bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance analysis of various fundamental frequency estimation algorithms in the context of pathological speech
Authors: Vaysse Robin , Astésano Corine , Farinas Jérôme
Published: November 2022

Reliable fundamental frequency (f0) extraction algorithms are crucial in many fields of speech research. The current bulk of studies testing the robustness of different algorithms have focused on healthy speech and/or measurements of sustained vowels. Few studies have tested f0 estimations in the context of pathological speech, and even fewer on continuous speech. The present study evaluated 12 available pitch detection algorithms on a corpus of read speech by 24 speakers (8 healthy speakers, 8 speakers with Parkinson's disease, and 8 with head and neck cancer). Two fusion methods' algorithms have been tested: one based on the median of algorithms and one based on the fusion between the best algorithm for voicing detection and the algorithm that generates the most accurate f0 estimations on voiced parts. Our results show that time-domain algorithms, like REAPER, are best for voicing detection while deep neural network algorithms, like FCN- f0, yield better accuracy for the f0 values on voiced parts. The combination of REAPER and FCN- f0 yields the best ratio performance/implementation complexity, since it generates less than 4% errors on voicing detection and less than 5% of gross errors in the estimation of the f0 values for all speaker groups.
Introduction to the special issue on education in acoustics
Authors: Russell Daniel A. , Wilson Preston S.
Published: November 2022

A substantial fraction of the membership of the Acoustical Society of America are faculty at various types of educational institutions and are actively engaged in educational activities. However, papers focusing on aspects of teaching, pedagogy, demonstrations, student learning, and other education topics are not often published in JASA, even though the Education in Acoustics Committee regularly offers special sessions on these topics at every ASA meeting. This special issue of JASA dedicated to Education in Acoustics includes 41 papers from authors all over the world. This introduction to the special issue briefly describes each of the papers, which have been organized into several broad categories: teaching methods and exercises; project-based learning; use of experiments, demos, and experiential learning; adapting to teaching during COVID-19; circuit models and impedance concepts; software apps and online resources; teaching musical acoustics; and descriptions of acoustics programs at a variety of institutions.
The effects of interaural correlation and interaural place of stimulation asymmetry on binaural fusion
Authors: Aronoff Justin M. , Soleimanifar Simin , BK Prajna , Jawad Mona , Bernstein Leslie R.
Published: November 2022

The combination of information at the two ears resulting in the perception of a singular auditory percept is referred to as binaural fusion. The stimulation received by bilateral cochlear implant (CI) users sometimes fails to foster binaural fusion. The goal of this study was to assess, for CI users, the extents to and manners in which interaural correlation of stimulation and the degree of interaural place of stimulation asymmetry affect binaural fusion. Bilateral CI users were presented with 1000 Hz pulse trains modulated by envelopes for which the interaural correlation was manipulated. Additionally, one electrode from one ear was paired with different electrodes from the other ear in order to manipulate interaural asymmetry. Listeners indicated the spatial diffuseness of the sound they perceived and whether they perceived a unitary auditory “image” by rotating a dial to manipulate a visual representation of their perception superimposed on a picture of a human head. Additionally, listeners could move the lateral position of the visual representations left or right, indicating perceived laterality. The results suggest that, independent of the degree of interaural asymmetry, the interaural correlation of the envelope was related directly to the degree of perceived binaural fusion.
Toward predicting Arctic Ocean acoustic travel times using an Earth system model
Authors: Niklasson Siobhan , Veneziani Milena , Rowe Charlotte , Bilek Susan , Price Stephen , Roberts Andrew , Worcester Peter F. , Dzieciuch Matthew
Published: November 2022

The hydroacoustic environment of a rapidly warming Arctic Ocean will be impacted by changing thermohaline structure, increased marine traffic, changes in sea ice coverage, and likely increases in microseism/storm noise. This will lead to obsolescence for today’s Arctic Ocean acoustic models just as the need for understanding and monitoring the Arctic acoustic environment becomes more critical. To make sophisticated predictions for coming conditions, we need fully-coupled Earth system models. Los Alamos National Laboratory is contributing to developing the Department of Energy’s Energy Exascale Earth System Model (E3SM), which can potentially predict the ocean and sea ice conditions necessary to drive an acoustics model in a rapidly-evolving Arctic Ocean. We present a preliminary analysis of a comparison of acoustic travel times in the Canada Basin calculated from E3SM simulations with measured travel times from the 2016–2017 Canada Basin Acoustic Propagation Experiment (CANAPE) and travel times computed from ice-tethered-profiler measurements of acoustic properties in the water column. The goals of this effort are to provide boundary ocean conditions to an acoustic model, to quantify the ocean acoustic implications of climate change, as well as to create a climate-aware atlas of global acoustic noise that could be applied, for example, in signal detection.
Low cost and low energy 3D volumetric histotripsy using nanodroplet vaporization
Authors: Glickstein Bar , Ilovitsh Tali
Published: November 2022

