bluuebunny/crossref_metadata_2025 huggingface dataset:
Determining the speed dependent source level of a snowmobile traveling on sea-ice
Authors: Cook Emmanuelle , Winters John , Anthony Katrina , Barclay David R. , Oliver Eric
Published: November 2022

As part of the Sustainable Nunatsiavut Futures project, a field experiment to determine the acoustic properties and underwater radiated sound level of a snowmobile was designed and executed. The fieldwork consists of lowering acoustic recorders under the sea ice and driving a snowmobile with a known position and velocity to evaluate its speed-dependent source level. This experiment is the first step toward collaborative Dalhousie and community research on underwater sound as it relates to the marine habitat, human use of the ocean, and sea-ice in Nunatsiavut. Due to COVID-19, the planning stages were coordinated virtually, and the fieldwork in Nunatsiavut was conducted by local Inuit Research Coordinators (IRCs), while a twin Dalhousie-led experiment was conducted in Caraquet, New Brunswick. A single hydrophone sensor was used in Nunatsiavut, and a vertical array of hydrophones was used in Caraquet to obtain underwater sound data from a moving snowmobile. Skidoo specifications for each site were recorded as well as sea-ice thickness, temperature, salinity, and sound-speed data were collected. Spectrograms of skidoos traveling at different speeds were computed. Comparisons between received levels at different velocities, sites, and ranges are shown, and the impact of sea ice and snowmobile specifications on received levels are discussed.
Simulation of acoustic reflection from Arctic ice
Authors: Chotiros Nicholas P.
Published: November 2022

The acoustic reflection from an ice sheet in the arctic, as observed by an upward looking sonar, is simulated. The reflection from a smooth ice sheet is modeled using OASES, using material properties that may be found in the published literature. Depending on the bandwidth of the signal, specular reflections from the top and bottom of the ice, as well as one or more resonances that are identified as leaky Lamb waves should be detectable. If the speed of the Lamb wave is faster than the speed of sound in water, it will leak energy back into the water. The leaky Lamb wave has a characteristic resonant frequency that is a function of the ice thickness and shear speed. The reflection and backscatter from a rough ice sheet is modeled using SPECFEM2D. Scattering from a rough interface may obscure the expected signals, depending on the severity of the roughness. [Work supported by ONR, Ocean Acoustics Program.]
Ultrasound elastography evaluation of age-related eye lens nucleus stiffness: A porcine eye study
Authors: Abdus-Shakur Tasneem , An Justin , Denis Max
Published: November 2022

In this work, ultrasound elastography is employed to evaluate age-related changes of eye tissues. Of particular interest is the eye lens nucleus stiffness. Age-related changes in the eye lens nucleus stiffness are one of the most important causes of cataract. Ultrasound elastogram studies are performed by mechanical scanning porcine eyes using a handheld ultrasound system. Employing deep learning techniques, tissue stiffness assessments are made to differentiate porcine eyes with and without cataracts. Results and limitations of the elastogram assessment will be presented and discussed.
Assessing the effect of poly (ethylene oxide-b-lactide) block copolymer on the characteristics of perfluoropentane phase-shift nanoemulsions
Authors: Al Rifai Nour , Haworth Kevin J. , Abid Shameel
Published: November 2022

Acoustic droplet vaporization is the ultrasound-mediated phase shift of liquid perfluorocarbon emulsions into echogenic microbubbles. To reduce the emulsion's interfacial surface tension and minimize coalescence, the perfluorocarbon is coated with a surfactant. Copolymer shelled phase-shift nanoemulsions have emerged as potential diagnostic and therapeutic agents. The goal of this study is to understand how adding Poly (ethylene oxide-b-lactide) (PEO-PLLA) to a Pluronic F-68 shell formulation impacts the perfluoropentane (PFP) nanoemulsion size and polydispersity index (PDI). PFP nanoemulsions coated with Pluronic F-68 or a Pluronic F-68: PEO-PLLA (1:0.05 (v/v)) blend was prepared using high shear pressure homogenization (LV1, Microfluidics International, Corp.). Nanoemulsion size distributions and concentrations were measured (n=5) using a Beckman Coulter Multisizer 4. At 10,000 psi pressure and 1 passage through the homogenizer, the copolymer blend and Pluronic F-68 nanoemulsions had modal diameters of 0.73 ± 0.09 μm and 1.25 ± 0.09 μm, respectively. Additionally, the concentration was larger (6.6 ± 0.1×10−2 vs 5.56 ± 0.2×10−2 ml/ml) and the PDI smaller (0.070 ± 0.004 vs 0.129 ± 0.004) for the copolymer blend. All differences were statistically significantly different (p < .05). The inclusion of PEO-PLLA with Pluronic F-68 reduced the PFP nanoemulsion size and polydispersity, which may reduce experimental variability in acoustic droplet vaporization experiments.
Towards a phase diagram for the process of acoustic droplet vaporization
Authors: Coulouvrat Francois , Lacour Thomas , Valier-Brasier Tony
Published: November 2022

