bluuebunny/crossref_metadata_2025 huggingface dataset:
Pseudospectrum-based methods for estimating the wind speed and direction based on closely spaced microphone signals
Authors: Mirabilii Daniele , Habets Emanuël A.
Published: April 2023

Acoustic array processing can be employed to measure the wind speed and direction based on microphone signals. Turbulent pressure fluctuations picked up by microphones are referred to as wind noise. According to Taylor's frozen turbulence hypothesis, turbulent eddies retain their shape while advecting at nearly the mean wind speed and in the wind direction. It follows that wind noise propagates accordingly across a microphone array when the inter-microphone distance is smaller than the turbulence wavelength. This property can be exploited to track the orientation of the turbulence advection, and hence to characterize the wind flow. We propose beamforming and signal subspace-based methods to estimate the wind speed and direction using a compact microphone array. In particular, the pseudospectrum of measured wind noise is computed against candidate pairs of wind speed and direction. The wind speed and direction estimates are then obtained as the maximizers of the pseudospectrum. In addition, we extend an existing time difference of arrival-based method originally derived for three microphones to an arbitrary number of microphones. We evaluate the estimation accuracy of the proposed methods separately for the wind speed and direction. Possible applications include highly integrable, portable, and inexpensive anemometers for smart sensors or action cameras.
Infrasound noise mitigation on high altitude balloons
Authors: Swaim Taylor , Spillman Kate , Hough Emalee , Yap Zach , Jacob Jamey , Elbing Brian R.
Published: April 2023

Wind noise significantly limits the use of infrasound for remote sensing using ground-based sensors. Recently, there has been a surge in studies using high altitude balloons, termed heliotropes, to mitigate this problem. Since the balloon drifts with the wind there is minimal relative speed between the balloon and the local air. To resolve the direction of arrival from a signal, there must be sufficient separation between sensors. However, this separation increases the relative motion between the sensors and the local air. On Earth this has shown to have a weak dependence, but the use of such measurements are currently being considered as a means of exploring the interior of Venus. Vertical shear on Venus is between 5 and 10 m/s per km, which will create approximately 1 m/s of relative wind speed per 100 m of separation. Thus, the current work aims to identify wind noise reduction schemes for balloon based infrasound sensing on Venus using an Earth analog. This presentation will report on a variety of windscreen configurations examined, ground-based testing of the designs, and heliotrope flight testing of windscreens.
Bio-inspired ultra-sensitive directional acoustic flow sensing using electro-spun nanofiber mesh over a close-back cavity
Authors: Lai Junpeng , Farahikia Mahdi M. , Karimi Morteza , Liu Zihan , Ke Changhong , Miles Ronald
Published: April 2023

Nearly two decades ago, it is shown that the mechanically coupled tympanic membrane ear of the Ormia fly can detect directional sound from a distance [1]. It achieves that by sensing the pressure gradient across the two coupled membranes. The recently discovered acoustic flow sensing using spider silk [2], opens new perspectives in acoustic sensing of particle velocity. Here we demonstrate an ultra-sensitive directional sensing scheme using a nanofiber mesh that is uniformly placed over the surface of a close back micro cavity. The nanofiber mesh can capture sound-induced velocity fluctuation well enough to represent the acoustic air particle velocity. Our result shows that the uniform sound field, which travels parallel to the fiber mesh plane, can drive the fiber mesh in and out of the cavity underneath. Since the small size of the cavity makes the air inside incompressible, the front and rear sides of the fiber mesh will move out of phase, much like the directional ear of the Ormia fly. By sensing acoustic air particle velocity and adopting the practical design of a back volume, this work provides a new approach for ultra-sensitive directional acoustic sensing. [1] R. N. Miles, D. Robert, and R. R. Hoy, “Mechanically coupled ears for directional hearing in the parasitoid fly Ormia ochracea,” JASA, 98(6), 3059–3070 (1995). [2] J. Zhou and R. N. Miles, “Sensing fluctuating airflow with spider silk,” Proc. Natl. Acad. Sci. U. S. A. 114(46), 12120–12125 (2017).
Using standards-based assessment and reporting in a general education acoustics course
Authors: Morrison Andrew C.
Published: April 2023

Standards-based assessment and reporting is a method of grading in which each student is responsible for demonstrating mastery of a set of course objectives called standards. In this course, students are assessed on each standard using short assessments that resemble a quiz, usually one or two pages long. Each standard is assigned a rating on a 5-step scale. The student's ratings throughout the semester determine the final grade the student will earn. If a student is not satisfied with a rating on an assessment, they are allowed to reassess the standard to demonstrate they have developed a fuller understanding of the topic. This method of student assessment is intended to encourage students to develop intrinsic motivation for learning the course material. Students are also not penalized for having a bad exam or quiz score due to unforeseen circumstances. Students often report that they need time at the start of the semester to get used to the grading system but that they ultimately see the benefit to their learning.
Tonal noise case study: Locating the source of tones on HVAC equipment
Authors: Mackenzie Roderick
Published: April 2023