Low pressure histotripsy may facilitate current treatments that require extremely high pressures. Here, a new technology platform for low-cost and low-energy 3D volumetric ultrasound histotripsy using nanodroplets was developed. The two-step approach involves the vaporization of the nanodroplets into gaseous microbubbles via a 1D rotating imaging probe (center frequency of 3.5 MHz). This transducer is situated within a therapeutic transducer that operates at a center frequency of 105 kHz. The therapeutic transducer is used to implode the vaporized nanodroplets and trigger potent mechanical effects in the surrounding tissues. Rotating the imaging transducer creates a circular vaporized ND shape, that upon their implosion generates a round shape lesion. In comparison, an elongated lesion shape is formed when using a standard 1D imaging transducer for ND activation. Initial optimization experiments were performed in tissue-mimicking phantoms, and ex-vivo chicken liver samples. Next, nanodroplet-mediated histotripsy was tested in a breast cancer tumor model in mice. The results confirm the generation of significant lesions and tumor tissue debulking compared to all control groups. Our approach facilitate the creation of large volume mechanical damage in tissues and solid tumors.
Exploration of nonideal effects in a beam model of a fuzzy structure
Authors: Ginsberg Jerry H.
Published: November 2022

The presentation that preceded this one analyzed a model of a fuzzy structure as a beam with multiple suspended SDOFs. It examined the degree to which phenomena encountered in a model of the master as a rigid body are replicated when the base displacements of the attachments are unequal. The conclusion was that many response features are replicated in the frequency domain, whereas contributions of higher structure modes cause time domain responses to differ. The present paper examines whether the numerous idealizations that led to that conclusion are crucial. Parameters that are examined are tuning and bandwidth of the fixed base SDOF frequencies, and randomness of the spectral and spatial distribution of the fixed base SDOF natural frequencies. Responses extracted from an “exact” state space solution of the equations of motion show that minor randomness can significantly alter, and sometimes obscure, the phenomena observed in the ideal case. The results bring to the fore the question of whether phenomena observed in idealized fuzzy models are relevant to actual structures.
The effect of contracting COVID on speech perception in high-school students: Evidence from the brain
Authors: Karani Shaun , Yu Yan H.
Published: November 2022

Accumulating evidence suggest that some individuals who recovered from COVID experience “brain fog” aside from other organ dysfunctions. Many young individuals who contracted with COVID have relatively mild symptoms and rapid recovery. However, it is unknow whether COVID have any negative impact on their brain function. The current study compared the neural response to speech sounds in high-schooler with and without a history of contracting COVID. An event-related potential paradigm was used, and the electro-encephalogram (EEG) waves were timelocked to each speech stimulus. The mismatch negativity responses (the different between the standard and deviant sounds) were compared between the two participant groups. Preliminary analysis suggested that there are some differences between the experiment group and the control group. Further studies need to examine the long-term effect of COVID on brain and cognitive function in the young population.
Repeat and rephrase: Assessing implementation of communication strategies in speakers with Parkinson's disease
Authors: Fletcher Annalise , Nalley Brian , Budge Samantha , Wisler Alan
Published: November 2022

When encountering challenging communicative situations, speakers with dysarthria are commonly advised to rephrase their sentences, avoiding jargon and using predictable words. However, there are no standard protocols for assessing this skill. The current study explores a short educational protocol focused on rephrasing complex sentences. There are two primary research questions: 1) what (if any) acoustic and lexical changes occur when speakers are prompted to rephrase sentences, and 2) can speakers with dysarthria increase their intelligibility when repeating or rephrasing a message? Speech samples were collected from eleven speakers with Parkinson’s disease. In a baseline condition, speakers read 29 sentences from the Natural Stories Corpus. Following this, speakers received verbal instructions on how to rephrase statements. In the rephrased condition, speakers were given the same stimuli and prompted to repeat the story using different words if desired. Preliminary results revealed statistically significant reductions in lexical diversity following the education protocol. Mean-segmented type-to-token (MSTTR) ratio was 7.57% lower in the rephrased condition, a difference which was significant at the p = 0.001 level. Although differences varied across participants, none showed increases from the original passage. Evaluations of speaking rate and intelligibility in the baseline and rephrased conditions will also be presented.
Using a spectral entropy criterion for improved onset picking in ultrasonic testing
Authors: Bühling Benjamin , Maack Stefan
Published: November 2022

