bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the Coastal Acoustic Buoy for offshore wind for real time mitigation of North Atlantic right whales
Authors: Palmer Kaitlin , Turner Jesse , Tabbutt Sam , Gillespie Douglas , Thompson Jessica , King Paul , Wood Jason
Published: November 2021

A recent Incidental Harassment Authorization requires a 10 km zone to be monitored with passive acoustics before and during pile driving. SMRU Consulting has built the Coastal Acoustic Buoy for Offshore Wind (CABOW) to address this need. Each CABOW consists of: a bottom lander with three hydrophones; data acquisition system; and onboard computer running PAMGuard. The CABOW detects potential calls and relays clips to a base station for classification, bearing estimation, and validation. Bench testing characterized detector performance and measured bearing accuracy as a function of SNR. Field trials used playbacks of real and simulated right whale upcalls to evaluate the detection probability with respect to the range and signal excess of the call; estimate bearing accuracy; and test the range and stability of the radio communications. Field trials indicated a maximum detection range of 4–12 km under high and very low noise levels, respectively. Finally, we used a simulation to compare true and false alarm rates of the CABOW to an equivalent single sensor system for monitoring a fixed area. Simulations show that incorporating bearings to calling animals could provide a substantial improvement in false alarm rates relative to single sensors if properly placed with respect to potential noise sources.
A study of the vocal behavior of adult bald eagles during breeding and chick-rearing
Authors: McGee Joann , Nelson Peggy , Ponder Julia B. , Feist Christopher , Milliren Christopher , Walsh Edward J.
Published: November 2021

Previous efforts to characterize the spectral and temporal properties of calls contained in the vocal repertoires of adult bald and golden eagles, Haliaeetus leucocephalus and Aquila chrysaetos, respectively, led to the generation of a catalog of call types with distinguishing acoustic properties (McGee et al., 2019). Calls analyzed as part of that investigation represent vocal activity produced by captive, adult birds, some of which are long-standing residents of the Raptor Center at the University of Minnesota, as well as temporary residents undergoing rehabilitation from injury. Here, we compare the spectral and temporal properties of those calls with calls produced by free-ranging adult bald eagles recorded along with video during nest preparation, courtship, egg incubation and chick-rearing activities at nest sites monitored by the Raptor Resource Project. One goal of this project is to determine if the vocal repertoire of bald eagles studied in captivity is representative of that of free-ranging wild eagles. Another goal is to determine the extent to which spectrotemporal characteristics of calls recorded from captive and free-ranging birds overlap. Findings from this study will provide guidance in ongoing efforts to develop acoustic alerting signals designed to minimize the risk of eagle-wind turbine collisions.
Combined acoustical and seismic studies of Axial Seamount
Authors: Wilcock William S.
Published: November 2021

The NSF Ocean Observatories Initiatives Regional Cabled Array at Axial Seamount provides a remarkable facility for sustained studies of an active submarine volcano. A local seismic network supports a real-time earthquake catalog and hydrophones monitor sounds in the water column. In April 2015, Axial Seamount erupted shortly after the cabled observatory came on line. The seismic record of brittle deformation in the summit caldera during the eruption is complemented by acoustic observations that tracked a dike propagating along the north rift using T phases and recorded both impulsive and continuous sound sources on the seafloor at the sites of erupting lava. Seafloor pressure gauges are presently documenting the reinflation of the volcano towards its next eruption and these geodetic studies would be enhanced by deploying a transponder network to support horizontal ranging. The availability of real-time data to detect and localize future eruptions will enable effective autonomous and ship-based responses to study how hydrothermal systems and their chemosynthetic biological communities respond to eruptions. The seismic and acoustic networks could also support studies of fin and blue whales to understand whether their distribution is modulated by the enhanced productivity associated with the presence of a hydrothermally active seamount.
Soundscape around the Dongsha reef atoll at the northern South China Sea
Authors: Ma Barry B. , Chiu Linus Y.-S.
Published: November 2021

The Dongsha reef atoll is on the direct path of trans-basin large internal solitary waves (ISWs) at the northern South China Sea. The ISWs bring nutrient-rich bottom water to the surface enriching marine life around the atoll. This is an important ecosystem for the ambient noise study to categorize the source of underwater sound and general soundscape. Four Passive Miniature Acoustic Recorders (PMARs) developed by the Applied Physics Laboratory, University of Washington were deployed in 2018 and 2019 within and near the outer bank of reef ring at the depth of ∼10 m. The PMARs collected the ambient noise from 100 to 50 kHz about 2–3 months each year. There are clear diurnal signals in pre-dawn and dusk periods with a peak frequency at 10 kHz. The noise level is about ∼5 dB higher than the background noise. The outer reef has a higher noise level (∼8 dB) than the inner reef due to stronger biological activities. In general, biological noise is the dominant source in this reef ecosystem, yet during the typhoon Mangkhut the wind noise is much higher at the lower frequency (below 3 kHz) and the near-surface bubbles layer generated during the typhoon inhibited the sound transmission which causes the lower noise level above 5 kHz.
Minimal COVID-19 quieting measured in the deep, offshore waters of the U.S. Outer Continental Shelf
Authors: Miksis-Olds Jennifer , Martin S. B. , Lowell Kim , Verlinden Christopher , Heaney Kevin D.
Published: November 2021

