to retain optical focusing or sufficient photon flux even at depths in tissue. We will present the recent development of photoacoustic imaging and optical wavefront shaping in our lab. Potential applications, existing challenges, and further improvement are also discussed.
Spectroscopic photoacoustic imaging for cardiovascular interventions
Authors: Iskander-Rizk Sophinese , Kruizinga Pieter , Wu Min , van der Steen Antonius F. W. , Van Soest Gijs
Published: April 2019

Alongside ultrasound imaging, photoacoustic imaging (PA) augments the imaging system with tissue composition information. Indeed, PA primarily maps tissue optical absorption and thus can reveal tissue composition. Localizing and identifying specific biomolecules can be very useful for both diagnostic imaging and evaluation of the treatment effect in various applications. PA imaging can for instance discern lipid-rich atherosclerotic plaques from fibrotic ones. It can also distinguish highly vascularized or highly oxygenated tissue from hypoxic areas in tumors. However, multiple parameters affect the PA signal received, rendering a direct mapping from signal received to absorption challenging. For instance, at selected wavelengths, multiple chromophores may contribute to the signal observed. In order to separate the different chromophores, judicious spectral tuning of imaging wavelengths can help. We call this technique spectroscopic photoacoustic imaging (sPA). Based on sPA imaging, we were capable to super-localize sources down to 1/20th of the imaging system point spread function (PSF). sPA can also improve the imaging specificity and sensitivity of targeted tissue features. In this talk, we showcase the many benefits of sPA imaging for image enhancement. We also discuss challenges and feasibility to integrate in surgical tools for minimally invasive interventions. In particular, we focus on how sPA studies can take the specific problem of visualization of RF ablation for atrial fibrillation from bench to bedside.
Towards photoacoustic sensing and mapping of neuroelectrical and hemodynamic activity
Authors: Chitnis Parag V.
Published: April 2019

Understanding the neurological function and disorders is an enduring challenge, particularly because the brain activity involves a diverse set of chemical, ionic, and electrical interactions spanning a wide range of spatial scales from microns to several centimeters. Recording these time-varying dynamics in intact, mammalian brain provides an insight into how signaling is processed in neural networks and how these signals modulate physiological function. Optical-fluorescence techniques have emerged as tools of choice for the imaging neuronal activity. Despite significant advances in fluorescent voltage and calcium reporters, these methods are limited to penetration depths of less than 1 mm. One viable alternative to overcome the depth limitation is photoacoustic sensing, which relies on absorption of light and subsequent thermoelastic generation of ultrasound. Photoacoustic methods provide spectroscopic specificity to endogenous and exogenous chromophores, but the molecular information is relayed to the sensor acoustically, which is not as susceptible to scattering in tissue as light. We will present on ongoing efforts to develop (1) PA-based voltage reporters, (2) photoacoustic imaging of the voltage and hemodynamic activity at micro- and meso-scales, and (3) a deep learning framework for achieving super-resolution (exceeding the diffraction limit of ultrasound) photoacoustic tomography of the brain. [Partially supported by NIH-1R21EY023012.]
Multi-pitch spike representation using a Finite-Difference Time Domain (FDTD) cochlear model
Authors: Bader Rolf
Published: April 2019

The spike representation of multi-pitch sounds leaving the cochlear is discussed using a Finite-Difference Time Domain (FDTD) physical model of the cochlear with musical sounds as input. Previously, the model has lead to a new pitch theory, where it was found that the interspike intervals (ISI) of the fundamental periodicity of a single-pitch sound are present at multiple Bark bands in the cochlear. This is due to drop-outs of spikes in Bark bands of higher harmonics. Pitch is therefore represented as the most prominent periodicity within the auditory nerve. In the multi-pitch case, the model shows several cases of such multi-Bark periodicities. With multi-pitch sounds having a residual pitch, the strongest of these multi-Bark cases is that of the residual periodicity. With several pitches perceptually clearly distinguishable one from another, each pitch periodicity appears as a multi-Bark periodicity. Still with sounds where the single pitches are not so clear and separating them needs musical training and intense and multiple listening of the sound, the multi-Bark cases are blurred. Therefore, the model represents the perception of multi-pitch sounds during immediate perception and identification of multiple pitches needing musical training is no longer present at this low-level sound representation at the cochlear output, as expected.
Perceptual fusion of musical notes suggests universal representations of dissonance despite culture-dependent aesthetic associations
Authors: McPherson Malinda J. , Dolan Sophia E. , Ossandon Tomas , Valdes Joaquin , Undurraga Eduardo A. , Jacoby Nori , Godoy Ricardo , McDermott Josh
Published: April 2019