In ultrasonic testing, the time of flight (ToF) of a signal can be used to infer material and structural properties of a test item. In dispersive media, extracting the bulk wave velocity from a received signal is challenging as the waveform changes along its path of propagation. When using signal features such as the first peak or the envelope maximum, the calculated velocity changes with the propagation distance. This does not occur when picking the signal onset. Borrowing from seismology, researchers used the Akaike information criterion (AIC) picker to automatically obtain onset times. In addition to being dependent on arbitrarily set parameters, the AIC picker assumes no prior knowledge of the spectral properties of the signal. This is unnecessary in ultrasonic through-transmission testing, where the signal spectrum is known to differ significantly from noise. In this contribution, a novel parameter-free onset picker is proposed, that is based on a spectral entropy criterion (SEC) to model the signal using the AIC framework. Synthetic and experimental data are used to compare the performance of SEC and AIC pickers, showing an improved accuracy for densely sampled data.
Improving the robustness of spectral estimation to loud transients with a truncated order statistics filter
Authors: Anchieta David C. , Buck John R.
Published: November 2022

Underwater acoustic recordings often include loud transients from human or natural sources. The transients cause a positive bias for Welch's average periodogram spectral estimator when estimating the power spectral density of the background environment. Estimators based on single order statistics (e.g., the sample median) avoid the bias caused by outliers at the cost of a higher variance than the sample mean. Schwock and Abadi (2021) showed that, for exponential random variables, the estimator based on the 80th sample percentile has the lowest variance among any unbiased estimator based on a single order statistics. This work tests a hybrid approach between Welch's and order statistics estimators by performing a weighted sum of the quietest subset of ordered samples of the periodograms. By discarding the loudest samples of the periodogram, the truncated linear order statistics filter (TLOSF) reduces the bias caused by loud transients. By combining multiple order statistics into the estimate, the TLOSF achieves a lower variance than the 80th percentile estimator. The TLOSF reduced the MSE by 1dB compared to Schwock & Abadi's 80th percentile estimator for a mixture combining an exponential distribution with 1% outliers 23 dB above the background. On periodograms of shallow water hydrophone recordings, the TLOSF yielded a lower output power in the frequency bins where both the Welch's and 80th percentile estimators had a positive bias due to loud transients. [Work supported by ONR Code 321US.]
Measuring ocean mixing: From observing processes to quantifying impacts
Authors: Whalen Caitlin
Published: November 2022

The impacts of ocean mixing are varied, ranging from the local across-isopycnal transport of heat, salt, and nutrients, to the global overturning circulation with implications for climate. A full understanding of turbulent mixing, from driving processes to impacts, spans all oceanic time and length scales. Turbulent mixing in the ocean occur on scales less than centimeters and timescales less than hours, yet the processes that drive this turbulence occurs on meters to 100s of km length scales and the impact of the turbulent mixing spans the full range of oceanic spatiotemporal scales. Here, we will discuss current approaches to measuring ocean mixing and explore how to bridge this scale gap to link the turbulence measurements to the processes that drive ocean mixing and the subsequent impacts. Intriguing examples of ocean mixing processes and their influence on ocean dynamics will be discussed throughout.
Acoustic tomography measurement and large-eddy simulation of macroturbulence in high flow tidal channels
Authors: Hay Alex E. , Zedel Len , Creech Angus , Razaz Mahdi , Kawanisi Kiyosi
Published: November 2022

Velocity spectra from a pilot tomography experiment in Grand Passage, Nova Scotia, exhibit the structure at 10 m to several 100 m scales similar to that of the spectra of vertically integrated velocity registered by bottom-mounted acoustic Doppler profilers. The experiment was motivated in part by the need for flow and turbulence measurement at sites being targeted for in-stream tidal power development, and by the potential of acoustic tomography for providing this information from shore-based locations in near real time. The measurements were made using a single pair of acoustic transceivers operating at 7 kHz and separated by 1.5 km at an oblique angle to the channel axis. Limited to a single cross-channel path, the experiment provided no information on the spatial structure of the turbulence. In order to investigate this structure, virtual tomographic experiments were carried out by propagating pulses through with meter-scale resolution velocity fields from a non-hydrostatic large-eddy simulation (LES) model of flow in Grand Passage. Results from these virtual experiments are presented, and their implications are discussed in relation to the potential of multi-transceiver tomography for macro-turbulence measurement and the role of horizontal shear in macro-turbulence production in coastal environments.
Sensing of ocean mixing via forward scattering acoustic scintillation
Authors: Colosi John A. , Duda Timothy F.
Published: November 2022

Ocean mixing process observations show complex spatio-temporal patterns as well as energy and dissipation levels that vary over six or more orders of magnitude, creating a challenging sampling problem. Acoustic imaging of ocean turbulent structures is informative, but extraction of quantities like spectra and dissipation rates of kinetic energy, ε, and temperature variance, Χ, requires geometric sampling constraints. Here, a remote sensing approach is proposed in the spirit of Di Iorio and Farmer (1994), and Duda et al. (1988), based on weak multiple-forward scattering physics. In the correct scattering regime, observations of the wavenumber spectrum of acoustic intensity obtained on a vertical array gives a direct measure of the range average turbulence index of the refraction spectrum in a plane transverse to the acoustic path. In this talk, the theory will be reviewed and some illustrative simulations will be presented; importantly, one-way acoustic transmission measures a combination of both ε and Χ. Experimental arrangements (frequency/range) where the theory is expected to apply will be outlined with an eye towards observing bottom boundary layer mixing. With a suitable vertical array, one could resolve scales from the smallest internal waves (∼several meters), through the transition regime, and down to scales of turbulence (∼tens of cm).
Acoustic backscatter from bubbles as a (quasi)passive tracer of turbulent mixing in high-flow tidal channels
Authors: Guerra Maricarmen , Hay Alex E.
Published: November 2022

