bluuebunny/crossref_metadata_2025 huggingface dataset:
Overcoming biases in state-of-the-art automatic speech recognition for young children with speech disorders
Authors: Shrivastava Vishal , Speights Marisha
Published: January 2025

State-of-the-art models like Whisper and GPT-4o face significant challenges in recognizing and processing child speech, particularly disordered speech, due to the limited availability of annotated child speech data and inherent demographic biases. Our research aims to bridge this gap by adapting these models for more accurate classification and recognition of disordered vs. non-disordered child speech. Using the SEED corpus, we leveraged advanced data augmentation, transfer learning, and parameter-efficient fine-tuning, achieving significant Word Error Rate (WER) reductions: from 57.5% to 10.3% for disordered speech and from 33.6% to 6.04% for non-disordered speech. Our novel approach also addresses demographic biases, ensuring equitable ASR performance across diverse groups. By overcoming current methodological constraints and emphasizing fairness and precision, our research not only advances ASR capabilities but also establishes a benchmark for inclusive technological advancement. These developments are crucial for practical applications in speech therapy and education, showcasing our commitment to impactful research in this domain. Future plans include enhancing model robustness by incorporating self-supervised learning techniques and exploring domain adaptation to ensure adaptability across varied speech environments. This comprehensive approach represents a significant step forward in signal processing, providing robust solutions to longstanding challenges in child speech recognition.
(Non)assimilation of consonant clusters in phonological conditioning: An acoustic study
Authors: Osei-Bonsu Gifty , Lomotey Charlotte F.
Published: January 2025

In phonological conditioning, phonemes become assimilated to match the properties of adjacent phonemes. At the syllable coda morpheme boundary in the English language, these morphemic elements express grammatical features of marking number (plural) and genitive ( singular and plural possession ) in regular nouns, and the 3rd person singular and past tense in regular verbs. These morphemes create consonant clusters that are expected to assimilate for easy production (or linguistic economy). Unfortunately, it has been revealed that non-native speakers do not always assimilate the consonants to reflect this conditioning. This study investigates the (non)assimilation of consonant clusters in phonological conditioning from an acoustic perspective. It uncovers the patterns of phonological conditioning that are derived from (non)assimilation of consonant clusters in Ghanaian English and the factors that account for such patterns using the Speech Learning Model (SLM) by Flege (1995) and the Markedness Differential Hypothesis by Ekman (1977). Six (6) hours of data recorded from 50 Ghanaians were subjected to auditory and acoustic analyses. Results indicate that Ghanaian speakers of English sometimes assimilate these phonological endings correctly but mostly deviate from inner circle expectations. Typically, while they assimilate the voiceless endings, the voiced endings most often pose a challenge to them. Keywords: assimilation, consonant clusters, phonological conditioning, morphophonemic orthography, markedness
Representing Tone in Onomatopoeic Expressions
Authors: Zimmerman Joey K.
Published: January 2025

My research seeks to clarify what specific acoustic properties that humans use to represent sounds in onomatopoeia, in the specific domain of tone. A wealth of research (Tanaka et al. 1995, Yamauchi et al. 2003, Yamauchi and Iwamiya 2005, and Matsui 2020, etc.) has find that, when representing pure tones as onomatopoeia, native Japanese speakers will use F2 as a proxy for f0. This has also been found to be true of native Mandarin speakers (Matsui 2020). Yet, it has not been determined whether this is also true of speakers of a non-tonal langauge, like English, and whether this association is one sided. My ongoing study will be conducted on 30 native English speakers and 30 native Mandarin speakers. In the first part, which reuses the methodology of existing research, participants will be asked to listen to pure tones of 62.5, 125, 250, 500, 1000, 2000, 4000, and 8000 Hz and represent them as an onomatopoeia. In the second part, which will be administered only to Mandarin speakers, participants will undergo a 2-AFC task where they must categorize tokens from a tonal minimal pair. All of the tokens have been high-pass filtered to obscure tone and have F2 altered to be higher or lower than normal. Preliminary results indicate that English speakers do use F2 as a proxy for f0.
Acoustic voice assessment reliability in varying reverberation times
Authors: Yousef Ahmed , Hunter Eric
Published: January 2025

Objective: Acoustic voice and speech assessment is a non-invasive and cost-effective tool for the clinic and the laboratory. However, the effect of room environment can impact the voice and speech metrics. This study investigates the threshold levels of simulated reverberation times above which acoustic measures become unreliable for voice quality assessment. Methods: Fifteen male and female subjects were recorded producing the sustained /a:/ vowel three times in a sound booth. Using Audacity software, the recordings were mixed with various simulated reverberation levels (T30). Acoustic measures related to voice quality assessment—such as shimmer, jitter, Cepstral Peak Prominence (CPP), and Harmonics-to-Noise Ratio (HNR)—were estimated for both original and reverberation-affected recordings. Statistical analyses were performed to determine significant differences in these measurements across the different reverberation levels. Results/Conclusions: The analysis demonstrated that CPP and jitter were more robust against high reverberation levels, showing high T30 threshold values, while shimmer and HNR were more vulnerable to reverberant rooms with low T30 threshold values. The outcomes recommend specific reverberation thresholds in clinics and recording environments for accurate acoustic measurements. Identifying these reverberation limits aids in optimizing recording environments and establishing standard room conditions for reliable acoustic voice assessments.
A phonetic basis of accent bias in speaker identification technology
Authors: Bakst Sarah , Pearson Ebony , Ferrer Luciana , McLaren Mitchell , Lawson Aaron
Published: January 2025

