bluuebunny/crossref_metadata_2025 huggingface dataset:
Signal-to-interference plus noise ratio loss constrained robust adaptive beamformer inpsired by random matrix theory
Authors: Richmond Christ D.
Published: December 2020

The optimal adaptive beamformer (ABF) maximizing output signal-to-interference plus noise ratio (SINR) has filter weights that depend on the data covariance and signal array response vector. The effectiveness of practical application of this optimal beamformer, however, is limited by (i) data stationarity (needed for covariance estimation), and (ii) knowledge of the true signal array response vector. Robust ABF attempts to address these two critical issues via a slight reformulation of the ABF problem, and often result in some form of diagonal loading yielding a hybrid beamformer that engages the tradespace between conventional beamforming (CBF) and ABF. The joint distribution of a CBF power spectral estimate and an ABF estimate based on the same data covariance reveals that estimates have a statistical coupling governed by the geometric cosine between their filter weights, i.e., the SINR loss between CBF and ABF. Thus, a robust ABF algorithm is proposed that constrains the SINR loss to an acceptable level while minimizing beamformer sensitivity to signal array response errors. This is practically appealing since this allows the user to specify the minimum SINR loss tolerable, and the resulting robust ABF solution uses the available degrees of freedom to reduce sensitivity to signal array response errors.
Subjective perception of hospital environments with varying dynamic ranges of noise
Authors: Bliefnick Jay , Ryherd Erica E.
Published: December 2020

Individuals may perceive noise stimuli differently based on the content of the source, due to factors such as the frequency spectra, level, temporal characteristics, or even the dynamic range of the noise source (the range of sound levels from quietest to loudest in a given sample). Results from earlier phases of this research indicated subject preference for quieter overall environments with a larger dynamic range of noise (based on the analysis of noise Occurrence Rates within real hospital units). In this phase of the study, a subjective perceptual laboratory test was designed and administered to 33 subjects to assess the annoyance perception of noise stimuli with varying dynamic ranges. Simulated hospital environments were utilized as the source stimuli, selected to represent a “typical” hospital unit patient area. It was found that in a controlled setting, subjects perceived noise stimuli with a wider dynamic range and louder peak noise events more negatively than noise sources with more consistent sound levels.
A bio-inspired acoustic detector of mosquito sex and species
Authors: Ziemer Tim , Koch Julia , Sa-Ngamuang Chaitawat , Yin Myat Su , Siai Mahmoud , Berkhausen Benny , Efe Deniz
Published: December 2020

Mosquitoes mostly use their auditory system to recognize species and sex of other mosquitos. This has been proven based on behavioristic and neurologic experiments. This ability is amazing, since most of the frequencies that mosquitos create lie outside their own hearing range. It is evident that they do not respond to the frequencies themselves, but to nonlinear distortion products and combination tones between their own wing beat sound and the sound of other flying mosquitos. Based on mechanical, acoustical and neurological considerations, we are creating an analogue model of the mosquito's plumose antenna to calculate the afferent neural activity evoked by the scolopidia in the Johnston's organ when exposed to sound. The model successfully creates some of the nonlinearities that help mosquitoes identify sex and species of other mosquitoes. The model output can serve as a bio-inspired feature for automatic classification of mosquito sex and species. Applying machine learning with conventional audio features from the field of speech recognition and music information retrieval we observed good species discrimination abilities. However, we believe that bio-inspired features for mosquito species and sex recognition are more robust against environmental noise. Thus, they can contribute better to fighting malaria, dengue fever and other mosquito-borne diseases.
Ultrasonic tomograph for reconstruction of spatial distributions of sound speed and absorption coefficient
Authors: Zotov Dmitriy , Dmitriev Konstantin , Rumyantseva Olga
Published: December 2020

Ultrasound tomograph designed to reconstruct spatial distributions of sound speed and absorption coefficient in soft biological tissues (primarily in mammary gland) is presented. Distinctive feature of the tomograph is sparse annular antenna array with irregular arrangement of receiving-transmitting transducers. When an object is tomographed by its layers, 26 transducers in combination with antenna rotation allow providing the same data set as in case of nonrotating array with 256 transducers. Two-step processing algorithm uses both ray methods to reconstruct large-scale details of the required spatial distributions and wave methods to reconstruct small details. High degree of algorithm parallelism allows to reduce the time of experimental data processing by CUDA GPUs to several minutes per an image layer. Results of processing both model data and experimental data obtained for phantom objects are presented. Disadvantages of reconstruction at the first step of the algorithm with low resolution (0.5–1 cm) are analyzed. The high resolution (not worse than 1 mm), achieved at the second step of reconstructing the small details is illustrated. It is shown that these small details, which are the most informative for medical diagnostics at early stage of neoplasm, cannot be reconstructed without preliminary reconstruction of large-scale details.
Improving detection of bone surface defects using modified delay-multiply-and-sum reconstruction algorithm
Authors: Holmes Philip M. , O'Driscoll Shawn , Urban Matthew W.
Published: December 2020