The phase-change of a liquid droplet exposed to an oscillating acoustic field is known as “acoustic droplet vaporization.” It potentially represents a versatile tool for medical applications. In an attempt to understand the complex mechanisms that drive the vaporization process, a theoretical and numerical model is developed to describe the time evolution of a three-phase phase model, made of an initial (nucleus) bubble of vapor perfluorocarbon, at the center of a liquid droplet of the same perfluorocarbon immersed in water. The effect of an encapsulating layer can also be taken into account. The model is solved numerically to compute the vapor bubble and liqud droplet evolution with time. The dynamics are sorted into six different regimes depending on their characteristics and on the system ultimate fate. Those regimes can be organized within a phase diagram that synthesizes all the possible dynamics, predicting whether the complete vaporization occurs or not depending on the two control parameters, the amplitude and the frequency of the driving acoustical field. In particular, the dependance of the vaporization threshold with frequency is discussed with two different behaviors at low or high frequency.
Acoustic cluster therapy (ACT®) for improved treatment of cancer and brain diseases
Authors: Mühlenpfordt Melina , Healey Andrew , Kvåle Svein , Olsman Marieke , van Wamel Annemieke , Snipstad Sofie , de Lange Davies Catharina
Published: November 2022

Systemic injections of chemotherapeutics often deliver only minor fractions of the administered dose to the targeted pathology, resulting in unwanted toxicity towards healthy tissue. In brain tissue, drug delivery is impaired by the highly selective nature of the blood brain barrier impeding the influx of most substances. Acoustic Cluster Therapy (ACT®) is a platform for targeted therapeutic enhancement, facilitating increased local drug transfer. The platform is comprised of ACT® clusters, a mix of microbubbles and microdroplets and low intensity (diagnostic) ultrasound insonation. Intravenously injected ACT® clusters circulate freely through the body before activation by localised insonation at the targeted pathology. In the ultrasound field, microbubbles transfer energy to microdroplets, which undergo a liquid-to-gas phase transition, forming larger ACT® bubbles that transiently deposit in the targeted microvasculature. Further exposure to ultrasound results in controlled volume oscillation of the ACT® bubbles, inducing a range of biomechanical effects. The effects lead to enhanced extravasation across the endothelial barrier, facilitating the transport of co-administered chemotherapeutics to the targeted tissue. Proof of concept studies showed an increased therapeutic efficacy of standard of care drugs, when combined with ACT® treatment. Furthermore, ACT® treatment induced a controlled and temporal opening of the blood brain barrier observed by the extravasation of fluorescent macromolecules into brain tissue.
A numerical and experimental study of micrometeorological effects on urban sound propagation
Authors: Gaye Samba , Mandjoupa Lirane , Davis Dorian , An Justin , Mahmoud Wagdy , wang lei , Denis Max
Published: November 2022

In this work, the influence of micrometeorological effects on sound propagation in an urban street canyon is investigated numerically and experimentally. Numerical simulations of acoustic propagation are based on sound particle propagation simulation method. Numerical data are generated for urban street canyons of various widths and height ratios. Experimental data are obtained from longitudinal measurements of urban street canyons in the United States. Temperature and wind profiles are obtained from ultrasonic anemometers and thermocouples. Measurements within and outside the street canyon are of particular interest. The experimental data are useful in integrating micrometeorological effects into the acoustic propagation model. Preliminary numerical results and measurements are presented and discussed.
Parabolic equation with arbitrary variations in the sound speed and Mach numbers of the medium velocity
Authors: Ostashev Vladimir E. , Wilson D. Keith , Dragna Didier , Colas Jules
Published: November 2022

Among computational techniques in atmospheric and ocean acoustics and other fields such as seismic wave propagation, the parabolic equation (PE) approach is one of most popular now. The PE is well suited to small computers, large domains, and high frequencies. It can handle many complicated phenomena such as atmospheric and ocean stratification and refraction, scattering by turbulence, internal waves, and other inhomogeneities, ground impedance and ocean bottom interactions, and propagation over slowly varying terrain and ocean bathymetry. PEs are usually formulated for small variations in the sound speed and small Mach numbers of the medium velocity. However, these assumptions might result in significant phase errors of propagating sound waves. In this presentation, a PE is formulated for arbitrary variations in the sound speed and arbitrary Mach numbers. This new PE is surprisingly simple and can be used in various fields of acoustics and physics. It can be implemented numerically with minimal modifications to existing Crank-Nicholson PE solvers described in Section 11.2 of Ostashev and Wilson, Acoustics in Moving Inhomogeneous Media, Second Edition (2015).
Learning coordinate systems for fast and accurate acoustic modeling
Authors: Charous Aaron , Lermusiaux Pierre F.
Published: November 2022