Speaker identification (SID) technology aims to determine whether the speech in a recording of an unknown speaker matches that of speaker known to the SID system. If the unknown speaker comes from a community that is underrepresented in the SID training data (e.g., accent), the SID model is more likely to confuse the unknown speaker for other speakers in that speaker community: group-level characteristics are mistaken for individual identifiers (all speakers with that accent seem like the same speaker to SID). Previous solutions include reweighting training data to create balance across speaker groups. While effective, such solutions are insufficient because they require foreknowledge of all potential speaker groups to be tested. The present study seeks a solution by first understanding how group-level characteristics are represented in SID models, focusing on dialect diversity within first-language English speakers. We hypothesize that filter properties (e.g. vowel formants) are more heavily represented in SID models than other uniquely-identifying spectral components. Preliminary results show that speaker clusters based on vowel measures alone are dissimilar to clusters formed by the SID model representations (embeddings) extracted from the same recordings—except for certain underrepresented accents (African American Language), suggesting SID representations of speech differ by speaker group.
Frequency and context prominence effects on English allophone perception: Identification of /r/ and /
θ
/
Authors: Gurevich Naomi , Aalto Daniel
Published: January 2025

Purpose: External evidence from multiple cross-linguistics studies suggests the importance of acoustic clarity of speech sounds in words can vary for decoding speech (Gurevich & Kim, 2023b). Dependence on acoustic salience is modulated by the structure and function of words (Bell et al., 2003; Jun, 2011; Jurafsky et al., 2001; Scharenborg et al., 2016). This perception study of English examines the functional importance of positional allophones to intelligibility. Methods: Speech produced by 21 speakers reading five randomized lists of 308 words with high coverage of English allophones (from Gurevich & Kim, 2023a) was presented to 11 naïve listeners for identification using a Latin-square design. The identification accuracy of the highest and the lowest frequency sounds were compared in their most and least prominent positions. Results: A total of 257 perceptual judgements were analyzed. Word-initial prevocalic /r/ and /θ/ had 97% and 75% accuracies, respectively; the pre-consonantal /r/ and inter-consonantal /θ/ had 95% and 43% accuracies, respectively. Conclusions: The results experimentally corroborate the expected hierarchy where higher frequency allophones in prominent contexts show higher accuracy compared to lower frequency allophones in less prominent contexts. Investigating allophones in additional languages will explore the effect of phonology on perception.
From analysis-by-synthesis to predictive coding and beyond: The Martingale Dynamics of Human Speech
Authors: Ramsay Gordon
Published: January 2025

Ken Stevens is best remembered for his seminal contributions in developing theories of speech perception based on detection of acoustic features emerging from quantal properties of speech. Equally influential, however, is his earlier proposal for speech perception through analysis-by-synthesis, whereby hypotheses generated by an internal model of speech production are evaluated against sensory input. These ideas are recapitulated in recent theories of predictive coding, which also rely on monitoring discrepancy between simulations of potential action and actual sensation. Analysis-by-synthesis and invariant feature detection are often considered as alternative top-down and bottom-up approaches to explaining perception. Both viewpoints can, however, be reconciled within mathematical theories of optimal estimation, which offer two alternative, equivalent solutions to the problem of extracting information about the state of a dynamical system from partial observations. Both solutions rely on internal models, but one involves calculating the prediction error, as in analysis-by-synthesis, whereas the other involves calculating the relative salience of the sensory field, akin to landmark detection. This presentation provides a historical overview of analysis-by-synthesis, from cybernetics to predictive coding, and also reviews parallel developments in martingale dynamics that unite analysis-by-synthesis with landmark detection.
Three-dimensional finite element acoustic analysis of bent vocal tracts
Authors: Mohapatra Debasish Ray , Fels Sidney
Published: January 2025

The bent air column in a vocal tract can significantly impact its acoustic characteristics by altering formant frequencies. However, existing vocal tract models typically assume the tract to be a straight three-dimensional (3D) tube with varying cross-sectional areas. Although wave propagation in realistic vocal tracts has been previously studied, the acoustic effect of the tract curvature on resonance frequencies has yet to be thoroughly explored. In this work, we use a state-of-the-art 3D finite element (FE) wave solver to characterize the effect of bending in acoustic ducts, akin to vocal tracts, by comparing their transfer functions up to 14 kHz. The duct geometries are modified to match vocal tracts for vowels /a/ and /u/. For a comparative analysis, we empirically adjust the degree of bending for a portion of the duct to increase its geometrical complexity. Our result shows that the bent air column does not significantly affect acoustic output for ducts with uniform cross-sections. However, transverse modes appear at higher frequencies for bent vocal tract geometries, i.e., ducts with varying cross-sectional areas. The comparison of transfer functions also shows that above 7 kHz, there is a notable shift in formant frequencies for such duct geometries.
Internal /r/ epenthesis as gestural overlap in a memphis English emergent sound change
Authors: Norris Sydney M. , Walter Maddy , Villasenor Melissa , Phoenix Maya , Gick Bryan
Published: January 2025