Osteochondritis Dissecans (OCD) is a joint defect in which a crack in thesubchondral bone causes a separation of both subchondral bone and overlying cartilage from the bulk of the bone. Because there is an increased prevalence of OCD among youth athletes, an efficient, accurate, and non-ionizing screening method for this condition is being pursued. The aim of this project is to develop a clinical ultrasound image reconstruction algorithm that increases the detectability of bone surface defects, such as OCD. The proposed algorithm is a modified delay-multiply-and-sum (DMAS) algorithm that uses data acquired through synthetic aperture methods. The modifications made to the DMAS algorithm relevant to this work include transmit apodization and incoherent data summation. The modified DMAS algorithm was tested on data generated from k-Wave simulations and validated with experiments using bone mimicking material. Using both k-Wave and the bone mimicking material, we modeled fractures in the capitellum of the humerus with separations of 1, 2, and 3 mm. For experiments, we used synthetic aperture acquisitions using a Verasonics V1 system with a linear array (L7-4). The modified DMAS algorithm was found to enhance the clarity of bone surface defects when compared against DAS and DMAS algorithms.
Occult regions of suppressed coherence in ultrasonic liver images
Authors: Offerdahl Katelyn , Huber Matthew , Long James , Long Will , Bottenus Nick , Trahey Gregg
Published: December 2020

Lag-one coherence (LOC) estimates local levels of acoustic noise by measuring the spatial coherence between backscattered echo signals received by neighboring pairs of transducer elements. LOC can be directly related to signal to noise ratio (SNR) and contrast to noise ratio (CNR). We have acquired B-mode images and matched pixelwise LOC estimates in the livers of 10 healthy volunteers using a C5-2v probe on a Verasonics Vantage system and in Fullwave simulations with six abdominal walls over uniform speckle. We present evidence of temporally stable regions of suppressed LOC beneath the abdominal wall which recover to a stable asymptotic value at depth. Fullwave simulation results suggest that reverberation determines the initial amount of coherence suppression and aberration determines the asymptotic LOC value. The in vivo LOC values beneath the abdominal wall range from roughly 0.4 to 0.85, corresponding to SNRs of −3.5 dB to 15 dB, and the length of coherence suppression ranges from 0.5cm to 2.5 cm. These regions are occult; they present as temporally stable uniform liver on B-mode images. This is significant because clinicians will not be aware that lesions may be much more difficult to detect in this region, potentially leading to missed diagnoses.
Reduction of structural vibration and radiated noise using acoustic resistive volume
Authors: Liu Jin
Published: December 2020

Undesirable noise levels and shell vibrations from pipes and cavities with internal pulsating pressures is a common problem for HVAC, automobiles and airplanes. This study is concerned with providing effective noise control solutions without affecting overall system performance. Acoustic impedance optimization is carried out using a Fluid-Structure-Interaction FEA solver to reduce radiated noise by adjusting the acoustic impedance in the pipes and cavities to avoid excitation of internal acoustic modes. Porous materials with high porosity (>0.9) and with hole sizes much smaller than the viscous penetration depth are introduced inside the pipe and cavities to create resistance volumes to increase acoustic dissipation. In this way, acoustic traveling waves are promoted and the formation of standing waves is minimized. This in turn reduces surface vibration levels of the pipes thereby reducing radiated noise.
Multidomain modeling of moving coil speakers including multiple nonlinearities
Authors: Thompson Stephen C.
Published: December 2020

Accurate modeling of moving coil speakers must include nonlinearities in the magnetic force factor, mechanical mounting stiffness, and magnetic circuits. The same model must also include complicated linear effects such as eddy currents in the magnetic structure and thermoviscous losses in enclosures and small transmission paths. Including all of these in a single model is beyond the capability of conventional analog circuit models. Multidomain modeling with Simscape or Modelica offers a method of solution for all the features mentioned. A Simscape model with several nonlinearities will be demonstrated and compared with measurements from prototype speakers.
Forty-six years of learning, experiencing, and enjoying work with Larry Royster
Authors: Driscoll Dennis
Published: December 2020

It was late August 1973, on my first day as an undergraduate student, when I meet my academic advisor—Dr. Larry H. Royster. As I crammed 4 years of education into the next 5 years Larry was always there to provide counsel and guidance. Then I started grad school and it turned out he also had a research assistantship available to study occupational hearing loss. Two years later I completed my graduate program under Larry's direction. My professional career started in 1980 at Standard Oil Corporation of Indiana. Eight years later I decided to become a consultant in occupational noise, which I remain to this day. Throughout my career Larry continued to mentor me. We worked together on many different ventures from teaching professional development courses, working on machinery noise control, hearing loss litigation support, to co-authoring publications. My talk will describe many of these professional experiences. However, it is the personal relationship and fun I shared with Larry that I cherish the most, and I am pleased to share with you, too. To say Larry shaped my professional life is an understatement – overuse of hyperbole not withstanding meeting Larry was the turning point in my life.
Roysters and high fidelity hearing protection
Authors: Killion Mead
Published: December 2020