Many popular numerical methods, such as finite difference and spectral methods, rely on simple domain geometry and environmental smoothness. Unfortunately, these features are rarely found in real-world simulations. We propose learning coordinate transformations with deep neural networks to facilitate acoustic modeling in complex media. Using automatic differentiation, we obtain new coordinate systems by solving various optimization problems that map the computational domain to a rectangular grid. Different choices of the objective function are utilized to attain different goals, including (i) mapping complicated boundaries such as the seafloor to straight lines and (ii) reducing the rank of two-dimensional slices of the refractive index. The first choice allows for domain decomposition to accurately model sharp discontinuities in density and sound speed. The second drastically accelerates a non-intrusive reduced-order modeling technique referred to as the dynamical low-rank approximation. Using realistic ocean test cases, we compare the performance of our learned coordinate systems with domain decomposition to the classic approach of smoothing sharp discontinuities, and we compare full-rank, low-rank, and coordinate-system-accelerated low-rank solutions of the three-dimensional parabolic wave equation.
Directivity of the muted trumpet
Authors: Avila Joseph E. , Bellows Samuel D. , Leishman Timothy W. , Gee Kent L.
Published: November 2022

The directivity function of a played musical instrument describes the angular dependence of its acoustic radiation and diffraction about the instrument, musician, and musician’s chair. In this study, high angular resolution directivity data were acquired in an anechoic chamber of a muted trumpet being played by a seated musician. The chair height and horizontal displacement ensured that the geometric center of the instrument’s radiating region fell at the circular center of a computer-controlled semi-circular array of 36 microphones positioned at Δθ = 5° polar-angle increments. Azimuthal rotations progressed in Δφ = 5° increments, such that the measurements involved 2,521 unique positions over a sphere. Additional measurements at a position within the rotating reference frame facilitated post-processing. The musician played chromatic scales at each rotation position, and this process was repeated for straight, cup, and wow wow mutes in order to draw comparisons in the directivity patterns of each mute to the unmuted trumpet. Radiation behind the musician increased as a result of the mute, and mute-dependent changes to the directivity patterns primarily occurred above 1 kHz.
Imaging standing waves in the resonator of a flue organ pipe
Authors: Baquerizo Lucia , Fuse Quinn , Kellison Makayle , Moore Thomas R.
Published: November 2022

The acoustic standing wave inside a transparent flue organ pipe has been imaged using transmission electronic speckle pattern interferometry (TESPI). Optically imaging acoustic standing waves in a pipe requires sensing the pressure-induced change in index of refraction of the air, and imaging this change in index has been accomplished in the past using a variety of methods. However, the presence of the flowing air that is responsible for creating the sound of an organ pipe masks the optical effects attributable to the standing wave. We demonstrate that the optical effects of the standing wave can be separated from those of the flow by spectrally filtering high-speed TESPI images at acoustic frequencies. The resulting images show both expected and unexpected details of the standing wave inside an organ pipe. [Work supported by NSF through Grant No. PHY–2109932.]
Assessing community noise annoyance: Two decades of the international technical specification ISO/TS 15666:2003
Authors: Clark Charlotte , Gjestland Truls , Lavia Lisa , Notley Hilary , Michaud David , Morinaga Makoto
Published: November 2022

The robust assessment of noise annoyance is of key importance given that it is the most prevalent community response in populations exposed to environmental noise. In 1993, the International Commission on Biological Effects of Noise Community Response to Noise team began formalizing a standardized methodology for assessing noise annoyance, which resulted in reporting guidelines and recommendations later published as a Technical Specification (TS) by the International Standards Organization in 2003 (ISO/TS 15666: 2003). This TS, intended to inform the international community on the quantification of the exposure-response relationship between noise exposure and annoyance, has been in circulation for nearly two decades and has been updated in 2021 (ISO/TS 15666: 2021) by an international working group (ISO TC43/SC1/WG62). This paper reviews use of the 2003 TS, identifies common adaptations in use, and summarizes the revisions. Methodological issues arising from the use of the 5-point verbal and the 11-point numeric scale questions and the scoring of “highly annoyed” are discussed. The revisions are designed to encourage further standardization in noise annoyance research. This paper highlights research needs that if addressed would strengthen the methodology underlying the assessment of noise annoyance, including multidimensional assessments of annoyance.
Preliminary analysis of urban sound data and the correlation to public health using a mobile phone application
Authors: Riegel Kimberly A. , Resko Jody
Published: November 2022

Obtaining accurate community sound data that allows for the real time annoyance response can be challenging. A mobile phone application called Auditive was developed to collect health history, annoyance, and sound level data from the respondents on a community scale. A pilot study was conducted in the spring of 2022 where 60 respondents uploaded approximately 900 sound and annoyance measurements. To improve the functionality of the application, the preliminary study data were examined for trends and correlations as well as obvious technological and data issues. The type of respondent as well as the kinds of sound recorded were examined. Some basic correlations between factors will be presented. After a review of the data, some modifications of the application were made to improve the quality of the collected data. The second version of the app was launched in Fall of 2022, and data were recorded with a new set of respondents. Comparisons of the data quality and the impact of the improvements to the application were analyzed.
Urban air mobility community noise test planning
Authors: Rizzi Stephen A. , Scata, Jr. Donald S.
Published: November 2022

