bluuebunny/crossref_metadata_2025 huggingface dataset:
The relation between production and perception of Mandarin tone
Authors: Leung Keith K. W. , Wang Yue
Published: October 2018

This pilot study explores the potential production-perception relation of Mandarin tones by examining the association between the acoustic features of native Mandarin tone production and perception of such features, using Tone 2 (rising tone) as a testing case. The perception stimuli were resynthesized by varying F0 onset (spectral feature) and F0 turning-point location (temporal feature) orthogonally forming a grid of tone contours. The endpoints of these dimensions were determined by natural Tone 1 and 3 productions, presumably corresponding to perceptual boundaries for Tone 2. A parabola was fitted to the resynthesized tones to determine the overall shape of the tone contour. Native Mandarin participants were asked to identify the best exemplar of Tone 2. The acoustic analysis of Tone 2 productions by the same participants included measurements of the same features. Preliminary correlation analysis showed a positive production-perception correlation for the temporal feature of F0 turning-point location, but no significant correlation for the spectral features of F0 onset and F0 contour shape, indicating F0 turning-point location as a critical perceptual cue for Tone 2. Further research will include additional tones and additional acoustic features found to characterize these tones to identify the nature of production-perception relation of Mandarin tones.
Categorical perception of Mandarin tones by Cantonese trilingual children
Authors: Li Shiyue , Chen Si , Chan Angel
Published: October 2018

It is generally argued that children’s tone perception gradually becomes adult-like after age 6. In addition, previous studies suggest that stimulus duration, vowel quality, and musical training significantly contribute to categorical perception of pitch directions in both tonal and non-tonal language (Chen et al., 2017; Zhao & Kuhl, 2015). However, little is known about how musical training may shape categorical perception of trilingual children, and how stimulus duration and vowel quality come into play. In this paper, we investigate these effects on the categorical perception of Mandarin tones based on Cantonese trilingual children. Specifically, we created rising and falling Mandarin continua on high and low vowels with three duration values. Based on some pilot data, the vowel quality plays a vital role in the categorical perception of rising tones but not in the falling tone pitch directions. Children with professional musical training show much more categorical perception than children without musical training. Specifically, musically trained children show more between-category discrimination than within-category discrimination. Moreover, they are more sensitive to stimulus and are faster in terms of reaction time. Our findings will be compared with previous studies on categorical perception by adults and all significant effects will be discussed.
Sub-articulatory interactions in palatalization processes
Authors: Cavar Malgorzata E. , Lulich Steven M.
Published: October 2018

Palatalization is a widespread phenomenon across the world’s languages and is typically conceived articulatorily as a tongue body raising and/or fronting gesture that is spread from high and/or front vowels to neighboring consonants. Oddly, palatalization of labial consonants (which allow the greatest degree of gestural overlap with neighboring high and/or front vowels) is typologically least common, suggesting that palatalization processes do not primarily result from gestural overlap, but instead arise from the resolution of incompatible lingual “sub-articulations.” In particular, articulatory data from Polish and Russian palatalized consonants point to a critical role for tongue root interactions with tongue blade and dorsum gestures. The products of these resolved sub-articulatory interactions can become lexicalized and reconfigured by later generations of language-learners in response to the interaction of phonological pressure to maintain contrasts and new palatalization processes. The etymological history of the Proto-Slavic stems *menk- and *ment- illustrates these interactions. The velar consonant in *menk- was palatalized by a following high, front vowel to a “soft” posterior affricate. Subsequently, the coronal consonant in *ment- was palatalized as well (Modern Polish mącić). To maintain the contrast between the sound categories, the palatalized velar was reconfigured as a post-alveolar “hard” consonant (męczyć).
Comparing acoustic and articulatory targets in short-term visual feedback training of non-native vowels
Authors: Mehta Sonya , Katz William F.
Published: October 2018

Theories of speech production aim to explain how talkers express abstract linguistic forms as audible events that are intelligible to both speaker and listener. The relationship among planned units of speech, their articulatory implementation, and their acoustic consequences is thus a key issue in speech research. The work reported here is part of a larger project designed to investigate the effects of visual acoustic and visual articulatory feedback on second language (L2) learners’ production and perception of non-native speech sounds. L2 talkers from a variety of language backgrounds practiced producing an English vowel, /æ/, while receiving visual feedback on either (1) first and second formant frequencies, provided by a real-time spectrographic display, or (2) tongue back position, shown using a talker-driven tongue avatar. Kinematic data were recorded using an electromagnetic articulograph (EMA) system that tracked tongue midline and lateral movement during vowel productions. Pronunciation accuracy was analyzed by calculating acoustic and kinematic Mahalanobis distances between L2 productions and target (native talker) exemplars. Initial analyses of a single subject’s data showed that both types of visual feedback training improved pronunciation, suggesting that both acoustic and articulatory information are recruited during vowel production.
Lexically dependent estimation of acoustic information in speech
Authors: Redmon Charles , Jongman Allard
Published: October 2018