The Atlantic Deepwater Ecosystem Observatory Network (ADEON) provided an opportunistic dataset to examine potential COVID-19 effects in a deep, offshore region of the US southeastern Outer Continental Shelf (OCS) to determine if the quieting documented in coastal soundscapes extended to deep, offshore waters. A two-year time series of one-minute sound pressure level averages was calculated from 2019–2020 at the seven ADEON sites extending along the OCS from Virginia to Florida. Sites ranged in depth from approximately 200–900 m and in distance to the shelf break and shipping lanes. Sound pressure level metrics in decidecade, shipping-related bands were compared between years. Results indicate that the drastic drop in ocean sound levels experienced in coastal areas did not extend to all the ADEON sites. Sound level decreases were observed at sites closest to the shelf break and shipping lanes, while relatively no change was observed at other sites. These observations are consistent with AIS vessel tracks within 100 km of each ADEON bottom lander that showed increased numbers in 2020 compared to 2019 at majority of the offshore sites. [Study concept, oversight, and funding provided by BOEM, in partnership with ONR and NOAA. Funding for ship time was by ONR, Code 32.]
Modelling the global soundscape: Validating a study of the COVID-19 impact using in-shore and off-shore observatory data
Authors: Muzi Lanfranco , Verlinden Christopher , Heaney Kevin D.
Published: November 2021

This study presents a data-model comparison of the soundscape in the Northeast Pacific Ocean in 2019 and 2020. Focussing on frequencies below 400 Hz, where the soundscape is dominated by shipping, marine mammals (at selected frequencies) and large storms, a parabolic-equation model computes the propagation loss from a grid of points to a four-dimensional, high-resolution grid of receivers. The modelling data are extracted from a dynamic model of the global shipping and wind noise soundscape that utilizes AIS ship-tracking data. A comparison of the modelling results between 2019 and 2020 revealed a marked difference, reasonably due to the COVID-19 global shutdown. These results are compared to measurements from the long-term time series collected by Ocean Networks Canada’s in-shore and off-shore cabled observatories in the Salish Sea and Northeast Pacific Ocean.
Image-guided focused ultrasound-mediated drug delivery andcomparison between 2-D and 3-D therapeutic strategies
Authors: Margolis Ryan , Basavarajappa Lokesh , Li Junjie , Hoyt Kenneth
Published: November 2021

The objective of this research was to test a new US image-guided FUS (USgFUS) system for stimulating microvascular permeabilization and enhancing intratumoral drug delivery in volume space. 3-D USgFUS therapy functionality was implemented on a programmable US system with a dual transducer for interleaved imaging and 3-D therapy. 3-D therapy consisted of focal zones distributed over a user-defined volume whereas 2-D treatment had the same focal zones but about a single plane. Using breast cancer-bearing mice (N = 4), US therapy was conducted with a mechanical index of 0.5, pulse repetition frequency of 10 Hz, and duty cycle of 10%. Therapy was performed immediately after a 100 μl bolus injection of microbubbles and IR-780 dye. In-vivo optical imaging was performed at 0, 24, and 48 h. Tumors were then excised for ex-vivo analysis. 3-D USgFUS treatment increased dye extravasation within the tumor space at 24 (245.5%) and 48 h (297.5%) when compared to 2-D US therapy (p = 0.01). Ex vivo optical images revealed a similar trend with 3-D US treatment producing a higher fluorescent signal than the 2-D approach. Preliminary results suggest that 3-D USgFUS-mediated drug delivery is an exciting prospect for treatment of the entire cancer burden.
Reversible increase in the EKG of rats using transthoracic pulsed ultrasound
Authors: Coiado Olivia , Yerrabelli Rahul , Lucas Alex , Christensen Anton , Wozniak Marcin , O'Brien William D.
Published: November 2021

This study showed the ability to increase inotropy in a rat heart while maintaining hemodynamic stability. A total of fourteen rats were used in this experiment. They were divided into four group including a control group (no ultrasound exposure). 3-month-old female rats were transthoracically to 3.5 MHz ultrasonic pulses of 2.0-MPa peak rarefactional pressure amplitude, ∼0.5% duty cycle and an increase pulse repetition frequency (PRF) sequence (4–5–6, 5–6–7, and 6–7–8 Hz). All rats underwent the same anesthesia, preparation, measurement, and positioning with only experimental rats being exposed to the turned-on transthoracic ultrasound. Rats were positioned in dorsal recruitment position and cardiac parameters were monitored using EKG and echocardiography. An increase in the heart rate was observed followed by each PRF sequence with increased heart rates. A mean of 550 + -50, 563 ± 45, and 712 ± 61 bpm at the conclusion of ultrasound for 4–5–6 Hz, 5–6–7 Hz, and 6–7–8 Hz sequences versus the control baseline of 248 ± 19 bpm was achieved. Other cardiac parameters were normal or had a compensatory decrease by 3- and 15-min post-ultrasound compared to control. EKG data of the experimental group of rats showed areas of rapid peaks outside of sinus rhythm during ultrasound pulsing while the control group-maintained sinus rhythm throughout the experiment.
Validation of the spatial resolution of super-resolution ultrasound imaging using vessel mimicking microfluidic channels
Authors: Chen Qiyang , Kim Kang
Published: November 2021