The Roysters' Chicago-Symphony-Orchestra study led to abandoning Plexiglass Barriers between the brass and viola sections: They reduced exposure by 3 dB in the viola section but increased it 3 dB for the bassoons. That study was also an important factor in the successful introduction by Etymotic Research of (a) 15 dB custom Musicians Earplugs (designed by ASA fellow Elmer Carlson), (b) inexpensive ready-fit ER20 20 dB HiFi earplugs (designed with Berger and Falco and Stewart), and (c) MusicPRO earplugs. About the latter, John Yeh, clarinetist with the CSO said: “These electronic earplugs allow me to hear everything, including the Maestro's instructions, while damping the onslaught of the brass band.” Nonetheless, there were frequent academic concerns about “not enough protection.” Indeed, E-A-R marketing initially declined to offer the 20 dB earplugs, and the Common Market outlawed low-attenuation earplugs and dictated that orchestras should not play above 85 dBA SPL. (I once measured a 106 dB SPL SLM peak at a balcony seat in Orchestra Hall!) These “not enough” complaints were wonderfully answered by Royster (1993): “Of the 1/3 of all factory workers who need protection, 76% need less than 10 dB.” He also observed that too much attenuation led to non-use.
Weakly nonlinear theory on a thermal effect inside bubble on plane pressure waves in bubbly water
Authors: Kamei Takafumi , Kanagawa Tetsuya , Ayukai Takahiro
Published: December 2020

Especially focusing on a thermal conduction and a thermodynamic process inside the bubble, we theoretically analyze weakly nonlinear propagation of plane progressive pressure waves in an initially quiescent water uniformly containing many spherical microbubbles. We utilize the famous model proposed by Prosperetti (1991) as the energy conservation equation. Some temperature gradient model such as Preston et al. (2002) and Sugiyama et al. (2005) are also used. For simplicity, the viscosity of gas phase and the phase change and mass transport across the bubble–liquid interface are omitted. We then derived the Korteweg–de Vries–Burgers (KdVB) equation including a correction term without differentiation due to the consideration of thermal conduction, from the basic equations for bubbly flows based on a mixture model. As a result, we clarified that the thermal effect contributes not only the dissipation effect but also the nonlinear effect. The coefficient of nonlinear term includes the ratio of specific heats of the ideal gas inside the bubble. We then concluded that the thermodynamic process inside bubble determines the wave propagation process.
Theoretical analysis on a nonlinear interaction of plane pressure waves with long and short wavelengths in bubbly water
Authors: Tanaka Katsunori , Kanagawa Tetsuya
Published: December 2020

Weakly nonlinear interaction between short and long waves in an quiescent water uniformly containing many spherical gas bubbles is theoretically investigated under the assumption of one-dimensional progressive pressure wave propagation. For simpicity, the bubbles do not coalesce, break up, disappear, and appear; thermal conduction and phase change are neglected. By the use of the singular perturbation analysis based on the method of multiple scales, we conduct the perturbation calculations up to the fifth order. We then derive the coupled equations the so-called SKdV type equations, from the set of governing equations for bubbly flows, one is the nonlinear Schrödinger (NLS) type equation for the short wave with a nonlinear interaction term and the other is the Korteweg–de Vries (KdV) type equation for the long wave with a nonlinear term of the short wave. Finally, some comments for waveforms will be presented from both viewpoints of analytical and numerical.
Enhanced acoustic transmission through an aqueous acoustic metasurface
Authors: Groopman Amber M. , Martin Theodore P. , Rohde Charles A. , Sieck Caleb F. , Guild Matthew D.
Published: December 2020

Acoustic metasurfaces are ultrathin (subwavelength thickness) structures that can demonstrate extreme acoustic properties, such as negative or near-zero values, similar to those seen in acoustic metamaterials. The negligibly small thickness of acoustic metasurfaces make them a more practical alternative to metamaterials for certain applications. In this work, we experimentally demonstrate an aqueous acoustic metamaterial that employs subwavelength, flexural elements that acoustically act in parallel to achieve enhanced acoustic transmission and broadband negative effective density. The metasurface was constructed from a brass plate, which was machined to have a parallel arrangement of circular, flexural elements on the surface, and experimentally tested in water over the nominal range of 50–100 kHz. The reflected and transmitted acoustic data were compared between a brass plate with and without the circular flexural elements. It was observed that the aqueous acoustic metasurface made from a brass plate with circular flexural elements showed improved broadband transmission. A detailed description of the experimental testing and analysis will be discussed. [Work supported by the Office of Naval Research]
Coupled-mode analysis of a nonreciprocal elastic wave circulator
Authors: Goldsberry Benjamin M. , Wallen Samuel P. , Haberman Michael R.
Published: December 2020