Music varies enormously across cultures, but some traits are widespread. Cross-cultural consistency in music could be driven by universal perceptual mechanisms adapted to natural sounds, but supporting evidence has been circumstantial due to the dearth of cross-cultural research. Here, we explore whether such perceptual mechanisms impose universal similarity relations on musical structure, potentially dissociating from culture-specific aesthetic judgments about music. We measured one possible signature of these similarity relations—the extent to which concurrent notes are perceived as a single sound—in members of a small-scale Amazonian society and Western listeners. We also measured aesthetic responses to the same stimuli. Unlike Westerners, Amazonian listeners were aesthetically indifferent to whether note combinations were canonically consonant (with aggregate frequency spectra resembling the harmonic series). However, Amazonians were nonetheless more likely to hear consonant combinations as a single sound, with fusion judgments that qualitatively resembled those of Western listeners. Thus, even in a culture with little exposure to Western harmony, reliance on harmonic frequency relations for sound segregation evidently induces consistent perceptual structure in note combinations. The results suggest that perceptual mechanisms for representing music can be shared across cultures, even though the perceptual equivalences that result give rise to culture-specific aesthetic associations.
Extraordinary manipulations of particles by acoustic radiation forces and torques
Authors: Zhang Likun
Published: April 2019

Particle manipulations using radiation forces and torques produced by acoustic waves have been found valuable applications in biomedical and material engineering. Recent work suggests extraordinary manipulations of particles associated with direction reversals of forces and torques by some specific sound beams. When considering the three-dimensional acoustic radiation force, the momentum view enlightens into the superposition and coupling of manipulations by multiple beams and the force dependence on scattering functions [L. Zhang, JASA 144 (1), 443–447 (2018)]. It is efficient to apply the superposition to consider forces and torques on particles moved away from the equilibrium trapping position [L. Zhang, JASA 143(5), 2796–2800 (2018)]. The superposition reveals how the radiation torque associated with energy absorption can spin an object around its center of mass in a direction reversed with respect to the wave vortex’s handedness [L. Zhang, Phys. Rev. Appl. 10(3), 034039 (2018)]. These insights into extraordinary manipulations are of interest for advancing the flexibility of particle manipulations by acoustic tweezers and to the field of acoustofluidics.
Development of speech recognition in noise or two-talker speech: Context effects related to response alternatives and sentence meaning
Authors: Buss Emily , Leibold Lori
Published: April 2019

Speech recognition in normal-hearing adults is affected by pragmatic restrictions on the target content. For example, masked sentence recognition is better when target speech is composed of semantically meaningful compared to anomalous sentences. Similarly, masked word recognition is better when assessed in a close-set than an open-set task, even after accounting for changes in chance performance; this effect is most pronounced when the response alternatives in the closed-set task are acoustically distinct. In both the cases, restricting the set of plausible responses reduces the fidelity of acoustic cues necessary to perform the task. Although young school-age children benefit from this type of context, the magnitude of benefit relative to that observed for adults depends on the masker type. The benefit associated with increasingly restricted response alternatives is similar for young children and adults when the masker is noise, but young children derive little or no benefit when the masker is two-talker speech. Children and adults also differ with respect to the benefit of semantic context for sentences presented in noise or two-talker speech. Potential factors responsible for these developmental effects will be discussed, including maturation of auditory stream segregation, working memory, and acoustic/phonetic templates supporting word recognition.
A high-frequency model of a circular beam with a T-shaped cross section
Authors: Hull Andrew J. , Perez Daniel
Published: April 2019