The overall noise level measured from chiller units is controlled by primarily tonal noises from (1) the fans, (2) the compressors, and (3) the associated pipework. Three large chiller units were measured using AHRI 370 methodology to quantify the overall sound level spectra and A-weighted sound level from different chiller units in a range of environmental conditions. Whilst this method can identify a general area of tonal emission to within a couple of meters across a unit’s surface that is emitting discrete tonal noises, the method is limited when there are multiple potential tonal sources. Sound intensity imagery was used on two units to quantify the overall sound power emanating from the source, but also to offer a more advanced method of localizing the source of discrete tones to aid in the application of mitigation treatments. Results presented include visually displaying and quantifying the location of noise emission from fan blade pass frequencies and associated harmonics, localization of problematic tones emanating from individual pipework junctions and valves, and the reductions in sound power emissions achieved from lagging compressors and pipework.
Evaluating tonal noise in the outdoor environment
Authors: Lilly Jerry G.
Published: April 2023

Most outdoor noise criteria are based on the overall A-weighted sound pressure level evaluated at one or more location(s) on the receiving property. The maximum allowable sound pressure level is usually based on the zoning or actual use of the source and receiving properties. The referenced levels are often the Leq and/or the Lmax measured over a defined time interval, although the L(n) percentile statistical levels are sometimes specified. It is a well-known fact in the acoustics community that broadband sound at a given level is less annoying than sound with strong tonal components at the same sound pressure level. As a result, many state and local governments have included tonal penalties in their environmental noise ordinances to help compensate for this tonal annoyance factor. This presentation identifies several state and prominent local governments that have imposed such a penalty and how the government has elected to assess the presence of a tone that would warrant such a penalty.
Transcranial acoustoelectric imaging: Towards noninvasive mapping of current densities in the human brain
Authors: Witte Russell S. , Allard Margaret , Trujillo Teodoro , Alvarez Alex , Preston Chet , Kang Jinbum , O'Donnell Matthew
Published: April 2023

Acoustoelectric Imaging (AEI) is a disruptive technology that exploits an ultrasound (US) beam to transiently interact with physiologic or artificial currents, producing a radiofrequency signature detected by one or more surface electrodes. By rapidly sweeping the US beam and simultaneously detecting the acoustoelectric modulations, 4D current density images are generated at high spatial resolution determined by the ultrasound beam focus. The principle has been used for in vivo mapping of currents in the swine heart during the cardiac activation wave. When applied to the brain, transcranial acoustoelectric imaging (tABI) overcomes limitations with electroencephalography (EEG), which suffers from poor spatial resolution and inaccuracies due to blurring of electrical signals as they pass through the brain and skull, and, unlike fMRI and PET that measure slow metabolic or hemodynamic signals, tABI directly maps fast time-varying current within a defined brain volume at the mm and ms scales. This invited presentation will describe the underlying physics and mathematics of tABI, recent progress and challenges using numerical simulations and bench-top models, and its potential impact as a cutting-edge noninvasive modality for fast and accurate electrical brain mapping in humans.
Virtual imaging trials to investigate impact of skin color on three-dimensional optoacoustic tomography of the breast
Authors: Park Seonyeong , Villa Umberto , Oraevsky Alexander A. , Anastasio Mark
Published: April 2023

Optoacoustic tomography (OAT), also known as photoacoustic computed tomography, is being actively developed for breast imaging applications. The endogenous optical contrast in OAT images is associated with oxygen saturation and concentrations of chromophores, such as hemoglobin, melanin, fat, and water, within the tissue. In OAT breast imaging, near-infrared light propagates through the skin, where the optical energy is absorbed primarily by melanin. The photoacoustic effect results in the generation of a pressure wavefield, and the propagated pressure wavefield is measured by ultrasonic transducers located on a measurement aperture surrounding the breast. Thus, the melanin concentration influences lesion contrast in OAT images. However, the extent to which skin color affects lesion detectability in OAT breast imaging remains unexplored. To address this, we generate realistic optoacoustic 3D numerical breast phantoms containing a lesion at different locations (three depths and two polar angles) with five skin colors and virtually acquire optoacoustic data employing them. To assess the skin color impact on lesion detectability, we quantify numerical observer performance for a signal-known-exactly and background-known-exactly detection task. The results confirm that the signal-to-noise ratio of the test statistic is degraded in darker skin, and the extent depends on lesion locations and the light delivery system design.
Measuring the timeline of retroactive sentence repair
Authors: Gianakas Steven P. , Winn Matthew B.
Published: April 2023