Current estimates of the relevant acoustic information in speech are typically inventory-based. They assume a set of phonemes or featural/gestural decompositions of phonemes exists in a language, and proceed to identify and rank/weight the set of acoustic parameters sufficient to distinguish a phonemic contrast based on data from instantiations of the sounds/categories comprising those contrasts in either a controlled set of real words in the language or in nonword syllables. Acknowledging that such contrasts ultimately derive from lexical oppositions, we present an alternative, complementary approach to the quantification of acoustic information in speech: one that is lexically based. Using acoustic data from the Massive Auditory Lexical Decision project (Tucker et al., 2018)—over 26,000 unique words produced by a single speaker of Western Canadian English—and listener identification data on a representative 240-word sample of that lexicon, we define a weighted network of the phonological lexicon (cf. Vitevitch, 2008), where the weights on links between minimal pairs correspond to the predicted acoustic similarity from a model fit to the listener error distributions. From this network the distributed, “global” information contributed by individual parameters operating in an ensemble of lexical oppositions can be estimated from changes in network entropy under perturbations of those parameters.
Linking production and perception of clear speech
Authors: Sereno Joan A. , Jongman Allard , Wang Yue , Hamarneh Ghassan , Tang Lisa , Garg Saurabh , Tupper Paul , McMurray Bob , Redmon Charles , Zeng Yuyu , Hannah Beverly , Leung Keith K. W. , Cho Sylvia
Published: October 2018

Speech communication can adopt different styles as a function of speaking environments and communicative needs. In auditorily or visually challenging contexts, speakers often alter their speech production using a clarified, hyper-articulated speech style with the intention of enhancing speech intelligibility. Such modifications may result in perceptible articulatory and acoustic changes. Questions thus arise as to whether and what clear-speech modifications facilitate perception. This presentation surveys recent research conducted in our labs, investigating clear-speech production and its associated effects on perception. In a series of three-stream studies, this research relates analyses of visible articulatory features using computer image-processing techniques, measurements of acoustic properties, and perceptual patterns of clear-speech segments and suprasegmentals by native and non-native perceivers. Results reveal that clear (relative to plain) speech modulates different and compensatory articulatory-acoustic cues within each sound category to enhance intelligibility. However, our results also show that clear-speech modifications that reduce phonemic category distinctiveness inhibit intelligibility. These findings indicate that clear-speech effects are governed by the collateral principles of within-category cue enhancement and maintenance of category distinctiveness.
Weak adaptation to foreign-accented voice-onset-time distribution
Authors: Biro Tifani , Shin Seulgi , Zeng Yuyu , Tremblay Annie
Published: October 2018

Listeners quickly adapt to foreign-accented speech in transcriptions and word/sentence judgments (Bradlow & Bent, 2008; Clarke & Garrett, 2004; Sidaras, Alexander, & Nygaard, 2009). However, continuous spoken-word recognition measures such as eye tracking have revealed limitations on foreign-accent adaptation. For example, Trude, Tremblay, and Brown-Schmidt (2013) found that English listeners’ adaptation to a second-order constraint in a Quebec French talker’s accent (/i/ = [ɪ] before coda consonants except voiced fricatives) was limited. This study investigates whether foreign-accent adaptation is less limited when the mapping between the accented and underlying words does not require higher-level inferencing. English listeners completed an eye-tracking experiment in which they heard a (female) French talker and a (male) English talker. Target and competitor words began with a voiced or voiceless stop and were otherwise temporarily ambiguous (e.g., timberand dimple). All stops were resynthesized: The French talker’s stops were prevoiced (voiced) and short-lag (voiceless) and the English talker’s stops were short-lag (voiced) and long-lag (voiceless). Preliminary results suggest an effect of voicing only for the French talker, with voiceless-stop targets generating more competition than voiced-stop targets. Importantly, this effect decreased only slightly from the first to the second half of the experiment, suggesting weak foreign-accent adaptation.
Use of tonal information in French and English listeners’ segmentation of Korean speech
Authors: Tremblay Annie , Shin Seulgi , Kim Sahyang , Cho Taehong
Published: October 2018

(Seoul) Korean has been analyzed as having an Accentual Phrase (AP) with a L(HL)H tonal pattern for APs beginning with a lenis segment (Jun, 1998). This tonal information modulates Korean listeners’ speech segmentation (Kim & Cho, 2009; Tremblay, Shin, Kim, & Cho, 2018). This study investigates whether French- and English-speaking late learners of Korean can also use this tonal information. French has similarly been analyzed as having an AP with a L(HL)H tonal pattern (Jun & Fougeron, 2002). In contrast, English words are often stressed initially (Cutler & Carter, 1987), with nuclear-pitch-accented words beginning with a H tone (Beckman, 1986). French, English, and Korean listeners completed an eye-tracking experiment. They heard sentences containing a temporary ambiguity between an AP-initial target (saesinbu-ga]AP[masul-eul ‘the-new-bride-subj magic-obj’) and a disyllabic competitor spanning the AP boundary (gama"palanquin"). Stimuli were resynthesized to orthogonally manipulate the AP-final and AP-initial tones (H/L). Results show that learners eventually used the AP-final and AP-initial tones like Korean listeners, but French listeners made earlier use of both tones than English listeners, even if the AP-initial tone is less crucial to French speech segmentation (Tremblay, Broersma, Coughlin, & Choi, 2016). Speech segmentation is thus very adaptive, even among late learners.
Identifying the distinctive acoustic cues of Mandarin tones
Authors: Tupper Paul , Leung Keith K. W. , Wang Yue , Jongman Allard , Sereno Joan A.
Published: October 2018

