bluuebunny/crossref_metadata_2025 huggingface dataset:
Physiological measurements of acoustic trauma following blast-induced traumatic brain injury (TBI) in laboratory mice
Authors: Burke Kali , Manohar Senthilvelan , Salvi Richard J. , Dent Micheal L.
Published: November 2019

Exposure to a high intensity blast from the detonation of improvised explosive devices (IEDs) can lead to a traumatic brain injury (TBI) and concurrent trauma to major auditory structures. Research on whether this trauma is permanent or temporary has been inconclusive due to heterogeneity of injury acquisition. A blast wave system that generates consistent and controllable blast waves has been developed, allowing for investigation into the co-morbidity of auditory damage and TBI. In this study, the effects of blast exposure on auditory brainstem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs) in male and female mice were measured. ABRs and DPOAEs were collected prior to exposure to a blast to represent the baseline auditory capacity of each individual subject. Mice were tested at 3, 30, and 90 days after the exposure to capture initial trauma and the degree of recovery. A shift in ABRs and DPOAEs thresholds was observed in post-exposure mice, indicating trauma to central and peripheral auditory systems. Following the 90 day tests, brains and cochleae were collected for further analysis. [Work supported by R01DC016641.]
Multilevel objective measures of interaural phase difference detection
Authors: Smith Spencer , So Won
Published: November 2019

Sensitivity to interaural phase difference (IPD) cues is critical for localizing sound and hearing in background noise. Recent work from multiple laboratories has explored electrophysiologic methods for assaying IPD sensitivity with the aim of developing an objective measure of binaural hearing. Such a measure would be useful in a variety of clinical and research applications such as understanding the effects of aging on binaural hearing; fine-tuning hearing aids/cochlear implants to maximize binaural benefit; and assessing neural damage after a traumatic brain injury. Here, we present data from an ongoing study evaluating a novel “multi-level” (brainstem, midbrain, and cortex) simultaneous measure of IPD acuity. Amplitude modulated (20, 40, and 80 AM) carrier tones (125, 250, and 500 Hz) with IPDs embedded in them (7 deg–180 deg) were used to generate auditory evoked potentials in young, normal hearing listeners. Neural responses corresponding to the carrier tones (frequency following responses), amplitude modulation envelopes (envelope following responses), and cortical change detection (acoustic change complex) were measured simultaneously to provide a multi-level snapshot of neural IPD processing. Parametric data presented here demonstrate feasibility and limitations of this approach for measuring IPD encoding at multiple levels of the auditory system.
The multisensory benefit of informative sound in visual task performance
Authors: Bruder Alexandra L. , Edworthy Judy , Schlesinger Joseph , Rothwell Clayton
Published: November 2019

Auditory alarms are relied upon to provide cues for industries with high-risk, multisensory performance tasks such as health care. In an anechoic chamber, anesthesiology residents (N = 25) were tested in a simulated multi-task setting, including a patient monitoring primary task with alarmed events, and a visual vigilance task. Alarm type was varied between conventional (following the International Electrotechnical Commission Standard 60601-1-8) and a novel auditory icon alarm, which provide additional information about the event causing the alarm. Novel alarm usage led to a 37% increase in vigilance accuracy and 160 ms reduction in response time, implying that the use of auditory icon alarms can provide multisensory benefits. These findings suggest that novel auditory icons help individuals by reducing the cognitive burdens of primary tasks through reducing visual search of the patient monitoring display. Therefore, auditory alarms help to reduce visual demand through offering cues to change; attention can be focused through the recognition of specifically encoded characteristics of audiovisual objects. These findings advocate for reconsideration of alarm type usage in favor of novel alarms, especially in high-stakes environments to potentially improve patient safety and outcomes.
Measurement of turbulent boundary layer unsteady wall pressures beneath elastomer layers of various thicknesses on a plate
Authors: Smith Cory J. , Capone Dean , Brungart Timothy A.
Published: November 2019

The attenuation of turbulence induced wall pressure fluctuations through elastomer layers was studied experimentally and analytically. Wall pressure statistics were measured downstream from a backward facing step, with no elastomer present and beneath 2, 3, and 4 mm thick elastomers in a water tunnel facility. The step height, h, was 0.635 cm, and the wall pressures were measured at non-dimensional distances of x/h = 10, 24, 36 and 54 downstream from the step. The attenuation of the wall pressure spectra beneath the elastomer layers that was measured experimentally was then compared to analytical model predictions. An analytical elastomer transfer function, which models the transfer of turbulent boundary layer wall pressures on the surface of an elastomer to the normal stresses through the elastomer, was applied to the turbulent boundary layer wall pressure spectra measured in the absence of an elastomer layer and compared to spectra measured beneath the 2, 3, and 4 mm thick elastomers. The attenuation of the turbulent boundary layer wall pressure spectra through the elastomer layer using the analytical elastomer transfer function was in excellent agreement with the attenuation measured experimentally through all thicknesses of elastomer and at all free stream velocities at which the experiments were performed.
A quantitative model of talker normalization by native and non-native speakers
Authors: Chen Si , Zhang Caicai , Lau Puiyin , Yang Yike , LI Bei , Fung Wing Kam
Published: November 2019