Individuals with hearing loss are more likely to miss a word during speech perception, but can use context to retroactively repair the missing word. When sentences need to be repaired, listening effort remains elevated even after the entire sentence is heard; suggesting the repair process continues beyond the stimulus presentation. Importantly, if a listener is stuck processing a previous sentence, they may miss an upcoming utterance, making everyday conversation difficult. By measuring the amount of time that is needed to repair a missing word, we will better understand if processing would interfere with the perception of a subsequent sentence. Individuals with normal hearing and hearing loss heard sentences that did or did not require retroactive repair while performing a secondary case-judgement task. Listeners decided whether a visually presented letter was upper- or lower-case either during the sentence, 0.5 s after, or 2 s after the sentence. Preliminary results indicate that reaction times were faster for intact sentences and decrease (improve) as more time has passed (as the missing word has been resolved) for both sentence types. Our results suggest that the timeline of the repair process can be understood using behavioral measures that complement intelligibility scores.
Relating monaural and binaural envelope processing abilities to spatial release from masking
Authors: Barkhouse Morgan , O'Neill Sadie , Patro Chhayakanta , Srinivasan Nirmal Kumar
Published: April 2023

The difference in speech identification thresholds between colocated condition (when the target and the maskers are placed at the same location) and spatially separated condition (when target and the maskers are symmetrically separated) is quantified as Spatial Release from Masking (SRM). SRM is thought to be a combination of monaural and binaural advantages arising from spatially separating the target from the maskers. Monaural contributions are from the head shadow effect whereas the binaural contributions are from processing the interaural differences between the two ears. However, the exact contributions of the monaural and binaural advantage to SRM is unknown. Here, we present data on monaural and binaural envelope processing abilities and their relationship to SRM on a large cohort of young normal hearing listeners. Monaural envelope processing ability was measured using the envelope regularity discrimination task (Moore et al., 2019). Sensitivity to ITD-envelopes was used to quantify binaural envelope processing ability. SRM was measured using coordinate response measure sentences. The relationship between SRM, envelope regularity index, and ITD thresholds along with the monaural and binaural envelope processing abilities to SRM will be discussed.
Associations of acoustic parameters and gender dysphoria in transmasculine individuals
Authors: Lee Megan M. , Myers Brett R.
Published: April 2023

Gender dysphoria refers to a feeling of discomfort due to a mismatch between a person’s biological sex and gender identity. Voice is a secondary sex marker, and it may contribute to feelings of unease or dissatisfaction if the voice does not match a person’s gender identity. The Utrecht Gender Dysphoria Scale—Gender Spectrum (UGDS-GS) was designed to measure a person's degree of gender dysphoria. Transmasculine individuals were assigned female at birth and identify as male or masculine non-binary, and acoustic studies focusing on transmasculine voices are notably sparse. In a study including 20 transmasculine individuals, we compared UGDS-GS results to the following acoustic parameters: vocal tract length (VTL) estimates, fundamental frequency (f0), standard deviation of f0, and cepstral peak prominence smoothed (CPPS). We found a significant positive correlation between each acoustic measure and gender dysphoria. We also found robust associations between each of these measures and a voice-related quality of life measure. These findings indicate that the sound of one’s voice may be a strong predictor of gender dysphoria.
Evaluating remote post-fitting support services for over-the-counter hearing devices
Authors: Wheeler Harley J. , Nelson Peggy , Ellison John , O'Neill Erin
Published: April 2023

Over-the-counter (OTC) hearing aids are a more affordable and accessible option for many individuals with mild-to-moderate hearing loss. However, many clinicians and industry partners are apprehensive about how successful these new hearing aid (HA) users will be without the traditional support of audiologists. Much effort has gone into making the fitting and personalization of hearing aids accessible for OTC customers, but other post-fitting support services have not yet been translated to a remote format. Specifically, the individualized counseling audiologists traditionally provide is currently inaccessible to new HA users. The aim of this study is to explore ways of translating important aspects of audiologic counseling that contribute to satisfaction, use, and retention of HAs, to a format that is not dependent upon services provided within the clinic. Individuals with mild-to-moderate hearing loss were recruited and randomly assigned to one of three treatment groups: (1) a traditional clinical treatment model; (2) a model reflective of the typical “hands off” OTC experience; or (3) a non-clinical model with orientation and personalized counseling materials provided in a remote format. We hypothesize that individuals receiving personalized counseling remotely will be as successful as those receiving traditional clinical counseling, and more successful than typical OTC customers.
Investigating the neural correlates of the emergence of pitch using harmonic and inharmonic stimuli
Authors: Ferguson Anjelica , Mehta Anahita H.
Published: April 2023

The emergence of a pitch percept, referred to as the pitch onset response (POR), has predominantly been studied using transitions from noise to regular interval noise (RIN), click trains and more recently, harmonic complex tones. The POR is typically an asymmetrical change response which shows a larger response for stimuli that go from having no salient pitch to a salient pitch but not vice versa. However, the spectro-temporal differences between the pitch inducing stimulus and noise make it difficult to disentangle whether the response reflects a change in regularity or a true difference in pitch salience. The aim of this experiment is to use spectrally similar stimuli that differ in pitch salience (harmonic versus inharmonic tones) without changes in temporal regularity. We recorded EEG responses in normal-hearing participants to investigate the cortical correlates of pitch emergence in humans. We used the noise to RIN transitions as a baseline measure to replicate the asymmetry in the POR. We also used transitions from harmonic to inharmonic stimuli and vice versa to investigate if the POR asymmetry would hold for stimuli with minimal spectro-temporal differences. Results from this study will help us further understand the parameters affecting this response.
Tinnitus profile and speech in noise performance in military and non-military individuals: A comparative study
Authors: Jain Namitha , Kim Gibbeum , Tai Yihsin , Husain Fatima T.
Published: April 2023