Using mathematical modeling, this study aims to characterize distinctive acoustic features of Mandarin tones based on a corpus of 1013 monosyllabic words produced by 21 native Mandarin speakers. For each tone, 22 acoustic cues were extracted. Besides standard F0, duration, and intensity measures, further cues were determined by fitting two mathematical models to the pitch contours. The first is a broken-line model, which models the contour as a continuous curve consisting of two lines with a single breakpoint. The second model is a parabola, which gives three parameters: a mean F0, an F0 slope, and an F0 curvature. Using Cohen’s d, we identify which of the 22 cues are important for distinguishing each tone from the others for all speakers, as well as identifying cues that are used idiosyncratically by particular speakers. Although the specific cues that best characterize each tone differ, we show that the three cues obtained by fitting a parabola to the tone contour are an effective small set of cues such that any pair of tones is well distinguished by at least one of them. We propose using these three cues as a canonical choice for defining tone characteristics.
Priming the representation of left-dominant sandhi words: A Shanghai dialect case study
Authors: Yan Hanbo , Chien Yu-Fu , Zhang Jie
Published: October 2018

This study examines how the acoustic input (the surface form) and the abstract linguistic representation (the underlying representation) interact during spoken word recognition by investigating left-dominant tone sandhi, a tonal alternation in which the underlying tone of the first syllable spreads to the sandhi domain. We conducted an auditory-auditory priming lexical decision experiment on Shanghai left-dominant sandhi words, in which each disyllabic target ([tɕi55 dɛ31] “egg”) was preceded by monosyllabic primes either sharing the same underlying tone ([tɕi55]), surface tone ([tɕi53] “machine”), or being unrelated to the tone of the first syllable of the sandhi targets ([tɕi24] “to remember”). Results showed a surface priming effect, but not an underlying priming effect. Moreover, the surface priming did not interact with speakers’ familiarity ratings to the sandhi targets. The results are discussed in the context of how phonological opacity, productivity, and the directionality of tone sandhi patterns influence the representation of tone sandhi words as well as how the lexicality of the primes and the participants’ usage pattern of Shanghai may have influenced the results.
Effect of proficiency on perception of English nasal stops by native speakers of Brazilian Portuguese
Authors: Alcorn Steven , Smith Irene , De La Cruz Luis , Smiljanic Rajka
Published: October 2018

Brazilian Portuguese (BP) does not contrast /m/ and /n/ in coda position, leading to perceptual difficulties with minimal pairs like lime/line in L2 English. This study examined the effect of acoustic-phonetic and semantic enhancements on word recognition in noise for native English (n = 26) and L1 BP/L2 English (n = 21) listeners. They heard 120 high- and low-predictability sentences produced in clear and conversational speaking styles and mixed with speech-shaped noise. They typed the last word ending in either /m/ or /n/. The L2 listeners were separated into high- and low-proficiency (HP and LP) groups based on the perceived accentedness ratings of speech samples they provided. The results showed that native listeners benefited more from semantic than acoustic-phonetic enhancements alone, and the accuracy was highest when both enhancements were combined. The HP L2 listeners recognized more target words overall than the LP group, and their benefit from semantic over acoustic-phonetic enhancements mirrored that of the native listeners. In contrast, LP listeners could not utilize the higher-level semantic information to the same degree in the absence of signal clarity. These findings show that L2 listeners benefited from acoustic-phonetic, semantic, and combined enhancements when recognizing /m/-/n/ coda pairs, but this effect was mediated by proficiency.
Recall of clearly spoken sentences
Authors: Keerstock Sandie , Smiljanic Rajka
Published: October 2018

Recognition memory (i.e., identifying items as old or new) is higher for sentences spoken clearly than for sentences spoken casually. The clear speech benefit on recognition memory was observed for both native and non-native English listeners. The current study investigated the effect of clear speech on sentence recall, a more complex and effortful type of declarative memory that requires processing at phonological, lexical-semantic, morphosyntactic, and syntactic levels. Thirty native and 30 non-native English listeners heard 72 meaningful sentences (e.g., “The grandfather drank the dark coffee”) produced in conversational and clear speaking styles by a female native English speaker. Participants were presented with 12 sentences blocked by speaking style, and instructed to memorize them. After each block of 12 sentences, participants wrote down what they remembered. Blocks were counterbalanced for speaking style. Responses were scored by number of keywords correctly recalled (verbatim memory) and sentence-level comprehension (gist memory). Preliminary results show enhanced verbatim memory for clear speech (i.e., higher rate of key words correctly recalled for sentences produced in clear speech) for both listener groups suggesting that hyper-articulated clear speech provides cognitive release and aids retention of surface form.
Correlation of biological and acoustical measurements of the endangered Golden Cheeked Warbler with applications of machine learning
Authors: Knobles David P. , Wilson Preston S. , O’Donnell Lisa , Hutchinson Darrell , Reiner William
Published: October 2018