Talker variability affects native and non-native speakers in speech perception of segmentals (e.g., Bent et al., 2010) and suprasegmentals (e.g., Wong and Diehl, 2003). Zhang and Chen (2016) reported that gender-specific F0 range may contribute significantly to Cantonese tone perception. However, a full understanding of how the population F0 distribution affects tone identification is missing. This study aims to bridge this gap by modelling tone distributions and testing how deviated distribution parameters affect tone identification by native and non-native speakers. Statistical modeling of a Cantonese speech corpus of 68 speakers showed that F0 values of three Cantonese tones follow skew-normal distributions with three parameters: location, shape, and scale. We proceeded to conduct two experiments with 28 Cantonese and 28 Mandarin listeners using both naturally produced tones by 34 Cantonese speakers and manipulated tones with F0 values generated from simulated distributions. A multinomial mixed effects model revealed significant main effects of location and shape parameters. Locally weighted scatterplot smoothing curves also differed dramatically between native and non-native listeners, indicating an effect from long-term F0 distribution representations on tonal identification. The results thus offer useful insights about how parametric representations of phonetic distributions is used in tone identification.
“No” versus “Aniyo”: Back vowel diphthongization in heritage Korean
Authors: Cheng Andrew
Published: November 2019

The effects of a second language on a speaker’s first language phonology are well documented (e.g., Chang, 2013), and much has been done work specifically for heritage language speakers (Polinsky and Kagan, 2007; Montrul, 2010, 2015), who may be bilingual to some degree but are dominant in the majority language. Bilingualism research has identified “separate but nonautonomous phonological systems” (Paradis, 2001) in bilingual children, but few studies address heritage speakers’ phonological systems in relation to ongoing sound change (Konopka and Pierrehumbert, 2010). The current study examines F1 and F2 of the back vowels /o/ and /u/ in samples of read Korean speech from a population of Korean American Californians who identified as natively bilingual and/or heritage speakers of Korean. Forty speakers read short conversational passages in Korean during a bilingual interview. Preliminary results indicate that the heritage speakers’ /u/ vowel shows influence from California English, with greater F2 on average than their central /a/ vowel. The /o/ vowel also has a much lower F1 than expected given Korean’s canonical five-vowel system. Ongoing analysis examines the trajectory of both vowels to determine the influence of California English diphthongized back vowels on Korean monophthongs, and accent perception of the speakers’ Korean.
The influence of lexical characteristics and talker accent on the recognition of English words by speakers of Korean
Authors: Choi Minkyoung , Holliday Jeffrey J. , Munson Benjamin
Published: November 2019

A number of recent studies have examined whether English-language learners (ELLs) and native speakers of English (NS) show the same effects of lexical (word frequency [WF] and phonological neighborhood density [PND]) and indexical (speaker accent) factors on word recognition accuracy and speed. The motivation behind this work is to understand how different types of linguistic knowledge emerge over the course of learning an L2. Two recent studies, Imai et al. (2005) and Yoneyama and Munson (2017) used nearly identical methods and stimuli with two groups of ELLs: those whose first language (L1) was Spanish (Imai et al.) and those whose L1 was Japanese (Yoneyama and Munson), and found very different effects of PND on word-recognition accuracy. In this project, we use the methods reported by Imai et al. and stimuli on a third group of ELLs, those who L1 was Korean. In a preliminary report on this project (Choi et al., 2018), we found evidence that the Korean L1 ELLs performed more similarly to the Japanese L1 ELLs in Yoneyama and Munson. However, these conclusions were based on data from a small group of relatively high-proficiency ELLs. In the current study, we report the results of a larger group of ELLs, including lower-proficiency individuals.
Effects of speech-shaped noise on consonant identification by native and non-native Korean and English listeners
Authors: Choi Minkyoung , Munson Benjamin , Davies-Venn Evelyn E.
Published: November 2019

The global proliferation of machine-human interface via voice and audio suggests a growing need for including language-specificity in the design and implementation of acoustic signal processing devices for all individuals, especially those in educational settings. Second language learners are often more susceptible to acoustic distortions in their second language (i.e., L2). Speech understanding challenges that L2 learners face in noisy environments are often compounded by other normal cross-language influences that are expected to occur during L2 speech perception. This study evaluated consonant confusion patterns using consonant-vowel (CV) English tokens spoken by native Korean and English speakers. The speech stimuli were embedded in speech-shaped noise with varying signal-to-noise ratios. Speech scores were measured using an alternative forced-choice paradigm. Overall scores were evaluated for each listener group to first assess whether L2 learners were most robust to acoustic-variances in English when spoken by Korean compared to English native-speakers. Second, their speech scores and acoustic recordings were evaluated for constructive as well as destructive effects of these acoustic variance on their masking and consonant confusion patterns. Results will be presented on the similarity and differences in acoustics and perception between English and Korean native-speakers. The clinical implications of our findings will be discussed.
First-language effects on the production of Mandarin-accented English diphthongs: Insights from the perceptual assimilation model
Authors: Kim Boram , Chen Wei-Rong , Whalen D. H. , Reed Stefanie
Published: November 2019

