bluuebunny/crossref_metadata_2025 huggingface dataset:
High-performance computation toward large-scale underwater acoustics modelling
Authors: Kushida Noriyuki , Lin Ying-Tsong
Published: April 2023

The complex nature of the ocean has long presented a challenge for researchers in the field of oceanography, including in the area of underwater acoustics. As a result, significant efforts have been made to develop accurate numerical models to better understand and study the ocean. Established models such as Acoustic Toolbox and Range-dependent Acoustic Models have proven to be effective for modelling sound propagation. However, these models were designed to run on single-core computers, and there is potential to optimise their performance on modern systems. The use of General-purpose graphics processing units (GPGPUs) and Single Instruction/Multiple Data (SIMD) computing units is one way to achieve this optimization. In addition to improving the computational speed of established models, these optimized models can also contribute to implementing more sophisticated modelling approaches, such as broad-band modelling. In this study, we will discuss the optimized performance of established codes, particularly those based on parabolic equation methods (PE), and also discuss the results of advanced modelling techniques.
Big data to streamlined app: Nationwide traffic noise prediction
Authors: Cook Mylan R. , Gee Kent L. , Transtrum Mark K. , Lympany Shane V.
Published: April 2023

A vast amount of data can be processed using high-performance computing (HPC), but sometimes, the HPC hardware requirements are cost prohibitive. However, by using HPC to create reduced-order models that require much less processing power and data storage, the benefits of HPC can be realized for a wider range of users. For example, detailed traffic noise predictions can be made on small geographic scales using the US Federal Highway Administration’s Traffic Noise Model (TNM), but when considering a nationwide scale, TNM becomes infeasible for the typical user because of computational cost. Additionally, though calculating an annually averaged overall level may be within a user’s computational capacity, incorporating temporal and spectral variability increases complexity. Using HPC on hourly traffic counts at locations across the country together with published traffic trends and TNM equations, a streamlined app has been made to efficiently predict traffic noise at roads across the nation with temporal and spectral variability. This app, which presently requires less than 700 MB of stored geospatial data and models, incorporates user inputs such as location, time period, and frequency, and gives predicted spectral levels within seconds.
Project-based learning goes wrong: the trials, tribulations, and triumphs of managing first-year and fourth-year engineering projects
Authors: Lawless Martin S. , Gosselin Kathryn R.
Published: April 2023

Project-based learning (PBL) has many advantages for both students and instructors. The students are afforded the opportunity to work on self-driven, meaningful projects that model engineering problems they may see in their future careers. For the instructor, PBL emphasizes problem-solving strategies, requires students to learn relevant technical skills through self-study, underscores the importance of team work, and encourages student buy-in. However, PBL techniques present their own sorts of difficulties, especially when applied in large courses of 50 + students. For example, an instructor must strike a balance between fostering creativity and enthusiasm, while also keeping students on task and focused on the purpose of the project. Managing many small groups or a few large groups can be logistically challenging due to the sheer number of unique projects and students involved. This presentation will focus on two engineering courses, first-year introduction to engineering and fourth-year vibrations, in which project-based learning was employed with partial success. In these courses, there were logistic complications, issues with team dynamics, and problems with final presentations that can hopefully serve as good lessons (or warnings) for others interested in developing project-based courses.
A midshipman’s experience in leading the underwater acoustics and sonar class through a sound speed versus temperature experiment
Authors: Plosica Riley G. , Korman Murray S.
Published: April 2023

Oceanography and General Science majors are required to take Underwater Acoustics and Sonar during their junior or senior year at USNA. Our studio classroom has eight work stations where students measure sound speed in water. Author RGP was given the unique opportunity to lead her peers and present the sound speed demonstration in class. In this leadership role, it was necessary for RGP to motivate her fellow students as she demonstrated the pulse-echo experiment and emphasized its significance. First, students observed how the apparatus functioned and how to take measurements. Next, they broke into groups of four, and conducted the hands-on experiment as RGP communicated each step. Student pairs worked with the apparatus while two others observed. A learned skill during this process was managing the group in the observing role. This was a challenge. Peer-leadership experiences often required the leader to create an atmosphere of respect due to the lack of hierarchy that exists in the typical professor led classroom. Upon conclusion, RGP realized that there was success because students were able to submit accurate experimental measurements. While balancing an upbeat classroom with a constructive learning environment, RGP found the teaching experience instructional and her peer’s response gratifying.
Flanking noise transmission in a healthcare facility
Authors: Davenny Ben , Bliefnick Jay M.
Published: April 2023

Healthcare building constructions have some similarities and some differences compared with those of other building types. This presentation will examine door gasketing problems and perimeter sound isolation leaks found at an outpatient healthcare facility. The observations and test results for the problem conditions will be discussed along with our recommended solutions. Anecdotal feedback from the facility may be available by the time of the presentation.
A Martian sonic anemometer
Authors: White Robert D. , Banfield Don , Chaudhary Rishabh , Cheng Tim J. , Colaprete Anthony , Cook Amanda , Curran Tara , Dave Arwen , Huckaby Julia , Neeson Ian , Quigley Emmett , Rademacher Abraham , Steve Freidlay , White Bruce
Published: April 2023