Acoustic measurements on Setophaga chrysoparia (Golden-cheeked warbler) have been made within the 40,000 acre Balcones Canyonland Preserve (BCP) in Austin, TX, where the long-term goal is to understand the potential effects of anthropogenic noise on breeding success. The anthropogenic sources of noise include road traffic, jet aircraft, helicopters, and urban development and utilization. During the breeding season from March through May, acoustical recordings were made in dense Ash Juniper forests for 12 hours per day at 12 locations within the BCP. The evolution of the number of songs of Type A and B and their variants are signatures of breeding success. The study attempts to apply principle component analysis for feature selection input into a feedforward neural network classifier of the A and B signatures, their variants, and the ability to automate the identification of individual birds. A feedforward neural network attempts to parameterize a mapping y = f(x,θ) for input features and category pairs of the A and B signatures and parameterization θ. Explored is the sensitivity of the number of hidden layers required to learn the optimal parameterization θ approximating f. [Work supported by City of Austin.]
Clustering analysis of crowd noise from collegiate basketball games
Authors: Butler Brooks A. , Cook Mylan R. , Gee Kent L. , Transtrum Mark K. , Warnick Sean , Todd Eric , Larsen Harald
Published: October 2018

The relationship between crowd noise and crowd behavioral dynamics is a relatively unexplored field of research. Signal processing and machine learning (ML) may be useful in classifying and predicting crowd emotional state. As a precursor to performing ML, it is instructive to identify which crowd acoustic events an unsupervised ML algorithm would classify as unique. An initial set of audio features have been extracted from high-fidelity noise recordings of crowds at Brigham Young University men’s and women’s basketball games. A K-Means clustering analysis was conducted on half-second segments of the recordings using extracted features consisting of numerous statistical and spectral characteristics. For example, a clustering analysis performed on a one-twelfth-octave spectrogram of crowd noise recordings reveals there are approximately six unique events that occur during a game. The clusters for different audio feature sets are compared with human labeling of the different acoustical events. Implications for further ML algorithm development based on various sets of audio features are discussed.
Clustering analysis of inputs to a geospatial model of outdoor ambient sound
Authors: Butler Brooks A. , Gee Kent L. , Transtrum Mark K. , Pedersen Katrina , James Michael M. , Salton Alexandria R.
Published: October 2018

Outdoor ambient acoustical environments may be predicted through supervised machine learning using geospatial features as inputs. However, collecting sufficient training data is an expensive process, particularly when attempting to improve the accuracy of models based on supervised learning methods over large, geospatially diverse regions. Unsupervised machine learning methods, such as K-Means clustering analysis, enable a statistical comparison between the geospatial diversity represented in the current training dataset versus the predictor locations. In this case, the geospatial features that represent the regions of western North Carolina and Utah have been simultaneously clustered to examine the common clusters between the two locations. Initial results show that most geospatial clusters group themselves according to a relatively small number of prominent geospatial features, and that Utah requires appreciably more clusters to represent its geospace. Additionally, the training dataset has a relatively low geospatial diversity because most of the current training data sites reside in a small number of clusters. This analysis informs a choice of new site locations for data acquisition that maximize the statistical similarity of the training and input datasets. [Work funded by an Army SBIR.]
An experiment of air-to-water sound propagation in deep water
Authors: Wang GuangXu , Zhang LingShan , Peng ZhaoHui
Published: October 2018

The underwater sound propagation from an airborne source has been paid much attention recently. To explore the underwater sound propagation from an airborne source in deep water, an experiment was conducted in South China Sea. A vertical line array of hydrophones with depth from 100 meters to 3400 meters was anchored on the seabed to detect the sound of a loudspeaker. Two microphones were placed under the loudspeaker to measure the source level. Both continuous and linear frequency modulation wave signals with frequency from 100 Hz to 2000 Hz were transmitted by the loudspeaker. The distances between the loudspeaker and the vertical line array were from 5km to 14.5km. Comparing signal detected by underwater hydrophones with signal detected by microphones in air, transmission loss of is figured out. The transmission loss predicted by a wave number integration model OAST is compared with the experimental results.
Stochastic matched-field processing using polynomial chaos expansions to model environmental uncertainty
Authors: Oba Roger M. , Mignerey Peter C. , Finette Steven I.
Published: October 2018