Military-affiliated-individuals (MI) are more likely to develop hearing loss and tinnitus during training and deployment due to noise, ototoxic chemicals, and other events. There have been extensive studies about the incidence, prevalence, and functional impact of tinnitus in MI, but careful comparison of its impact between MI and non-military-individuals (NMI) is understudied. We aimed to compile and compare audiological and tinnitus profiles in MI and NMI. A total of 62 MI and 158 NMI were classified into four sub-groups; (1) normal hearing without tinnitus (NHCON); (2) normal hearing with tinnitus (NHTIN); (3) hearing loss without tinnitus (HLCON); and (4) hearing loss with tinnitus (HLTIN). Each participant underwent complete audiological, speech-in-noise assessments (QuickSIN) and tinnitus profiling. Our overall observations revealed that MIHL_TIN had higher tinnitus-related distress than NMIHL_TINin the relaxation subscale of tinnitus functional index. In MINH_TIN group perception of tinnitus was much louder than the NMINH_TIN. These findings highlight the importance of considering military status when developing assessment and management techniques. Military status had no effect on speech-in-noise scores, in both populations TINNH group outperformed the CONNH, while the TINHL group performed worse than CONHL. Better speech-in-noise performance in NHTIN may suggest heightened selective auditory attention or a potential spotlight phenomenon in this group.
Quantifying the impact of hearing-aid microphone placement and head-mounted devices on binaural cues from head-related transfer functions
Authors: Weeldreyer Gabriel S. , Peng Z. Ellen , Wang Lily M. , Stecker G. Christopher
Published: April 2023

Emerging techniques for assessment and training of spatial hearing use virtual reality (VR) devices to present auditory-visual cues. Sounds may be processed using head-related transfer functions (HRTFs), which capture directional acoustic cues, and visuals may be presented using a head-mounted display (HMD). For users of hearing devices such as hearing aids or cochlear implants, microphone placement may alter the binaural cues carried by the HRTF. Cues may also be distorted in presentations that combine HMD visuals with loudspeaker audio. This work seeks to understand these impacts by measuring and creating a database of HRTFs in the presence of hearing aids and HMDs. HRTFs were recorded within an anechoic chamber, using a standard manikin in a loudspeaker array located on the horizontal plane. Recordings were made with real sound sources of 5.625° resolution and virtual sources of 1° resolution. We will compare interaural time and level differences (ITDs and ILDs) from HRTFs measured through hearing-aid microphones with varied microphone placement (i.e., behind-the-ear and in-the-ear) and the presence versus absence of an HMD during the HRTF recording. Results will provide insights regarding HRTFs for individuals with hearing devices, as well as characterization of the HMD impact on VR-guided individual HRTF measurement.
Typical sound level in environmental sound representations
Authors: Oszczapinska Urszula , Nance Bridget , Jang Seojun , Heller Laurie M.
Published: April 2023

Although the sound level reaching a listener’s ear depends upon the sound source level and the environment, a stable source level can be perceived (McDermott et al., 2021). Nonetheless, variation in sound level can disrupt recognition in a short-term old/new task (Susini et al., 2019). We asked whether there is evidence of long-term memory of the typical level of everyday sounds. First, we found that listeners can report the level at which they typically hear a sound. Next, we compared sound judgements over headphones (ESC-50 dataset) across two conditions: (1) “typical”: levels set to produce the loudness experienced as “typical” for each sound (as determined by pilot studies); and (2) “equal”: levels at 70 dB SPL. Recognition, familiarity, and pleasantness were judged. There was no significant difference in recognition accuracy between level conditions and no interaction with whether sounds were louder or softer than their typical levels. In addition, recognition increased as sound familiarity increased, but this did not interact with level condition. Furthermore, consistent with past findings, sound pleasantness decreased as loudness increased, but this effect did not depend upon the condition. [Work supported by REAM.]
Resonant Willis metamaterials based on fractal geometry
Authors: Hart Carl R. , Muhlestein Michael B. , Best Cody M. , Blevins Matthew G. , Wilson D. Keith
Published: April 2023