In high-flow tidal channels, the water column tends to be well-mixed vertically due to the high levels of turbulence. Under favorable circumstances, such as those in which wind waves incident at the channel entrance from the adjoining open ocean or large embayment are opposed by the tidal flow, the waves steepen and break as they propagate upstream, resulting in bubble injection at the sea surface. These bubbles are then mixed downward by the tidally generated turbulence, resulting in pronounced, surface-connected, downward-propagating plumes of high backscatter in records from bottom-mounted upward-looking acoustic Doppler current profilers, typically operating at 100s of kHz. Letting the backscatter amplitude represent a pseudo-concentration, C, we demonstrate that the vertical turbulent diffusivity, K, can be estimated from the vertical turbulent flux i < c′w′> along the axis of the vertical beam, and the mean vertical gradient, dC/dz. Intriguingly, and despite the fact that bubbles are positively buoyant, the resulting estimates of K are very close to the values of momentum diffusivity required to obtain good agreement between the observed tidal velocities and a data-validated numerical tidal circulation model for the particular channel in question
Ultrasound-guided microbubble-mediated brain therapy with a modular transmit/receive phased array
Authors: Jones Ryan M. , McMahon Dallan , Leavitt Dallas , Ramdoyal Rohan , Lee Kang , Kan Wai Meng , Yang Steven , Chen Yi-Shiuan , Hynynen Kullervo
Published: November 2022

The development of low-cost, ultrasound-guided focused ultrasound (USgFUS) treatment platforms is expected to advance the adoption of microbubble (MB)-mediated brain therapy by improving access to the technology. Our group has designed and fabricated clinical-scale transmit/receive phased array systems for MB-mediated USgFUS brain therapy. Acoustic field simulations were carried out to optimize array element placement, and transducer scaffolds were constructed using 3D printing techniques. These devices have been employed for skull computed tomography-array registration, 3D spatial mapping of MB activity in vivo through ex-vivo human skullcaps via noninvasive aberration correction methods, and we have harnessed this spatiotemporal cavitation information to calibrate exposure levels for safe volumetric blood-brain barrier opening. At higher exposure levels, we have demonstrated the ability of 3D MB imaging data to predict the tissue damage volume distributions induced during nonthermal brain ablation. Ultrafast processing of acoustic emissions data has been shown to uncover MB dynamics hidden by conventional whole-burst temporal averaging, and can inform temporal undersampling strategies when millisecond-long tone bursts are applied. Machine learning approaches can assist with image-based classification of MB activity, which may result in finer control of the induced bioeffects. This talk will focus on our recent results obtained with a novel modular USgFUS phased array system.
Generating patient-specific acoustic simulations for transcranial focused ultrasound procedures based on optical tracking information
Authors: Sigona Michelle K. , Manuel Thomas J. , Luo Huiwen , Phipps Marshal A. , Yang Pai-Feng , Boroujeni Kianoush Banaie , Treuting Robert L. , Womelsdorf Thilo , Newton Allen , Grissom Will , Chen Li Min , Caskey Charles F.
Published: November 2022

During transcranial focused ultrasound (FUS) procedures, accurate targeting is important and neuronavigation with optically tracked tools is used to estimate the free-field focal location on pre-acquired images. Offline neuronavigation systems do not typically incorporate aberrating effects of the skull known to displace and distort the focus. Here, we developed a pipeline that integrated patient-specific acoustic simulations informed by transformations from optically tracked FUS procedures as a tool to evaluate transcranial pressure fields and demonstrated its use in three FUS scenarios: magnetic resonance imaging-guided (MR-guided) phantom experiments, MR-guided non-human primate (NHP) experiments, an offline behaving NHP experiments. Distance vectors between the estimated focus from optical tracking and peak intracranial location from simulations were less than 1 mm for all groups (Phantom: 0.6 ± 0.3 mm, NHP: 0.7 ± 0.3 mm, Behaving NHP: 0.5 ± 0.2 mm). Comparisons of the target registration error of MR measurements with the optically tracked focus (TRETracked) and simulated focus (TRESimulated) suggest that focal location errors are dominated by optical tracking errors rather than aberration through the skull in the NHP (Phantom: TRETracked: 3.3 ± 1.4 mm, Phantom TRESimulated: 3.3 ± 1.9 mm, NHP TRETracked: 3.9 ± 1.9 mm, NHP TRESimulated: 4.1 ± 1.6 mm). Our software pipeline provides patient-specific estimates of the acoustic field during transcranial FUS procedures.
Inclusion of environmental stochasticity in navy system performance modeling
Authors: Heaney Kevin D. , Coelho Emanuel F.
Published: November 2022