On Mars, we have yet to fully quantify atmospheric turbulent transport [Banfield, JASA (2016)]. The key required instrument is a wind sensor that can resolve horizontal and vertical winds, and the perturbations associated with turbulent eddies. On the surface, 10–20Hz sampling and a sensitivity of 5 cm/s are required (McBean, 1972). Viking, Pathfinder, Curiosity, and Insight used hot film or hot wire anemometers that can be confused by radiative heating and sample at approximately 1 Hz. Sonic anemometry is an alternative high speed, high accuracy approach which uses differences in the acoustic time of flight to determine flow speed. However, operation on Mars can be challenging due to the low acoustic source strength and high attenuation in the thin (6––11 mbar) CO2 atmosphere, as well as large temperature variations (−100°C to 20°C). In this paper, we describe an instrument that addresses these challenges: a 3 axis ultrasonic anemometer using custom low impedance, wide band transducers, low noise electronics, and an optimized mechanical structure. With an earlier prototype in wind tunnel tests in 6 mbar CO2, we demonstrated resolution better than 10 cm/s, and an accuracy of 3% at flow speeds up to 12 m/s. Data from an instrument flight to 128 000 feet on a stratospheric balloon will be presented, and progress towards a flight qualifiable instrument will be described.
Modeling acoustic propagation on Mars
Authors: Gillier Martin , Petculescu Andi , Murdoch Naomi , Stott Alexander , Jacob Xavier , Mimoun David , Maurice Sylvestre
Published: April 2023

It is important to understand how the atmospheric conditions affect the propagation of sound waves on Mars, both for the study of the acoustic sources and of the atmosphere itself. As 3 microphones are already on Mars (2 on NASA/Perseverance and 1 on CNSA/Zhurong) and potentially more to come, a model of the propagation of sound in the Martian surface layer was needed. A first-principle acoustic attenuation model is used to quantify the excess attenuation of the Martian atmosphere. Thanks to inputs extracted from a global circulation model of Mars (the LMD Martian Climate Database), we are able to compare the magnitude of attenuation at different places and times, from 10 Hz to 20 kHz. Propagation effects are also considered by adapting a parabolic equation code to the Martian conditions. This accounts for strong temperature gradients near the surface, as well as gradients of wind speed. The acoustic reflection on the ground assumes a semi-porous medium. The turbulent fluctuations of temperature and wind speed are implemented using the frozen medium approach. The model shows that characteristics of sound waves propagation depend drastically on the local time. It provides a useful framework to interpret acoustic signal recorded on Mars. The model shows that characteristics of sound waves propagation depend drastically on the local time. It provides a useful framework to interpret acoustic signal recorded on Mars.
Acoustics on the planet Mars: Next steps, including sonic booms
Authors: Hetherington Lily R. , Kapcsos Joshua L. , Sparrow Victor W.
Published: April 2023

We congratulate the Perseverance rover team for measuring a dust devil and other sounds on Mars. This is a great achievement, and at the same time just a beginning. The acoustics community needs to apply itself to the situations that might come up when humans visit Mars. Work in the late 1990s and early 2000s set the stage for our knowledge of the outdoor sound environment of Mars. One next step will be to understand how shock waves and sonic booms will propagate on Mars. Because of the high atmospheric absorption, the shock structures of sonic booms are expected to differ on Mars compared to those on Earth. Some of the differences in potentially using a program like NASA’s PCBoom suite of tools will be discussed. Sonic booms have been used in the past to probe the atmosphere on Earth, and the prospects seem bright for successful similar applications on Mars. [Work supported by the Penn State College of Engineering.]
A time reversal metasurface for mimicking the cocktail party effect
Authors: Bourdeloux Constant , Lemoult Fabrice , Fink Mathias
Published: April 2023

The cocktail party effect is the capability to focus one's auditory attention on particular audio sources while ignoring other audio sources. We propose an experimental setup reproducing the cocktail party effect by designing a time dependent metasurface composed of independent active mirrors. Each active mirror is a programmable acoustical unit cell capable of hearing, computing, and emitting acoustic signals: each of them acts as a convolution filter. The proper metasurface temporal filters configuration allows us to establish acoustic communication between groups of individuals immersed in a noisy environment: a MU-MIMO acoustic system. The experiment consists in recording a set of Green's function between Ne emitters and Nj active mirrors, and a second set of Green's functions between the Nj active mirrors and Nr receivers. To increase the spatio-temporal degrees of freedom (Lemoult et al., PRL 103 2009), we place a forest of steel rods between the active mirrors, the emitters, and the receivers. These data are then used to compute each active mirror's temporal filter using time reversal properties to establish a predefined MU-MIMO configuration. The Ne emitters now emits simultaneously uncorrelated noises. These signals propagate through the disordered medium to the metasurface, then each active mirror hears, convolutes with his filter and emits another signal, which propagates back through the disordered medium towards the Nr receivers. In the end, we establish a correlation matrix by comparing emitted and received signals.
Sounds produced by subsonic ballistic flow
Authors: Beck Steven D. , Todd Norman W.
Published: April 2023