A class of metamaterials that exhibit mass-momentum coupling are known as Willis materials. The mass-momentum coupling arises from hidden degrees of freedom that are asymmetrical with respect to the overall material. Resonant Willis metamaterials incorporate resonators, e.g., a Helmholtz resonator, along with material asymmetry to effectively obtain Willis coupling over a narrow frequency band. By incorporating fractal geometry into the resonator shapes Willis coupling can be obtained over a broader frequency range. This is accomplished by self-similar resonator shapes, which translates into resonance frequencies that exhibit a power-law dependence. Furthermore, manipulation of the internal asymmetry allows for tuning of the Willis coupling. This study reports on the measurement and modeling of resonant Willis metamaterials based on fractal geometry. Measurements are obtained with a transmission impedance tube, and predictions based on a lumped-element model. With resonator volume shapes based on the Sierpiński triangle, Willis coupling is obtained over a frequency range of 500 to 1500 Hz. Furthermore, for a subset of the resonators, Willis coupling is tuned by inverting the asymmetric location of the resonator necks.
Wave propagation in a phononic material with periodic bilinear elastic layers
Authors: Smith Elizabeth , Matlack Kathryn
Published: April 2023

This presentation discusses how bilinear elastic layers influence wave propagation in phononic materials. Bilinear elastic layers have been shown to produce wave propagation phenomenon such as shock waves, non-reciprocity,phase-reversal effects, and harmonic generation. Here, we examine how a propagating wave through a periodic array of linear elastic layers coupled with springs that exhibit bilinear stiffness can be tuned with the stress state of the excited wave. Using time-dependent finite element simulations, we study the interactions of bilinear springs and phononic materials, analyzing how the tensile or compressive stress state influences dispersion, band gaps, and energy transfer between frequencies. We select excitation waveforms to exploit the bilinear stiffness to fundamentally change the shape of the propagating wave. Results demonstrate phase-reversal effects, attenuation of tensile strain, and cumulative displacement offsets. To experimentally probe these results, bilinear stiffness couplings are physically realized by fabricating samples with prescribed delaminations between stiff and soft materials so the samples exhibit higher stiffness in compression than tension. Single layered samples are experimentally studied using both propagating waves and resonant methods. The nonlinear response from delaminations may be used to control frequency energy transfer and wave transformation for applications such as blast mitigation and passive mechanical sensing.
Computational and experimental analysis of lattices with modulated nonlinearity
Authors: Fronk Matthew D. , Sieck Caleb F. , Ikei Alec K. , Guild Matthew D.
Published: April 2023

There has been growing interest in wave propagation in nonlinear lattices due to their amplitude-dependent dispersion. While previous studies have primarily considered lattices with spatially-uniform stiffness nonlinearity, this work explores lattices with nonlinear stiffness spatially-modulatedin both sign and strength. A multiple scales perturbation analysis reveals exotic dispersion behavior, including the coexistence of hardening and softening within the same branch, the merging of two branches near the band edge, and the suppression of amplitude-dependent dispersion shifting across entire branches. Moreover, this study presents details of the computational and experimental validation of this newly-discovered nonlinear dispersion behavior. For numerical validation, direct simulation of the lattice equations of motion is carried-out. Distinctions are drawn between harmonic excitation of the lattice as compared to prescription of the lattice’s initial displacement and velocity fields. An experimental realization of the lattice is proposed whereby the sign and strength of the nonlinearity is spatially modulated using springs grounded at different angles. Experimentally-feasible lattice parameters are detailed and the experimental set-up is explored computationally using motion simulation and finite element software. [Work supported by the Office of Naval Research.]
Noise-induced change of tone dispersion in Cantonese speech
Authors: Zhang Ting , Li Bin
Published: April 2023

Noise effect on speaking non-tonal languages is reported on acoustic correlates including increased intensity, enlarged vowel space and raised fundamental frequency. Adverse influence may also be present in realization of tones, which however remains under-explored. Tone-space size and the according tone dispersion offer key indicators to the nature of a tonal system. The present study investigates whether and how Cantonese tones are modified in speaking under noise. Adult native speakers of Cantonese read tri-syllabic words embedded in carrier sentences in quiet and under multi-talker babbles. The speech materials cover six tones (T55, T25, T33, T21, T23, T22) and are balanced between high-low and low-high tone combinations to avoid biased articulatory effects. Results confirm Lombard speech effect in Cantonese speaking. Moreover, under the noise condition, tone spaces of all six tones are enlarged and tones are more dispersed, especially in realization of T55 and T21 that mark the upper and lower ranges of the tonal space. Changes in tone production by female speakers are more significant than those in male speech. This study provides new evidence of phonetic accommodation under noise and in particular noise effects on sizes of tone space, which is not found in the production of monosyllabic words in Cantonese. Our speakers may have used labored speech production to compensate for signal degradation under babble noise, leading to higher dispersion of tones than clear speech in quiet.
Contrast enhancement in clearly spoken Mandarin sibilants
Authors: Hauser Ivy , Zhang Xinwen
Published: April 2023