Temporal overlap of speech movements has occasionally been invoked as a post-hoc explanation for the historical emergence of a complex speech sound. An extreme case of this concerns so-called “internal” r-epenthesis in English dialects, limited to lexicalized pronunciations such as “warsh,” “Warshington,” “squarsh,” and “garsh” in the Midland US, as well as “erster” and “berl” (for “oyster” and “boil”) in many coastal dialects [Gick, 1999, Phonology 16]; Gick (p. 33, 50–51) hypothesizes an originating process for these forms in which the three component movements of English /r/ (i.e., lip-rounding, anterior tongue-raising and pharyngeal constriction), all present in the surrounding “rising” VC or VV sequences, temporally overlap, resulting in the “percept of an /r/.” However, this hypothesis has been untestable as only two such examples are attested, both representing long-frozen sound changes. We report an apparently relevant in-progress sound change in Memphis English (ME), a dialect exhibiting the Southern Vowel Shift [Fridland, 1999, Lang. Var. Change 11]. Videos of younger ME speakers are analyzed in which internal r-epenthesis is replacing the falling diphthong [ju] in words, such as “human,” “Cuba,” “music,” etc. Preliminary observations support a temporal overlap hypothesis; acoustic/structural analysis will be presented and implications discussed.
Generational dynamics in velar palatalization: An acoustic study of Tohoku Japanese
Authors: Watabe Naoya , Huang Chuyu , Mizoguchi Ai , Noguchi Hiroto , Hashimoto Ayako , Kitahara Mafuyu , Kimoto Megumi , Matsui Sanae
Published: January 2025

This study examines the contextual and generational differences in consonantal palatalization of Tohoku Japanese compared to Tokyo Japanese. Typically, both Japanese dialects transform alveolar obstruents to alveo-palatals before /i/. Moreover, previous research has shown that Tohoku Japanese also exhibits palatalization of velar stops /k, ɡ/. However, this palatalization ceases to appear among the younger generations despite the scant acoustic evidence. This study aims to: (i) describe the occurrence of velar palatalization in Tohoku Japanese and (ii) analyze variations between Tohoku and Tokyo Japanese by socio-demographic factors including age and gender. Twenty-five speakers from Tohoku and twenty-one from Tokyo participated in a production task using target words containing /k/ in the /ki/ and /ka/ contexts, and /ʨ/ as the palatalization baseline. The results of Center of Gravity (CoG) revealed significant interactions between the target consonant, dialectal group, and age group in the palatalization patterns. Younger speakers of Tohoku Japanese show a similar CoG distribution that resembles those of Tokyo speakers, particularly in the pairwise comparison of /k/ in /ki/ and /ka/. This empirically suggests a converging shift among young Tohoku speakers toward the standard variation of Japanese, supporting a diminishing regional variation correlated with consonantal context and influenced by generational change.
Improving transparency and adaptability of undersea object recognition systems
Authors: DeYoung Luke , Swaters Alexander , Barsic Dave
Published: January 2025

Side-scan sonars are commonly deployed on autonomous underwater vehicles for seafloor imaging and search applications. In recent years, deep neural networks have become a common solution for object recognition problems with these systems, achieving impressive performance. However, adaptability and interpretability of these systems remain a challenge. The models used in these systems are typically tuned for recognition of specific categories of objects and, due to the labor required to create segmentation mask labels, are often limited to bounding box prediction. Meta's Segment Anything Model (SAM), released in 2023, provides a solution to add instance segmentation capabilities to existing object recognition systems. SAM may be fine-tuned on side-scan sonar data to predict separate object and acoustic shadow masks, allowing for automatic and robust measurement of undersea objects. In addition, this fine-tuned variant of SAM may then be integrated with existing object recognition algorithms tuned for side-scan sonar image analysis to transform them into instance segmentation algorithms. The end result is a highly descriptive recognition system with customizable reporting behavior based on the dimensions of the object(s) of interest.
Explainable AI for trustworthy image analysis
Authors: Turley Jordan E. , Dunne Jeffrey A. , Woods Zerotti
Published: January 2025