The sounds of passing subsonic ballistic projectiles are receiving more attention yet have limited acoustic characterization. Recent accounts include buzzing sound of a rifled bullet, and the whistling sounds of spherical projectiles produced by police firing non-lethal spherical rubber bullets, paintball, and war re-enactments using muskets. Modern recording equipment with multiple simultaneous channels and high dynamic range is now available to accurately capture subsonic ballistic flow sounds. Spherical projectiles 0.69 in. in diameter were launched from smooth bore replica muskets and high pressure paintball guns, and recorded on multiple microphones. Sounds of vortex shedding at predictable frequencies were produced using smooth spherical balls with no rotation, fired at velocities between 45 and 152 m/s (150–500 fps), and with Reynolds numbers below 3.75 × 105. The paintballs shed vortices in the 500–800 Hz range (with reported whoosh sounds); while faster musket balls shed vortices in the 2000–2500 Hz range (with reported whistling sounds). Our interest originally arose from historical reports that Erastus “Deaf” Smith, a hero of the Texas Revolution, could not hear musket balls that passed near him; and recent medical speculation that he had a 2000–3000 Hz notch in his hearing spectrum.
Multi-mode instability interactions in twin jet configurations
Authors: Karnam Aatresh , Saleem Mohammad , Gutmark Ephraim
Published: April 2023

Twin jet configurations are prone to a wide range of interactions due to flow instabilities driven by jet self-excitation and cross-excitation of one jet on another. These instability modes and associated phases are sensitive to many parameters chief among which is the exit profile of the nozzle. Extensive studies on Twin Circular nozzles and Large Aspect Ratio (AR) Twin rectangular nozzles have shown various mode coupling but, not much is known about twin jets with moderate aspect ratios (AR < 3). This study aims to understand the effect of the exit nozzle geometry on the generation of flow instabilities by comparing a Twin Rectangular nozzle (AR 2) to a Twin Square nozzle (AR 1) with identical design parameters through experimental analysis. High speed Schlieren imaging is coupled with Particle Image Velocimetry (PIV) to explore both qualitative (internal shock cell structure) and quantitative aspects (flow vorticity and turbulence) of these jets. Near field and far field acoustics are also studied to provide a wholistic understanding of the effect of mode coupling exhibited by these jets. Generation and propagation mechanisms of multi-mode instabilities which effect both nozzle orientations are also studied through Spatial and Temporal Fourier analysis.
Effect of internal geometry on supersonic jet noise
Authors: Gautam Kaurab , Karnam Aatresh , Saleem Mohammad , Gutmark Ephraim
Published: April 2023

The current study discusses the experimental results of the effect of two types of nozzle internal geometries. The first configuration uses a common inlet that diverges the flow into two separate channels that feed twin rectangular nozzles, and the second configuration has the plug flow type system with twin rectangular nozzles drawing air from a common plenum. The nozzles are converging diverging type with design Mach number of 1.5. Flow conditions encompassing overexpanded, design, and underexpanded conditions are tested with acoustic data collected in the farfield and nearfield domains. High-speed Schlieren imaging is used to visualize the effect of internal geometry on the development of the jet shock cell structure and twin jet interaction. The variations in the Overall Sound Pressure Level (OASPL), frequency spectra, and jet phase coupling are used to quantify the effect of the internal geometries. This is supplemented by Spectral Proper Orthogonal Decomposition (SPOD) results obtained from the Schlieren images to quantify the variations in flow development.
Effects of age and hearing loss on talker identification and talker change detection
Authors: Best Virginia , Ahlstrom Jayne B. , Mason Christine R. , Perrachione Tyler K. , Kidd Gerald , Dubno Judy R.
Published: April 2023

While the detrimental effects of age and hearing loss on word recognition and speech comprehension are well-established, surprisingly little is known about how these factors affect the ability to extract talker-related information from speech. Here, we describe two studies that used different behavioral tasks to address this question. In the first study (Talker Identification), listeners were trained to identify talkers by the sound of their voice, and then tested on their ability to identify those talkers in quiet or in the presence of background noise or competing speech. In the second study (Talker Change Detection), explicit talker identification was not required, but instead listeners detected if a change in talker had occurred within a sequence of words. In both studies, listeners were recruited in four groups to include younger/older ages and normal/impaired hearing. In both studies, we found that age and hearing loss had independent effects on performance. We argue that a reduced ability to make use of talker-related information in speech may contribute to the difficulty encountered by older listeners and listeners with hearing loss, when communicating in group situations.
Utilizing auditory emotion bio-markers, the underpinning of emotion perception improvement in cochlear implant users
Authors: Paquette Sebastien , Gouin Samir , Lehmann Alexandre
Published: April 2023