This talk derives an analytical model of a curved beam with a T-shaped cross section for use in the high frequency range, defined here as approximately 1 kHz to 50 kHz. The T-shaped cross section is composed of an outer web and an inner flange. The web in-plane motion is modeled with two-dimensional elasticity equations of motion, and the left portion and right portion of the flange are modeled separately with Timoshenko shell equations. The differential equations are solved with unknown wave propagation coefficients multiplied by Bessel and exponential spatial domain functions. These are inserted into constraint and equilibrium equations at the intersection of the web and flange and into boundary conditions at the edges of the system which produces 24 linear algebraic equations. These are solved to yield the wave propagation coefficients and this gives a corresponding solution to the displacement field in the radial and tangential directions. An example problem is formulated and compared to solutions from fully elastic finite element modeling. The accurate frequency range of this new model compares very favorably to finite element analysis up to 50 kHz. This new analytical model is over 3 magnitudes faster than the corresponding finite element models.
Decreasing the radiated acoustic and vibration noise of autonomous underwater vehicles
Authors: D'Spain Gerald L. , Zimmerman Richard , Rimington Dennis , Jenkins Scott A.
Published: April 2019

An outstanding challenge in ocean engineering is decreasing the radiated acoustic and vibration noise of autonomous underwater vehicles (AUVs) while transiting at high speed. At low speed below 4–5 kt, our previously published results for both a modified mid-size, prop-driven AUV and a large (30 liter) buoyancy driven glider demonstrate that, with proper engineering, own-platform-created noise levels recorded by hull-mounted hydrophone arrays can be decreased below typical background ocean noise levels across the frequency band above a few hundred hertz. Below this frequency, the remaining noise is primarily vibration induced. Recent efforts have focused on decreasing propulsion noise at high speed from prop-driven platforms. Since buoyancy can be changed only over a very short portion of the dive cycle, buoyancy-driven propulsion systems provide an alternative approach to achieving low-self noise, high-speed, underwater flight. However, vibration and flow noise created by hydrodynamic forces still can present challenges at low frequencies. [Work supported by the Office of Naval Research and BP.]
Implant location in type 1 thyroplasty for unilateral vocal fold paralysis: Measurements from excised canine larynges
Authors: Maddox Alexandra , Farbos de Luzan Charles , Oren Liran , Khosla Sid M. , Gutmark Ephraim
Published: April 2019

Patients with unilateral vocal fold paralysis (UVFP) complain of a soft breathy voice that is hard to understand. Thyroplasty Type 1 (TT1), the most common surgical intervention for UVFP, uses an implant to push over the membranous fold. There remains controversy regarding TT1 procedures. Questions include the optimal shape and size for the implant, where to place the implant and whether an arytenoid adduction should be added. Despite several studies, no optimal technique has been found, and the revision rate has reported to be as high as 12%–25%. This study aims to understand the impact of implant location on vocal fold vibration. TT1 procedures were performed on excised canine larynges using silastica implants placed either at the glottis or just below the glottis to medialize the folds. Larynges were then made to phonate at various subglottal pressures (Psg), and measurements were taken of the acoustics, supplied flow rate, and Psg. From these measurements, the glottal efficiency was calculated, and the acoustic signal was analyzed to determine the quality of the sound source. On average, larnges medialized in the subglottis had higher glottal efficiency and cepstral peak prominence than those medialized at the glottis, indicating that lower implant location is preferable.
Flow characteristics as a function of velopharyngeal gap size
Authors: Rollins Michael , Oren Liran
Published: April 2019

The classic paradigm for treatment of velopharyngeal insufficiency (VPI) is based on the assumption that the severity of the speech disorder correlates with the size of the velopharyngeal (VP) opening. However, several studies have documented that even small VP openings can cause significant speech distortion. To investigate the potential contribution of aeroacoustic sources to speech distortion in VPI-affected speech, we set out to determine how airflow characteristics change as a function of the VP gap size. To do so, a head and neck CT scan of a VPI patient sustaining the phoneme /z/ was obtained. From the CT scan, patient-specific phantoms of the upper airway were made extending from the glottis to the nasal and oral exits. Four phantoms were made: one with the original VP gap size and three with VP gap sizes artificially scaled by factors of 1.25, 1.5, and 2. Particle image velocimetry (PIV) was used to measure the velocity and turbulence fields along planar slices in each phantom. Average velocity fields for each VP gap size are presented, and the change in flow characteristics as a function of the VP gap size is discussed, along with the implications for aeroacoustic sources.
Acoustic measures of paraspeech in speakers with multiple sclerosis: A study of neuropsychological status and its role in diadochokinesis
Authors: Feenaughty Lynda
Published: April 2019