The term “advanced air mobility” has been adopted by NASA to describe safe, sustainable, affordable, and accessible aviation for transformational local and intraregional missions. By this definition, advanced air mobility includes both “rural” and “urban” applications including cargo and passenger transport missions, and other aerial missions (e.g., infrastructure inspection). There will be a range of aircraft types performing such missions, including small and medium unmanned aircraft systems (UAS), electric conventional takeoff and landing (eCTOL) aircraft, and electric vertical takeoff and landing (eVTOL) aircraft. Urban air mobility (UAM) is a challenging use case for transporting cargo and passengers in an urban environment and is a new opportunity for aviation that could revolutionize the transportation system. The National Aeronautics and Space Administration and the Noise Division of the Federal Aviation Administration Office of Environment and Energy have initiated discussions for planning UAM community noise test(s) at the end of this decade. This presentation discusses the test goals, candidate test objectives, and some of the activities needed in preparation for the test(s). It also draws distinctions between the type of study envisioned (observational versus staged) and between it and recent and planned studies on large fixed-wing transports and commercial supersonic transports.
NASA quesst mission—Community response testing plans
Authors: Coen Peter , Loubeau Alexandra , Rathsam Jonathan , Shah Gautam H.
Published: November 2022

The National Aeronautics and Space Administration (NASA) has made a commitment to deliver data to the International Civil Aviation Organization’s Committee on Aviation Environmental Protection (ICAO CAEP) defining community response to sounds from supersonic aircraft designed such that their sonic boom is replaced with a soft “thump” sound. The dataset will be a correlation of public perceptions of these sounds to the corresponding acoustic levels and will support efforts to develop international standards for permissible noise from supersonic overflight. The NASA Quesst mission is developing the X-59, a unique research aircraft capable of quiet supersonic flight, and will use the aircraft in a series of community overflight tests to measure acoustic levels of its “sonic thump” and related public response. This presentation will provide an overview of the Quesst mission, including X-59 development, acoustic validation, and community testing with a focus on the plans and technical goals for those community response tests. In addition, results of a NASA-sponsored international workshop on strategies and considerations for key aspects of the community test phase of the Quesst mission, including estimating noise exposure levels and conducting surveys to support the dataset development, will be briefed.
Derivation of a second-order acoustic wave equation in an air-saturated porous medium from a volume-averaged transport model
Authors: Lyons Gregory W. , Hart Carl R.
Published: November 2022

For propagation of high-amplitude acoustic waves in a rigid porous frame saturated by air, significant departures from a constant flow resistivity model have been observed. This departure can be modeled as a quadratic modification to the linear Darcy’s drag law, known as Forchheimer’s correction. To study the physical cause and relative significance of this nonlinear correction with respect to convective nonlinearity, a second-order acoustic wave equation is derived from volume-averaged equations of mass, momentum, and entropy conservation. Due to the scale separation between the wavelength and the porous structure, the particle velocity is approximated as the sum of irrotational macroscopic and incompressible microscopic fields. The porosity, tortuosity, and permeability are defined and incorporated into the macroscopic conservation equations. Porous drag terms are also derived in the macroscopic momentum equation for Darcy’s law and Forchheimer’s correction. Conservation equations for fluid parameter perturbations are obtained, and a second-order wave equation is derived. Dimensional analysis, in terms of the acoustic Reynolds number and Darcy number, describes the criteria for significant Forchheimer and convective nonlinearity. A case is obtained for a Westervelt-like equation for approximately progressive plane waves. These results inform modeling of nonlinearities for sound propagation in porous media under practical conditions.
Laser-based resonant ultrasound spectroscopy in samples with compliant boundary conditions
Authors: Cherry Matthew , Adebisi Rasheed , Pastrana Juan , Giannuzzi Syndey , Lesthaeghe Tyler , Torres Reyes David
Published: November 2022

Laser-based resonant ultrasound spectroscopy (LRUS) is a promising technique for measuring elastic properties in samples of exceedingly miniature sizes where traditional piezoelectric transducers present a limitation. However, the performance of an LRUS system is highly dependent on the geometry and boundary conditions of the specimen. More specifically, samples manufactured from a substrate, such as micro-pillars, have a compliant boundary at the base which needs to be accounted for. In this work, sub-millimeter, free-standing rectangular parallelepipeds were manufactured from tungsten material. These samples provided excellent measurements of resonances as well as mode shapes. A similar pillar was manufactured and left attached to the tungsten block to study the outcome due to alterations on boundary conditions. The results show a significant attenuation on all signal content in modes with higher frequency than the fundamental bending resonance. However, excellent images of mode shapes were obtained once the sample was detached from the substrate. Furthermore, silicon cantilevers were manufactured from wafers, and similar effects were observed. The theoretical justification for poor performance in higher-order modes resulted in sample redesigns that provided superior fidelity resonance measurements.
Underwater resonant mode excitation using cavitation
Authors: Gupta Ankush , Cops Mark J. , Holt R. Glynn
Published: November 2022