A stochastic generalization of matched-field processing (MFP) is presented that incorporates stochastic steering matrices rather than steering vectors. This provides a natural framework for including environmental uncertainty associated with incompletely known environmental knowledge. Parametric probabilities allow use of polynomial chaos (PC) expansions to describe environmental uncertainty in a rigorous manner, yielding efficient representations of the stochastic steering matrices through the application of sparse sampling methods. In particular, PC methods apply to the uncertainty of sediment variability that can be modeled via horizontal spectral methods. With moderate variability over scales justified by data in the New Jersey shelf region, the sediment uncertainty can be modeled with relatively few PC expansion coefficients, which depend only on the mean amplitude of spectral components. The coefficients express the nonlinear dependence of the acoustic field on the sediment variability, essentially orthonormalizing higher moments. The coefficients lead immediately to stochastic steering matrices, which are then compared via various MFP processors against acoustic data for MFP source localization. [Work supported by the U.S. Office of Naval Research.]
Underwater ambient noise spatial and temporal coherence at basin scale
Authors: Kinda G. Bazile , Le Courtois Florent , Stéphan Yann , Boutonnier Jean-Michel , Royer Jean-Yves , Barruol Guilhem
Published: October 2018

Underwater soundscape may be seen as an intrinsic feature of the environment in which it is recorded. In fact, underwater soundscape is a complex combination of sounds from a variety of acoustic sources, whether from natural or from human origin. When the distances between the sources and the receivers are sufficiently large, the received signals are strongly modified by the acoustic response of a continuously fluctuating marine environment. Then, spatio-temporal characteristics of the environment can be inferred from the measurements of soundscapes from hydrophone networks. The presentation aims to assess the spatial and temporal coherences of low frequency underwater ambient noise in the Indian Ocean basin. The data under consideration combine year round acoustic recordings from two recoding systems: on the one hand, data were from ~50 Ocean Bottom Seismometers (OBS) arranged in a network as large as 2000 km x 2000 km (http://www.rhum-rum.net/); and on the other hand acoustic data from hydrophones in the SOFAR channel.
Parallel processing and machine learning for long-timescale ambient noise measurements—Illustration with data from the Neptune Ocean Observatory offshore British Columbia
Authors: Klein Amelie , Blondel Philippe , Heine Kari
Published: October 2018

Seafloor observatories are a rapidly maturing technological approach, enabling the monitoring of marine soundscapes over large areas (basin scale) and long timescales (10 + years). However, the time needed to process broadband measurements, especially over large periods, often acts as a bottleneck. This is particularly true when combining multi-resolution analyses with assessing the impacts of relatively short transients. We are using parallel processing to enable machine learning approaches. To accelerate the computation of spectrograms, we have implemented a parallel processing method that uses the FFT algorithm FFTW3 (http://www.fftw.org/fftw3.pdf), using MPI/C + + on the High Performance Computing facilities at the University of Bath, and compared with spectrogram calculations from well-established software PAMGuide (Merchant et al., Meth. Ecol. Evol. 2015), with Matlab’s Parallel Computing Toolbox. This approach was tested on 1 month of broadband (96 kHz) measurements from the NEPTUNE node at Folger Deep. One month of data can be processed in <3 hours, to a dB accuracy even on short time segments, and that performance increases with the number of parallel processing units. Stability of the parallel approach has been tested with synthetic signals (e.g., chirps) and increasing signal-to-noise ratios. This enables much faster monitoring of long-term trends of important sound metrics.
Upslope propagation of low frequency deep ocean signals
Authors: D'Spain Gerald L. , Houston Kenneth , Tingley Robert , Nawara Terry , Lawrence Daniel , Brovarone Thomas
Published: October 2018

Over the period 18–21 March, 2017, 1-hour waveforms in the 60–120 Hz band were transmitted from a HLF-6A source deployed at 300 m depth in the deep northeast Pacific Ocean. These transmissions were recorded by two vertical hydrophone line arrays at various ranges in the deep ocean, GPS-equipped sonobuoys deployed on the continental shelf, and a bottom-mounted hydrophone in 900-m water at the western edge of Monterey Bay operated by the Monterey Bay Aquarium and Research Institute (MBARI). Although the source-receiver ranges to the sonobuoys and the MBARI hydrophone were approximately the same, the bathymetry profile up the continental slope to the sonobuoy location was significantly steeper than to the MBARI hydrophone. Only the upper part of the frequency band, above 90–95 Hz, is received with good signal-to-noise ratio, illustrating the high-pass temporal filtering of upslope propagation. Upslope propagation also acts as a low-pass spatial filter, allowing only lower-order modes to propagate onto the shelf. Numerical modeling is used to examine the predictability of the measured travel times and multipath arrival structure.
The preliminary study on spatial correlation of ocean sound field
Authors: Weng Jin-bao , Yang Yan-ming
Published: October 2018