Previous studies found that non-native vowel categorization can be explained by the Perceptual Assimilation Model (PAM), based on perception experiments. However, fewer production studies have been carried out to further support the findings. Here we examined English monophthongs and diphthongs produced by Mandarin learners of English (MAE), compared with those produced by native American English (AE) Speakers, based on the articulatory and acoustic data in an electromagnetic articulometry (EMA) corpus [Berry and Johnson, 2014, ICASSP] with 20 MAE and 20 AE speakers. Monophthongs were examined at mid-point and diphthongs at nine equally-spaced time points (i.e., every 10% of a total vowel duration). Our preliminary results reveal that PAM-predicted perceptually assimilated vowel categories (i.e., vowel pair/contrast not exist in L1, such as the /i-ɪ/ contrast in AE) were indeed produced as a single category with large articulatory overlap. Further, if the English diphthong has a counterpart in Mandarin, it undergoes L1 transfer; if not, it is produced as a sequence of two monophthongs. For example, the English /aɪ/ can be categorized in Mandarin diphthong /aɪ/ but English /ɔɪ/ does not exist in Mandarin; and /aɪ/ produced by MAE underwent reduction as in native Mandarin diphthong but /ɔɪ/ did not.
Comparison of decadal low-frequency ambient noise trends measured in the northern Pacific Ocean: ATOC and CTBTO systems
Authors: Andrew Rex , Stafford Kathleen , Dall'Osto David R.
Published: November 2019

Trend estimates from 25 Hz to more than 50 Hz collected from 1994 to 2018 in the north Pacific Ocean are compared. The majority of trends derived from Acoustic Thermometry of Ocean Climate (ATOC) systems over nearly two decades, starting at roughly 1994, suggest a decrease in ambient noise levels of up to 1 dB/year. This is observed on both coastal and deep ocean systems. (Datasets from the remaining systems show either no change or an increase.) Measurements from the Comprehensive Test Ban Treaty Organization (CTBTO) system at Wake Island from 2008 to present provide an overlap from 2008—2013. The CTBTO data streams are essentially continous, and can be averaged and/or aggregated over a variety of time scales. Daily averages show a distinct seasonal cycle. From 2008 to about 2014, the underlying trends are decreasing by as much as 0.55 dB/year, corroborating some of the ATOC observations; from 2014 to the present, the trends are essentially flat. The mechanisms driving these trends appear to be more subtle than the local wind speed or merchant fleet size.
Enabling technology to extend life and utility of hydroacoustic systems
Authors: Elliott Ryan R. , Reardon John
Published: November 2019

The existing infrastructure of the six CTBTO Hydroacoustic System spans remote locations of the world. The first of these systems is reaching its 20 year life and consideration to the maintenance and replacement of the systems is ongoing. This presentation will discuss opportunities to incorporate advancements in active junction box design, facilitating the inclusion of wet-mate underwater fiber optic connections in any future upgrade, replacement, or repair of these systems. Recent analysis of the in-water triplet has shown that these units are likely to last much longer than the 20 year life objective. During any future maintenance or repair, the inclusion of a junction box with wet-mate fiber optic connectors could help to improve the serviceability of the system and could provide opportunity to expand the system to new co-located science research.
Identifying fish sounds of British Columbia with an autonomous audio and video array
Authors: Mouy Xavier , Black Morgan , Cox Kieran , Qualley Jessica , Juanes Francis , Dosso Stan E.
Published: November 2019

Among the ∼400 marine fish species of British Columbia, only 22 have been reported to be soniferous. However, it is likely due to the lack of examination, as more species are suspected to produce sound. Here we describe how an autonomous audio and video array can identify fish sounds in situ. The array is composed of a collapsible PVC frame, an acoustic recorder, six hydrophones, and two custom-made wide-angle autonomous video cameras mounted on the top and side of the array that collect data continuously for up to 10 days. Fish sounds are automatically detected in the acoustic recordings, the time difference of arrivals between pairs of hydrophones is measured by cross correlation, and the 3-D sound-source location and its uncertainty are estimated using linearized inversion. Simulated annealing optimization was used to define the hydrophone configuration that provides the smallest localization uncertainties. The video recordings are used to assign the species of sound-producing fish localized within the array. The array was deployed at several locations around Vancouver Island and used to define the species, sound characteristics, and source levels of several fish sounds. This new information will help making passive acoustics a viable way to monitor fish in the wild.
Localization and tracking of fish sounds with a 4-element underwater passive acoustic array
Authors: Pagniello Camille , D'Spain Gerald L.
Published: November 2019