The capabilities of convolutional neural networks to explore data in various fields has been documented extensively throughout the literature. One common challenge with adopting AI/ML solutions, however, is the issue of trust. Decision makers are rightfully hesitant to take action based solely on “the computer said so” even if the computer has great confidence that it is correct. There is obvious value in a system that can answer the question of why it made a given prediction and back this up with specific evidence. Basic models like regression or nearest neighbors can support such answers but have significant limitations in real-world applications, and more capable models like neural networks are much too complex to interpret. We have developed a prototype system that combines convolutional neural networks with semantic representations of reasonableness. We use logic similar to how humans justify conclusions, breaking objects into smaller pieces that we trust a neural network to identify. Leveraging a suite of machine learning algorithms, the tool provides not merely an output “conclusion,” but a supporting string of evidence that humans can use to better understand the conclusion, as well as explore potential weaknesses in the AI/ML components. This paper will provide an in-depth overview of the prototype and show some exemplar results. [Work supported by the Johns Hopkins University Applied Physics Laboratory.]
Uncertainty-aware classification of underwater acoustic signals using Bayesian deep learning
Authors: Orescanin Marko
Published: January 2025

This talk presents our work on applying Bayesian deep learning methods to provide interpretable and uncertainty-aware classification of underwater acoustic signals. We demonstrate how Bayesian convolutional neural networks can accurately classify both passive sonar and synthetic aperture sonar data while quantifying prediction uncertainty—a critical capability for autonomous systems. By examining estimated aleatoric and epistemic uncertainties, we gain insight into the model's decision-making process and areas of low confidence. We leverage predictive entropy and calibrated uncertainties to identify challenging samples, explain misclassifications, and reveal patterns in model behavior. Our results show how uncertainty correlates with factors like range, aspect angle, and seafloor texture in ways that align with acoustic propagation physics. We also discuss how active learning strategies guided by epistemic uncertainty can efficiently train models while providing further model interpretability. This work establishes Bayesian deep learning as a promising approach for developing explainable and reliable underwater acoustic classifiers, addressing the need for transparency in AI-driven underwater sensing applications.
An analysis of spatial impulse response measurements and their ability to validate spatial features within an acoustic model
Authors: Latta John , Ronsse Lauren
Published: January 2025

Conventional impulse response measurements are commonly used to validate omnidirectional metrics within ODEON models. ODEON models can also provide further analysis of the spatial properties of spaces. However, the spatial properties of a model cannot be validated using exclusively conventional measuring techniques. Instead, spatial impulse response measurements must be performed to properly validate the spatial components of an ODEON model. Conventional impulse and spatial impulse response measurements performed at the Recital Hall in the Strauss Performing Arts Center at the University of Nebraska at Omaha were used to create and validate acoustic metrics of an ODEON model of the same space. These spatial impulse response measurements contained visualizations of directional energy over time to assess reflections. ODEON produces several graphics comparable to those produced by the measurements. Across both visualization results, early reflections are nearly identical. However, at late energy reflections, larger discrepancies arise. This is likely due to either ODEON, the spatial measurement processing software, or the ambisonics microphone used to capture the spatial measurements. The accuracy of early energy data across both methods allows spatial impulse response measurements to be used in acoustic design, as a method of validating acoustic models or examining the changes in real-world reflections.
Assessing Northern Gulf of Mexico Sperm Whale’s (Physeter macrocephalus) seasonal patterns using passive acoustic monitoring
Authors: Ciampaglio Naomi M. , Sidorovskaia Natalia
Published: January 2025

Sperm whales (Physeter macrocephalus) show high sexual dimorphism and sexually regulated group structures. In the Northern Gulf of Mexico (NGoM), seasonal population demographics and the group structures have not been closely analyzed. Previous studies suggest that NGoM sperm whale population is dominated by females and juveniles, However, mature males have been known to have a presence as well. Utilizing Environmental Acoustic Recording System buoys, continuous acoustic recordings were acquired from June 2018 through June 2020. The buoys were deployed off the coast of Louisiana and the data were analyzed using a sperm whale click detector algorithm developed by our research team (Tiemann et al., 2011) as well as CABLE (Cachalot Automatic Body Length Estimator) software (Beslin et al., JASA 2018) for detecting sperm whale presence and estimating body lengths. Preliminary results showed that sperm whales are present all year with higher acoustic activity during the winter. The data also indicate a higher female and juvenile presence. Future investigations focus on understanding monthly and daily behavior of the NGoM sperm whale groups. The results will contribute to estimating NGoM sperm whale time budget. [This research was made possible in part by grants from The Gulf of Mexico Research Initiative and BOEM.]
Under-ice ambient noise and its masking effect on marine mammals in the Arctic
Authors: Shajahan Najeem , Halliday William D. , Insley Stephen
Published: January 2025

Climate change is changing the pattern of sea ice in the Arctic, which increases underwater ambient sound levels during the ice-covered season. The Arctic is home to multiple marine mammal species, even during the winter, which rely on the underwater acoustic environment for acoustic communication. Thus, climate change may be impacting the ability of these animals to communicate. Under-ice ambient noise is primarily generated by wind acting on the ice surface, rapid temperature changes, and impulsive transient signals resulting from ice cracking and ridging. To characterize under-ice ambient noise, acoustic data were collected from several locations in the western Canadian Arctic in this study. To determine the relationship between the received noise level, and wind speed and ice concentration, correlation analysis was used. For the detection and analysis of broadband transient events in the acoustic data, a spectrogram image processing approach was used. The spectral characteristics of transient events were generated using measurements and a random pulse train model. Furthermore, the wind and ice generated noise components were combined to predict the total ambient noise field in an ice-covered ocean using a wavenumber integral model. Finally, the model together with measurements was used to assess how ice-generated noise can cause communication masking in marine mammals such as ringed seals and bearded seals.
Program Manager's roundtable
Authors: Freeman Lauren
Published: January 2025