Cochlear implants (CI) have had tremendous success restoring a sense of hearing in the deaf. However, even after months of intensive rehabilitation, many CI users struggle with appreciating emotive tones in speech and music despite good speech comprehension. Failure to perceive emotional expression can result in maladjusted social behaviour, leading to detrimental socio-economic consequences. Recent advances in automated pattern identification of neuroimaging data can bring empirical support to developing training programs for emotion perception rehabilitation in CI users. We used a machine-learning approach to identify emotion-processing bio-markers in high-density electroencephalograms collected from CI users (22) and matched normal-hearing controls (22). Participants’ brain responses elicited by short musical and vocal emotional (happy, sad, and neutral) stimuli were used to train an algorithm to help identify, in each group, the pattern of brain responses that can best predict the presented emotion. Using this approach, we were able to confirm the presence of emotion-specific patterns of brain activity in CI users despite their reported emotion perception deficit. Identifying these patterns brings forward support for implementing a rehabilitation program for emotion perception for this population; if an algorithm can differentiate aurally presented emotions, perhaps CI users can learn to discriminate emotions.
Lamb waves in thermoplastic polymer plates: An application to monitoring
Authors: Spytek Jakub , Prada Claire , Ing Ros-Kiri , de Rosny Julien
Published: April 2023

Thin thermoplastic polymer components are widely used in different fields of engineering, including high-technology industries such as automotive or energy. Due to the rapid technological development in these industries, there is an increased demand for polymer components to achieve advanced functionalities, such as the continuous monitoring of their structural health. In this work, we propose to take advantage of elastic guided waves, which are both emitted and measured using arrays of transducers integrated within the structure. This application requires first investigating the Lamb waves in these attenuating and heterogeneous materials. To that end, we estimate the dispersion curves of Lamb waves using a laser vibrometer. A transversely isotropic material model and a fitting algorithm allow for estimating the elastic parameters of the specimens. Then, for each mode, the frequency-dependent attenuation is evaluated. Finally using both theoretical models and experimental analysis, we evaluate the sensitivity of the guided waves to asses various structural changes in the thermoplastic polymer components such as temperature or the presence of contaminants.
Declarative or declarative question?—On the acoustics of English prosody of Hong Kong trilingual children with autism spectrum disorder
Authors: Wang Bruce Xiao , Chen Si , Zhou Fang , Liu Jiang , Xiao Cheng
Published: April 2023

The current study investigated the production of English prosody (i.e., focus marking) of trilingual Cantonese children with autism spectrum disorder (ASD) and their typically developing (TD) peers (i.e., Cantonese and American English children without ASD) using declarative questions. Speech materials were segmented at word and syllable levels, and word duration, f0, f0 range and intensity were extracted. Acoustic data were fitted using linear mixed-effects models with different explanatory variables followed by a likelihood ratio test. Between group comparison showed that the ASD group had significantly more fluctuating f0 range in post-focus words than the TD groups, which is likely to be an indication of hypercorrection, i.e., over-application of perceived prosodic pattern in English declarative questions. Within groups, the Cantonese children showed different patterns to the English children in terms of the interaction between the acoustic measures and on-focus expansion and post-focus compression. The Cantonese ASD group showed some degree of post-focus compression in terms of duration and mean f0, while the Cantonese TD group only had such pattern in terms of mean f0. The English TD group had a tendency of on-focus expansion in terms of duration and f0 range, but post-focus words showed significantly higher mean f0 than the pre- and on-focus ones, probably due to the question intonation.
Age and sex effects on sound change: One size does not fit all
Authors: Kpogo Felix
Published: April 2023

This study examines whether speaker age and sex predict production of Advanced Tongue Root (ATR) vowel harmony by urban Twi (Niger-Congo, Kwa) speakers in Ghana. Traditional descriptions of the ATR harmony system state that [-ATR] /a/ is phonetically realized as [ + ATR] [æ] before [ + ATR] vowels /i, u, o/ and palatal segments. However, recent research indicates that this description is no longer accurate for all Twi speakers: in contrast to suburban speakers, most urban speakers raise and front [æ] to [e], impinging on phonemic /e/, before /i, u/ and palatal segments (Kpogo, 2021). This pattern suggests a possible sound change (i.e., vowel merger) if suburban speakers are taken to represent a conservative variety of Twi. To explore the source of this innovation among urban speakers, variation in production across speaker age and sex was investigated. Preliminary acoustic data from a picture-naming task suggests that both factors are predictive of the innovative production pattern. Adolescents and younger adults, but not older adults, raise and front [æ] to [e], implicating the younger generation as leading this linguistic innovation. Additional findings suggest that men, but not women, are leading the innovation, a finding inconsistent with the overwhelming generalization that female speakers lead linguistic innovations.
Effects of utterance length on word and phrase durations
Authors: Kim Seung-Eun , Tilsen Sam
Published: April 2023