Localization and tracking are parameter estimation problems. As such, estimates are evaluated by their statistical distribution, in particular, their bias (equal to the mean of estimated positions minus the true position) and variance (variability in the measured positions about their mean). A variety of methods are used to localize sounds recorded by acoustic arrays. Here, we quantitatively compare the performance of four algorithms: (1) plane-wave-front frequency-domain beamforming; (2) curved-wave-front frequency domain beamforming; (3) time-difference-of-arrivals (TDOAs) using waveform cross-correlation; and (4) TDOAs using spectrogram cross-correlation, for fish sounds generated with a controlled underwater source at various GPS-located positions around a 4-element array. The array consisted of a SoundTrap ST4300 (Ocean Instruments, Auckland, NZ) four-channel acoustic recorder, equipped with four HTI-96-MIN hydrophones (High Tech, Inc., Long Beach, MS). The hydrophones were arranged in a tetrahedral-shaped configuration with a 20-m inter-element spacing. The objective is to optimize the localization and tracking of individual soniferous fish to better understand their small-scale spawning movements and reproductive behavior. Research supported by the Office of Naval Research, the Scripps graduate department, and a Natural Sciences and Engineering Research Council of Canada (NSERC) Postgraduate Scholarship-Doctoral (PGS D-3).
A case study on Bornean gibbons highlights the challenges for incorporating individual identity into passive acoustic monitoring surveys
Authors: Clink Dena J. , Klinck Holger
Published: November 2019

Passive acoustic monitoring (PAM) has the potential to revolutionize how we study vocal animals, given recent advances in battery life, data storage capabilities and design of recording devices. A major obstacle to the wide-spread implementation of terrestrial PAM programs—particularly with respect to density estimation—is the difficulty in effectively discriminating between calling individuals. Using PAM, identity can be inferred based on caller location or on individually distinct call features. Here, we report the results of a two-month intensive acoustic survey of two gibbon groups in Sabah, Malaysia. We aimed to (1) test a novel acoustic localization method and (2) test how relative distance of recorders to the vocalizing animal, along with recording day and time, influenced our estimates of the call features important for individual identification. We were able to localize calling individuals from within our array with relatively high accuracy, but localization was less accurate at the edges of the array. We found that features estimated from the spectrogram remained relatively stable across recording distances and conditions, whereas Mel-Frequency Cepstral Coefficients were more variable. Our results have important implications for scalability of PAM programs, and based on our results we provide recommendations for incorporating individual identity into PAM programs.
Filter optimization for orthogonal frequency division multiplexing combined with multi line transmission for ultrafast ultrasound imaging
Authors: Song Yue , Ramalli Alessandro , Boni Enrico , Demi Libertario
Published: November 2019

Multi-line transmission (MLT) and orthogonal frequency division multiplexing (OFDM) are two types of approaches which have been individually applied to increase ultrasound data acquisition rate. Both consist in the simultaneous transmission of several beams to reconstruct multiple image lines at the same time, which, however, implies interbeam cross-talk that deteriorates image quality. In particular, as a consequence of interbeam cross-talk, imaging artifacts are generated. While MLT essentially relies on beams spatial-separations to limit interbeam cross-talk, OFDM mitigates interbeam-cross-talk by assigning to each beam a fraction of the transducer bandwidth. Recently the combination of the two techniques has been tested and shown effective to further boost the data acquisition rate [doi:10.1109/ULTSYM.2018.8580107]. In this work, results from a filter optimization study are reported and discussed. Data as obtained from wire targets and tissue mimicking phantoms have been analysed to asses the impact of filter type, order and bandwidth on key imaging features, i.e., axial resolution, interbeam cross-talk, and artifacts area. The ULA-OP 256 system equipped with a 2.4 MHZ phased array was employed to collect the data.
Multi-pulse, plane-wave acoustic contrast agent imaging with a 16 MHz linear array
Authors: Ketterling Jeffrey A. , Silverman Ronald H.
Published: November 2019

Plane-wave imaging allows high-frame rates, and with high-frequency (HF) ultrasound, fine-spatial and temporal resolution. HF, plane-wave multi-pulse (MP) imaging methods of acoustic contrast agents (UCAs) are still an unexplored area for small-animal and small-parts imaging. The MP methods of pulse inversion (PI, + 1 and -1 pair) and amplitude modulation (AM, + 1 and + ½ pair) were compared to standard plane-wave compound imaging for a flow of the UCA Definity in a linear-channel, wall-less flow phantom using a 16-MHz linear array. Transmissions were made at -10, 1 and 10 deg. Definity was diluted in water to 2000:1 and a flow was established through the phantom. Beamformed data were processed to find RMS values in a flow and background region in order to calculate contrast-to-noise ratio (CTR). The MP methods resulted in an 8 dB improvement in CTR relative to standard plane-wave imaging. The absolute intensity of the flow and background regions dropped for PI and AM relative to standard plane-wave imaging. At all acoustic drive pressures, PI and AM CTRs were statistically different than with standard imaging (p < 10-4). PI and AM CTRs were statistically different above 1 MPa (p < 10-4) where PI had a 3 dB higher CTR.
Frequency content of shear wave pulses excited by acoustic radiation force
Authors: Barbone Paul E.
Published: November 2019