Super-resolution ultrasound (SRU) imaging is an emerging technology that can identify microvessels with unprecedented spatial resolution beyond the acoustic diffraction limit. Our group introduced a deconvolution-based SRU imaging technology and successfully applied it on mouse and human kidneys for assessing the renal microvascular changes during the progress of kidney diseases. However, a thorough validation on the most achievable spatial resolution has not yet been systematically performed due to the limitation with in vivo imaging including imperfect co-registration between SRU image and ground truth such as histology. In this study, we evaluated the spatial resolution of our SRU imaging algorithm using a custom-designed PDMS microfluidic channels as the ground truth. In the reconstructed SRU image, the two microchannels separated by wall-to-wall distance of 30 μm were successfully identified, which assured the expected spatial resolution of SRU using 15 MHz transducer. The validation using custom-designed microfluidic channels as the ground truth in the scale of tens of microns was performed for the first time to the best of our knowledge for SRU imaging. Such channels of various diameters and separation distances can be an effective tool for the systematic evaluation of the imaging capabilities of different SRU algorithms.
Evaluation of biological proxies for surgical instruments and their accuracy for acoustic decontamination techniques
Authors: Dolder Craig N. , Malakoutikhah Maryam , Secker Thomas J. , Leighton Timothy G.
Published: November 2021

Surgical instruments go through rigorous protocols involving decontamination and sterilization. Of particular concern is Variant Creutzfeldt-Jakob Disease, because (unlike viruses and bacteria) the prions responsible for this are not destroyed by the high temperatures, cleaning chemistries, and radiation used. This paper is part of a study on the effectiveness of ultrasonically-activated streams to remove dangerous prions from surgical instruments to prevent infections from spreading between patients. Cleaning techniques are often evaluated against standard surgical instrument substitutes in a test such as animal bioassays and amplification assays. These test uses thin wires (0.016 mm diameter), which are pre-contaminated, put through the cleaning process, and then sent for analysis to determine how much contamination remains. Despite being an industry standard with proven effectiveness as a proxy for cleaning surgical instruments using heat/chemicals/radiation, thin wires are shown to be a poor proxy when ultrasonically cleaned. The acoustics of thin wires and surgical instruments differ significantly and therefore the performance of acoustic cleaning methods can fail this test while being ultimately effective on surgical instruments. We present measurements on and in the vicinity of thin wires and steel plates to illustrate the differences between these two targets and discuss the reasons for this disparity.
Holographic lenses for the spatial patterning of particles toward tissue engineering in vivo
Authors: Ghanem Mohamed A. , Maxwell Adam D. , Dalecki Diane , Bailey Michael R.
Published: November 2021

For tissue engineering, cells are aligned along defined structures that allow for cellular agglomeration and regeneration. Acoustic radiation force has been used for the contactless generation of patterns. Particles that are much smaller than the wavelength are agglomerated along high pressure regions and the forces are predicted using Gor’kov potential. Ultrasound standing waves have been used in vitro to create parallel planes where the cells agglomerate allowing for vascular tissue growth between planes. Here, we design and build a single-sided source with a holographic lens made using Fourier spectrum approach to generate parallel lines of high pressure amplitude over a limited range, few wavelengths, for cellular patterning. A few sources were fabricated at 1.5 and 2 MHz using geometrical and holographic lenses. The phase generation from holographic lenses was improved using global phase unwrapping scheme. Acoustic holography measurement was performed for all sources to verify the pressure output. The cellular patterning was tested on polyethylene microspheres (75-90 μm in diameter) that were placed in a cuvette with water and exposed to ultrasound. The microspheres were aligned along the high pressure region as predicted. This work has the potential to use single-sided transducers for cellular patterning toward tissue engineering in vivo.
Cultural policy infrastructure and the representation of Nigeria’s music in education
Authors: Calilhanna Andrea , Adeogun Adebowale , Onwubiko Stephen G.
Published: November 2021

Serious systemic and unethical consequences of notation-based music theory, which focuses on tonality, include its contribution to excluding the discourse of most of the world’s music traditions because most of them are not notated. New projects seeking inclusion require the analysis of the meter for accurately documenting and discoursing music. The implications of the results of this study will likely involve significant music education policy and cultural infrastructure policy adjustments and change (Calilhanna, 2017, 2018, 2019, 2020, 2021; Calilhanna et al., 2019). Some of these changes will involve key competencies; other policies will require cultural heritage acknowledgement, further consideration to research-based evidence for transferable skills, and literacy and numeracy. A scientific approach to analysing similarities and differences of music traditions delves into finer details with suitable analytical instruments and processes. Yet most of the cultural contributions, the musical heritage of people worldwide, for example, the traditional music of post-colonial countries such as the Igbo in Nigeria, has been silenced, is at risk of extinction, remains unaccounted for or is inaccurately explained. Cohn’s (2020) psychoacoustic approach to the meter is discussed through visualising the beat-class in a three-step approach with the ski-hill, circle, and linear, cyclic graphs.
Better than concrete. Light-weight fitness floating floor solutions for reducing impacts
Authors: Wells Adam P.
Published: November 2021