Join us for a one-hour virtual discussion with program managers from major US funding agencies including the Office of Naval Research and National Science Foundation, with experience funding programs in ocean acoustics, underwater acoustics, or sea-going research. Panelists will cover pre-planned questions on when and how to reach out to a program manager, how to write an effective planning letter and proposal, and current available opportunities for different career levels (fellowships for students, early career awards, and funding opportunities for ocean research/tech development); as well as comment on their own career paths. Questions will be collected in advance as well as taken during the session by the moderator. This is an opportunity to both learn what it takes to be a program manager, and strategies and tips for learning about funding opportunities and responding effectively.
Biomedical Acoustics Simon Lab (BASiL) tour at penn state university
Authors: Elliott Jacob C. , Rawnaque Ferdousi Sabera , Wood Grace M. , Simon Julianna C.
Published: January 2025

Welcome to the Biomedical Acoustics Simon Lab (BASiL)! Located in the newly constructed Engineering Collaborative Research and Education (ECoRE) building at Penn State, you can find the BASiLisks in their natural habitat. Our lab conducts a wide range of research at the intersection of diagnostic and therapeutic ultrasound, and as such, we have a large variety of equipment at our disposal for experimental use. In this video, we will give a tour of our brand new lab space, complete with demos of ultrasound field mapping, treatment monitoring, visualizing cavitation in cells, and more. In addition, the BASiLisks will give a brief overview of our new and exciting research developments. We are looking forward to showing you around our lab and hope that you can join us! [Ongoing work in the lab supported by NSF CAREER 1943937 and NIH R01EB032860.]
Lights, camera, vaporization: Coupling acoustics and microscopy to study acoustic droplet vaporization
Authors: Aliabouzar Mitra , Fabiilli Mario L.
Published: January 2025

Within the Department of Radiology at the University of Michigan, we have integrated mechanics, material science, and biomedical acoustics to develop ultrasound-assisted therapies and diagnostic techniques. What is our approach? Using ultrasound-responsive droplets. These droplets phase-transition from liquid to gas bubbles when exposed to ultrasound, a process termed acoustic droplet vaporization (ADV). We harness this transformation for a wide array of biomedical applications, such as delivering therapeutic payloads, modulating hydrogel properties, and characterizing material properties. In this video, we will demonstrate how to make monodisperse droplets using microfluidic techniques and prepare tissue-mimicking hydrogels containing these droplets for optical characterization. Resolving both the ADV-bubble response in an ultrasound field at clinically relevant frequencies, as well as the associated cellular and biological responses in real-time, requires high temporal and spatial resolution. To achieve this, we couple an ultra-high-speed camera (10 million frames per second) and time-lapse confocal fluorescence microcopy (1 frame per second). We will walk you through the process: aligning optical and ultrasound foci, coupling the transducer with samples on the microscope stage, aligning laser for high-intensity back illumination, synchronizing ultrasound and the camera, and finally, triggering ultrasound to generate ADV-bubbles
Computing cochlear pressure exposures from weapon systems using free-field to cochlea transfer functions
Authors: Mattson Courtney , Cozza Santino , Argo Theodore F. , Walilko Timothy J.
Published: January 2025

Overpressures generated by weapon systems can induce cochlear damage. Historically, the risk of injury has been assessed using free-field pressure waveforms. However, this approach fails to consider the modifying effects of human tissue and bone. To address this limitation, we developed transfer functions that convert free-field pressure signatures into approximations of the exposures that reach the cochlea. These transfer functions were derived from simultaneous free-field and cochlear pressure data recorded during shock tube exposures at varying peak pressures (1, 4, 8, and 12 psi) with and without hearing protection devices (HPDs). Our findings indicate that high frequencies (> ∼1000 Hz) are amplified by the human skull. Weapon system pressure signatures are processed using the transfer functions to approximate the intracochlear pressure differential between the scala vestibuli and scala tympani. The pressure-dependent transfer function is interpolated between the collected data based on the peak pressure of the incident waveform. The transformed data shows that the protective effects of HPDs vary based on the incident waveform. Protection tends to be effective at high frequencies, while low frequency pressures often exceed a 140 dB limit. Future studies may identify optimal HPDs for weapon operators that mitigate the harmful effects of blast exposures.
Computational ultrasound testing for non-destructive evaluation of multilayered structures: 3D modeling of longitudinal wave propagation signal responses
Authors: Tafkirte Mounir , Hamine Adil , Mesbah Hicham , Ettahiri Mohamed
Published: January 2025