This study examined the effects of utterance length on word and phrase durations to investigate how the planned length of an utterance influences the rate of speech. An experiment was conducted in which the visual stimuli cued the production of sentences with one, two, or three subject noun phrases (NPs)—e.g., “Nine green rhinos and eight red weasels and eight blue llamas live in the zoo.” In addition, a novel, delayed stimuli condition was tested in which the visual stimuli that cued non-initial NPs (“eight red weasels and eight blue llamas”) were presented after participants started production, and thus sentence length changed after utterance initiation. Word and NP durations were analyzed. NP durations were longer in sentences with more NPs, and moreover, durational increases were primarily observed in the rightmost words of the NPs. These findings are important first because they show that the previously observed effects of number of words on word durations extend to phrases, and second because they show that phrase duration effects are localized to phrase ends. When the utterance length changed after the start of production, participants lengthened the end of the initial NP and the following conjunction to plan for the newly presented NPs.
Acoustic variability of examiners’ productions in language assessment
Authors: Ancel Elizabeth , Finestack Lizbeth , Munson Benjamin
Published: April 2023

Speech-Language Pathologists and other professionals administer assessments to determine whether children have communication disorders. Although these assessments specify procedures to ensure comparable administration across examiners, there are still individual factors that are unaccounted for. A commonly used measure in assessment is sentence repetition, in which a child repeats a live-voice production of a sentence. Sentence repetition tasks necessarily reflect the unique prosody used by experimenters, and in particular their rate of speech and f0 patterns. This study investigates examiners’ rate and f0 variation as they administer a sentence repetition task in order to quantify variability within and between the examiners. To do this, we analyzed recordings of 25 different speakers administering the Sentence Repetition subtest of the Clinical Evaluation of Language Fundamentals (CELF) to children aged 3 through 10 years old. For each production of a sentence, we measured the mean pitch, pitch range, and speaking rate. The results indicate the extent to which each examiner varied these prosodic features based on the assessment item and the age of the child undergoing the assessment. This variability is compared across examiners to capture a possible point of inconsistency that may affect children’s performance on these assessment tasks.
The effect of phrasing, speech rate, and information structure on tonal coarticulation in spontaneous Cantonese
Authors: Gao Xin , Liberman Mark
Published: April 2023

Pre-low raising is a tone coarticulation phenomenon in which the pitch of a high-tone syllable is higher before a low tone than before a high tone. Lee and Xu (2016) found that speech rate influences the degree of this pre-low raising, in recordings of read disyllables in carrier phrases. In the present study, we examine this phenomenon in spontaneous Hong Kong Cantonese using the CantoMap Map Task dataset (Winterstein et al., 2020), also exploring the possibility of similar effects on the realization of other tones. Along with speech rate, we also consider the possible effects on thistonal dissimilation of phrasing (relations between a syllable and the subsequent syllable), the relative location of a syllable in a sentence, and information structure (the role of the word in the map task interaction). We expect that all of these factors will influence tonal coarticulation in general, and pre-low raising in particular.
Pitch elevation and vocal loudness are related to swallowing safety. A proposal to improve their performance
Authors: Castillo-Allendes Adrián , Hunter Eric J.
Published: April 2023

The ability to perform high-pitched and loud tasks have been associated with lower risks of penetration and aspiration in people with oropharyngeal dysphagia (OD). Previous studies suggest that these two vocal tasks may improve swallowing-related kinematics; laryngeal elevation and glottic closure. This study aims to identify which types of vocal exercises can maximize pitch elevation and vocal loudness. This ongoing project involved five subjects with OD who were asked to perform three vocal exercises: effortful pitch glide, straw phonation, and water resistance therapy (WRT). Fundamental frequency (fo) and maximum dB SLP were obtained during their performance; moreover, the vocal effort was quantified using a Borg CR100 scale. Descriptive statistics were used to characterize the differences between the three proposed exercises. WRT was the exercise that allowed toobtain higher pitch elevation values with less vocal effort (median fo = 603Hz), over EPG(594 Hz), and then straw phonation (512 Hz). Furthermore, EPG allowed reaching a higher vocal loudness during its performance. These preliminary results indicate that WRT could be a potential therapeutic adjunct to improve swallowing-related biomechanics. Further details will be presented. Future studies could incorporate accelerometry to obtain more accurate fo and dB SPL measures during vocal exercise performance.
Acoustics of the creaky phonations in Yateé Zapotec
Authors: Chai Yuan , Fernández Adrian , Mendez Briseida
Published: April 2023