Ultrasound shear wave elastography uses shear waves to infer the viscoelastic properties of soft tissues. Since soft tissues tend to exhibit dispersive behavior, it is important to standardize the frequency at which measurements are reported. Shear wave pulses excited by acoustic radiation force in different materials, however, do not have the same frequency content, even if the radiation force pulse has precisely the same characteristics. Here, we present a simple model for shear wave pulse creation by acoustic radiation force. This model explains the frequency content of the acoustic radiation force pulse and can therefore be used to design radiation forcing parameters to obtain a desired frequency content in a given material. To derive our model, we use separation of time-scales to show that the shear wave pulse propagation may be treated as an initial value problem. The combination of the (particle) initial velocity distribution and the tissue mechanical properties determines the resulting frequency content of the shear wave pulse.
Architectural Acoustics: From Auditoria to Zoos
Authors: Jaramillo Ana M.
Published: November 2019

The Technical Committee in Architectural Acoustics deals with sound in the built environment. Any type of building requires consideration of sound during the design process. In some cases, sound quality is very important (e.g., concert halls), in others, sound clarity is essential for speech communication (e.g., classrooms) and in some, the presence of unwanted sound can be detrimental (e.g., hospitals). All of these scenarios are considered by architectural acoustics. Because of the broad range of applications, TCAA often crosses interests with other Technical Committees. Noise, Musical Acoustics, Psychological and Physiological Acoustics are some of the most common ones to hold joint sessions with and have research and application interests in common. As TCAA is one of the largest ones in the Society, it also has a great number of subcommittees dedicated to specific topics such as Classroom Acoustics or Green Buildings. The committee members are also varied, with a good mix of academics, industry and practitioners, as well as students.
The Technical Committee on Physical Acoustics: Who are we and what do we do?
Authors: Gee Kent L. , Keppens Veerle M.
Published: November 2019

The Technical Committee on Physical Acoustics (TCPA) of the Acoustical Society of America (ASA) includes scientists and engineers interested in the underlying physics of acoustical phenomena or in using acoustic waves to study the physical properties of matter. TCPA is broad: computational, experimental, and analytical methods are used across the entire frequency range—from infrasound through ultrasound—to study wave propagation through liquids, solids, and gases. This presentation introduces new students to some of the facets of TCPA and its intersection with other ASA technical areas.
Soundscape and smart growth
Authors: Brooks Bennett M. , Schulte-Fortkamp Brigitte
Published: November 2019

Smart growth principles are increasingly being applied to urban developments, in order to increase the quality of life for residents, workers and visitors in a locale. A key component which contributes to the personal experiences of those occupants is the acoustical environment. The soundscape technique is a powerful tool for determining existing conditions, and for developing positive design and planning outcomes. Therefore, it is important that soundscape be incorporated with smart growth principles, to achieve the full potential for improvement in each development. A review of smart growth principles is presented. The relationship of these principles to soundscape analysis is examined.
Making cities smarter with new soundscape indices
Authors: Mitchell Andrew , Aletta Francesco , Oberman Tin , Erfanian Mercede , Kachlicka Magdalena , Lionello Matteo , Kang Jian
Published: November 2019

The core objectives of smart city design are to increase quality of life, enhance efficiency, and move towards the sustainability of cities. While this will involve increased integration of new and smarter technologies into urban design, the implementation of these technologies as applied to acoustics should be made within a design approach which considers these core objectives. Soundscape strategies have a focus on people’s perception and experience, considering the many factors which influence their perception. A recognized demand in the field of soundscape is a new set of metrics that can reliably measure both the acoustic environment and its perception. The European Research Council acknowledged this need and recently funded the Advanced Grant project “Soundscape Indices” (SSID), which aims at providing more advanced tools, compared to conventional dB-based metrics, by taking into account psychological, (psycho)acoustical, neurophysiological, and contextual factors for soundscape assessment. The SSID project will: characterise soundscapes, by capturing acoustic environments and establishing a comprehensive database; identify key factors and their influence on soundscape quality based on the database, by conducting laboratory psychological evaluations, acoustical/psychoacoustic factors analysis; and research the neural and psychophysiological underpinnings of soundscape experience. It is expected that SSID will provide a vital tool in guiding the implementation of the technological infrastructure of smart cities.
The temporary hearing thresholds shifts in fitness instructors
Authors: Dudarewicz Adam , Zaborowski Kamil , Pawlaczyk-Luszczynska Malgorzata , Wolniakowska Anna , Sliwinska-Kowalska Mariola
Published: November 2019