Clearly spoken sibilants have been shown to exhibit temporal, spectral, and amplitudinal enhancement, though most existing work focuses on English. This study presents acoustics of clearly spoken sibilants in Mandarin, which exhibits a three-way place contrast between alveolar, retroflex, and alveopalatal sibilant fricatives. Sibilant-initial stimuli were elicited in a carrier phrase and were crossed according to: sibilant (alveolar, retroflex, alveopalatal), vowel context (a u), word frequency, number of syllables, and tone. The participants were eight native speakers of Mandarin with origins in mainland China. The first block was a baseline with no instruction on speech style. In the second block they were instructed to speak clearly 'as if talking to someone hard of hearing'. In the third block they were instructed to speak conversationally 'as if casually talking to a friend'. As expected, speakers enhanced duration and amplitude in the clear speech block and reduced duration and amplitude in the conversational block. Departing from previous work, spectral moments were not significantly enhanced in clear speech, which could be due to differences in type of task. However, second formants of vowels following alveopalatal sibilants were significantly higher in the clear speech block. This would be expected if clear speech is generally contrast enhancing, as the second formant of the following vowel is known to be the primary cue distinguishing the alveopalatal in perception and production.
Perception error variation in masking contexts
Authors: Menon Aarya N. , Tucker Benjamin V.
Published: April 2023

Masking noise is an important tool in speech and hearing experiments. It provides a means to simulate real world conditions and provide misperceptions that are as naturally elicited as possible. However, the exact characteristics of the variable approach to this parameter is poorly understood. The present investigation explores the types and variability of errors across different noise conditions. The English Consistent Confusion Corpus [Marxer et al., JASA 140, EL458–EL463 (2016)], which provides data on consistently reproducible mispercepts, was used for this investigation. The dataset contains tokens of words in multiple masking conditions: speech shaped noise; three talker babble modulated noise; and four-talker natural babble, correlated with signal to noise ratios that bias a listener towards a specific mispercept. This dataset contains 3200 individual word tokens from four different speakers with 15 listeners. The interaction between types and variability of misperception with the different types of masking noise is explored. As well, the suitability of the different noise conditions for speech perception experiments is discussed.
Vowel focused training improves listener transcription of dysarthric speech
Authors: Krajewski Elizabeth , Olmstead Anne J.
Published: April 2023

Typical listeners can adjust to the speech of individuals with dysarthria through the process of perceptual learning. Past research has demonstrated that listeners improve in their recognition of both segments and connected speech produced by people with dysarthria. The mechanisms underlying learning of dysarthric speech are still uncertain, though it has been suggested that exposure allows listeners to tune into the segmental characteristics of speech. In the current study, we test this hypothesis by training listeners to identify vowels spoken by an individual with mild dysarthria. We employed a pre-test/post-test design where we first tested listeners on (1) vowel recognition and (2) transcription accuracy of connected speech, trained them, and then tested them again. We found that listeners who were trained on dysarthric vowels demonstrated greater improvements in vowel identification than those in the control condition. Likewise, the listeners who underwent training showed greater improvements in transcription accuracy than those in the control condition. However, the training advantage did not generalize to unfamiliar phrases. Overall, it appears that listeners are able to tune into the segmental characteristics of dysarthric speech after a short training session, which improves their recognition of longer connected speech.
The Children’s English/Spanish Speech Recognition Test (ChEgSS): Feasibility, Reliability, and Normative data
Authors: Leibold Lori , Buss Emily , Miller Margaret , Cowan Tiana , McCreery Ryan , Oleson Jacob , Rodriguez Barbara , Calandruccio Lauren
Published: April 2023

The Children’s English/Spanish Speech Recognition Test (ChEgSS) is a computer-based tool for assessing closed-set word recognition in either speech-shaped noise or two-talker speech. Instructions and stimuli are recorded in both languages, and listeners respond by pointing to the picture depicting the word that they heard. Preliminary clinical feasibility and reliability data will be presented, along with age norms for children (4.1–17.0 yrs) who are either English monolinguals (n = 89) or Spanish/English bilinguals (n = 83). Results obtained with the two maskers will be evaluated with respect to age, language group, and receptive vocabulary. SRTs in English were higher in two-talker speech than speech-shaped noise and were 1.7dB lower for monolinguals than bilinguals for both maskers. SRTs were lower in English than Spanish for bilinguals in noise but not significantly different in speech. Consistent with prior research, SRTs in both languages improved with age; effects of age were more pronounced and prolonged in two-talker speech than in speech-shaped noise. The mean discrepancy between replicate estimates of SRT in English were 1.8 dB in noise and 3.1 in two-talker speech. Overall, these results suggest ChEgSS may be a valuable tool for clinical assessment of masked speech perception in children.
Effects of age and musical expertise on perception of speech in speech maskers in adults
Authors: Harding Eleanor , Rachman Laura , Gray Ryan , Smeenk Stefan , Sarampalis Anastasios , Gaudrain Etienne , Başkent Deniz
Published: April 2023