Acoustic and elastic metamaterials with time- and space-dependent material properties have received great attention recently as a means to increase the degree of control over mechanical waves. A circulator is a device that can transmit and receive signals in a nonreciprocal fashion using a network of ports attached to a junction having either spatiotemporally varying properties or momentum bias. The work presented here considers the numerical study of an elastic wave circulator, which is composed of three elastic waveguides attached to a thin elastic ring, creating a three-port network with 3-fold rotational symmetry. Nonreciprocity is achieved for both flexural and extensional waves by modulating the elastic modulus of the ring in a rotating fashion. An approximate model based on coupled-mode theory, which makes use of a plane wave basis, is derived and implemented. Steady state solutions are found, which include the generated harmonics of the modulation frequency. The coupled-mode model is compared with a finite element approach, and conditions on the system parameters that enable a high degree of nonreciprocity are then discussed in terms of a set of characteristic dimensionless numbers. [Work supported by NSF EFRI.]
Adaptation occurs following a single exposure to altered auditory feedback in speech
Authors: Hantzsch Lana , Parrell Benjamin , Niziolek Caroline A.
Published: December 2020

Auditory perturbations, or sensory errors caused by manipulating auditory feedback in near real-time, are known to induce instantaneous compensation as well as long-term adaptation responses in speech production. Adaptive responses are built through repetitive exposure to perturbations, but it is unknown how much learning occurs from a single exposure to an auditory perturbation. This trial-by-trial learning, known as one-shot learning, may provide insight into how individual events affect feed-forward control mechanisms and contribute to adaptation. One-shot learning is evident in reaching motor tasks, and the present study aims to understand its role in the speech sensorimotor system. Data were compiled from a set of studies which randomly exposed participants to isolated auditory perturbation events. On any given trial, the participants' first formant (F1) was either shifted up, shifted down, or remained unshifted while they pronounced a presented word. Data from unshifted trials that were preceded by a perturbation trial were extracted to examine if there was a learning effect that carried over from the previous, shifted trial. During unshifted trials that were preceded by a perturbation, participants adjusted their first formant in the opposite direction of the preceding shift, demonstrating that learning occurs even after a single auditory perturbation.
Developmental changes and effects of parental interaction on French-English bilingual infants' vocalization rates
Authors: Xu Katherine , Orena Adriel J. , Ruan Yufang , Polka Linda
Published: December 2020

In prior work, we investigated how several factors—social context (Social versus Non-Social & One versus Multiple speakers), speaker context (Mother versus Father), language (English versus French) and language dominance (Dominant versus Non-Dominant) – are related to vocalization rates in 10-month-olds growing up in English/French bilingual families (n = 21). This was accomplished by analyzing naturalistic daylong recordings obtained using the Language Environment Analysis (LENA) system. Here, we examined how these factors are related to vocalization rates in older infants by analyzing LENA recordings obtained when these same infants were 18 months of age (n = 16). Similar to previous findings, preliminary analysis showed a higher proportion of infant vocalizations occurred in social contexts (i.e., presence of adult speech). Moreover, more infant vocalizations occurred in contexts with one speaker as opposed to multiple speakers. In contrast to previous findings, 18-month-olds did not vocalize more when interacting with their mothers compared to their fathers. Infant vocalization rates were comparable in French and English input contexts. However, more infant vocalizations occurred in dominant language than in non-dominant language contexts. These findings will help us understand how parent-infant interactions change over time and shape the vocal behavioral of infants being raised in bilingual families.
Language input and volubility in French-English bilingual infants
Authors: Ruan Yufang , Orena Adriel J. , Xu Katherine , Polka Linda
Published: December 2020

Caregiver-child interaction is essential for language development. Previous research shows that the amount of one-on-one parentese experienced by monolingual infants predicts their concurrent vocalization (Ramírez-Esparza et al., 2014). Here we examined how language and social contexts are related to infant vocalization rates in French-English bilingual infants. Using the Language Environment Analysis (LENA) system, we collected daylong recordings from infants when they were 10- and 18-months of age (N = 21 and 16, respectively). LENA software provided estimations of infant vocalization and adult word counts in 30-second segments. We manually coded half of all segments for speaker context (who was speaking around the child), listener context (who the speech was directed towards), and language context (what language(s) was being used). Three main conclusions emerge from the analyses: (1) the more speech infants hear, the more they vocalize; (2) the input experienced in a one-on-one social context and in the dominant language has a strong relation with infant concurrent and projected volubility; (3) using both raw and proportional language measures to examine bilingual input is recommended. The findings inform our understanding of the relationship between language input and language development in bilingual infants.
Gradient effects and categorical perception co-exist
Authors: Sarkar Sreeparna , Hestvik Arild
Published: December 2020