Non-destructive evaluation (NDE) using ultrasonic imaging (UI) is essential for detecting defects in complex multilayered structures, which are commonly encountered in aerospace, automotive, and medical fields. A thorough understanding of material properties, wave propagation, and dispersion behavior is crucial for accurate defect detection. The Transfer Matrix Method (TMM) provides a comprehensive approach by modeling the entire UI process, including the control system, ultrasonic transmitter, wave propagation (both bulk and guided modes), and receiver response. This study focuses on predicting the backscattered ultrasonic signal during longitudinal wave propagation in a multilayer structure immersed in water, considering normal incidence and specific frequencies. TMM, employing a quadrupole formalism, integrates stress and velocities at layer boundaries and models the multilayer structure as a transfer matrix derived from individual layer matrices. This approach allows for the calculation of reflection coefficients across a wide frequency spectrum. TMM generates detailed distance-time and distance-frequency representations that illustrate the propagation of various longitudinal modes in configurations, such as plexiglass/water/glass under direct (PWG) and reverse (GWP) insonation. Comparisons between PWG and GWP distance-time planes may be affected by layer arrangement and properties, which influence the reflection coefficient, highlighting the system's sensitivity to layer order even with similar thicknesses and materials.
Geometry of 3D ray field and pulse propagation
Authors: Maltsev Nikolai E.
Published: January 2025

Field computations in ray approximation perform mapping in 6D space of ray parameters (a,b,t) and spatial coordinates (x,y,z), where (a,b,t) are launch angles in the source and t-eikonal. In the case of 2 spatial dimensions, mapping occurs in 4D space. This work investigates properties of such mappings, which allow a robust search of eigen-rays and modeling of pulse propagation
A low-cost ultrasonic absorption spectrometer for liquids
Authors: Crouse Michelle R. , Musiał Małgorzata , Pawlik Jacob , Bosworth Bryan , Orloff Nathan , Hagerstrom Aaron , Widegren Jason A. , Stelson Angela C. , Lirette Robert
Published: January 2025

Ultrasonic absorption spectroscopy can probe intermolecular interactions that inform research into processes for chemical engineering and pharmaceuticals. The only commercial ultrasonic spectrometer costs over one hundred thousand dollars, putting it out of reach for many institutions. We designed an inexpensive ultrasonic absorption spectrometer comprised of off-the-shelf components and parts from a rapid prototyping service. We employed the through-transmission method for measuring absorption, using thirty-one pulse measurements at varying distances. These measurements significantly improved measurement accuracy when compared to both a fixed path technique and the pulse-echo method that rely on only two measurements. We measured pure water to correct for diffraction effects and used repeated water measurements to propagate the uncertainty. To validate the spectrometer, we measured salt solutions, polyvinyl alcohols, and celluloses. We then compared the data to results obtained from a commercial spectrometer and they were well within the margin of error for both devices. Notably from these measurements, we observed a relaxation peak near 1MHz in scandium sulfate, which was only reported once before with the use of a resonance method. The system we present here offers an inexpensive alternative to a commercial ultrasonic absorption spectrometer that is accessible to university researchers and students.
Here’s my two cents… Low-cost, acoustically transparent containers allow quantification of cavitation energy in vitro
Authors: Dunn-Lawless Darcy M. , Collins Abigail , Coussios Constantin , Gray Michael
Published: January 2025

As cavitation-based therapies continue to enter the clinic, there is growing demand for methods to quantify the energy released by cavitating bubbles. Passive Acoustic Mapping (PAM) can reconstruct the energy and distribution of cavitation from multi-sensor recordings of bubble emissions, but its accuracy is impaired in vitro by the aberrating presence of a sample container between the cavitating media (nuclei/cells/tissues) and detectors. To our knowledge, the effects of these vessels on PAM have never been studied. Additionally, the typical need for sterility and a large number of samples makes low cost essential for sample containers in cavitation experiments. Here, we characterize the effects of common laboratory vessels in the range 3–14 MHz via an acoustic reciprocity experiment, then describe the design and testing of a novel container with improved acoustic transparency. The new device reduced worst-case magnitude and phase errors by 13.7 dB and 6.6 radians respectively, compared to ordinary 2 ml centrifuge tubes. We will also present quantitative measures of container effects on PAM energy measurement and localization. The new containers are manufactured from 100 micron polymer film via vacuum forming, are quick and easy to make in any shape in a normal laboratory, and cost US$0.02 each.
Training for fitting hearing protection devices
Authors: Murphy William J.
Published: January 2025

Hearing protection devices, particularly formable protectors, can be difficult to fit into the ear canal. Research in hearing protector fit testing has begun to focus on methods that can facilitate training for earplug users. The graph that has inspired my research was was created following a field study with oil and gas workers. The graph indicates the attenuation workers achieved before training versus after training. The graph has been used by other hearing science researchers.
Syllabus—More than just a piece of paper with course rules
Authors: Russell Daniel A.
Published: January 2025