Yateé Zapotec (YZ) is a variety of Zapotec spoken in San Francisco Yateé, Oaxaca, Mexico. The language has three phonation types: modal, checked, and rearticulated. Checked and rearticulated phonations both involve glottalization realized on vowels but differ in the phasing of the glottalization in vowels. Checked phonation has late-phased glottalization whereas rearticulated phonation is characterized by mid-phased glottalization. Previous studies on the phonetics of Zapotec phonations seldom compare the phonations in the time domain. In this study, we compare the spectral tilt, degree of noise, amplitude of voicing, and duration of the three phonations over the time course of vowels. Using multi-dimensional scaling analysis, we also find that the amplitude dip in the middle of the vowels (induced by glottalization) differentiates rearticulated vowels from modal and checked vowels, while the shorter duration differentiates checked vowels from modal and rearticulated vowels. We conclude that in YZ, mid-phased glottalization is the defining feature of rearticulated phonation whereas duration is the defining feature of checked vowels. Future studies can test whether YZ listeners are also more sensitive to amplitude dip and short duration when perceiving rearticulated and checked vowels.
Acoustic properties of subtypes of creaky voice
Authors: Keating Patricia A. , Garellek Marc , Kreiman Jody , Chai Yuan
Published: April 2023

“Creaky voice” is a term that covers multiple kinds of voicing, and there is no single defining acoustic property shared by all subtypes of creaky voice. Here we explore the distinct characteristics of each subtype. We identify three main properties of creaky voice: low f0, irregular f0, and constricted glottis (as shown by electroglottography). Prototypical creaky voice has all of these properties; other subtypes are characterized by different subsets of properties. We will describe, with reference to previous literature, multiply-pulsed creak (a special case of irregular f0, along with low f0), open-glottis creak (low and often irregular f0, but unconstricted glottis), vocal fry (low but regular f0, constricted glottis), and creak with such irregular pulsing that no f0 can be recovered. Building on our previous work [Keating et al. 2015 Proc. ICPhS], we show how various acoustic measures pattern for each subtype. Results from parametric speech synthesis provide support for our acoustic observations.
Imaging ocean water columns by acoustic contrast reflection signals in existing marine seismic data
Authors: Zhang Likun
Published: April 2023

Marine seismic surveys conducted for oil and gas exploration use a source-receiver system consisting of airgun sources and hydrophone receiver arrays. The collected data were commonly used to image subsurface beneath the seafloor. The surveys had also collected signals of acoustic reflections from ocean water columns due to acoustic impedance contrast by temperature and salinity. These signals can be processed to provide high-resolution images of the water-column structures such as eddies and internal waves, forming a discipline termed as seismic oceanography in the literature. Acoustic contrast reflection signals in a three-dimensional seismic survey, collected by multiple parallel receiver arrays, can even be used to explore movements of water columns {see our recent study in [Zou,etal., Ocean Sci. 17(4), 1053–1066 (2021)]}. Nevertheless, because of the low acoustic impedance contrast in oceans, these water-column reflection signals are extremely weak, e.g., about 2–3 orders weaker than the seafloor reflections. Meanwhile, these signals consist of acoustic multipath features that require an appropriate filtering of the signals (see our recent study in the study by Zou and Zhang [JASA 150(5), 3852–3860 (2021)]. Understanding of the signal features and appropriate applications of acoustic signal processing methods are inspired to improve the imaging quality.
Near-field acoustic holography for underwater moving surfaces
Authors: Valdivia Nicolas P.
Published: April 2023

Near-field acoustic holography has been the standard technique to accurately image static structure vibration from nearby acoustic pressure measurements. The classical application bases the method on the stable solution of an integral surface representation of the acoustic pressure. In this work, we will be concerned with the extension of NAH to image a vibrating structure moving underwater. In an underwater medium, even at slow speeds, the action between the flow and structure produces many radiation sources that could severely limit the accuracy of the integral surface representation used for static NAH. Using the Lighthill acoustic analogy, we use an integral surface representation for the structure’s radiated sound and a quadrupole source that models the corresponding flow-induced sound. Finally, we will justify the validity of the proposed method for COMSOL numerically generated pressure data that results from the internal excitation of a cylindrical structure moving over an underwater medium. This work has been supported by the Office of Naval Research.
Experimental formation of the 2D hologram of high-frequency source by a vector receiver in shallow water
Authors: Pereselkov Sergey A. , Kuz'kin Venedikt , Tkachenko Sergey , Ladykin Nikolai , Sotnikov Dmitry , Pereselkov Alexey
Published: April 2023

The results of a high-frequency experimental formation of the 2D hologram of a moving noise source using a cylindrical small-sized vector-scalar antenna are presented. The purpose of the experiment is to test the efficiency of the interferometric method in the high-frequencydomain (1–15 kHz) for noise source localization. The experiment was carried out in a shallow water area with a water layer depth 87 m. The source localization method is based on processing of its interferogram. The 2D-FT (2D Fourier Transformation) of the interferogram is hologram of moving source. 2D hologram allows to coherently accumulate the sound intensity of the interferogram in a small area as focal spots in hologram domain. The focal spots localization in hologram domain depends upon the source range, velocity, and motion direction. The time dependences of source range, its velocity and motion direction are estimated on based of holographic signal processing. The comparative analysis of theoretical dependences and experimental data is carried out. [This study was supported by RFBR 19-29-06075, МК-4846.2022.4.]
Perspective on publishing acoustic data: Case studies, limitations, and solutions
Authors: Way Evelyn
Published: April 2023