Although the perception of speech sounds was originally thought to be purely categorical, subsequent behavioral studies have reported gradient perception. Recent intracranial studies and neuropsychological studies have also shown the existence of both categorical and gradient perception. The current study confirms this co-existence with a simple behavioral task where sensitivity to both within and between-category distinctions are tested within-subject. A VOT continuum of alveolar stops, 0 ms to 100 ms in 5 ms incremental steps of VOT was used to generate 840 pairs of sounds. Participants made a same/different decision for each pair. Results analyzed with Signal Detection Theory show sensitivity to phonetic gradience within-category, and sensitivity increased linearly with greater acoustic distance between the pairs. Interestingly, the linear increase was greater for /d/ than for /t/, which might be attributable to voiceless stops having a more open-ended VOT range. On the other hand, sensitivity to pairs from different categories was significantly greater (as expected), and here, d' did not change by the size of the VOT difference. In conclusion, we confirmed that even though listeners can detect within-category phonetic differences, phonological categorical perception co-exists with phonetic gradient perception.
Towards an understanding of tone category variability in Cantonese
Authors: Soo Rachel , Babel Molly
Published: December 2020

Cantonese is typically described as having 6 lexical tones. There are reports, however, of three mergers-in-progress; the contrasts between Tone (T) 2 and T5 [Baueret al., LVC 15(2), 211–225 (2003)], T3 and T6, and T4 and T6 [Moket al., LVC 25(3), 341–370 (2013)] are becoming neutralized. Previous work examined the perception of merging tone pairs on an 11-step continuum, in addition to non-merging control pairs (T2-T3 & T5-T6), finding more discrete categorization performance for non-merging than for merging tone pairs. In this study, we examine these same Cantonese tone pair continua with a goodness rating paradigm to understand category-internal structure. Listeners rated the goodness of items on a 7-point scale with real word landmarks as endpoints. Listeners generally rated items across the continua in merging pairs as more acceptable. Items from non-merging tone continua presented a more curious pattern, suggesting that listeners perceived the mid-points of continua as the best-sounding or worst-sounding items. In an attempt to understand these results and those of a previous categorization task, we explore acoustic-auditory similarity measures (e.g., dynamic time warping, Frechet distance, area between curves) between the tones, comparing these measures to listener behaviour.
Effects of filter cutoff on individual speaker identification
Authors: Boyd-Pratt Helen , Donai Jeremy
Published: December 2020

Two experiments were designed to determine the effects of high-and low-pass filtering on individual speaker identification in quiet and noise. Forty-four listeners ages 18i–35 years of age with normal hearing participated in the two experiments. Each experiment included listening to sentences under various filtered conditions and identifying the speaker. High-and low-pass filter cutoffs included 750, 1500, 2500, and 3500 Hz. Quiet: A significant main effect was found for speaker gender (F(1, 21) = 6.86, p < 0.05, ηp2 = 0.25), filter cutoff (F(3, 63) = 4.06, p < 0.05, ηp2 = 0.16), but not filter type (F(1, 21) = 4.00, p =0.058, ηp2 = 0.16), which approached statistical significance. Noise: A significant main effect was found for speaker gender (F(1, 21) = 19.24, p < 0.01, ηp2 = 0.48), filter type (F(1, 21) = 30.70, p < 0.01, ηp2 = 0.59, and filter cutoff (F(3, 63) = 6.82, p < 0.01, ηp2 = 0.25). These results suggest that even at the highest high-pass filter cutoffs (i.e., 2500 and 3500 Hz), listeners were capable of extracting information regarding speaker identity and that reducing access to higher-frequency information had a deleterious effect on identifying the speaker in quiet and noise.
Parametrically varying speech adapter length suggests two mechanisms for talker adaptation
Authors: Choi Ja Young , Kou Rita S. , Perrachione Tyler K.
Published: December 2020

Listeners are slower at processing mixed-talker speech than single-talker speech. This effect of talker variability is reduced when listeners can reorient their attention to each talker via auditory streaming. However, it remains unknown whether sufficient time for attentional reorientation can make speech processing in a mixed-talker context as efficient as processing single-talker speech. Here, we examined how speech processing efficiency for word identification changes with varying lengths of preceding speech. In single- and mixed-talker conditions, listeners identified target words in isolation or preceded by a carrier vowel (/⋀:/) of parametrically varying durations (300–1500 ms). Word identification was significantly slower in mixed-talker conditions versus single-talker conditions. The response time difference between the mixed- and single-talker conditions significantly decreased as the carrier duration increased from 0 to 600 ms, but carriers longer than 600 ms did not further reduce the additional processing costs in mixed-talker contexts. These results suggest two distinct mechanisms associated with speech processing efficiency: One for rapid adaptation up to 600ms, reflecting attentional orientation via auditory streaming; and another mechanism operating on longer timescales, perhaps reflecting cognitive resource allocation to accommodate the possibility of talker variability. Our ongoing work explores how these two processes operate over natural speech in mixed-talker contexts.
Vowel identification and goodness based on level of formant detail
Authors: Jibson Jonathan
Published: December 2020