The sound field temporal correlation and spatial correlation, which are the foundation of the investigation of underwater signal space-time high-order characteristics, have important value in the underwater acoustic application. The spatial correlation is studied based on the shallow water acoustic propagation experiment data acquired in the northern South China Sea in 2017, and the deep water acoustic propagation experiment data acquired in the western Pacific in 2013. As for the explosive sound signals in shallow water, time domain waveform cross-correlation coefficients between signals from different propagation distance are calculated. In contrast, the linear frequency modulated signals in deep water need additional matched filtering. The signal processing results shows that, the overall spatial correlation is poor and the correlation radius is relatively small in shallow water, the convergence zone has an obviously better spatial correlation than the shadow zone for the deep water situation. The processing result is verified by simulation and analysis.
Excess attenuation caused by subducted bubbles at the ebb plume front in the Connecticut River
Authors: Reeder D. Benjamin , Joseph John E. , Rago Tarry
Published: October 2018

A field experiment was carried out in the Connecticut River in June 2017, one goal of which was to investigate the low-to-mid-frequency acoustic propagation characteristics of the fresh water plume front outside the river mouth during ebb. Linear frequency-modulated (LFM) acoustic signals in the 500-2000 Hz band were collected during several tidal cycles. Transmission loss in excess of that which is expected by sound speed gradient-driven refraction is explored via acoustic propagation modeling. The excess attenuation at the ebb plume front is attributed to large clouds of subducted bubbles by downwelling at the ebb plume front.
Temporal variability of propagation and reverberation during TREX13
Authors: Hefner Brian T. , Yang Jie , Tang Dajun , Hodgkiss William S.
Published: October 2018

During the Target and Reverberation Experiment in 2013, a bottom-mounted, mid-frequency source and horizontal line array were deployed on the seafloor to measure reverberation over the course of the experiment. Extending from the source and parallel to shore was the “main reverberation track,” a 7-km long and 1.5 km wide region where a majority of the acoustic and environmental measurements were made. Along this track, two vertical line arrays were deployed to continuously collect propagation data. The combination of the HLA and VLAs made it possible to make contemporaneous measurements of both transmission loss (TL) and reverberation level (RL) over a 3-week timespan. During this time, a storm passed through the site and the variability in the TL is found to be driven by different mechanisms. Prior to the storm, the variability was primarily driven by changes in the sound speed profile; after the storm, the water was well-mixed and the variability was a steady decay of TL while the rough sea surface decayed. This talk examines the variability in TL during these time periods and the associated changes in the measured RL. [Work supported by ONR.]
Range-dependent geoacoustic inversion for sound propagation in two seamounts environment
Authors: Pang Lichen , Hu Tao , Lu Licheng , Ren Qunyan , Ma Li
Published: October 2018

This paper presents a work of range-dependent geoacoustic inversion for two seamounts environment with negative gradient sound speed profiles based on the transmission losses (TLs), collected in an experiment in the South China Sea, 2016. Bombs of 200 m and the mooring vertical line array (VLA) is applied for recording. Typical characteristics of shadowing and reflecting by seamounts are confirmed by the fluctuations of TLs with respect to range, indicating the complexity of sound propagation within seamounts environment. In the framework of matched field inversion (MFI), the geoacoustic model of two layers and the range-dependent acoustic model (RAM) is applied to produce the replica TLs, which is used to compute the cost function in combination with the collected TLs in terms of the least mean variance. The simulated annealing (SA) is expected to augment the searching efficiency of geoacoustic parameters. Results of four models with different parameters within 120km are obtained, with which the simulated TLs are in good accordance with experiment results for several frequencies and receiving depths. Conclusion is drawn that the effects of range-dependence of geoacoustic parameters in seamounts environment are as important as those of bathymetry on sound propagation, which should be seriously considered especially with negative gradient sound speed profiles.
Analysis of the effect on the indoor acoustic comfort with the living surfaces in the design studio
Authors: Kocyigit Filiz B. , Yildirim Nazli N.
Published: October 2018

It is clearly shown in studies that acoustic comfort in the interiors play an effective role on directly increasing the productivity of users. Despite having the similar physical characteristics as the classrooms, design studios differ in terms of function and user behaviors. The training processes in the design studios have complicated function, but this process is limited in the classrooms. Recent research shows that living surface contribute to acoustical control at different frequencies, during the design periods at the studios. In these studies, living surfaces that provide indoor acoustic comfort are investigated in the general context. The effects of selected plants' structural differences on the indoor sound control at different frequencies are analyzed. Three different plants such as grass, moss, and aloevera are selected and their behaviors controlling the sounds of high, medium, and low frequencies in the indoor space are investigated. The behavior of these plants for the control of sounds in different frequencies in the studios has been examined. It is aimed to increase the educational efficiency of the users by using the combination of the most effective plant species in the studios' surface in terms of indoor acoustic comfort within the scope of the present data.
ATATÜRK's Sarcophagus Acoustic Properties
Authors: Kocyigit Filiz B.
Published: October 2018