The performance of all acoustic navy systems is criticallly dependent upon the environmental conditions for propagation, primarily the ocean sound speed structure, the seafloor topography, the sediment type and the sea surface characteristics. Advances in computational power and improvements in hydrodynamic modeling have led to the opportunity of including ocean varaibiltiy and uncertainty into the acoustic propagation portion of system performance and, therefore, through the application of straight forward statistics into the performance prediction product. The first application of stochastic processing is in the computation of ambient noise (the shipping and noise sounsdcape) for comparison between modeled noise and measurements from long-term buoy deployments. Uncertainty in ship source level, position, wind speed, and environmental variabiility is key drivers in the model-data comparison. A second example of inclusion of environmental stochasticity in the passive anti-submarine warfare scenario of a passive surveillance barrier. A primary challenge here is in the communication of the uncertainty to a community that is used to thinking in simple performance metrics, such as range of the day. The last example is the use of an ensemble ocean forecast in the computation of the spread in eigenray arrivals for a real-time tomography system utilizing an active ASW sonobuoy field.
Acoustic treatments for indoor and outdoor firing ranges
Authors: Bergiadis Willaim L.
Published: November 2022

Small-caliber firearms can produce impulse noises that frequently exceed 150 dB peak sound pressure level (dB pSPL) and can approach 185 dB pSPL. These impulse noises can present a significant risk for noise-induced hearing loss for the unprotected ear and pose a risk for persons wearing hearing protection that is possibly poorly fitted or insufficient. For range safety officers and personnel who work in the firing range on a regular basis, the daily cumulative effects of noise exposure can lead to increased fatigue and stress. Acoustic treatments of the reflective surfaces can mitigate these health risks. This paper will review some community noise guidelines as well as health and safety regulations. As a manufacturer of acoustic range treatments, the Troy System materials will be reviewed with regards to their laboratory performance and their capabilities to reduce noise in various firing ranges. One aspect of performance that may be overlooked is the safety features of the materials which Troy Acoustics provides, such as flammability, ability to be cleaned, and the resistance to moisture and mold.
Measuring impulse insertion loss of hearing protection device using high-level impulse noise
Authors: Murphy William J. , Flamme Gregory , Tasko Stephen M. , Deiters Kristy K. , Finan Donald S. , Meinke Deanna K. , Lankford James E. , Stewart Michael
Published: November 2022

The American National Standard, ANSI S12.42-2010, specifies the impulse peak insertion loss (IPIL) for a hearing protection device (HPD) using an acoustic test fixture (ATF) over a range of impulse levels nominally at 132, 150, and 168 dB peak sound pressure level (dB pSPL). The GRAS 45CB ATFs have ear simulators fitted with GRAS 40BP microphones (6.35 mm diameter) that have amplitude limits of about 169 dB SPL (172 dB pSPL). The open ear transfer function measured at the 168-dB level can cause the peak amplitude to exceed the design specification of the microphone. Accordingly, the standard directs the user to measure the 150-dB transfer function between the field microphone and unoccluded ear (HFF,TM) and apply it to the field microphone measurement at 168 dB. We have measured the HFF,TM with GRAS 45CB ATF and with the GRAS 45CB-S2 ATF equipped with GRAS 40BH microphones (193 dB/196 dB pSPL). Impulse peak insertion loss measured with both ATFs will be reported and compared.
Local seismo-acoustic waves, but from the other side of the world
Authors: Assink Jelle D.
Published: November 2022

It is well understood that shallow seismic events near the Earth surface couple readily to the atmosphere where they can be observed as infrasonic waves. Typically, the observed sequence of infrasound arrivals includes a first arrival (i.e., “local infrasound”), which corresponds to the coupling of seismic body and surface waves to atmospheric infrasound, near an infrasound array. Under favorable atmospheric ducting conditions, additional coupled arrivals arrive later in time, having propagated throughout the (slower) atmosphere for part of the propagation path. In this presentation, we show that seismo-acoustic waves can couple from very deep earthquakes that occur on the other side of the world. This is demonstrated using seismo-acoustic observations from a M8.2 earthquake in Fiji that generated infrasound throughout Europe. Our analysis shows that various phases that reflected off the inner core boundary (ICB) were detected as pressure waves. This suggests that signals that are detectable on microbarometer arrays may have a surprising origin.
Experimental demonstration of scalable active metamaterials with interacting cells of tunable bulk modulus
Authors: Kovacevich Dylan , Popa Bogdan-Ioan
Published: November 2022