Characterizing underwater objects is often accomplished with optical imaging, but this task is rendered difficult or impossible if the water is turbid or the object is encrusted or buried. Often imaging is capable of identifying approximate dimensions, but lacks the ability to differentiate between naturally occurring and manmade objects. However, every resonant target possesses its own (nearly) unique ID: its vibrational modal spectrum, if it can be excited. This study reports on the use of strongly collapsing cavitation bubbles, generated via dielectric breakdown, to impulsively excite resonant modes of an underwater object. [Work funded by Department of the Navy.]
Processing of linguistic and indexical information in adult cochlear implant users
Authors: Tamati Terrin N. , Moberly Aaron C.
Published: November 2022

Normal-hearing (NH) listeners simultaneously make use of both linguistic (speech content) and indexical (talker-specific) information in speech perception. For adult cochlear implant (CI) users, limitations in the talker-specific details conveyed by their devices may impact processing dependences between linguistic and indexical information. The current study examined the extent to which linguistic and indexical information are processed interdependently in adult CI users, using speeded phoneme and talker gender classification tasks. Higher-performing adult CI users (open-set word recognition >65% correct) reported the target vowel (phoneme classification) or target talker gender (gender classification). The non-target dimension varied by the number of talkers (phoneme classification) and the number of words (gender classification). Largely consistent with NH findings, adult CI users displayed asymmetric interference between linguistic and indexical dimensions. Phoneme classification was less accurate and slower with high talker variability. In contrast, gender classification was not affected by word variability. Processing dependencies also varied across individual CI users and related to auditory and cognitive-linguistic abilities. These preliminary findings suggest that adult CI users may make use of degraded linguistic and indexical information during speech processing. However, the extent to which they do so may depend on individual auditory and cognitive-linguistic factors.
Spatial cues on normal hearing and cochlear implant simulation with different coding strategies
Authors: Amelia Ria R. , Arifianto Dhany
Published: November 2022

Cochlear implant users are known to have limited access to spatial cues. This study investigated the perception of spatial cues in normal-hearing listeners and cochlear implant simulation users. Perception of spatial cues is assessed for performance in determining the direction of the sound and understanding the speech. The results show that cochlear implant simulation users still have access to spatial cues, just like normal- hearing listeners. Normal-hearing listeners and cochlear implant simulation users can perceive spatial cues in ILD and ITD. Both can accurately identify the direction of the sound (slope ≈ 1.00 and of set ≈ 0.00°). Cochlear implant simulation users can understand sentences as well as normal-hearing listeners (PCW = 113.64 rau) by using the coding strategy SPEAK in all channels or CIS with channel above 8. Perception of spatial cues in normal-hearing listeners and cochlear implant users can be improved by listening with two ears and spatially separating the target-masker position. The largest improvement in spatial cue perception was obtained from the head shadow effect (normal-hearing (NH) = 12.96, cochlear implant simulation users (CI) = 59.02), followed by binaural summation (NH = 5.72, CI = 19, 86) and binaural squelch (NH = 3.76, CI = 7.66).
Ultrasonic methods for the characterization of additively manufactured 316L stainless steel
Authors: Williams Colin L. , Shokouhi Parisa , Lear Matthew H. , Donahue Carly , Montgomery Colt J.
Published: November 2022

This research utilizes linear and nonlinear ultrasonic techniques to establish a linkage between microstructure and macroscale mechanical properties of additively manufactured (AM) stainless steel 316L samples. The specimens are manufactured using two methods: laser-powder bed fusion and traditional wrought manufacturing. Using the nonlinear ultrasonic method of second harmonic generation, the acoustic nonlinearity parameter is estimated in samples with different heat treatment levels intended to alter microstructural and mechanical properties. Linear ultrasonic parameters including wave speed and resonant frequency are additionally measured. Mechanical properties are obtained through tensile testing of coupons corresponding to the test samples. Microstructural information for the samples is obtained using electron backscatter diffraction to help elucidate the relationships between microstructure, mechanical properties, and ultrasonic response. Results indicate correlations between the nonlinearity parameter and both ultimate tensile strength and yield strength, where nonlinearity generally decreases as sample strength increases, particularly in the AM samples. We hypothesize that microstructural evolution of grain characteristics across different heat treatments influences trends in measured nonlinearity, as well as substructures at smaller scales such as dislocations. These results show promising evidence for the feasibility of AM parts qualification using nondestructive nonlinear ultrasonic testing.
Integrating ultrasound and x-ray computed tomography to evaluate the microstructure of binder jet stainless steel 316L components
Authors: Cook Olivia , Huang Nancy , Smithson Robert L. , Kube Christopher M. , Beese Allison , Arguelles Andrea P.
Published: November 2022