This research investigates the acoustical characteristics of Atatürk sarcophagus. The Hall of Honor, which included the Atatürk's sarcophagus, was elevated from the whole mass, as it seemed strongly to the outside architect. The first floor is surrounded by this hall. The monument was built on a platform raised by six meters with a staircase in the direction of the square, with the ground closed and a massive wall with small windows, which was turned over with stone columns. The east entrance of the monument is at the beginning of the Aslan Road. At the beginning of this road, the entrance is strengthened by two guards, four meters high stairs are raised. When the monument is placed on the hill, two strong axes perpendicular to each other are taken as principal. Results, at the research, include equivalent sound pressure levels (Leq) as a function of location, frequency, and time of day. Special and important days like Revolution days are also researched. The spectra are generally flat over the 63–2000 Hz octave bands, with higher sound levels at lower frequencies, and a gradual roll off above 2000 Hz. Many units exhibit little if any reduction of sound levels in the nighttime.
Responses of the auditory system of odontocetes to level changes of long lasting acoustical stimuli
Authors: Sysueva Evgeniya , Nechaev Dmitry , Supin Alexander , Popov Vladimir
Published: October 2018

The effects of level changes of long lasting sound stimuli (tone pip trains) on evoked potentials (the rate following response, RFR) were investigated in a beluga whale (Delphinapterus leucas). The stimuli were of 64 kHz carrier frequency at levels from 80 to 140 dB re 1 μPa. During stimulation, the stimulus level either was kept constant (the steady-state stimulation) or was changed up/down by 20 or 40 dB every 1000 ms. After transition from a lower to upper stimulus level (increase), the response amplitude increased quickly and then decayed slowly. After transition from an upper to lower stimulus level (decrease), the response amplitude fell quickly and later recovered slowly. In the both cases, during the 1000 ms stimulus, the response amplitude almost reached that of the steady-state stimulus of the same level. The auditory system of the beluga (and, hypothetically, other odontocetes) may be characterized as quickly flexible and capable of quick adjustment of its responses to the current auditory scene. [This study was supported the Russian Science Foundation (Project No. 17-74-20107) awarded to E.V.S.]
Directional hearing sensitivity for 2–30 kHz sounds in the bottlenose dolphin (Tursiops truncatus)
Authors: Accomando Alyssa W. , Mulsow Jason , Branstetter Brian K. , Finneran James J. , Jenkins Keith
Published: October 2018

Bottlenose dolphins (Tursiops truncatus) depend on sounds with frequencies <30 kHz for social communication and foraging, but little information on the directional dependence of hearing thresholds for these sounds exists. This study measured behavioral hearing thresholds for 2, 10, 20, and 30-kHz tones projected from eight different angular positions around the dolphin in both the horizontal and vertical planes to determine whether the receiving beam at these frequencies was directional. Omni-directional hearing was hypothesized for sounds below 30 kHz, but this hypothesis was rejected. Results from two bottlenose dolphins demonstrated a positive relationship between directivity and the frequency of the test tone, with asymmetric beam patterns. Directional hearing sensitivity declined most dramatically between 10 kHz and 2 kHz. The results suggest that dolphins’ directional hearing is more pronounced for lower frequencies than previously predicted.
Stealthy moths avoid bats with acoustic camouflage
Authors: Neil Thomas R. , Shen Zhiyuan , Drinkwater Bruce W. , Robert Daniel , Holderied Marc W.
Published: October 2018

Intense predation pressure from echolocating bats has led to the evolution of a host of anti-bat defences in nocturnal moths. Some have evolved ears to detect the ultrasonic biosonar of bats, yet there are many moths that are completely deaf. To enhance their survival chances, deaf moths must instead rely on passive defences. Here, we show that furry morphological specializations give moth bodies and wing joints acoustic stealth by reducing their echoes from bat calls. Using acoustic tomography, echo strength was quantified in the spatial and frequency domains of two deaf moth species that are subject to bat predation and two butterfly species that are not. Thoracic fur determines acoustic camouflage of moths but not butterflies. Thoracic fur provides substantial acoustic stealth at all ecologically relevant ultrasonic frequencies, with fur removal increasing a moth’s detection risk by as much as 38%. The thorax fur of moths acts as a lightweight porous sound absorber, facilitating acoustic camouflage and offering a significant survival advantage against bats.
Effects of numbers of repetitions, repetition rate, frequency separation, and frequency range on auditory streaming in budgerigars (Melopsittacus undulatus)
Authors: Cai Huaizhen , Screven Laurel A. , Dent Micheal L.
Published: October 2018

Auditory streaming has been widely investigated behaviorally and physiologically in animals. The paradigm used in European starlings (Sturnus vulgaris) by MacDougall-Shackleton and colleagues (1998, J. Acoust. Soc. Amer.) was used here in budgerigars (Melopsittacus undulatus) to measure the effects of different numbers of repetitions of HLH- (high and low tones) triplets, repetition rates, tone frequencies, and frequency separations between the two tones on auditory streaming. Similar to humans, budgerigars subjectively experienced the auditory streaming phenomenon; more repetitions of HLH- triplets, faster repetition rates, and larger frequency separations enhanced the streaming perception. Further, these results were consistent across the two frequency ranges used in this study. When increasing the numbers of HLH- repetitions, it took longer to establish the streaming perception in budgerigars, similar to the buildup phenomenon in humans. These results indicate, for the first time using a behavioral paradigm, that budgerigars experience auditory streaming in a manner similar to humans.
Data assimilation for oceanographic and acoustic forecasting
Authors: Bhatt EeShan C. , Schmidt Henrik
Published: October 2018