Noise in the entertainment industry often reaches high sound pressure levels. The aim of this study was to analyze the temporary threshold shifts (TTSs) of hearing among fitness instructors. The study comprised a total of 30 fitness instructors working in fitness clubs. The noise dosimeters were used to determine individual noise exposure during exercises conducted by the instructors. To assess the TTS values, the pure tone audiometry tests were performed before and just after the exercises. The observed TTSs were compared with the predicted TTSs according to the computational model developed by Melnick (1991). Typical fitness exercises lasted from 1 to 2 h and A-weighted equivalent-continuous sound pressure level ranged from 75 to 96 dB. Temporary threshold shifts after the sound exposure were statistically significant. The actual values of TTS fitted well with the values predicted with the TTS computational model. The results show that the computational TTS model gives results consistent with the TTS observed in the study group. Fitness instructors constitute a population at an increased risk of the hearing loss. Raising awareness of this fact and implementing hearing protection programs in this group of workers are urgently needed.
Broadband suppression of total multiple scattering cross section using neural networks
Authors: Pornaras Don Robert L. , Wang Wei-Ching , Chen Yanru , Kwak Grace , Amirkulova Feruza , Khatami Ehsan
Published: November 2019

We will demonstrate a novel method to simulate acoustic multiple scattering by a configuration of cylinders and solve inverse problems using artificial neural networks (NN) and deep learning. We will research how to apply deep learning to solve inverse design problems efficiently. Solving inverse design problems using optimization requires an iterative process of function evaluations and determining gradients, which are computationally expensive. In this work, forward multiple scattering problems are solved first by means of multiple scattering theory to provide training data for NN. Then, NN are trained to approximate the total scattering cross section (TSCS) function using backpropagation algorithm; the input of NN is positions of the cylinders, and the output is the TSCS evaluated at discrete values of wavenumber. Finally, trained NN are employed to solve inverse problems. Specifically, the TSCS by a plane configuration of cylinders is minimized over a range of wavenumbers using trained NN. A suppression of the TSCS can lead to the efficient design of broadband acoustic cloak. This method will be illustrated giving examples for a plane configuration of rigid cylinders.
Vibration characteristics of a car using transfer path analysis
Authors: Falasifah Nihlatul , Arifianto Dhany
Published: November 2019

Vibration is a common issue in the automobile system, especially in an old car. Several causes that may generate vibration are vibration at idle and engine RPM. Vibration can decrease the ride comfort and become one of the contributing factors that cause an accident or emergency condition. Therefore, vibration evaluation to know the vibration characteristics of the classic car must be conducted to diagnose when and under what condition the vibration occurs. This paper aims to know the vibration level and vibration characterization of the classic car from car engine as the vibration source to some selected positions at low-frequency engine idle speed by using Transfer Path Analysis (TPA). This research used a 1991-manufactured car. Finite element calculation, simulation, and experimental modal analysis were used to determine the dynamic characteristics of the car for the natural frequencies. The natural frequencies that generated from the experimental modal analysis are convoluted by operational acceleration when the car engine was turning on which equal to operational force as transfer path analysis. In conclusion, TPA can be used to know the vibration characteristics in Noise Vibration and Harshness (NVH) issues by tracing the flow of vibration using operational force.
Investigations into the accuracy of the light damping approximation
Authors: Liem Alyssa T. , McDaniel James G.
Published: November 2019

This presentation surveys a variety of representative case studies in an effort to better understand and predict the accuracy of the light damping approximation. For viscously damped systems, the light damping approximation ignores the off-diagonal elements of the transformed damping matrix. When the approximation is valid, it presents profound advantages for numerical simulations. The most obvious of these is uncoupling of the equations of motion. A less obvious advantage is the ability to estimate the viscous damping matrix from a knowledge of the modal loss factors and undamped eigenvectors. The presentation begins by defining error metrics for quantifying the accuracy of the approximation in time and frequency domains. Next, case studies are designed to understand how statistical properties of the structure control the accuracy of the approximation. These investigations make two fundamental contributions. The first contribution is the knowledge required to estimate the accuracy of the approximation without significant computational expense. The second contribution is identification of statistical properties that are important to the construction of model libraries used in training machine learning algorithms.
Mapping the global prey-field: Combining acoustics, optics and net samples to reduce uncertainty in estimates of mesopelagic biomass
Authors: Proud Roland , Kloser Rudy J. , Handegard Nils Olav , Cox Martin J. , Brierley Andrew S.
Published: November 2019

Mesopelagic (200–1000 m depth zone) biomass largely comprises zooplankton, jellyfish, squid and fish. Part of this biomass actively migrates between the surface and the mesopelagic zone on a daily basis, playing an important role in global biogeochemical cycling. When observed using echosounders, aggregated components of this community (largely made up of fish and siphonophores) are known as Deep Scattering Layers (DSLs). DSLs have been used to partition the Global Ocean into biogeographically distinct regions, based on DSL vertical distribution and echo energy, and estimates of mesopelagic biomass have stemmed from this work. These estimates are typically derived using a combination of biological sampling, optics, and active-acoustics, but are often biased (e.g., through trawl-based escapement and avoidance) and uncertain. We have developed a new method that combines multiple strands of observations, both from vessels and ocean probes, to minimise sampling bias and produce accurate estimates of mesopelagic biomass. We apply the method to the specific case of estimating mesopelagic fish biomass in the Tasman Sea, combining observations made from a vessel and a Profiling Lagrangian Acoustic Optical System. We compare our new biomass estimates to previous estimates and ecosystem model predictions. Our new method provides a robust framework for future ocean biomass estimates.
Human beatboxing : A multi-instrumental pilot
Authors: Dehais Underdown Alexis , Vignes Paul , Crevier-Buchman Lise , Demolin Didier
Published: November 2019