Paraspeech tasks are frequently incorporated in motor speech disorder assessments and include syllable diadochokinesis (DDK), the rapid repetition of alternating movements (Kent, 2015). DDK measures indicate movements of the oral articulators and may detect problems before specific functions such as speech are affected in neurodegenerative diseases such as multiple sclerosis (MS). Although there is growing appreciation from studies of various clinical populations that cognitive and speech motor processes influence or interact with one another (Kent, 2004), the impact of cognitive limitations of speakers with dysarthria on DDK performance is not well understood. Toward this end, the current study explored cognitive status as a factor in DDK performance for 48 speakers with MS and 12 healthy adults. All speakers were recorded as they repeated various syllables as quickly and steadily as possible. Standard acoustic criteria were used to obtain global and segmental temporal measures of DDK using speech analysis software. In addition, all speakers underwent rigorous cognitive testing (e.g., information processing efficiency). Because controversy continues over the use of DDK, this study sought to provide evidence for the clinical value of paraspeech in the assessment of motor speech disorders as well as cognitive status. [Work supported by the ASH Foundation and the University at Buffalo MDRF.]
Conversational turn-taking in youth at clinical high-risk for psychosis
Authors: Sichlinger Laura , Cibelli Emily , Goldrick Matthew , Mittal Vijay
Published: April 2019

Previous studies of speech abnormalities in schizophrenia reflect a consensus that atypical turn-taking behavior during conversation is a prominent feature of speech patterns in psychosis. However, the literature focuses on the population with formal psychosis and lacks studies that involve individuals who are at clinical high-risk (CHR) for developing a psychotic disorder. This study assessed the turn-taking performance of CHR youth to evaluate if abnormalities in turn-taking can be observed in the CHR population compared with controls and to investigate if turn-taking performance is correlated with symptom severity. While analysis of speech data from structured clinical interviews shows no significant group effects, high scores in attenuated psychosis symptoms were associated with significantly longer between turn pauses in the CHR population. This study adds to a growing body of literature that suggests that patterns of speech and linguistic features may be useful in detecting risk, and tracking clinical and treatment course across schizophrenia and spectrum disorders.
Predicting children's word recognition accuracy with two distance metrics
Authors: Brown Emma , Jamsek Izabela A. , Liang Laura , Holt Rachael F. , Bent Tessa
Published: April 2019

Children generally have more difficulty in recognizing words produced by talkers with unfamiliar regional dialects and nonnative accents compared to their home dialect, but the specific deviations from native norms that cause these word recognition decrements have not been quantified. This study examines the relation between word recognition accuracy and two distance metrics: phonemic pronunciation distance and holistic perceptual distance. To calculate phonemic pronunciation distances, sentences from six speakers representing different regional dialects (British and Scottish English) and nonnative accents (Japanese-, German-, Mandarin-, and Hindi-accented English) were phonemically transcribed and compared to transcriptions from speakers of the ambient dialect (Midland American English). Preliminary results show a relation between the phonemic pronunciation distances and children's word recognition accuracy for the sentences. Follow-up work will measure holistic perceptual distances through a ladder task in which listeners will rank a larger set of native and nonnative talkers based on the perceived distance to the home dialect, a measure that will capture both segmental and suprasegmental differences. Comparing the two distance metrics will provide mechanistic insight into the impact of extent and type of talker deviation from native norms on children's word recognition accuracy. [Work supported by National Science Foundation #17570 and Indiana University Hutton Honors College.]
Perception of prosody: How toddlers harness intonation to guide early attention
Authors: Thorson Jill C.
Published: April 2019