There are many considerations for manufacturers publishing acoustic data. Varied audiences, test variability, building codes, liability, and convoluted standard test methods put competing interests on product testing and data publishing. Discussion will use case studies of floor/ceiling isolation data to provide clarity and insight to help the practitioner navigate a complicated data landscape.
Challenges in tuning the measurement performance of a reverberation chamber
Authors: Glean Aldo , Gatland II Stanley D. , Lilly Jerry G.
Published: April 2023

Round-robin testing determined that a high degree of reproducibility exists between laboratories that conduct sound absorption measurements in accordance with ASTM C423. Factors that include room dimension, source location and diffuser type have been identified as sources for differences in measurement results. Such lab to lab testing variation presents a challenge when reverberation chambers are replaced with new design and construction features that are not identical. An iterative process is required to produce measurements that match historical results. The presentation will describe the design approach utilized to construct a new reverberation room with different dimensions, diffuser types and materials. Experimental data will be presented showing the results of modifications made to the chamber after achieving initial qualification metrics. The iterative process provided an opportunity to study the impact of diffuser type and surface area and other properties on reducing the performance gap between the two reverberation rooms.
Repeatability in fan sound ratings: Challenges faced in a certification program
Authors: Mathson Tim
Published: April 2023

The Air Movement and Control Association International (AMCA International) maintains a certified ratings program for published air and sound performance for fans. Sound test results can come from AMCA 300 reverberant room testing but are also accepted from manufacturers’ accredited labs using other international test standards covering in-duct, enveloping surface, and sound intensity test methods. Observed repeatability between these test methods and labs will be discussed. AMCA 301 covers sound calculation methods, including extrapolation to non-tested sizes and speeds. Requirements and practical recommendations for this conversion will be discussed. Surveillance for the program comes through periodic check tests on manufacturers’ products. The check test process provides an overall view of measurement and calculation variance, as well as inevitable manufacturing tolerances and their impact on sound. Finally, the results of round robin testing conducted on centrifugal, tube axial, and vane axial fans at various accredited sound labs will be reviewed.
Forty-plus years of Navy research by the dolphin BLU
Authors: Finneran James
Published: April 2023

The dolphin “BLU” has had an amazing career spanning over 40 years of Navy fleet support and scientific research. Her research career began in the late 1970s with Sam Ridgway, studying lung-collapse and intramuscular nitrogen levels in diving dolphins. For the next several decades, she served with the Navy’s Fleet mine-hunting systems and was deployed to locations all over the world. In 2003, at age 37, BLU returned to research, where her intelligence and unflappable demeaner quickly made her a star. Over the next few years she participated in a number of studies using behavioral and auditory evoked potential techniques to measure hearing thresholds and temporary threshold shift (TTS). TTS data from BLU were instrumental in developing marine mammal noise exposure regulatory guidelines. After having a calf in 2007, she became a working mom by beaching and transporting to the test pool each day, then returning to her calf at the conclusion of the session. BLU would go on to participate in a number of studies involving directional hearing, tactile sensitivity, and biosonar beam patterns. This talk will review BLU’s career with the Navy and highlight her research contributions that have resulted in over 35 peer-reviewed journal articles.
Magnetic resonance elastography of the brain: Recent advances
Authors: Johnson Curtis L.
Published: April 2023

Magnetic resonance elastography (MRE) is an imaging technique for generating maps of quantitative tissue mechanical properties. Mechanical properties of the brain offer sensitive new biomarkers for diagnosing neurological conditions and individual differences in brain health that support cognitive functioning. However, the mechanical complexity of the brain—e.g., heterogeneity in space and scale, frequency- and direction-dependent behavior, skull encasement—require advanced MRE techniques to reliably and accurately map brain tissue properties. We will discuss recent developments in MRE imaging and inversion methods and experiments aimed at more completely estimating brain properties. This includes approaches for determining mechanical anisotropy in white matter tracts comprising aligned axonal fiber bundles from rich acoustic wavefields. And new experiments capturing time-dependent variation in properties and the relationships to cerebral blood flow. Such advances increase the capabilities of MRE as an imaging tool and concomitantly enrich our understanding of the physiological bases of in vivo brain mechanical properties.
Homogeneity versus inhomogeneity in muscle elastography
Authors: Nammari Lara , Klatt Dieter , Royston Thomas
Published: April 2023