This comparative study aims to describe laryngeal, acoustic, and aerodynamic characteristics of instrumental imitations that is the beatboxed classic kick drum [pã] and snare drum [pëÀ] (PF-snare) by one artist. Beatboxed sounds were produced in isolation and in beatboxed patterns. Aerodynamic (intraoral pressure, oral airflow, and nasal airflow), acoustic, electroglottographic, and laryngoscopic data were acquired. Laryngeal and aerodynamic data show that the classic kick drum is produced as a bilabial voiceless glottalic egressive plosive [p] or as a bilabial voiceless glottalic egressive affricate [pè¡]. The PF-snare was produced as a labial voiceless glottalic egressive affricate [pëÀf]. Sounds in isolation were shorter than those in a pattern. Acoustic analysis revealed high amplitude burst for all realizations that is consistent with ejective realization (i.e., high increasing intraoral pressure). Spectral analysis shows a peak in the low frequencies for [p] as well as for [pëÀf]’s onset but when turning to the fricative offset [f], we noted a peak in high frequencies and a flattening spectrum. Based on the acoustic and aerodynamic data, we discuss the coordination of the articulators and the planification of articulatory commands of the classic kick drum and the PF-snare drum.
A real-time magnetic resonance imaging study of cross-speaker variability in the production of /ɹ/
Authors: Godinez Bianca P. , Toutios Asterios , Narayanan Shrikanth S.
Published: November 2019

There is a longstanding interest in understanding the production mechanisms of the American English (AE) rhotic, /ɹ/ especially given both the wide intraspeaker variability and interspeaker heterogeneity in its articulation, and the resultant acoustics. A diversity of tongue shapes, from those creating a more anterior tongue-tip (“retroflex”) constriction to those with a more posterior bunched tongue dorsum constriction, has been observed with notable intraspeaker variation as a function of context; more specifically, a tendency for retroflexion preceding low and/or back vowels. The present study aims to analyze AE /ɹ/ production using real-time MRI videos (83 frames/s) where the target sound was produced in several contexts by 32 American English speakers (16 F/16 M). Initial findings in symmetric VCV production reveal that some of these speakers exclusively use a “retroflex” strategy, some a “bunched” strategy, and others both strategies, consistent with the previously observed tendencies. This observed variability, and the fact that multiple types of static and dynamic imaging data are available from the same speakers, makes this dataset ideal for further probing /ɹ/ production strategies in conjunction with speaker-specific characteristics of vocal tract structure, such as palate shape, and function, such as inter-articulator coordination. [Work supported by NIH and NSF.]
Intrinsic fundamental frequency of Amharic vowels
Authors: Van Doren Maxine
Published: November 2019

Intrinsic fundamental frequency (IF0) refers to the cross-linguistic tendency for high vowels to have a higher F0 than low vowels (Whalen and Levitt, 1995). IF0 is often thought to be a result of mechanical coupling, where tongue movement causes changes in the laryngeal structures, perturbing the F0. Ohala and Eukel (1987) propose that high vowels lead to increased vertical tension on the true vocal folds, which raises F0. In contrast, the tongue-compression hypothesis proposes that low vowels induce vocal fold slackening, which lowers F0 (Ewan, 1979). The purpose of the present study is to investigate the cause of IF0 by comparing high, mid, and low vowels in Amharic, using audio and EGG signals to measure F0 and contact quotient for different vowel heights. Amharic was chosen because it contrasts three heights of central vowels. The goals are to confirm that IF0 effects are found in Amharic and determine if voice quality changes further support either hypothesis. Discussion will focus on how F0 and contact quotient differ by vowel height, and whether the results support the tongue-pull hypothesis (where IF0 is driven by high tongue position), the tongue-compression hypothesis (where IF0 is driven by low-back tongue position), or both.
Improving passive acoustic monitoring applications to the endangered Cook inlet beluga whale
Authors: Zhong Ming , Castellote Manuel , Dodhia Rahul , Lavista Ferres Juan , Keogh Mandy , Brewer Arial
Published: November 2019