Structure-borne noise and vibration from weight drops and fitness activities are an ever-increasing source of disturbance within multi-residential, hospitality, and multi-tenant commercial buildings. High-mass floating floors supported on low-resonant frequency isolators have been used with good effect to reduce impact noise and vibration, but commonly require expensive supplemental supports or structural stiffening to be implemented properly. Common light-touch fitness solutions feature continuous or interlocking resilient surface treatment. This approach is often ineffectual at high-energy impact fitness areas and the pursuit of soft surface solutions to achieve greater dissipation of impact energy can create an unstable surface for weightlifting. An alternate approach to reducing structure-borne noise exists which focuses on dissipating the impact energy through constrained layer damping in conjunction with low-resonant frequency isolators. Research and development testing shows that an engineered all-dry lightweight fitness floating floor is capable of achieving equal or greater impact insulation performance than a high-mass concrete floating floor and significantly better performance than light-touch resilient surface treatment. A review of the testing and development process and underlying principles will be reviewed to illuminate the mechanisms at work in the next generation of fitness floating floors.
Physical and acoustic response of Pinus palustris to fire
Authors: Yedinak Kara M. , Hiers J. K. , Grob Ian , Riser James P. , Pokswinski Scott
Published: November 2021

Crackling sounds from burning vegetation provide information to fire-experienced land managers regarding the combustion process. These acoustic impulse events can inform practitioners of a variety of situations, from the type of vegetation involved and relative “dryness,” to alerting wildland fire fighters to increased burning along tree boles and in canopies. More recently, acoustic sampling has supported these observations by quantifying species and drought-stress specific differences in the acoustics impulse events in both the laboratory and field. Our team builds on this work by quantifying the response of long leaf pine (Pinus palustris) in grass-stage to low-intensity fire. We planted live fuel beds in Northern Florida with long leaf pine seedlings. We then used prepared dead long leaf pine needles to carry low-intensity fire past the live plants. Crackling sounds from both the live and dead needles were recorded. These acoustic impulse events were then analyzed to identify any unique characters associated with the live and dead needles. We pair these results with single leaf-cluster scale laboratory experiments in which we documented the mechanical and acoustic response along the axial extent of the leaves. We present the results of long leaf pine’s acoustic and mechanical response to low-intensity fire.
Using bulk acoustic waves for filtering microplastic on polluted water
Authors: Arifianto Dhany , Sari Berliana N. , Urrohma Laila S. , Permana Dian , Felle Arkilaus B.
Published: November 2021

Microplastic is known as one of the polluted objects on seawater which can contaminate marine biota. In this report, we designed microplastic filters using Bulk acoustic waves. Two speakers were added to the design to create acoustic waves, and three channels were created on the tube where the polluted water flows. The force produced by the wave can separate the microplastic from the polluted water by creating node pressure on the tube, so it presses microplastic particles towards the center of the channel, whereas the clean water on the other two channels. Using this method, the filter can filter all microplastics and have an efficiency of up to 99% for nylon and 95% microplastics.
Passive structural health monitoring using an acoustic digital twin
Authors: Sternini Simone , Bottero Alexis , Sarkar Jit , Kuperman William
Published: November 2021

This work presents simulation results on passive structural health monitoring of a vibrating elastic structure for defect localization. We consider an object that consists of a shell with vibration sensors surrounding a complex, vibrating structure such that they are coupled at a finite number of points. The non-defective model of the external shell is called an acoustic digital twin (ADT). We use a combination of the concept of an acoustic digital twin (ADT) together with an adjoint-based high resolution array processing approach to detect a defect. The “dataset” in the presence of a defect was obtained from simulations and was “measured” on a linear array placed on the surface of a candidate ADT. A set of sensors placed at the connecting points provides the time histories of the excitation forces, which are used as inputs to the ADT in order to obtain the fields at the surface in the unperturbed case (no defect). The residual field (difference between defect and non-defect case) was used in the Matched Field Processing (MFP) algorithm in order to successfully locate the defect on the surface of the object.
Nonlinear ultrasonic testing for evaluation of fracture toughness in 4130 steel
Authors: Williams Colin , Borigo Cody , Riviere Jacques , Lissenden Cliff , Shokouhi Parisa
Published: November 2021

An estimation of plane strain fracture toughness [endif]--> is essential to assess the operational safety of fracture-critical systems; loss of [endif]-->can lead to catastrophic failure. However, it is not possible to quantify [endif]-->in situ; the laboratory testing to determine [endif]-->is destructive. Here, we investigate nonlinear ultrasonic testing as a nondestructive method to evaluate [endif]-->. This is based on a hypothesized correlation between the nonlinear ultrasonic parameters and [endif]-->characteristics of a material given their mutual dependence on microstructure. Using Second Harmonic Generation (SHG), surface and bulk waves are used to measure the (relative) nonlinearity parameter for tempered 4130 steel samples. Coupons made of the same materials are also tested for their [endif]-->characteristics using Charpy V-Notch testing, providing a direct comparison between destructive and nondestructive measures. Our results show correlations between ultrasonic parameters and [endif]-->characteristics of 4130 steel samples, but different relations are observed for bulk and surface waves. The observed differences are possibly due to sample heterogeneity and different wave structures of the two wave modes and should be further investigated. We demonstrate the potential of nonlinear ultrasonic testing for [endif]-->estimation. The ultimate goal is developing a nondestructive method to assess [endif]--> in situ.
High frequency ultrasonic scattering from cracks in orthotropic silicon wafers
Authors: Katch Lauren , Arguelles Andrea
Published: November 2021