Binder jet printing (BJP) is a promising additive manufacturing method with benefits in sustainability, material selection, and geometric design freedom. However, issues related to part quality persist, necessitating reliable inspection and characterization strategies. Traditional protocols involving sectioning and extensive sample preparation may miss crucial information about a components’ microstructure due to volumetric variations. This study explores ultrasonic inspection of binder jet SS316L tensile specimens containing spatially varying grain size and porosity by measurement of longitudinal wave speed and attenuation. The ability of ultrasound to detect porosity is evaluated by cross referencing wave speed and attenuation data with porosity data gathered from x-ray computed tomography (XCT). Three-dimensional pore volumes were collapsed into two-dimensional maps such that ultrasound and XCT could be compared in a point-by-point fashion. After tensile testing, the location of failure was compared against wave speed and attenuation extremes. The results show the potential of ultrasound as well as important considerations related to the inspection of additively manufactured parts with complex microstructures.
Barriers to successful communication between healthcare providers and patients
Authors: Bent Tessa , Baese-Berk Melissa M. , Ryherd Erica E. , Manley Natalie
Published: November 2022

Effective communication between healthcare providers and patients is crucial for optimal health outcomes yet barriers exist that may decrease successful information transfer. In this talk, we provide an overview of our research program that brings together two central challenges for provider-patient communication: the acoustic environment and the linguistic characteristics of the speech. We describe a corpus of medically-related sentences, varying in their frequency and familiarity characteristics. We evaluated the intelligibility of these sentences in quiet, speech-shaped noise, and hospital noise for both young and older adults. Results demonstrated that combining low familiarity words with any noise source causes steep word recognition declines for both listener groups, and that older, but not young, adults had more word recognition difficulties in hospital noise compared to speech-shaped noise. In the future work, we are extending these studies to investigate comprehension and recall of orally presented health information for different populations (e.g., nonnative speakers) under a range of conditions (e.g., audio-visual, speakers wearing masks). These investigations integrate research on hospital soundscapes with foundational concepts from the speech perception literature to address a crucial real-world context. [Supported by IU Institute for Advanced Study and James S. McDonnell Foundation.]
Active structural acoustic control using the weighted sum of spatial gradients method
Authors: Sommerfeldt Scott D. , Blotter Jonathan D. , Aslani Pegah , Cao Yin
Published: November 2022

Active structural acoustic control focuses on implementing vibration-based control on a structure with the objective of achieving attenuation of the radiated acoustic field. It has been shown that utilizing control metrics that are integrally associated with the desired control result will generally lead to greatly improved control results. The weighted sum of spatial gradients (WSSG) method has been developed to provide global attenuation of the acoustic field radiated from a structure. It utilizes multiple spatial gradients that form the control metric, and which are correlated with various radiation mechanisms associated with the structure. The WSSG method will be briefly overviewed and the implementation of the method will be discussed. It will also be shown that the method is related to the concept of acoustic radiation modes, which have been used to describe radiation from structures. The WSSG method has been applied to several types of structures, and both computational and experimental results will be shown for flat plates and cylindrical shells to demonstrate the effectiveness of the control method.
Overview of the seabed characterization experiment
Authors: Wilson Preston S. , Knobles David P.
Published: November 2022

The seabed characterization experiment (SBCEX) is a multi-disciplinary, multi-institutional international research project devoted to the following scientific goals: (1) to understand the physical mechanisms that control acoustic propagation in fine-grained sediments, (2) to quantify uncertainties in the estimation of seabed parameters, (3) to correlate the observed horizontal variations in the acoustical field with the measured horizontal variability of the seabed, and (4) to assess the performance of the resulting geoacoustic models, inversions, and statistical inference methods. To facilitate these scientific goals, research cruises were undertaken in 2015, 2016, 2017, 2021, and 2022 primarily at a site known as the New England Mud Patch. The work of the project through 2019 was documented in a special issue of the IEEE Journal of Oceanic Engineering, Vol. 45, No. 1 that appeared in January 2020, as well as in peer-reviewed papers in other journals. Here a brief overview of the results through the 2020 special issue will be presented, as well as an overview of the new field work competed in 2021 and 2022. [Work supported by ONR.]
Direct measurements of acoustic and physical properties in mud and comparison to sediment acoustics models
Authors: Lee Kevin M. , Ballard Megan , Wilson Preston S. , Venegas Gabriel R. , Dorgan Kelly M. , Chaytor Jason
Published: November 2022

Sediment acoustics models relate seabed physical properties to acoustic wave speed and attenuation, and direct measurements of sediment acoustic and physical properties provide a means to test such models. We examine direct measurements from two field experiment sites with muddy sediments that contain different ratios of clay, silt, sand, and organic components, comparing the acoustic data with sediment acoustic model predictions using parameters obtained from cores as model inputs. In the New England Mud Patch, sediment sound speed profiles up to several meters below the seabed surface were measured using in situ acoustic probes mounted to a gravity corer. At a second site near Mobile Bay, in situ probe measurements of sound speed, attenuation, and shear speed were obtained in the upper 20 cm of sediment, and diver cores were collected and scanned with an acoustic core logger. Sediments from both sites were analyzed for porosity and grain size distribution. The applicability of various models to the mud found at each site will be discussed, as well as effects of infauna and organic matter, which were also measured, but are not explicitly included in the models. [Work sponsored by ONR.]
Sound isolation of recording studios
Authors: Hoover K. Anthony
Published: November 2022