A decade after the Cook Inlet beluga was listed as endangered in 2008, its population has shown no signs of recovery. Lack of ecology knowledge limits our understanding of, and ability to manage, potential threats impeding recovery of this declining population. NOAA Fisheries, in partnership with the Alaska Department of Fish and Game, initiated a passive acoustics program in 2017 to monitor beluga seasonal occurrence by deploying a series of acoustic moorings, followed by months’ work of manual validation for the detectors' output. To reduce this labor intensive and time-consuming process, we extracted a series of spectrograms from the sound files containing validated detections, and built 4 deep learning convolutional neural networks (CNN) with fine tuning of parameters. The final model is an ensemble of these individually optimized models, and achieves 96.57% precision and 92.26% recall on testing data. As a comparison, current detectors tend to trigger more false positives, which result in 20%–60% precision when human noise is present and 85%–95% precision in quiet areas. Following the success of the model with its easy generalizations to other acoustic detection problems, our next step will be comparing results from non-validated raw data to adopt this updated analysis process.
Toward Understanding Youth Athletes’ Fun Priorities: An Investigation of Sex, Age, and Levels of Play
Authors: Visek Amanda J. , Mannix Heather , Chandran Avinash , Cleary Sean D. , McDonnell Karen A. , DiPietro Loretta
Published: November 2019

Colloquial conjecture asserts perceptions of difference in what is more or less important to youth athletes based on binary categorization, such as sex (girls vs. boys), age (younger vs. older), and level of competitive play (recreational vs. travel). The fun integration theory’s FUN MAPS, which identify 11 fun-factors comprised of 81 fun-determinants, offers a robust framework from which to test these conceptions related to fun. Therefore, the purposes of this study were to scientifically explore: (a) the extent to which soccer players’ prioritization of the 11 fun-factors and 81 fun-determinants were consistent with the gender differences hypothesis or the gender similarities hypothesis, and (b) how their fun priorities evolved as a function of their age and level of play. Players’ (n = 141) data were selected from the larger database that originally informed the conceptualization of the fun integration theory’s FUN MAPS. Following selection, innovative pattern match displays and go-zone displays were produced to identify discrete points of consensus and discordance between groups. Regardless of sex, age, or level of play, results indicated extraordinarily high consensus among the players’ reported importance of the fun-factors (r = .90–.97) and fun-determinants (r = .92–.93), which were consistently grouped within strata of primary, secondary, and tertiary importance. Overall, results were consistent with the gender similarities hypothesis, thereby providing the first data to dispel common conceptions about what is most fun with respect to sex, in addition to age and level of play, in a sample of youth soccer players.
Genome Sequences of Human Coronavirus OC43 and NL63, Associated with Respiratory Infections in Kilifi, Kenya
Authors: Kamau Everlyn , Luka Martha M. , de Laurent Zaydah R. , Adema Irene , Agoti Charles N. , Nokes D. James
Published: November 2019

Coding-complete genomes of two human coronavirus OC43 strains and one NL63 strain were obtained by metagenomic sequencing of clinical samples collected in 2017 and 2018 in Kilifi, Kenya. Maximum likelihood phylogenies showed that the OC43 strains were genetically dissimilar and that the NL63 strain was closely related to NL63 genotype B viruses.
Draft Genome Sequence of the Halophilic Pararhodobacter-Like Strain CCB-MM2, Which Has Polyhydroxyalkanoate-Synthesizing Potential
Authors: Sam Ka-Kei , Lau Nyok-Sean , Furusawa Go , Amirul Al-Ashraf Abdullah
Published: November 2019

Pararhodobacter
-like strain CCB-MM2 is a halophilic alphaproteobacterium isolated from estuarine sediment collected from Matang Mangrove Forest in Malaysia. Here, we present the draft genome sequence of CCB-MM2 and provide insights into its physiological roles and metabolic potential.
How does spending time outdoors protect against myopia? A review
Authors: Lingham Gareth , Mackey David A , Lucas Robyn , Yazar Seyhan
Published: November 2019

Myopia is an increasingly common condition that is associated with significant costs to individuals and society. Moreover, myopia is associated with increased risk of glaucoma, retinal detachment and myopic maculopathy, which in turn can lead to blindness. It is now well established that spending more time outdoors during childhood lowers the risk of developing myopia and may delay progression of myopia. There has been great interest in further exploring this relationship and exploiting it as a public health intervention aimed at preventing myopia in children. However, spending more time outdoors can have detrimental effects, such as increased risk of melanoma, cataract and pterygium. Understanding how spending more time outdoors prevents myopia could advance development of more targeted interventions for myopia. We reviewed the evidence for and against eight facets of spending time outdoors that may protect against myopia: brighter light, reduced peripheral defocus, higher vitamin D levels, differing chromatic spectrum of light, higher physical activity, entrained circadian rhythms, less near work and greater high spatial frequency (SF) energies. There is solid evidence that exposure to brighter light can reduce risk of myopia. Peripheral defocus is able to regulate eye growth but whether spending time outdoors substantially changes peripheral defocus patterns and how this could affect myopia risk is unclear. Spectrum of light, circadian rhythms and SF characteristics are plausible factors, but there is a lack of solid evidence from human studies. Vitamin D, physical activity and near work appear unlikely to mediate the relationship between time spent outdoors and myopia.