I have never liked “syllabus day”—the first day of the semester when I'm supposed to go over the syllabus that students never read. Several years ago, I began writing course syllabi as newsletters, complete with color and images, and instead of discussing the syllabus in class I assign a quiz that requires students to read and engage with the syllabus content. When I saw the book “Syllabus: the Remarkable, Unremarkable Document That Changes Everything” by Germano and Nicholls (2020), I picked it up and read it, thinking it would give me a few ideas for making my syllabus documents even better. However, to my surprise, this book was much more than tips for getting students to read a boring course contract. Instead it challenged me to re-think how I design an entire semester-long course in light of what I want my students to have learned by the end of the semester and what I need to do in order to get them there. In this lightning-round talk I’ll summarize a few of the main takeaways that I have adopted since reading “Syllabus.”
Conducting an orchestra to reduce vehicle noise
Authors: Buday Ingrid
Published: January 2025

As with conducting an orchestra, directing the “sections” of vehicle noise pollution advocacy and hitting the right notes can be a challenge. Noise comes from a variety of sources and can be perceived differently by different people. And while the conductor tries to reconcile incompatible voices, the notes of regulation and legislation can be heard in the background, further complicating the piece. In Canada, No More Noise Toronto has initiated change at City Hall in a very short time. The grassroots campaign has been addressing high-volume vehicle noise by collecting data, critiquing existing processes, and encouraging Toronto citizens to participate, which has not been done previously. Using meters and crowdsourced methods, No More Noise Toronto seeks to understand noise “from the bedroom window,” which validates citizens’ noise reporting stories. Reviewing findings related to processes that lead to inaccurate data, barriers to involvement in the civic engagement process, and challenges created by frustration and feelings of apathy, we discuss actions taken and practices put into place as we’ve promoted a collaborative approach with stakeholders to find solutions and common ground in the shared goal of protecting the health of Toronto citizens.
Effects of a low-intensity two-talker speech masker on real-time spoken word recognition processes in children with normal hearing
Authors: Klein Kelsey
Published: January 2025

To comprehend speech, listeners much efficiently initiate lexical access (i.e., recognize word form), activate semantics (i.e., recognize word meaning), and suppress lexical competition. This study used a Visual World Paradigm eye-tracking task to examine how the presence of a low-intensity two-talker speech masker may disrupt these real-time processes in 19 10- to 12-year-old children with normal hearing. Each child completed the task (1) in quiet and (2) with the masker presented at a level individually determined to ensure high accuracy (mean SNR = 4.5 dB). Although accuracy was high while listening with the masker (mean accuracy >95%), children showed slower lexical access and semantic activation, relative to listening in quiet. Speed of semantic activation in the masker condition was not predicted by lexical access speed, suggesting that delayed semantic activation while listening to masked speech is not simply the result of delayed lexical access; rather, the presence of a two-talker speech masker may disrupt children’s ability to process word meaning. Participants also showed increased and prolonged lexical competition when listening with the masker, suggesting that a low-intensity masker may reduce children’s ability to resolve competition and commit fully to the target word, even when they ultimately recognize the word accurately.
The role of genre association in Sung Dialect categorization
Authors: Walter Maddy , Norris Sydney , Luk Sabrina , Maitinsky Marcell , Islam Jahurul , Gick Bryan
Published: January 2025

Genre-associated sociocultural cues may influence dialect recognition when listening to music. Previous work identifies genre-specific sociolects [Coupland, 2011, J. Socioling. 15]; singers make genre-dependent production changes [Gibson, 2019, U.Canterbury Diss.]; and accent is perceived with greater ease in song compared to speech [Mageau et al., 2019, Phonetica 76]. However, the role of genre associations in dialect categorization has not been sufficiently addressed. Our previous work suggests that genre identification may play a larger role in this than auditory speech cues [Walter et al., 2023, J. Acoust. Soc. Am. 154]. We investigate this further using a dialect-identification task with improved “spoken” stimuli. Participants heard sung clips (original instrumental-free vocals) and manipulated “spoken” clips (instrumental-free vocals, monotonized and rhythm-normalized) from counterbalanced genres with greater ease of vocal isolation: U.S. folk with some intra-genre dialect variation, and blues with strong associations to African American English [De Timmerman et al., 2024, J. Socioling. 28]. A superior vocal remover and lyrical transcripts were implemented. As predicted, in the sung context, participants identified genre-associated dialects consistently for both genres, but slightly more so for blues. Varied responses to the “spoken” context supports that listeners use genre information in musical dialect perception.
Evaluating the relationship between musical sophistication and melodic and harmonic expectations
Authors: Shorey Anya E. , Stilp Christian E.
Published: January 2025