Sound isolation to and from quality recording studios is critical to their success. Proper design based on informed understanding of both airborne and structureborne transmission is essential, because retrofitting isolation can be challenging or even prohibitive, and because one-size-fits-all recommendations may be unsatisfactory. This presentation will review some issues and evaluation methods that help to guide successful, cost-effective designs. Also discussed will be examples including a world-class studio with remarkable history that was encroached by an expanded loud facility, floated constructions that were not actually floated, and an approach that has helped to convince clients of the level of required isolation.
Anthropogenic sound sources in expanded southern resident killer whale critical habitat
Authors: Drappeau Emily N.
Published: November 2022

During the last decade, Southern Resident Killer Whale (SRKW) sightings in the Salish Sea have declined significantly. In 2021 NOAA expanded the critical habitat for SRKWs to include waters off of coastal Washington Oregon and California. As little is known about this territory, it is crucial to identify and understand potential threats. Underwater explosive sounds have been recorded and analyzed using passive acoustic monitors on the Washington Coast. These recordings were reviewed visually and aurally for key characteristics to determine their source. According to previously published descriptions, most of the approximately 16,500 sounds of high quality that were analyzed matched the characteristics of seal bombs, which are typically used in fishing operations to deter marine mammals. Using spatial and temporal sounds recorded in 2018 as a baseline, occurrences in 2019 and 2020 were further examined. Multiple lines of evidence have led us to believe that these explosions are associated with fishing, not military activity and are a potential threat to SRKW. It is this project's objective to continue to use published signatures to study the further changes. Passive acoustic monitoring is a vital mechanism in studying the emerging threats to SRKW outside the Salish sea.
Multi-frequency systems for arctic acoustic navigation and communications
Authors: Freitag Lee , Lee Craig , Gobat Jason , Singh Sandipa , Giaya Dennis , Gallimore Eric , Ball Keenan
Published: November 2022

Autonomous systems, including gliders, floats, and propeller-driven AUVs, require navigation under Arctic ice to be able to geolocate during their missions. In addition, acoustic communications provides for unidirectional or bidirectional data and command flow with the autonomous systems. Over the past ten years, steady progress has been made on implementing and demonstrating these acoustic systems in the Beaufort Sea north of Alaska. The eventual goal is a multi-frequency capability that uses 35 Hz for very long range navigation, 900 Hz for long-range navigation and communications, plus 10 kHz for close-range use. The different frequencies offer different advantages, and each is used accordingly. At 35 Hz, navigation transmissions span the water-column and survive reflection from the underside of the ice, allowing pan-Arctic ranges. The 900 Hz navigation and communications signals persist in the shallow (150 m) duct in the Beaufort at ranges up to several hundred kilometers, which is useful for under-ice survey transits. Finally, at 10 kHz, compressed data can be off-loaded and new mission files transferred via buoys on the ice. Recent work in 2021 and 2022 has continued to develop these capabilities, and this talk summarizes results and describes future directions.
Ice-tethered acoustic buoys for real-time active and passive monitoring in the Western Arctic
Authors: Turgut Altan , Schindall Jeffrey A.
Published: November 2022

Real-time monitoring of channel impulse response functions in the Beaufort Lens was performed by five Ice-Tethered Acoustic Buoys (ITABs) during March-September 2021. Each ITAB had an eight-element vertical line array and a 900-1000 Hz acoustic source, providing a reciprocal acoustic transmission of up to a 300 km range. Acoustic navigation of one ITAB was successfully tested using the acoustic travel-time from the other ITABs. In addition, a strong single arrival through the Beaufort Lens was observed on each ITAB. Simulations using the measured Q-functions [T. C. Yang, IEEE J. Ocean. Eng. 30(4), 865–880 (2005)] showed a reliable long-range acoustic communication through the Beaufort lens within the 900–1000 Hz frequency band. Finally, a passive ITAB was deployed in March 2022 to measure third-octave under/in-ice ambient noise in the Western Arctic. Both experiments showed that ITABs can be used for under-ice acoustic navigation and communication as well as real-time ambient noise measurements in the Western Arctic. [Work supported by the ONR.]
Double duct propagation in the Arctic
Authors: Baggeroer Arthur B.
Published: November 2022

Recent experiments in the Beaufort Sea encountered the “Beaufort Lens,” a hydrographic feature named by Russian acousticians, where warmer Pacific water enters the Bering Straits and rests above Atlantic water. This creates a “double duct” subsurface duct with this “lens” being near ubiquitous in space and time throughout the Beaufort. As part of the ONR Task Force Ocean program we found subsurface ducts in the Irminger Sea over the Reykjanes Ridge not reliably predicted by HYCOM. Propagation in these “double ducts” has some remarkable features and is well understood using normal modes and analogies to potential wells in quantum mechanics. These include the (i) filling of individual wells preferentially according to the modal phase speeds; (ii) tunneling phenomena when the phase speeds approaches the height of the potential barrier or maximum speed separating the ducts; (iii) issues of degeneracy when the modal phase speeds appear to cross; (iv) appearance of “mini convergence zones” for the transmission losses in each duct; (v) differences in modal group speeds with very small differences in phase speeds; and (vi) very low transmission loss when both source and receiver are in the subsurface duct separated from the water and/or ice surfaces.
My contributions to ultrasound metrology
Authors: Maruvada Subha
Published: November 2022