Perceiving “cocktail party” speech, or speech-on-speech (SoS), requires perceptual mechanisms such as segregating target from masking speech using voice cues, and on cognitive mechanisms such as selective attention and inhibition. Both aging and musical expertise have been shown to affect these mechanisms. Voice cues that help distinguish different speakers include mean fundamental frequency (F0), related to voice pitch, and the vocal-tract length (VTL), related to speaker size. Some studies reported older adults’ decreased sensitivity to F0 differences, possibly affecting their ability to discriminate speakers. Furthermore, age-related cognitive changes may lead to difficulties in attention direction and inhibition. Compared to non-musicians, musicians are reported to show enhanced processing of acoustic features such as F0, as well as enhanced cognitive abilities such as auditory attention skills and working memory. While this intuitively could lead to a musician advantage for SoS, reports of musicians outperforming non-musicians are inconsistent across both younger and older adults. Differences across previous SoS paradigms have made comparison of musicianship advantages in SoS in younger and older adults—and underlying mechanisms—difficult. Therefore, we investigated the extent to which older compared to younger adults benefit from either musical expertise or F0 and VTL differences between target and masker voices.
Effects of frequency-to-place mismatch in children listening to simualted unilateral and bilateral cochlear implant configurations
Authors: Gross Julianna , Cychosz Margaret , Fu Qian-Jie
Published: April 2023

Binaural cues are important for spatial speech recognition. While binaural cues can be partly restored by bilateral cochlear implants or a unilateral cochlear implant in patients with single-sided deafness, the benefits may be limited by frequency-to-place mismatch in both cases. Previous studies reported worse recognition of spatially separated speech as frequency-to-place mismatch increased in typical-hearing adults listening to acoustic simulations of bilateral cochlear implants (Thomas et al., 2022). This work also revealed that children were more sensitive to the spectral degradation and less able to use spatial cues for spatial speech recognition. The present study investigates the effects of frequency-to-place mismatch on binaural fusion in typical hearing children (7–9 years old) listening to acoustic simulations of bi- and unilateral cochlear implant configurations. The stimuli in the left ear were either unprocessed or processed by a 16-channel sinewave vocoder with a fixed insertion depth while the stimuli in the right ear were processed by 16-channel sinewave vocoders with varying insertion depth. Speech recognition threshold results from N = 10 children show an effect of interaural insertion depth mismatch upon speech recognition thresholds, with no differences by age. Comparisons with adult data will likewise be reported.
Can unsupervised machine learning help us understand the data collected in the ocean?
Authors: Chen Wesley , Neilsen Tracianne B.
Published: April 2023

Since the ocean is not a convenient place to conduct research, data are often collected from offshore buoys. However, the data collected from the buoys usually do not have labels (e.g., source of the sound) attached to them. Manually labeling the data is time-consuming, but labeled data are necessary to use powerful supervised machine learning methods. We propose that unsupervised learning can be used to assign preliminary labels to data samples. To show the utility of this approach, we took an echosounder to Utah Lake and collected sonar images, some of which showed evidence of fish. We used Python to crop the images, similar to how regions of interest are identified in image processing. These cropped images are used in an unsupervised k-means clustering algorithm. The images are clustered based on visual features. An analysis of the resulting clusters and the feasibility of using unsupervised learning to provide preliminary labels to data is discussed.
Information geometry for environmental inversions in ocean acoustics
Authors: Transtrum Mark K. , Spendlove Jay C. , Neilsen Tracianne B.
Published: April 2023

Environmental inversions in ocean acoustics require the simultaneous estimation of many unknown parameters. Broad studies of multi-parameter models from diverse fields have shown that such inference problems are universally sloppy. Sloppiness is a phenomenon in which the predictions of a model are insensitive to all but a few key combinations of parameters. Sloppy model analysis is based on information geometry, an application of differential geometry to statistics. In this talk, we give an overview of information geometry for underwater acoustics models for environmental inversion, focusing on transmission loss (TL) in range-independent normal mode models. We demonstrate that these models are sloppy and how the geometry directly relates the information content of acoustic data to the relevance of environmental parameters. In particular, the model manifold quantifies what environmental information is encoded in ocean sounds and how unidentifiable parameters can be removed from the model to give a simplified, identifiable ocean acoustics model of comparable accuracy. We summarize physical insights revealed by this information geometry analysis for ocean inversion. [Work supported by Office of Naval Research]
Seabed classification with ResNet-18 using multi-channel ship noise spectrograms
Authors: Lau Ginger E. , Neilsen Tracianne B. , Knobles David P. , Hodgkiss William
Published: April 2023

Transiting cargo ships in the ocean generate noise that can be used to infer the effective seabed type below. Recently this has been demonstrated with a residual convolutional neural network trained on synthetic data that displays frequency and range-dependent transmission loss generated by a range-independent normal model and empirical source spectrum for ship noise. The generalizability of the trained model was tested on ship noise measured from the middle sensor of a 16-channel vertical line array near shipping lanes on the New England continental shelf. In contrast, this current work utilizes multiple sensors and seeks to determine the optimal combination of sensor data. It was discovered that including sensors near the seabed improved model performance. Best results were obtained when the model’s average sensor depth was 75%–80% of the water depth. The distance between sensors had no discernible effect on performance. Although the almost isovelocity sound speed profile used in this study indicated little difference between one-channel and two-channel model performance, future analyses will test the hypothesis that the use of multiple sensors will improve model performance for greater sound speed variation. [Work supported by the Office of Naval Research and the National Science Foundation REU program.]
Machine learning a surrogate model for transmission loss on a Pekeris waveguide
Authors: Spendlove Jay C. , Transtrum Mark K. , Neilsen Tracianne B.
Published: April 2023