The hierarchal microstructure and arrangement of skeletal muscle fibers results in both anisotropy and inhomogeneity. Most elastography reconstruction methods assume homogeneity and many also assume isotropy. In this computational (finite element) and experimental (MR) elastography study we investigate the impact of assuming homogeneity as muscle architecture dimensions and property differences are varied. This analysis also takes into consideration the inherent anisotropy (transverse isotropy) created by homogenization of the fiber structure, and the added complication ofnonhomogeneous (pre-stress) boundary conditions. Specifically, the computational harmonic analysis uses a parametric sweep across 200 Hz to 2000Hz applied to 4-, 40- and 400-fiber models with the aligned fiber cross-sectional area fixed (reduced fiber diameter as fiber count increases) and comprising 50% of the circular cross-sectional area in the fixed diameter cylindrical phantom. Fiber elastic moduli two to five times that of connective tissue are considered. This phantom also undergoes tensile axial pre-loading simultaneous to elastography studies. Predicted results are compared to a homogeneous transverse isotropic model that is reached in the limit as the fiber count increases to infinity while still summing to 50% of the cross-sectional area. Selected cases, such as the 4-fiber model are also evaluated experimentally using MR elastography.
Uniaxial prestress and waveguide effects on estimates of the complex shear modulus using magnetic resonance elastography in a transverse isotropic muscle phantom and excised muscle
Authors: Salehabadi Melika , Crutison Joseph , Nammari Lara , Klatt Dieter , Royston Thomas
Published: April 2023

Tensile prestress is inherent to the functional role of some biological tissues currently being studied using elastography, such as skeletal and cardiac muscle, arterial walls, and the cornea. Therefore, the impact of prestress coupled with waveguide effects due to small dimensions in one or more directions needs to be better understood. An experimental configuration is designed, fabricated and experimentally tested using magnetic resonance elastography (MRE). Cylindrically-shaped isotropic and transversely isotropic phantoms, as well as the excised cat soleus muscle are statically stretched along their main axis to specific prestrain levels while simultaneously conducting MRE measurements that enable synchronous motion-encoding in all three dimensions (polarization directions). In the case of the excised cat soleus, diffusion tensor imaging is also performed to enable a co-registered mapping of fiber structure. Guided by analytical models and numerical finite element simulations, experimental measurements are post-processed to obtain an estimate of the complex (viscoelastic) shear modulus as a function of prestress level and frequency of vibratory motion.
Real-time transcranial mapping in non-human primates and human subjects during opening of the blood-brain barrier
Authors: Konofagou Elisa
Published: April 2023

Opening of the blood-brain barrier (BBB) with focused ultrasound and microbubbles has been shown repeatedly in several preclinical disease models and clinical studies. Transcranial 2D mapping of the cavitation mechanism responsible for BBB opening is however challenging in primate brains due to the skull thickness. A real-time cavitation mapping system will be presented that can transcranially map the cavitation occurrence and dose in real time throughout the BBB opening procedure in Alzheimer’s disease (AD) adult and diffuse intrinsic pontine glioma (DIPG) pediatric patients. Passive acoustic mapping (PAM) with coherence factor (CF) correction is used to passively map the microbubble activity within the brain. Compared to passive cavitation detection (PCD), multi-element CF-PAM allows us to determine the exact location of the BBB opening without the need of contrast-enhanced MRI. An open-architecture ultrasound imager (Vantage, Verasonics, Redmond, WA) with a P4-2 (ATL, Philips) is used to provide the best tradeoff between transcranial propagation, spatial resolution and depth penetration. The system is first optimized in targeting the putamen during BBB opening in non-human primates followed by feasibility in the prefrontal cortex in AD and the pons in DIPG patients, achieving feedback rates of 2 Hz during the clinical procedures.
Transcranial cavitation mapping of blood–brain barrier opening regions in Alzheimer’s disease patients using a neuronavigation-guided focused ultrasound system
Authors: Bae Sua , Pouliopoulos Antonios , Ji Robin , Liu Keyu , Jiménez-Gambín Sergio , Yousefian Omid , Kokossis Danae , Honig Lawrence , Konofagou Elisa
Published: April 2023

We present real-time cavitation monitoring and mapping in a clinical trial for blood-brain barrier (BBB) opening in Alzheimer’s disease (AD) patients using a neuronavigation-guided focused ultrasound (FUS) system. Six AD patients (N = 6, age = 68.5 ± 9.5) were sonicated at the right prefrontal lobe with a single-element FUS transducer (PNP = 0.2 MPa, fc = 0.25 MHz, pulse length = 10 ms, PRF = 2 Hz, duration = 2 min) with the microbubble administration (Definity). We performed passive cavitation detection (PCD) using a single-element hydrophone (N = 4), and passive acoustic mapping (PAM) with a 64-element phased array transducer (N = 2). Five patients showed successful BBB opening (volume = 654 ± 394 mm3) on day0, and closure on day3, confirmed by contrast-enhanced T1-weighted MRI, while one patient served as a negative BBB opening case due to the insufficient microbubble administration. Ultra-harmonic cavitation dose (CD) correlated with the opening volume (R2 = 0.66, N = 4), but harmonic and broadband CDs showed a relatively poor correlation (R2 = 0.06 and 0.33). Cavitation maps (N = 2) showed a spatial distribution of acoustic energy that roughly coincided with the respective BBB opening location. We thus demonstrated the successful BBB opening and cavitation monitoring with the neuronavigation-guided system that allowed for a cost-effective procedure compared to the MR-guided approaches. The PCD and PAM showed promising results for potentially predicting the BBB opening volume and location found in MRI.