Active metamaterials can be designed to exhibit acoustic properties that are challenging to obtain using passive structures without relying on narrowband resonant behavior. Arrangements of unit cells that independently sense the local acoustic conditions and produce a coherent response, which is determined by the gain of electronics between the sensor and driver, act as a material with programmable properties. Such an active metamaterial has been previously demonstrated, but only for a single or a few non-interacting cells due to a limited understanding of how the programmed gains relate to the effective properties. Recently we developed a polarized source model to address this challenge, and based on that work we now demonstrate experimentally an active metamaterial composed of interacting cells with programmable bulk modulus. Each unit cell consists of a speaker and microphone mounted in the bottom plate of a 2D waveguide, with electronics of adjustable gain stored underneath. The field generated by a 2 × 3 arrangement of cells in response to an incident pulse was compared to the simulated scattered field of the equivalent continuous material. By tuning the gain, we accurately reproduced the behavior of a medium with negative, fractional, and large relative bulk modulus.
Optimization-based designs for communicating through impenetrable barriers with mechanical waves
Authors: Smith Chandler , Walsh Timothy , Akcelik Volkan
Published: November 2022

Piezoelectric-based acoustic energy transmission is an emerging alternative communication method that allows signal transmission across a barrier without wires or physical penetration. A major challenge in the design of an electrical-mechanical coupled communication channel is how to resolve the undesirable signal transformation known as acoustic multipath as the elastic wave propagates through a multi-layered deformable solid. Solutions largely investigated by the communications community are typically based on sophisticated signal processing methods. However, we approach the problem through the lens of computational mechanics and design optimization. Proposed method is to design a piezoelectric stack that mitigates acoustic multipath by optimizing the thickness of various stack layers and the material properties of the epoxy-based backing. We optimize the design parameters of a 3-D coupled electrical-mechanical finite element model using partial differential equation (PDE) constrained optimization. We leverage higher order polynomial elements (P-elements) and high-performance computing to solve the computationally expensive 3-D wave propagation problem in the MHz frequency range. The results demonstrate how finite element modelling and optimization can be used to achieve optimal physical channel designs for mechanical acoustic-based communication. [SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525.]
Broadband acoustic lens design using gradient-based optimization and adjusting radii and positions of scatterers
Authors: Amirkulova Feruza , Gerges Samer , Dabhade Vaishnavi
Published: November 2022

In this talk, we present the semi-analytical gradient-based optimization (GBO) technique for an efficient design of the broadband acoustic lens. This idea differs from earlier inverse designs that use topology optimization, shape optimization, and generic algorithms. We derived a formula for the gradients of the absolute pressure at the focal point with respect to positions and radii of a set of cylindrical scatterers. The derived analytic form of gradients of absolute pressure complements the modeling when combined with optimization and parallel computing. The GBO algorithm maximizes the sound amplification at focal point by evaluating pressure derivative with respect to the cylinder positions and radii, and then perturbatively optimizing the position and radius of each cylinder in the lens while considering acoustic multiple scattering between the cylinders. Computations are performed using the MultiStart Global optimization solver with fmincon while supplying the gradient of pressure at the focus and the gradient of nonlinear geometrical constraints. The GBO of the broadband acoustic lens is illustrated performing several performance measures for the dependency on the wavenumber and the incidence angle. The method is presented giving numerical examples for non-uniform configurations of the cylindrical structures of various radii and material submerged in water.
Digging into sentence intelligibility: Interactions with noise
Authors: Wright Richard A. , Kelley Matthew C. , Oganyan Marina , Tucker Benjamin V.
Published: November 2022

Implicit in the design of many intelligibility and perception studies is the assumption that noise masks all sentence stimuli equivalently, at least when they are controlled for length and structure. For example, controlled and normed sentences, such as the IEEE Harvard set, are typically thought to be equally affected by masker-noise. However, previous research has established that spoken stimuli of different structures, lengths, or complexities, are differentially masked (e.g. nonsense versus real words, words with different usage frequencies), therefore it is possible that masking affects even controlled sentences differentially . Using the UAW speech intelligibility dataset we analyzed Levenshtein Distance values based on transcriptions from over 900 native listeners of English to over 604 sentences from the UWNU IEEE sentence corpus. Each sentence was presented in noise at three SNRs ( + 2, 0, −2 dB). We find that the sentences are not equally intelligible. Moreover, there is an interaction with SNR level and sentence. In other words, the intelligibility of the sentences is impacted differentially by masker-noise. The results of this study suggest that, as researchers using speech stimuli, we should recognize that there are many sentence level factors that may introduce variance or otherwise affect the outcomes of our studies.
Clear speech promotes speaking rate normalization
Authors: Kahloon Lilah , Shorey Anya E. , King Caleb J. , Stilp Christian E.
Published: November 2022