Young infants are born with language-specific preferences, particularly with respect to prosody (i.e., melody and rhythm). Previous work has shown that by 18-months, toddlers are guided by intonation and information status during an on-line reference resolution task (Thorson and Morgan, 14). This study isolated the role of fundamental frequency (f0) during early attentional processing, showing that a bitonal f0 movement increases looking time to a target over a monotonal movement (and both show increased looking versus no pitch movements). The motivation for the current study is to examine the ability to perceive and utilize specific intonational patterns at earlier stages in speech and language development. The study asks whether typically developing 14-month-old toddlers are able to employ different intonational contours in order to attend to an object with unique information statuses (e.g., new, given). Methods include monitoring eye movements in response to varying pitch patterns and analyzing variables such as total fixation time to a target and time of first fixation. We hypothesize that at this early stage, toddlers will exploit the prosodic system to fixate on the discourse salient target. Critically, this work is a precursor to analyzing the early perception of prosody in young children with autism spectrum disorders.
Temporal and spatial dependence of a yearlong record of sound propagation from the Canada Basin to the Chukchi Shelf
Authors: Ballard Megan S. , Sagers Jason D. , Badiey Mohsen , Colosi John A. , Turgut Altan , Pecknold Sean , Lin Ying-Tsong , Proshutinsky Andrey Y. , Krishfield Richard A. , Worcester Peter F. , Dzieciuch Matthew A.
Published: April 2019

During the Canada Basin Acoustic Propagation Experiment (CANAPE), low-frequency signals from five tomographic sources located in the Canada Basin were recorded by an array of hydrophones located on the Chukchi Shelf. The propagation distances ranged from 240 km to 520 km, and the propagation conditions changed from persistently ducted in the basin to seasonally upward refracting on the continental shelf. An analysis of the received level from the tomography sources revealed a spatial dependence in the onset of the seasonal increase in transmission loss, which was correlated with the locations of the sources in the basin. This observation led to the hypothesis that the water advected from Barrow Canyon westward over the continental slope by the Chukchi slope current contributes to the temporal and spatial dependence observed in the acoustic record. The water column properties and ice draft were measured by oceanographic sensors on the basin tomography moorings and by six arrays of oceanographic moorings on the continental shelf to characterize the temporal and spatial variability of the environment. This talk examines the range-dependent measurements and explains the observed variability in the received signals through propagation modeling. [Work sponsored by ONR.]
Seabed properties on the Chukchi Shelf observed during the 2016–-2017 canada basin acoustic propagation experiment
Authors: Sagers Jason D. , Ballard Megan S. , Pecknold Sean
Published: April 2019

Previous work examined seabed geoacoustical properties near the 150 m isobath on the Chukchi shelf as observed during the 2016–2017 Canada Basin Acoustic Propagation Experiment (CANAPE) [Sagers and Ballard, JASA 144(3), 1666]. That work reported a water/sediment compressional sound speed ratio near 0.98 and a compressional sound speed gradient in the upper sediment around 6 s-1. This work extends the prior analysis by investigating additional locations throughout the larger shallow-water experimental site. Data from subbottom profile surveys, measurements from an in situ acoustic coring system and inferences made using ship-radiated noise received on Autonomous Multichannel Acoustic Recorders (AMARs) deployed by the Defence Research and Development Canada (DRDC) are examined to understand seabed layering and sediment properties throughout the experimental region. Particular interest is given to understanding whether geoacoustical properties on the Chukchi shelf exhibit range-dependence. [Work sponsored by ONR.]
Impact sound isolation measurement analysis for 6 typical type of floors in China
Authors: Xue Xiaoyan , Li Hui , Yan Xiang
Published: April 2019

Single layer homogeneous elastic material floating floor, porous vibration isolation material floating floor, vibration isolation cube floating floor, spring floating floor, floor with hard finish topping, and floor with soft finish topping are 6 types of impact sound isolation floor commonly used in China. All the 6 types of floor are test in laboratory by both light impact method with standard tapping machine and heavy impact method with rubber tire and rubber ball. Data analysis is focused on one hand the difference between test methods for the same floor and the other hand the sound isolation performance of different floors by the same test methods.
A high-resolution goniometer to measure sound diffraction patterns
Authors: Savino Anthony , Kawasaki Jonathan , Xiang Ning
Published: April 2019