Neel (2004) asked how much time-varying formant detail is needed for vowel identification. In that study, starting with vowel recordings from one male speaker and one female speaker, multiple stimuli were synthesized for each vowel: 1-point (monophthongal with midpoint values), 2-point (linear from onset to offset), 3-point, 5-point, and 11-point. Results suggested that a 3-point model was optimal. The present study partially replicates Neel (2004) but draws from more robust phonetic sources (Jacewicz et al., 2011; Hillenbrand et al., 1995). Eight English monophthongs were chosen for synthesis. 1-, 2-, 3-, and 5-point stimuli were created as described above, and another 1-point stimulus was created with onset values rather than midpoint values. These 40 stimuli were used in two studies (n = 18 for each). First was a vowel identification task, where the ten choices were [hVd] words with the chosen vowels (heed, hid, etc.). Second was a goodness rating task with a 7-point Likert scale, where participants were played a vowel stimulus while being shown the orthographic [hVd] word containing that vowel. The results of neither study showed improvements beyond 2-point stimuli, in contrast to the previous finding of 3-point stimuli as optimal.
Word-final palatalization and production planning in English
Authors: Dunagan Donald G. , Renwick Margaret E.
Published: December 2020

We analyze palatalization from /z/ to [3] at word boundaries in UK English. Previous research has investigated palatalization in the context of /s#j/, showing that lexical frequency influences its occurrence across word boundaries. Palatalization by voiced coronal fricatives is less well-understood, particularly in naturalistic speech, which we study using the Audio BNC (http://www.phon.ox.ac.uk/AudioBNC). We hypothesize that palatalization across word boundaries is subject to the Production Planning Hypothesis. That is, palatalization should be modulated by the extent to which phonological information for the second word is available when the first word is planned. We analyze spectral center of gravity (CoG) in fricatives from 7,134 word pairs across four phonological contexts, comparing test tokens subject to palatalization, /z#j/ (e.g., “is you”), to control pairs containing non-alternating /z#V/ (e.g., “is it”), or /Ê’/ (e.g., “rouge it,” “precision”). Although significant correlates of CoG vary by speaker gender, the acoustics of /z#j/ are predicted by factors related to production planning, including fricative duration, speech rate, presence and length of inter-word pause or sentence boundary, word-pair frequency, and following vowel acoustics. A supervised classification task using acoustics and lexical frequency metrics also distinguishes /z#j/ from /z#V/ and /3#V/ with above-chance accuracy, illustrating automatic detection of palatalization.
Brain-to-brain synchrony in assessing listening effort
Authors: Green Geoff D. , Jacewicz Ewa , Arzbecker Lian J. , Santosa Hendrik , Fox Robert A.
Published: December 2020

Evidence from the neuroscience of verbal communication shows that when two people share information (one speaks and the other listens) their brain activities work in synchrony (Silbert et al., 2014). This brain-to-brain synchrony (B-Bsync) is lost when the listener fails to understand the speaker's message. We test the hypothesis that B-Bsync predicts the level of effort involved in auditory processing: strong neural brain-to-brain coupling reflects relatively effortless processing; conversely, the weaker the coupling, the greater the effort, and the worse the processing and comprehension. We propose that B-Bsync affords a more sensitive assessment of listening effort than currently available on the basis of behavioral measures. Using functional near-infrared spectroscopy (fNIRS) and fNIRS-based hyperscanning approach, we analyze patterns of neural activity separately in the speaker and in the listener, and assess statistically the correspondence in their brain activation (the degree of synchronized activation of cortical sites and temporal symmetry). We examine the effects of degraded source (i.e., accented American English in speakers telling several short stories) on B-Bsync, predicting the strongest coupling and the shortest time delay when the accent of the listener matches that of the speaker, followed by regional dialect mismatch and foreign-accent mismatch, respectively.
Auditory stream discontinuities interfere with speech processing efficiency
Authors: Lim Sung-Joo , Shinn-Cunningham Barbara , Perrachione Tyler K.
Published: December 2020

Listeners process speech from mixed talkers less efficiently than from one continuous talker. An auditory streaming framework may help explain this effect: talker discontinuity may disrupt listeners' attentional focus, decreasing speech processing efficiency. In two experiments, we examined how auditory interruption of a speech stream interfered with speech processing. In experiment 1, we sporadically presented non-speech distractors (e.g., text message alerts) while listeners identified words spoken by either one consistent talker or multiple talkers. Word identification was slower immediately following non-speech distractors, and this disruption was greater when listening to speech from a single talker than mixed talkers. Experiment 2 tested the impact of interruptions caused by non-speech distractors or sudden switches to a different talker while listeners identified words spoken by a single, consistent talker. Listeners were slower at responding to non-speech distractors than a new talker's speech, but across interruption types, the magnitude of recovery relative to the magnitude of interruption was similar. These results suggest that both speech and non-speech discontinuities interfere with speech processing by disrupting listeners' attentional focus toa talker. Moreover, interruptions appear less disruptive when listeners pre-deployed cognitive resources to accommodate expected discontinuities, such as when listening to mixed-talker speech.
Neural-behavioral relation in phonetic discrimination modulated by language background
Authors: Zhao Tian , Kuhl Patricia K.
Published: December 2020