When speaking in noisy conditions or to a hearing-impaired listener, talkers often use clear speech which is slower, louder, and hyperarticulated relative to conversational speech. In other research, changes in speaking rate are known to affect speech perception (called temporal contrast effects, or speaking rate normalization). For example, when a sentence is spoken quickly, the voice onset time (VOT) in the next word sounds longer by comparison (e.g., more like the /t/ of “tier”); a sentence spoken slowly makes the VOT in the next word sound shorter (e.g., like the /d/ of “deer”). Typically, one sentence is manipulated to produce fast and slow versions. We tested whether naturally produced clear and conversational speaking styles would also produce these temporal contrast effects. On each trial, listeners heard either a clear (slow) sentence or a conversational (fast) sentence followed by a target word to be categorized as “deer” or “tier.” Temporal contrast effects were observed both for conversational relative to clear speech and for conversational relative to a slowed version of the conversational speech. Changing speaking styles aids speech intelligibility but may produce other consequences such as contrast effects that alter sound/word recognition.
Linguistic fine-tuning in the spectra of the frequency-following responses to Mandarin tones
Authors: Kuang Jianjing , Zhao Tian C. , Llanos Fernando
Published: November 2022

Our understanding of the meaningful linguistic information encoded in neural signals such as FFR is still rather limited. Previous FFR tone studies mostly have focused on F0, and it is unclear how the other rich phonetic cues are encoded in the spectra. In this study, we analyzed the spectra of the frequency following responses to four Mandarin lexical tones from 13 native Mandarin listeners and 22 native English listeners. The stimuli consisted of four 250 ms synthetic syllable /yi/ with Mandarin four lexical tones minimally distinguished by F0 contours. In general, the harmonic structure of the FFR signals for native Mandarin listeners is much better defined than for non-native listeners, and the advantage is especially clear for higher-frequency harmonics. This result suggests that native listeners can hear the pitch contours more clearly and precisely not only because of a clearer f0 representation but also because of better-defined overtones. Moreover, for native listeners, harmonic representation varies by tonal targets. For a higher-pitched tone (Tone 1), H2 is the most prominent harmonic; for a lower-pitched tone (e.g., Tone 3 and Tone 2), H1 is the most prominent harmonic. These results suggest that pitch tracking strategies may vary by tonal targets.
The effect of listener dialect experience on generalization of a novel vowel shift
Authors: Bissell Marie , Clopper Cynthia G.
Published: November 2022

When adapting to novel dialects, listeners rely on the systematicity of novel variants across vowel categories, even when only part of the novel vowel system is presented. I examined how a listener’s dialect experience with components of a novel front lax vowel shift impacts perceptual adaptation and generalization. Three listener groups were exposed to different portions of a novel English dialect with front lax vowel backing. Listener groups varied in their dialect experience: Westerners were experienced with /ɪ ɛ æ/ backing in the California Vowel Shift, Southerners were experienced with parallel movements of /ɪ ɛ/ in the Southern Vowel Shift, and New Englanders were minimally experienced with parallel front lax vowel shifts. Listeners were exposed to either no front lax vowels, /ɪ/, /ɪ æ/, or /ɪ ɛ æ/. Then, listeners completed a lexical decision task for items with /ɪ ɛ æ/, requiring variable amounts of adaptation and generalization by condition. Westerners and New Englanders endorsed more words in the /ɪ æ/ exposure condition than in the /ɪ/ exposure condition, but Southerners endorsed fewer. Southerners’ unfamiliarity with /æ/ shifting may have inhibited adaptation and generalization. A listener’s dialect experience can affect perceptual adaptation to and generalization of a novel dialect.
A potential approach for reducing hearing difficulty by improving perception of intensity changes in speech
Authors: Maguire Aisling M. , Toscano Joseph C.
Published: November 2022

Many listeners report hearing difficulty, especially for speech in noisy environments, despite having normal audiometric thresholds. Recent work suggests that such cases may be caused by disruptions in coding of suprathreshold sounds at early stages of auditory processing. Specifically, differences in the function of auditory nerve fibers with lower spontaneous firing rates could disrupt coding of intensity changes for sounds in the typical range used for speech communication. In turn, this could affect perception of acoustic cues in speech that are dependent on intensity changes over time, such as voice onset time (VOT). The current study investigated a speech sound manipulation designed to counteract the effects of such disruptions by making intensity differences in the signal more pronounced. Listeners heard speech sounds varying along two acoustic dimensions that provide information about word-initial voicing, VOT and f0 onset, and categorized sounds as either voiced or voiceless. Results showed that the intensity manipulation reduced listeners' use of f0 for voicing categorization and also affected their use of VOT. This suggests that intensity manipulations can make acoustic cues like VOT more salient, providing a potential treatment approach for listeners who have difficulty coding intensity differences in speech.
Prosodic features conveying doubt and trust
Authors: Thomas Abbey L.
Published: November 2022