Data assimilation relates observed physical data with dynamic modeling to provide a joint estimate of a field of interest that is bounded by input error. Here, a modular data assimilation framework is introduced for acoustic and sound speed field estimation with a discussion on streamlining separate and varied oceanographic data sources into previously established four-dimensional acoustic modeling. This methodology is applied to acoustic and physical data from an experiment in the Santa Barbara Channel, where passing cargo ships served as sources of opportunity, and a sensitivity analysis for acoustic transmission due to changing sound speed fields is presented. [Work supported by ONR under the Information in Ambient Noise MURI.]
Cell quake elastography
Authors: Cloutier Guy , Grasland-Mongrain Pol , Zorgani Ali , Nakagawa Shoma , Bernard Simon , Paim Lia Gomes , FitzHarris Greg , Catheline Stefan
Published: October 2018

The ability to measure the elasticity of a cell provides information about its anatomy, function, and pathological state. Many techniques have been proposed to measure mechanical properties of single cells but most need a model of the cell characteristics and the fixation of the cell on a substrate. Moreover, current measurements take seconds to hours to perform, during which biological processes can modify the cell elasticity. Here, we have developed an alternative technique by applying shear wave elastography to the micrometer scale. Elastic waves were mechanically induced in live mammalian oocytes using a vibrating actuator. These audible frequency waves were observed optically at 205,000 frames per second and tracked with an optical flow algorithm previously developed in the context of ultrasound elastography. Whole-cell elasticity was then reconstructed using an elastography method inspired by the seismology field. Using this approach we showed that the elasticity of mouse oocytes is decreased when the oocyte cytoskeleton is disrupted with cytochalasin B. The technique is fast (less than 1 ms for data acquisition), precise (spatial resolution of a few micrometers), and able to map internal cell structures. The proposed method may represent a tractable option for interrogating biomechanical properties of diverse cell types.
Mechanical biomarkers by torsional shear ultrasound for medical diagnosis
Authors: Rus Guillermo , Melchor Juan M. , Faris Inas , Callejas Antonio , Riveiro Miguel , Molina Francisca , Torres Jorge
Published: October 2018

The WHO estimates that 15 million babies yearly (1 in 10) will be born preterm. Worldwide, complications of preterm births have supplanted pneumonia as the primary cause of child mortality [1]. The biology of cervical ripening that leads to birth is poorly understood, and there is no clinical tool to quantitatively evaluate the cervical biomechanical state, which in words of Feltovich [2]“… likely contributes to the reason the singleton spontaneous preterm birth rate has not changed appreciably in more than 100 years.” Towards this problem, we work on enabling new sensor technologies sentient to soft tissue biomechanics, to endow a new class of biomarkers that quantify the mechanical functionality of the cervix, and indeed any soft tissue, ranging pathologies from tumors, atherosclerosis, liver fibrosis to osteoarticular syndromes. Ultrasonic characterization of soft tissue has been developed as a clinical diagnostic tool [3] and evolved through different technologies including our torsional wave principle [4]. Our recent advances covering (a) torsional waves (shear elastic waves that propagate in quasifluids radially and in depth in a curled geometry), (b) sensors (based on a novel arrangement of concentric sandwiches of elements), (c) propagation models and (d) patient testing, are allowing to quantify the mechanical functionality beyond linear parameters: dispersive and nonlinear. [1] WHO, 2012; [2] Feltovich. AJOG207(2012):345–354 [3] Barr. Ultras Quart28(2012):13–20; [4] Melchor. Ultrasonics, 54(2014):1950–1962.
Validation of single-element ultrasound targeting in the brain for human neuromodulation
Authors: Blackmore Joseph , Braun Verena , Butler Christopher , Cleveland Robin
Published: October 2018

Non-invasive brain stimulation techniques allow for excitation or inhibition of neural activity via externally applied stimuli through the skull. Recently, ultrasound has been shown to stimulate neurons with better spatial localization than existing electrical stimulation modalities and has subsequently been employed in several human neuromodulation studies. While increased focality provides the potential for modulation of specific brain targets, the overlying skull bone can distort the ultrasound beam leading to shifting and fragmentation of the focus. Consequently, care must be taken to ensure the ultrasound focus is coincident with the intended brain target to confirm the induced effects are due to direct ultrasound activation. Here, we present numerical simulations using k-Wave and experimental measurements demonstrating focusing to different areas of the visual cortex using ex-vivo human skulls with single-element transducers. We show that targeting of many areas can be achieved without the use of lenses or arrays. The sensitivity of transducer angle and location on the resultant pressure field within the skull is assessed along with comparisons between MRI and CT datasets and elastic and fluid-based simulations. Finally, we also explore correction methods for targeting areas of the brain through more complex skull topologies, for example, through the petrous ridge.