It is well demonstrated that sensitivities to small acoustic differences in speech contrasts are heavily influenced by the listeners' language background. At the behavioral level, listeners have been shown to discriminate native speech contrasts better than non-native speech contrasts. At the cortical level, mismatch response have been shown to index neural sensitivities to speech contrasts. Using EEG, researchers have observed larger mismatch negativity for native contrasts compared to nonnative contrasts. Using MEG, researchers have described a more focused and efficient neural processing pattern for native contrasts than nonnative contrasts. However, the relation between behavioral discrimination and neural responses are rarely reported. In the current study, 15 native English speakers and 15 native Spanish speakers completed both a behavioral discrimination task and a separate MEG recording using an oddball paradigm. The speech sounds differed on the voice-onset-time (i.e., prevoiced /ba/ with −40 ms VOT versus voiced /ba/ with + 10 ms VOT), representing a phonetic contrast only in Spanish. At the group level, English speakers exhibited significantly lower behavioral sensitivity (d') to the contrast and less focused and efficient MEG mismatch responses, replicating previous studies. At the individual level, a significant relation between behavioral sensitivity and the mismatch response only exists in the Spanish group, suggesting potential differences in the mechanisms driving the discrimination for the two groups.
How do blind people use semantic and phonological cues for spoken word recognition? An ERP study
Authors: Feng Jie , Liu Chang , Li Yalan , Sun Peng , Xie Ruibo , Zhao Ying , Chen Hongjun , Wu Xinchun
Published: December 2020

Spoken word recognition is affected by phonemic and semantic details of speech at pre-lexical and lexical levels. The current study examined how blind people used semantic and phonological cues for spoken word recognition. Thirty blind and twenty-nine age-matched sighted people participated in this study. We manipulated the semantic similarity and phonological similarity between the primes and targets in three experimental conditions: semantic-related with different phonology (S + P-), semantic-unrelated with different phonology (S-P-), and semantic-unrelated with the same phonology (S-P + ). Results showed that blind participants had higher accuracies than sighted individuals in both the S-P- and S-P + conditions. As both groups exhibited larger N400 amplitude in the S-P- versus S + P- conditions, the semantic-unrelated N400 effect was stronger in blind than in sighted participants, suggesting a more sensitive processing of semantic information in blind people. Moreover, sighted participants showed stronger N400 effect in the S-P + than in the S-P- conditions, but blind participants did not, indicating an interference of phonological similarity in spoken word recognition for sighted listeners only. In summary, blind people are more sensitive to semantic cues and less susceptible to phonological similarity interference during spoken word recognition than sighted people.
Versatile system analysis procedure based on a frequency domain variant of velvet noise
Authors: Kawahara Hideki , Sakakibara Ken-Ichi , Mizumachi Mitsunori , Morise Masanori , Banno Hideki
Published: December 2020

We introduce a method that enables the simultaneous measurement of system attributes. The attributes are the linear time-invariant, nonlinear time-invariant, and random and extra responses without introducing additional equipment and post-processing. This new procedure uses a new member of time stretched pulses called FVN (Frequency domain variant of Velvet Noise). A high degree of design freedom makes individual FVN generated using different random number seeds plays the key for making orthogonal sequences. We made this procedure and an interactive and realtime acoustic measurement tool in an open-source repository. This procedure and tool enable in-depth measurement of acoustic systems in everyday conditions. The proposed procedure is general and applies to many fields such as altered auditory feedback experiments and assessment of recording and coding effects on voice research.
A new test standard for measuring impact noise in buildings
Authors: Lilly Jerry G.
Published: December 2020

In 2018, ASTM International published a new laboratory test standard for measuring impact noise in buildings. Unlike previous ASTM standards for impact noise, which assess impact noise transmission into nearyby spaces, this test method evaluates impact sound radiating into the source room. This presentation will review the history of the development of this standard, discuss limitations of the current standard, and suggest improvements that are being considered.
Correlation methods of room impulse responses for chamber-based sound insulation measurements
Authors: Xiang Ning
Published: December 2020