Silicon wafers, commonly used in the photovoltaic industry, are susceptible to cracking during manufacturing and processing that may impact their performance. These microscale cracks are difficult to detect ultrasonically due to the anisotropic nature of silicon and the high frequencies necessary for inspection. For instance, phased array (PA) approaches commonly used to detect and size cracks are unsuitable for this application due to the frequency constraints of commercial PA systems. Therefore, crack scattering in anisotropic media has mostly been studied from a theoretical perspective and little work has been done from an experimental lens. In this presentation, we experimentally evaluate ultrasonic scattering from cracks in submillimeter silicon wafers using single-element 100 MHz probes. We use an oblique-incidence, pulse-echo configuration to spatially map shear scattering from cracks at different orientations in orthotropic silicon samples. Our results illustrate the strong scattering dependence on crystal orientation and elucidate the complexities in the response as a function of the planes of symmetry. These results will enable more in-depth sensitivity analysis for crack detection and characterization in anisotropic samples.
Effects of uvular consonants on vowel quality in Lushootseed
Authors: Kye Ted K.
Published: November 2021

Although the influence of uvular consonants on vowel quality has been studied in Interior Salish languages (Bessell, 1992; 1998; Flemming et al., 2008), it has not been studied in Coast Salish languages. This study investigates the effect of uvular consonants on vowel quality in Lushootseed, a Coast Salish language spoken in the Puget Sound region of the Pacific Northwest, which has uvular stops and fricatives. Archival recordings (Burke Museum, 2015) of a native speaker were examined. A study was performed to analyze the effects of uvular consonants on formants of adjacent vowels. F1 and F2 were measured for vowels adjacent to uvular consonants that were positioned pre- and post-vocalically. These measures were compared with vowels adjacent to non-uvular consonants. The results reveal that there was an increase in F1 and a decrease in F2 for all vowels. The effects were greater for F1 than F2. These results are in contrast with those of Bessell (1992; 1998), who observed two effects: (i) only non-low vowels were affected, and (ii) F2 showed a greater effect than F1. These findings provide further implications on acoustic phonetic research for Coast Salish languages.
Speaking rate and language-specific voice onset time effects on burst amplitude: Cross-linguistic observations and implications for sound change
Authors: Narayan Chandan
Published: November 2021

The relationship between speaking rate and burst amplitude in voiceless plosives was investigated in two languages with differing oro-laryngeal timing implementations of phonological voicing, North American English and Indian Tamil. Burst amplitude (reflecting both intraoral pressure and flow geometry of the oral channel) was hypothesized to decrease in CV syllables with increasing speaking rate, which imposes temporal constraints on both intraoral pressure buildup behind the oral occlusion as well as respiratory air flow. Increased speaking rate led to decreased burst amplitude (relative to vowel amplitude) in both languages, with the magnitude of the effect being considerably weaker in Tamil, which has short-lag implementation of voice onset time. Bilabials in both languages were affected disproportionately relative to other places of articulation. Additionally, burst amplitudes were lower overall in Tamil, reflecting lower intraoral pressure which promotes faster vocalic onset. Results are discussed in terms of language-internaland extra-linguistic phonetic phenomena potentially serving as perceptual triggers for historical sound change.
Beyond midpoints: Vowel dynamics of the low-back-merger shift
Authors: Stanley Joey
Published: November 2021

The Low-Back-Merger Shift—the lowering/retraction of /æ/, /ɛ/, and /ɪ/—is a now-well-studied phenomenon of American English. However, it is primarily described by the relative position of the vowels using single-point acoustic measurements. This study seeks to fill an apparent gap in the literature by describing change in these vowels’ formant trajectories. Data come from 45 h of sociolinguistic interviews conducted in southwest Washington (ages 18–86). A generalized additive mixed-effect model (Wood, 2007) fit to pairs of formant measurements extracted at 11 timepoints per vowel token confirms that the lax vowels are shifting and uncovers changes in their formant dynamics in apparent time. For instance, the bulk of /æ/ lowering and retraction is a result of its onset shifting rather than the offset. For all three vowels, the amount of change in F2 over the vowel’s duration decreased over time, resulting in qualitative changes in the shape of the vowel trajectory (when visualized in the F1-F2 space). Furthermore, though the men lagged behind the women in relative position in the vowel space, both genders changed the shape of their trajectories at the same time. This study shows that there is more to vowel shifts than changes in their midpoints.
Sample size matters when calculating Pillai scores
Authors: Stanley Joey , Sneller Betsy
Published: November 2021