Surface scattering and diffuse reflections from acoustic diffusers have recently become a significant topic of research for room acoustics. An acoustical goniometer can be implemented to create a circular microphone array to characterize the polar response for various types of diffusers. Particular areas of interest include validating the Physical Theory of Diffraction (PTD) through the use of finite-sized diffusers. In order to properly describe this phenomenon, a microphone array must achieve a fine enough angular resolution in addition to fulfilling the far-field requirements. This talk will discuss the implementation and results of a portable goniometer with a radius of 5 m and an angular resolution of 1.25 deg. This design is intended to be easily deployed in empty, indoor spaces of sufficiently large dimensions for a full 360-deg diffraction response measurement.
Sex-differences in timing of the black-capped chickadee fee-bee song
Authors: Kobrina Anastasiya , Hahn Allison H. , Mercado Eduardo , Sturdy Christopher B.
Published: April 2019

Male black-capped chickadees produce fee-bee songs in spring for mate attraction and territorial defense. Less is known about the female song use in this species although a version of song, soft-song, appears to be used in mate-mate communication. Recent analyses of songs produced by chickadees revealed that female fee-bee songs are distinct from male songs in the spectral domain. Chickadees also precisely control the timing of their fee-bee songs during territory defense. No previous work has explored whether there are sex differences in the temporal patterning of fee-bee song production. Inter-song intervals were extracted from recordings of fee-bee songs produced in non-social contexts by 8 male and 7 female birds. Male chickadees produced fee-bee songs regularly, with the majority of songs spaced at intervals of 2.5–5.0 s. Song timing by females was more variable with production intervals ranging from 1.5 to 8.0 s. The relative stereotypy of song timing by males is consistent with earlier work suggesting that males may modulate song timing to communicate with other birds (e.g., by timing song production to either reduce or increase the likelihood that their songs overlap with those of other singers), and with differential use of songs by males and females.
Monaural edge pitch and models of pitch perception
Authors: Hartmann William M. , Cariani Peter , Colburn H. Steven
Published: April 2019

Noise with a sharp spectral edge produces a definite, perceived pitch. The pitch of lowpass noise lies slightly below the edge and the pitch of highpass noise slightly above it. The pitch shifts away from the edge, expressed in semitones, increase with the decreasing edge frequency. A neural timing model based on positive peaks of the autocorrelation function accounts for the broad features of the shifts. So, does a place model based on the peak of an excitation pattern as enhanced by lateral inhibition. As the edge frequency decreases below 150 Hz, the pitch persists for a lowpass noise but disappears for highpass noise. This result is consistent with the timing model but not with the place model. For high edge frequencies, the pitch is stronger for highpass noise than for lowpass noise—consistent with both timing and place models. As the edge frequency approaches 5000 Hz, the pitch disappears for most listeners, but for some listeners, a pitch persists for edge frequencies beyond 8000 Hz. The latter result argues against a timing model. It appears that both timing processes (low edge frequency) and place processes (high edge frequency) are required to explain the edge pitch. [Work supported by the AFOSR and the NIDCD.]
Overview of acoustical levitation for volumetric visual displays
Authors: Andersson Carl , Ahrens Jens
Published: April 2019

Acoustical levitation is an area with many applications ranging from medical drug delivery to micro-particle sorting. An application which has gained attention recently is the creation of volumetric displays by using small levitating objects. Advances in inexpensive ultrasonic phased arrays have increased the availability of dynamically controllable beamformers which enables the manipulation of the levitating objects in time and space. This allows for interpreting the levitating objects similarly to pixels in a normal display yet with an additional spatial dimension. Most implementations so far are based on the so-called Gor'kov formulation of radiation force. This formulation coupled with numerical optimization allows for calculation of the phases of the individual elements in the array. By exploiting symmetries in the solution, it is possible to impose an acoustic trap signature phase pattern onto simple focusing methods. Using off-the-shelf mid-air ultrasonic haptics systems to provide multiple focus points to which the phase patterns are applied allows for real-time control of multiple levitating objects. Current systems are limited to a handful of individually controllable objects so visualization is limited to abstract information. We present an overview of the state-of-the-art and discuss limitations and possibilities. [Work supported by Horizon 2020, No. 737087.]