The connection between ocean environmental parameters and transmission loss (TL) can be modeled using sound propagation models. We can analyze and improve these models using information theoretic tools such as the Fisher information matrix (FIM) and methods for model reduction, where we identify parameters that can be removed from a model without sacrificing accuracy. Critical to these methods for model reduction is the ability to evaluate derivatives of the model predictions of TL with respect to model parameters. Calculating derivatives of TL models using finite difference methods with sufficient accuracy is challenging due to the complexity of sound fields in an ocean environment; instead, we train a surrogate machine learning model to which we can apply automatic differentiation (AD). We propose a general method for model reduction in which a ML model is used as a surrogate model for physical sound propagation ocean models, which is then used to find potential simplifications of the original model. We demonstrate this method using the Pekeris waveguide model of the ocean, which calculates underwater acoustic TL in an ocean environment due to seafloor characteristics. [Work supported by Office of Naval Research]
Sonar feature representation with autoencoders and generative adversarial networks
Authors: Linhardt Timothy , Sen Gupta Ananya
Published: April 2023

Feature representation in the littoral sonar space is a complicated field due to prevalent channel noise from sound reflections as well as diffraction. The response of a sound wave as it interacts with an object provides insight into the nature of the object itself such as geometry and material composition. We approach automated target recognition in this space with feature representation using autoencoders and generative adversarial networks. Through empirical analysis of learned encoding spaces, the dimensionalities of principal features in our sonar data sets are estimated. Real and complex valued training data, processed in various ways, is used to refine which features are represented, and evaluate the importance of phase information while encoding the data. [This research was funded by The Office of Naval Research with Grant No. N00174-20-1-0016.]
The creation of functional standards to streamline ASTM standards in committee E33 on building and environmental acoustics
Authors: Golden Matthew
Published: April 2023

ASTM E33 standards are in wide-spread use in North America in building and environmental acoustics. Some of these standards have been in existence in one form or another for over 60 years. There are now 55 standards within the E33 committee all created by different volunteer authors at different times. Each of these standards is periodically updated by other volunteers. While efforts have been made to keep agreement among these standards, subtle and not so subtle differences creep up in similar measurements, calculations, and specifications. A small working committee has identified 21 topics that are candidates for consolidation into “functional” standards. These functional standards will be used similarly to a computer program function and can be “called” from any other standard. The hope is that this will remove inconsistences among the standards and make the standards easier to read. The current status and future plans of this project will be shared.
Quantifying repeatability, reproducibility, and bias in sound power level measurement methodologies via a round-robin study
Authors: Underwood Samuel H. , Wang Lily M.
Published: April 2023

This paper presents results from an interlaboratory study to examine the repeatability, reproducibility, and bias of three different sound power measurement methods used in the heating, ventilation, and air-conditioning industry: free field method, diffuse field method, and intensity method. A loudspeaker playing both a broadband signal and a broadband signal with four discrete tones has been measured in participating laboratories according to the standardized test methods that are commonly used in each facility. Results across 1/3 and 1/1 octave bands are then compared between signals, between methods, between laboratories, and across all laboratories using the same method. Additional discussion regarding potential sources of variation between facilities is presented. Ultimately, in accordance with ISO 5725, repeatability, reproducibility, laboratory bias, and test method bias are estimated. To reduce uncertainty of these estimates for some methods, additional laboratory participants are needed. [Work supported by the Air-Conditioning, Heating, and Refrigeration Institute.]
A new measurement method for floor-ceiling assembly performance with improved reproducibility
Authors: Girdhar Sunit , Barnard Andrew , Blough Jason R. , Lo Verde John , Dong Wayland
Published: April 2023

ASTM standards are used to calculate a single number performance rating for floor-ceiling assembly impact noise. A higher number represents better performance, and a lower number represents poor performance. This number is calculated by placing a standard tapping machine on the floor and measuring the radiated sound pressure level (SPL) in the receiving room below. In theory, the performance of an assembly can be represented by just this calculated number. In practice, however, the same assembly tested in the same configuration can lead to a range of single-number ratings, instead of just one number. This variation primarily comes from the SPL measurement, which is highly variable in different parts of the room at low frequencies because of the existence of a non-diffuse sound field. This variation in SPL measurement for the ASTM standards leads to a high non-reproducibility which may cause confusion among the consultants and the clients. In our work, we are proposing a new measurement method with improved reproducibility in low frequencies.