Pillai scores, an output statistic from a MANOVA model, are used to measure acoustic overlap between two merging, splitting, or shifting vowels (Hay et al., 2006; Nycz & Hall-Lew, 2013, inter alia). They range from 0 (complete overlap) to 1 (complete separation). In this paper, we demonstrate that sample size matters in two important ways when calculating Pillai. First, relatively small datasets (<60 per sample) tend to underreport mergers. In simulated data, we draw two samples (5–100 tokens in each) from the same normal distribution to represent two vowels known to be merged. We find that a sample size of at least 60 tokens is required for at least 95% of the iterations to return a Pillai score less than the commonly used threshold of 0.1. s, Pillai scores are sensitive to the difference in sample sizes across two samples, with large differences resulting in Pillai scores that overreport mergers for samples drawn from two distinct distributions. If Pillai scores are used to measure vowel overlap, we recommend (1) using the same number of tokens across both samples and (2) using p-values from the MANOVA model to accompany them to assess whether the difference between two distributions is significant.
Effects of vowel devoicing on the closure duration of japanese singleton and geminate stops
Authors: Yamakawa Kimiko , Amano Shigeaki
Published: November 2021

Closure duration is an acoustic variable known to distinguish Japanese singleton and geminate stops. It has been established that the closure duration varies with speaking rate. However, it has not been determined whether the closure duration is affected by devoicing of vowels preceding or following the stops. To determine the effects of such vowel devoicing, a production experiment was conducted with 20 Japanese native speakers. They pronounced four minimal pairs of onomatopoeic words contrasting singleton and geminate stops at various speaking rates. Devoiced vowels were found to affect closure duration preceding the stops, such that the closure with a devoiced preceding vowel is longer than that with a voiced preceding vowel, although the effect is weak for singleton stops. However, devoiced vowels do not affect the duration when they follow stops. These results suggest that vowel devoicing interacts with an acoustic variable of stop consonants, especially in the case of geminate stop.
Coarticulation across communicative contexts: An acoustic analysis of the LUCID corpus using spectral and temporal measures
Authors: Guo Zhe-chen , Smiljanic Rajka
Published: November 2021

Coarticulation reflects a balance between talker efficiency and speech comprehension. This study examines coarticulation across different communicative contexts in the LUCID corpus. The talkers completed an interactive spot-the-difference task with a listener when there were no communication barriers (NB), when their speech was vocoded (VOC), when it was masked by multi-talker babble (BABBLE), and when the listener was an English language learner (L2). They also read sentences without an interlocutor conversationally (READ-CO) and clearly as if talking to someone with hearing loss (READ-CL). The spectral distance and the relative duration of coarticulatory transition between the adjacent segments were computed. Both measures showed that speech produced in the presence of a communication barrier (BABBLE, VOC, L2, and READ-CL), be it real or imagined, is more resistant to coarticulation than speech produced in the barrier-free conditions (NB and READ-CO). Spectral distance was more sensitive to differences among all conditions involving a real listener (BABBLE, VOC, L2, and NB) while relative transition duration measure better captured differences between read and spontaneous speech for the barrier-present conditions (BABBLE, VOC, L2, and READ-CL). The results suggest that talkers reduce coarticulation in response to the particular communication challenges which may aid speech perception.
Dissimilatory interactions among lexical tones are mediated by speech rate: Evidence from Thai
Authors: Burroni Francesco , Tilsen Sam
Published: November 2021

The pitch targets of lexical tones in adjacent syllables exhibit interactions that are reminiscent of the coarticulatory effects typical of segments (Gandour, 1994; Xu, 1994). However, unlike segmental coarticulation, which is primarily assimilatory, lexical tones also exhibit dissimilatory interactions. For instance, tones with a high pitch target have been reported to reach even higher targets before a dissimilar low tone than before a similar high tone; a phenomenon known as pre-low raising (Lee et al., 2021). Our contribution focuses on two aspects of tonal coarticulation: the existence of dissimilatory pre-high lowering effects, and the role of speech ratein coarticulatory effects. A production experiment was conducted with 20 speakers of Bangkok Thai, who produced disyllabic combinations of Falling/Rising tones before all the five tones of the language (Mid/Low/Falling/High/Rising) in carrier sentences at a variety of speech rates. Results show the existence of both pre-low raising and pre-high lowering dissimilatory effects in Bangkok Thai. Further, the dissimilatory effects are weaker at higher speech rates. The interaction between speech rate and the strength of dissimilatory effects suggests that tonal dissimilation may be primarily driven by articulatory target planning mechanisms rather than perceptual enhancement (Lee et al., 2021).
An unexpected journey through sound
Authors: Porter Tyrone M.
Published: November 2021

Growing up in Detroit in the 1980s, I never envisioned a career in acoustics…not because I was told I could not but because I wasn’t told I could. I did not learn about the academic and professional opportunities in biomedical ultrasound until halfway through my undergraduate program. But as a doctoral student, the lack of Black representation in acoustics raised many doubts and fears…doubts in my own abilities and fears that the acoustic community would not accept me. I was embraced by members of the ASA, which empowered me to take the road less traveled. I am here today to share how this unexpected journey through sound has shaped me personally and professionally and thoughts on how I and the ASA can continue to broaden participation in acoustics.
Hierarchical classification of multi-corpus acoustic field recordings
Authors: Morgan Mallory , Braasch Jonas
Published: November 2021