Sound insulation of building elements, such as walls, doors and windows are quantified in standardized test chambers (ISO 10140, 2010; ASTM E90-09, 2016). Standardized test methods employ continuous noise signals to excite the sending room. The sound insulation is determined through averaged sound level differences between the sending and receiving rooms with a correction term taking into account absorption in the receiving room. High insulation elements often post challenges for reliable measurement results since insufficient signal-to-noise ratios in the receiving room make the measurement inaccurate, often invalid. This paper discusses advantages of measurement techniques using pseudo random noise and /or log-sweep sine signals followed by efficient cross-correlation processing, leading to room impulse responses. Energy building of room impulse responses measured at microphone positions in both rooms also yields spatially averaged differences of sound energy levels. In addition, the room impulse responses measured in the receiving rooms also provide reverberation times to evaluate overall room absorption. Due to cross-correlation, the room impulse responses even in low signal-to-noise situations can be measured with drastically improved quality, yielding more reliable evaluation of level differences. This paper highlights theoretic fundamentals of correlation methods, their equivalence, and differences with the classical noise excitation method.
Updated comparison of different resilient channels with and without isolators
Authors: Gernhart Elzo F.
Published: December 2020

It is the purpose of this presentation to provide a current update of the major resilient channels available with and without acoustical isolators in floor-ceiling assemblies with and without various finished floor systems. All the testing was conducted with in twelve months of the date of this paper. All the samples where either purchased at retail outlets or donated by the manufacturers for these tests. Here in we compare the most popular brand names and models of resilient channels with and without resilient channel isolators. The finished flooring and finished flooring mats where standardized to reduce the number of finished flooring tests required to demonstrate the advantages of the resilient channels and the resilient isolator. All though this presentation may not include 100% every available product. We have selected the most commonly used products: resilient channels, rubber mat and finished flooring. In open web timber truss, TJI and solid timber joist. This research should be important to every acoustical engineer whom is concerned about delivering current state of the art, cost effective, noise control solutions to the client.
Peter Narins: From laboratory to field and back again
Authors: Gerhardt H C.
Published: December 2020

Scientists trained as engineers rarely venture into the natural world to study the behavior of animals whose auditory systems they analyze in the laboratory. But Peter Narins began his career as a graduate student studying the behavior of the co-qui frog in Puerto Rico; his goal was to learn the biological significance of the two notes of the calls of this species, whose peripheral auditory system he was studying in Bob Capranica's laboratory at Cornell. He found that the two different inner ear organs – typical of anuran amphibians – were tuned to different frequencies corresponding to those of the two notes and that these notes played different roles in the communication system of this species. Peter continued to delve deeper into the auditory system of this and other frogs, making significant discoveries about traveling waves, two-tone inhibition, otoacoustic emissions, and phase-locking. These discoveries were then related to further behavioral analyses of acoustic pattern recognition and sound localization, which is based on a pressure-difference system. Finally, Peter's field work has included studies of exotic species that produce complex signals, ultrasonic signals, which are audible to them, and sensory systems underlying seismic communication.
Unusual phenomena in sound communication and hearing in anuran amphibians
Authors: Feng Albert S.
Published: December 2020

The ability of anuran amphibians to detect, recognize and localize sound is important for their reproductive success, mate choice and competitive interactions between calling males. Recent studies have revealed that the view of frogs possessing only a crude perceptual ability is overly simplistic, or wrong altogether. Whereas the evidence of the antithesis is broad, only some of the evidence will be highlighted here due to space limitation. (1) Two species of torrent frogs that inhabit noisy streams characterized by intense but predominantly low-frequency stream noise have been shown to have evolved the ability to hear and communicate with ultrasound. (2) Despite the small body size and short interaural distance of male Odorrana tomorta, these animals can localize sound with an acuity that rivals those of barn owls, dolphins and humans. (3) These same animals uniquely possess (among the vertebrates) the ability to actively control the frequency sensitivity of hearing. (4) The vocal signals of these animals show huge intra- and interindividual variability, and despite this they show the ability to discriminate neighbors' and strangers' calls. Although we have some insights into the mechanisms underlying these unusual hearing abilities much work remains to be done for gaining a comprehensive understanding.
Improved characterization of ultrasound sources by radiation force balance using acoustic holography in place of plane-wave and geometric approximations
Authors: Sapozhnikov Oleg A. , Nikolaev Dmitry A. , Tsysar Sergey A. , Khokhlova Vera A. , Kreider Wayne
Published: December 2020

The radiation force balance (RFB) method is a widely accepted approach to characterize ultrasound sources used both in therapy and imaging. Measurement of the radiation force F acting on an absorbing or reflecting target provides the acoustic power W. The RFB method is based on the linear relationship W = Y · c · F, where c is the speed of sound in the propagation medium and Y is a dimensionless coefficient that depends on the wave structure and reflective properties of the target. The widely accepted expression for a plane wave and an ideal absorber is Y = 1. For a spherically focused source the geometric approximation factor Y = 2/(1 + cos α) is used, where α is the half-aperture angle. The exactness of these and similar approximate relations cannot be checked experimentally because no real sources emit such idealized waves. In the current talk, a more precise approach is presented to determine Y for a given source. To account for the spatial field structure, the acoustic holography method was employed using a 2-D scan with a calibrated hydrophone. In this way, the ultrasound beam's explicitly measured angular spectrum can be used to relate radiation force and acoustic power. [Work supported by NIH R01EB025187 and R01EB007643, and RSF 19-12-00148.]