Research in affective prosody has shown that doubt (specifically, incredulity) is communicated through distinctive features like a slower speech rate, greater variability in fundamental frequency (F0), and a characteristic F0 pattern including an utterance final rise in F0. However, the opposite of doubt, trust (or belief), has not been examined as a prosodically distinct attitude. In response, this study explores the full range of doubt and trust native speakers of American English can express through prosody. In a web-based production experiment, we asked 30 participants to produce 12 utterances in neutral, trusting, and doubting prosody. A multinomial logistic regression analysis revealed that incredulous prosody differed significantly from neutral prosody primarily in its lower initial F0 and longer duration. Trust also differed from neutrality, with a significantly higher utterance initial F0 and less amplitude variability than was observed in neutral utterances. In a perception experiment, 115 participants listened to 36 tokens collected from the production experiment and were asked whether the talker expressed doubt or trust. Participants were generally accurate in their judgement of talker attitude, and acoustic variables of utterance-initial F0 and speech rate significantly predicted participant ratings of the talker's doubt or trust.
Analysis-by-synthesis paradigm evolved into a new concept
Authors: Kostek Bozena
Published: November 2022

This work aims at showing how the well-known analysis-by-synthesis paradigm has recently been evolved into a new concept. However, in contrast to the original idea stating that the created sound should not fail to pass the foolproof synthesis test, the recent development is a consequence of the need to create new data. Deep learning models are greedy algorithms requiring a vast amount of data that, in addition, should be correctly annotated. Annotation is a bottleneck to getting quality-reliable data as the process relies on annotating a person’s experience and, in many cases, personality-related issues. So, the new approach is to create synthesized data based on a thorough analytical examination of a musical/speech signal resulting in cues for a deep model of how to populate data to overcome this problem. Typically, a 2D feature space is employed, e.g., mel spectrograms, cepstrograms, chromagrams, etc., or a wave-based representation with the counterpart on the algorithmic side called wavenet. In this paper, examples of 2D musical/speech signal representation are presented, along with deep models applied. Creating new data in the context of applications is also shown. In conclusion, further possible directions of this paradigm development which is now beyond the conceptual phase, are presented.
Musical audio samples generated from joint text embeddings
Authors: Evans Zach , Hawley Scott H. , Crowson Katherine
Published: November 2022

The field of machine learning has benefited from the appearance of diffusion-based generative models for images and audio. While text-to-image models have become increasingly prevalent, text-to-audio generative models are currently an active area of research. We present work on generating short samples of musical instrument sounds generated by a model which was conditioned on text descriptions and the file structure labels of large sample libraries. Preliminary findings indicate that generation of wide-spectrum sounds such as percussion are not difficult, while the generation of harmonic musical sounds presents challenges for audio diffusion models.
Virtual Acoustics, better than the real thing? Considering the creative side
Authors: Woszczyk Wieslaw , Aydin Aybar , Zhang Ying-Ying
Published: November 2022

Once room acoustical reflections data are extracted from a physical space or a model, and are encapsulated in a 3D impulse response, they can be used to render immersive sound fields in real time. A range of possibilities then opens for creative use of acoustics in music. A skilled virtual acoustics designer-engineer may rebalance digital signals representing the room response to situate player and listener on the stage or at the back of the auditorium, may modify and arrange temporal segments to re-imagine the aural dimensions of the space, and apply gain and directional placement to shape the impression of immersive presence, adapting acoustics to musicians’ creative needs. In the process of building an idealized acoustical environment for the music, techniques of sound reinforcement and of rendering room acoustics are combined to balance presence with ambience and to deliver a sensation of acoustical power with lift-off. The means exist to move beyond acoustical realism into fictionalized acoustics.
Stochastic multiscale simulation of porous sound absorbing material based on adaptive bayesian quadrature
Authors: Komatsu Yosuke , Yamamoto Takashi
Published: November 2022

This presentation proposes a method to analyze porous sound absorbing materials by multiscale simulation with the adaptive Bayesian quadrature method. The homogenization method calculates equivalent physical acoustic properties from the microstructure of a porous material. This method is powerful in designing new porous materials because it can predict acoustic properties from arbitrary microstructures. On the other hand, it is difficult to consider the randomness of actual materials because of the assumption of periodic microstructures. We propose a method for quantifying uncertainty in acoustic properties by incorporating a Bayesian perspective into Gaussian process regression. Assuming the microscopic structure of porous material as random variables, the response obtained by the homogenization method is approximated by Gaussian process regression. Bayesian quadrature is used to calculate the statistical moments of the integral of the characteristic functions.An additional integration point that minimizes the variance of the integral is adaptively selected, and further responses are obtained using the homogenization method. Repeating this process shows that the integral of characteristic functions can be calculated accurately and efficiently, and their uncertainties can be quantitatively evaluated.
The roar of the rocket: A hot topics discussion
Authors: Gee Kent L.
Published: November 2022

An increasing number of companies and countries are building and launching space vehicles of different sizes and configurations for diverse purposes. The goal of this Hot Topics presentation is two-fold: first, to introduce a wide-ranging audience of Acoustical Society of America members to principles of rocket noise radiation, propagation, and reception; second, to discuss needs and challenges related to future launch vehicle acoustics research. If attendees leave both mildly entertained and better informed, the presentation will have been a success.