Expectations are a fundamental and key factor in producing emotional responses to music; even musically untrained listeners demonstrate musical expectations. This is seen in priming tasks, in which musicians’ and nonmusicians’ categorizations of final tones are faster and/or more accurate when they are expected and related to a musical context (e.g., tonic) than when they are less related. Alternatively, in production tasks, participants sing/play what they expect to occur next in a sequence. This approach is limited to participants who can accurately generate and produce a response, usually those with some musical training. Both priming and production tasks typically compare musicians and nonmusicians without considering their musical backgrounds on a continuous scale or musical engagement beyond formal training. Here, participants completed an adapted melodic or harmonic production task (with multiple-choice responses, facilitating nonmusicians’ responses) and a priming task for the same sequences. Participants’ musical backgrounds freely varied. For production, related targets were predicted to be chosen more often than other targets, with increasing musical sophistication yielding more related responses. For priming, related targets were predicted to be categorized faster and more accurately than other targets, with increasing musical sophistication lessening this difference. Preliminary results offer partial support for these predictions.
Phase coherence of spontaneous otoacoustic emissions derived from a cochlear model
Authors: Vencovsky Vaclav , Bergevin Christopher
Published: January 2025

Spontaneous otoacoustic emissions (SOAEs) are commonly presented by averaging spectral magnitudes calculated in adjacent time segments of the recorded signal. To include the information carried by SOAE phase, Bergevin et al. [under preparation] proposed calculating the phase difference between adjacent time segments and then determine the vector strength to compute a measure of phase coherence. In stronger human SOAE peaks (magnitude >0 dB SPL), phase coherence plotted as a function of segment duration usually shows a maximum at around 100 ms, which shortens with increasing SOAE frequency above ∼2 kHz. Similar bell shaped dependencies coherence can be observed for simulated SOAEs from a nonlinear cochlear model composed of fluid-coupled oscillators, which simulate the transversal displacement of the basilar membrane (BM) [Vencovský et al. JASA, 2020]. The simulated BM displacement is amplified by feedback undamping force, which is transformed by a sigmoidal nonlinearity proportional to the second-order Boltzmann function. To evoke SOAEs, irregularities are added into the undamping feedback force and the model is driven by broad band noise applied into the eardrum (external noise) and into the undamping feedback force (internal noise). It appears that a combination of external and internal noise is needed to obtain the bell-shaped dependence of phase coherence on the segment duration similar to the one observed in human SOAEs. These results help guide how stochastic considerations must be included into active cochlear models.
Comparative study of higher modes of vibration in cantilever beams: Exact analytical analysis versus FEM analysis for accordion free reed acoustics
Authors: Volpatti Giovanni
Published: January 2025

This study delves into the critical role of higher vibration modes in cantilever beams, focusing on their significance for the acoustics of accordion free reeds. Through a comparative analysis, we explore exact analytical methods versus Finite Element Method (FEM) simulations to understand the vibrations not only parallel to the airflow direction but also perpendicular and torsional modes. Previous research has underscored the importance of these higher modes in shaping the timbre and influencing attack transients. Our findings reveal that while analytical solutions provide precise insights into fundamental vibrations, FEM offers comprehensive data on complex mode interactions. This dual approach enhances the understanding of reed dynamics, offering valuable insights for musical instrument design and acoustic optimization. By bridging analytical rigor with computational flexibility, this paper contributes to the nuanced study of musical timbre and transient behaviors, laying the groundwork for future innovations in reed instrument engineering.
Nondestructive evaluation of PLA cubes with varying cooling conditions
Authors: Pandit Partha Pratim , Keim Anna , Mirza Meher , Adepu Harshith Kumar , Kim Justin Yoosung , McClain Monique , Sotelo Luz D.
Published: January 2025

Fused Filament Fabrication (FFF) is one of the most extensively used additive manufacturing (AM) methods for the manufacturing of thermoplastic polymers. However, there are still many problems related to the quality of the printed parts. Most of the current research work for improving the part quality is limited to optimizing process parameters and using imaging techniques to analyze the part quality. Due to lack of consistency of quality across printers and printed parts, these efforts are insufficient to characterize and predict local material properties within the parts. Ultrasonic evaluation techniques are becoming increasingly recognized in assessing parts created by AM. In this work, Polylactic Acid (PLA) cubes were printed with varying fan activation layers. Ultrasonic and X-ray CT testing are employed to analyze and detect the controllable and observable deformation due to the change in in-situ cooling condition within the cubes. At the same time, mechanical properties and defect content were evaluated. It is important to understand the relationship between the fan cooling and mechanical properties so that effective fan cooling strategies can be deployed for consistent fabrication of higher quality parts across printers.
Modal analysis of a magnetorheological membrane
Authors: Aghamiri Seyyedmohammad , Sedaghati Ramin
Published: January 2025

Magnetorheological elastomers (MREs) are smart composite materials that can change their viscoelastic properties and provide actuation under application of an external magnetic field. In this study, a finite element method is developed in COMSOL Multiphysics to investigate the vibration characteristics of a membrane made of MREs under external applied magnetic field. The aim is to understand the effect of thickness, radius, and boundary conditions of the MRE membrane on its resonance frequencies and mode shapes under varied applied magnetic field. Results will offer valuable insight into how adaptive MRE-based acoustic membranes and metamaterials can be designed and tuned for broad-band noise suppression.