My work in ultrasound metrology has centered around developing pre-clinical testing methods for therapeutic ultrasound devices. These test methods include radiation force balance systems and methods specifically for high-intensity therapeutic ultrasound, time-delay spectrometry methods for measuring hydrophone sensitivity, acoustic characterization of tissue-mimicking material that has been approved as a medical device development tool and a comparison protocol of computational and experimental acoustic characterization for therapeutic ultrasound devices. The purpose of this work at the FDA is to develop bench testing methods to ensure proper review of medical ultrasound devices to evaluate device safety and performance. The test instruments and methods developed have helped promote the development and recognition of voluntary consensus standards, as well as FDA industry guidance, that can provide the basis for least-burdensome data collection requirements by manufacturers and allow the FDA to assess device safety and effectiveness in a more consistent, methodical and scientifically rigorous manner.
Graduate studies in acoustics at Northwestern University
Authors: Bradlow Ann , Cole Jennifer , Goldrick Matthew
Published: November 2022

Northwestern University has a vibrant and interdisciplinary community of acousticians. Of the 13 ASA technical areas, 3 have strong representation at Northwestern: Speech Communication, Psychological and Physiological Acoustics, and Musical Acoustics. Sound-related work is conducted across a wide range of departments including Linguistics (in the Weinberg College of Arts and Sciences), Communication Sciences & Disorders, and Radio/Television/Film (both in the School of Communication), Electrical Engineering & Computer Science (in the McCormick School of Engineering), Music Theory & Cognition (in the Bienen School of Music), and Otolaryngology (in the Feinberg School of Medicine). In addition, The Knowles Hearing Center involves researchers and labs across the university dedicated to the prevention, diagnosis and treatment of hearing disorders. Acoustics research topics across the university include speech perception and production across the lifespan and across languages, dialects and socio-indexical properties of speech; sound art and design; social and cultural history of the sonic world; machine processing of music; musical communication; auditory perceptual learning; auditory aspects of conditions such as concussion, HIV, and autism; neurophysiology of hearing; and the cellular, molecular, and genetic bases of hearing function. We invite you to visit our poster to learn more about the “sonic boom” at Northwestern University!
Graduate education and research in architectural acoustics at Rensselaer Polytechnic Institute
Authors: Xiang Ning , Braasch Jonas
Published: November 2022

The Graduate Program in Architectural Acoustics has been constantly advanced from its inception in 1998 with an ambitious mission of educating future experts and leaders in architectural acoustics, due to the rapid pace of change in the fields of architectural-, physical-, and psycho-acoustics, and noise-control engineering. Since years the program’s pedagogy using “STEM” (science, technology, engineering, and mathematics) methods has been proven to be effective and productive, including intensive, integrative hands-on experimental components that integrate architectural acoustics theory and practice. The graduate program has recruited graduate students from a variety of disciplines including individuals with B.S., B.Arch., or B.A. degrees in Mathematics, Physics, Engineering, Architecture, Electronic Media, Sound Recording, Music and related fields. Graduate students under this pedagogy and research environment have been succeed in the rapidly changing field. RPI’s Graduate Program in Architectural Acoustics has since graduated more than 120 graduates with both M.S. and Ph.D. degrees. Under the guidance of the faculty members they have also actively contributed to the program’s research in architectural acoustics, communication acoustics, psycho-acoustics, signal processing in acoustics as well as our scientific exploration at the intersection of cutting edge research and traditional architecture/music culture. This paper illuminates the evolution and growth of the Graduate Program.
Graduate programs related to acoustics at the University of Minnesota
Authors: Oeding Kristi , Whiteford Kelly L. , Nelson Peggy , Lim Hubert H. , Bee Mark A. , Oxenham Andrew J.
Published: November 2022

The University of Minnesota (UMN) has graduate programs that span the areas of Animal Bioacoustics, Psychological and Physiological Acoustics, and Speech Communication. Degrees are offered in Psychology (PhD), Speech-Language-Hearing Sciences (MA in speech-language pathology, AuD, and PhD in speech-language-hearing sciences), Biomedical Engineering (MS and PhD), Ecology, Evolution, and Behavior (PhD), and Neuroscience (PhD). Faculty across departments have a shared interest in understanding how the ear and brain work together to process sound and in developing new technologies and approaches for improving hearing disorders. Located on campus is the Center for Applied and Translational Sensory Science (CATSS), which provides opportunities for interdisciplinary collaborations across departments and industry to understand how sensory impairments work. Within CATSS is the Multi-Sensory Perception Lab, which houses shared equipment, including eye trackers and electroencephalography. The Center for Magnetic Resonance Research houses several ultrahigh field magnets, while the Center for Neural Engineering and affiliated faculty labs also house multiple neuromodulation and neurorecording devices to interact with and monitor neural activity in humans and animals.