Passive acoustic monitoring is one important technique for detecting long-term ecological change. Since audio data contains complex temporal and frequency information, deep learning is an ideal computational framework for automatic processing. In this work, the dataset consists of 64k annotated clips distributed across 23 classes that are derived from 17 000 h of acoustic data consisting of bio-, geo- and anthropophonies recorded at two different sites in the Capital Region of New York State. A hierarchical deep convolutional neural network with one local classifier per parent node provides fine, medium, and coarse-grained label predictions. If a fine-grained label is predicted incorrectly, a correct medium or coarse label still provides valuable taxonomic information. While the flat classifier performs similarly to the hierarchical for single-corpus training scenarios, it achieves higher medium-grained predictions for categories such as avian vocalization. For cross-corpus scenarios, the hierarchical classifier achieves a superior performance overall. These results highlight the importance of neural network architecture customization to suit a particular task and domain; hierarchical structures show potential in open set recognition tasks, where the entire set of possible classes is unknown. [Work supported by NSF Grant No. 1631674 and an RPI HASS Fellowship.]
The next wave of passive acoustic data management: How centralized access can enhance science
Authors: Wall Carrie , Haver Samara , Hatch Leila , Miksis-Olds Jennifer , Bochenek Rob , Dziak Robert P. , Gedamke Jason
Published: November 2021

Passive acoustic data collection has grown exponentially over the past decade resulting in petabytes of data that document our ocean soundscapes. This effort has resulted in two big data challenges: the curation, management, and global dissemination of passive acoustic datasets and efficiently extracting critical information and comparing it to other datasets in the context of ecosystem-based research and management. To address the former, the NOAA National Centers for Environmental Information established a passive acoustic data archive, which contains over 100 TB of audio files mainly collected from stationary recorders throughout waters in the U.S. These datasets are documented with standards-based metadata and are freely available to the public. To begin to address the latter, through standardized processing and centralized stewardship and access, we will present a previously unattainable comparison of first order sound level-patterns from archived data collected across three distinctly separate long-term passive acoustic monitoring efforts conducted at regional and national scales: NOAA/National Park Service Ocean Noise Reference Station Network, the NOPP-funded Atlantic Deepwater Ecosystem Observatory Network, and the NOAA-Navy Sanctuary Soundscape Monitoring Project. Further, we will propose the next frontier for scalable data stewardship, access, and processing flow to help the community collaboratively move forward.
Rapid estimation of empirical Green’s functions for passive acoustic characterization of dynamic shallow-water environments
Authors: Tan Tsu Wei , Godin Oleg A. , Shen Yi-fan
Published: November 2021

Applications of acoustic noise interferometry to passive remote sensing of the ocean and improvement of sonar performance predictions rely on retrieval of empirical Green’s functions (EGFs) from synchronized measurements of ambient sound at spatially separated points. Usually, long noise averaging times of many hours and even days are employed to achieve precise passive measurements of the ray or normal mode travel times that are necessary for evaluation of the environmental parameters with oceanographically relevant accuracy. However, long averaging times have limited utility when nonlinear internal waves or other oceanographic processes cause significant, time-dependent variations in sound propagation conditions. Analysis of the noise records acquired during the Shallow Water 2006 experiment reveals that EGFs can be reliably retrieved from cross-correlations of noise recorded over periods as short as 10 minutes by moored receivers horizontally separated by 40–50 ocean depths. The measured EGFs evolve as the sound speed field changes. Suitability of the EGFs for acoustic remote sensing is demonstrated by geoacoustic inversion of the passively measured normal mode dispersion curves and comparison to previously reported inversion results. Rapid EGF retrieval has far-reaching implications for operational use of the underwater acoustic noise interferometry. [Work supported by NSF.]
Quantifying the influence of the range and motion of shipping sources on the ray-based blind deconvolution (RBD) algorithm
Authors: Touret Richard X. , Durofchalk Nicholas C. , Sabra Karim G.
Published: November 2021

The ray-based Blind Deconvolution (RBD) can estimate the relative arrival-times of the channel impulse responses (CIRs) between a shipping source (acting as a shallow source of opportunity) and a remote receiver array (e.g., a short bottom-mounted vertical line array (VLA)) [Durofchalk & Sabra, JASA Vol. 147(3), p. 1927–1938, 2020]. Previous RBD studies primarily estimate the phase of the unknown source by using beamforming on the (most energetic) direct path, which is only observable at short ranges for a shipping source in typical downward refracting environments. Alternatively, when dealing with long range sources of opportunity and only bottom-interacting multipath arrivals can reach the VLA (i.e., exceeding the range when the direct path is observable), the general performance of the RBD algorithm remains to be evaluated. In this study, numerical simulations and experimental validation (using short bottom mounted VLAs) are used in conjunction to investigate the maximal detection range of shipping sources of opportunity per multipath arrivals as a function of frequency, Doppler effect and anisotropy of the shipping source, and the implications for the accuracy of the relative arrival time of the CIR estimated with RBD.
Modeling and observation of low-frequency propagation into warm core ring on the New England shelf slope
Authors: Reeves Ozanich Emma , DeCourcy Brendan J. , Lin Ying-Tsong
Published: November 2021

Analytical and computational modeling is used to examine propagation of low-frequency sound into a warm core ring oceanic front. When the source is placed outside the front and the receiver is placed inside it, the sound field consists of the refracted path and the horizontal lateral wave, which decays exponentially into the front. The analytical solution is presented in 2D (x, y) assuming an adiabatic vertical mode solution in z, wherein the vertical mode-dependence of the propagation paths into the front are considered. A 3D computational acoustic model examines the additional effects of sloping bathymetry and frontal geometry. The modeled results are compared to experimental measurements of into-front propagation during the March 2021 New England Shelf Break Acoustics Experiment using a low-frequency (fc = 115 Hz), shallow towed chirp signal received on an L-shape vertical and horizontal hydrophone array. [Work supported by the Office of Naval Research.]
Real-time acoustic modeling in the New England Shelf Break Experiment
Authors: DeCourcy Brendan J. , Lin Ying-Tsong , Zhang Weifeng G.
Published: November 2021

During the New England Shelf Break Acoustics Experiment (NESBA) in May of 2021, signals emitted and received by instruments on deployed moorings were successfully modeled while at sea. Using a combination of physical oceanography models and data collected from CTD measurements to determine the sound speed, both parabolic equation (PE) and ray tracing methods were used to model signals received by hydrophones as part of the experiment. Qualitative comparison between model output and hydrophone data was used to inform model adjustments to better represent the acoustic data, ultimately producing a promising data/model agreement during the cruise. Post-cruise research involved incorporation of additional data from the NESBA cruises and model adjustments to more adequately reflect the environmental properties of the experiment site. The success of the initial real-time modeling tests and subsequent improvements to the techniques support their use in future field experiments. [Work supported by the Office of Naval Research.]
Elastic properties of human hematoma model and its sensitivity to histotripsy liquefaction
Authors: Ponomarchuk Ekaterina M. , Rosnitskiy Pavel , Tsysar Sergey A. , Khokhlova Tatiana D. , Karzova Maria M. , Tyurina Anastasia V. , Tumanova Kseniya D. , Kadrev Alexey V. , Buravkov Sergey V. , Trakhtman Pavel E. , Starostin Nicolay N. , Sapozhnikov Oleg A. , Khokhlova Vera A.
Published: November 2021

The efficiency of various histotripsy approaches for mechanical tissue ablation has been reported to depend on tissue elastic properties. Here the efficiency of histotripsy liquefaction of human hematomas is investigated in dependence on their shear modulus value and retraction degree. Recalcified anticoagulated blood samples (200 ml) served as an in vitro hematoma model. Shear wave elastography was used to measure changes of the samples shear modulus during clotting at different temperatures and during 10-day retraction. Boiling (2.5 ms-pulses) and hybrid (200 μs-pulses) histotripsy lesions (2 MHz operational frequency) were produced and sized in samples of varying retraction degrees. The clotting time decreased from 113min to 25 min with the increase in blood temperature from 10 to 37°C. The shear modulus increased to 0.53 ± 0.17 kPa during clotting and remained constant within 10-day storage at 2°C, whereas the volume of clotted samples decreased by 57% due to retraction. The lesions produced with the same histotripsy protocols in retracted samples were smaller in size versus freshly clotted ones correlating with the increase in retraction degree. The results demonstrate that the hematoma sensitivity to histotripsy liquefaction is not fully defined by its shear modulus. [Work supported by NIH R01GM122859, RFBR 20-02-00210, FUSF, and “BASIS” Foundation 20-2-10-10-1, 20-2-1-83-1.]
Boiling histotripsy dose for mechanical ablation of human prostate tissues with different elastic properties
Authors: Rosnitskiy Pavel , Tsysar Sergey A. , Karzova Maria M. , Ponomarchuk Ekaterina M. , Tyurina Anastasia V. , Tumanova Kseniya D. , Buravkov Sergey V. , Kadrev Alexey V. , Khokhlova Tatiana D. , Schade George R. , Sapozhnikov Oleg A. , Maxwell Adam , Chernyaev Andrey , Khokhlova Vera
Published: November 2021

Boiling histotripsy (BH) is a promising technology for transrectal mechanical ablation of localized prostate cancer. BH uses sequences of milliseconds-long pulses to generate high-amplitude shocks in acoustic pressure waveforms at the focus, resulting in non-thermal liquefaction of pathological tissue. Despite successful pilot experiments on BH ablation of fresh human prostate, a critical problem remains on determining the threshold values of the BH-dose (the number of pulses per focus for specific exposure protocols) sufficient for tissue ablation. This threshold depends on the stiffness of tissue, which varies in different patients and different prostate tissue types. Here, BH lesions were induced in ex vivo prostate tissue samples (n = 14) with different values of shear modulus and using different BH doses. The 2-MHz transducer operated with exposure parameters: 10-ms pulses, 1% duty cycle, and 10–40 pulses/point. After sonication, the samples were analyzed histologically to assess cell destruction. The experiment demonstrated varying completeness of tissue liquefaction for various BH-dose depending on the tissue stiffness. [Work supported by RSF 21-72-00067.]