bluuebunny/crossref_metadata_2025 huggingface dataset:
Advancing towards automatic speech recognition of children innaturalistic preschool environment
Authors: Dutta Satwik , Irvin Dwight , Hansen John H.
Published: November 2021

The preschool classroom is a viable space for capturing young children’s interactions with teachers. Developing speech/language assessment tools will offer a non-invasive way to quantify child-teacher interactions, allowing teachers to make changes as needed and better support children’s speech, language, and cognitive skills. Building Automatic Speech Recognition (ASR) systems for child speech has been challenging, since most studies have been conducted: (1) with older children, (2) in clean and controlled settings, and (3) generally are limited to prompted or read stimuli. To date, limited research has focused on developing ASR systems for spontaneous child speech in preschool settings. For our study, spontaneous child-teacher conversations were captured in preschool classrooms using the LENA digital audio recorder. A 25-h corpus of child speech were used for experiments using an open-source ASR toolkit. Major challenges in this data for developing ASR models include noisy background environments, age and diversity of children. Our effort focuses on alternative time-delay neural networks (TDNN) for acoustic modelling to improve ASR, as well as trade-offs in language model development and lexicon/vocabulary partitioning. Results from this study across acoustic and language models will be presented using child preschool classroom data. [Work sponsored by NSF CyberLearning Grant #1918032.]
Autoregressive power law noise for testing of signal processing algorithms
Authors: Taft Benjamin N.
Published: November 2021

Signal detection algorithms should often be tested in the context of noise with different “colors,” or exponents, of power law noise (PLN). These noise colors range from “red” (when the frequency exponent is –2), through “white” (0), to “blue” (2). Noise synthesizers that use autoregressive (AR) functions are particularly useful because they can be parameterized to generate the full range of PLN “colors.” The degree, or number of terms, in the AR generator for any color of PLN may be infinite. In practice, there are theoretical caps on the degree for some exponents, and diminishing returns for increasing the degree for others. The point of diminishing returns can be identified with two parameters: first, the size of the data vector being generated, and second, the user's tolerence for deviations between the realized power law and the desired exponent. The presentation will describe an open-source Python package, pypowerlawnoise, for generating PLN. This package demonstrates quantitative decision rules for choosing the degree for a discrete AR generator of PLN. A second Python package will be used to demonstrate how artificial PLN can be used to demonstrate the usefulness of a signal processing technique. The whifter package uses frequency-domain Fourier smoothing to isolate whistles and harmonics from background noise. It can also be used for source-filter analysis of speech. Using pypowerlawnoise to create test conditions, I quantify how whifter's efficacy changes across different background noise regimes.
Trans-dimensional geoacoustic inversion on a range-dependent track: Using chirp subbottom survey data as prior information for seabed layering
Authors: Bonnel Julien , Dosso Stan , Knobles David P. , Wilson Preston S. , Potty Gopu R. , Miller James H. , Lin Ying-Tsong , Goff John A.
Published: November 2021

Geoacoustic inversion methods can be broadly divided into two categories. Fixed-dimensional methods are based on the assumption of a known environmental parametrization, including the number of seabed layers. Trans-dimensional (trans-D) methods estimate the environmental parametrization as part of the inverse problem. Although trans-D methods are very powerful, they have barely been applied in range-dependent geoacoustic inversion, and fully range-dependent trans-D inversion is a challenging problem. To mitigate this issue, we propose to use chirp subbottom survey data as prior information within a trans-D inversion method. To do so, the method considers the seabed as an unknown number of homogeneous sediment layers; the number of layers and geoacoustic properties within layers are constant over range, but layer interface depths are range dependent, with the lateral variation informed by the two-way travel-times to reflectors from the chirp survey. The method was successfully applied for single hydrophone geoacoustic inversion using data collected during the 2017 Seabed Characterization Experiment. [Work supported by the Office of Naval Research.]
Deep ocean sound speed profile estimation using matched autoproduct processing
Authors: Johnson Jay R. , Dowling David R.
Published: November 2021

Sound speed profile (SSP) estimation from acoustic measurements alone in ocean environments is often a highly undetermined problem. Many methods have been developed which match arrival times or acoustic pressure observations to estimate a reduced-order SSP described with shape functions or empirical orthogonal functions (EOFs). These EOFs are commonly derived from multiple in situ measurements. This presentation describes an alternative method that matches autoproduct fields to invert for deep ocean SSPs without knowledge of the source waveform. The inverted SSPs are parameterized with EOFs derived from synthetic SSPs extracted from HYCOM (hybrid coordinate ocean model). This method is developed and illustrated using simulated long-range deep-ocean propagation data for frequencies in the 100s of Hz. The technique is also assessed with measured propagation data from the PhilSea10 experiment. [Sponsored by ONR]
Matched-field geoacoustic inversion using Gaussian Processes for field prediction
Authors: Michalopoulou Zoi-Heleni , Gerstoft Peter
Published: November 2021

Matched-field geoacoustic inversion is the process of maximizing a correlation measure between received data at deployed hydrophones and replica fields calculated via an acoustic model for a set of values for environmental parameters, frequently along with source range and depth. The values that produce the maximum correlation form the geoacoustic parameter and source location estimates. Matched-field inversion performance improves as the number of receiving hydrophones increases and the water column is sampled in a dense manner. In order to achieve dense water column sampling when only a few phones are available, we predict the field at a large number of virtual depths within a given aperture using Gaussian Processes. Similarly to classical matched-field inversion, the predicted field, computed after the choice of a suitable kernel and its hyperparameters, is correlated with replicas calculated at the same phone depths. It is demonstrated with both synthetic and real data that the Gaussian Process matched-field inversion approach outperforms conventional processing. The effect is more pronounced as the Signal-to-Noise Ratio attains lower values. [Work supported by ONR.]
Applications of semi-supervised learning methods in underwater acoustics
Authors: Acree Mason C. , Neilsen Tracianne B. , Knobles David P.
Published: November 2021

Research on supervised deep learning methods have shown potential for ocean acoustic applications. Supervised methods require labeled data samples for training. However, ocean acoustics data often do not contain labels. In experimental situations it is possible to estimate source range and speed labels as inferred by GPS data, but the environmental labels may not be easily defined. Applications of machine learning in ocean acoustics will be greatly enhanced by developing ways to utilize semi-supervised learning. In other applications, semi-supervised learning has been accomplished via contrastive learning or self-attention methods. Our work applies semi-supervised learning by developing a contrastive learning framework for acoustic data. First the model does self-training using an augmentation policy on unlabeled data to initialize representations of key features in the data. Then a small set of cleanly labelled samples are given to a model for supervised learning to teach the desired prediction task. Our work in contrastive learning will be applied to transiting surface ship spectrograms to demonstrate the effectiveness for predicting source labels and seabed type. Preliminary work will be presented to illustrate the advantages of semi-supervised learning. [Work supported by ONR contract N00014-19-C-20001.]
Infering the characteristics of marine sediments from the acoustic response of a known object
Authors: Bottero Alexis , Sternini Simone , Kuperman William
Published: November 2021

The acoustic response of an object depends on the surrounding environment. We show here how to take advantage of a known elastic target located near the seabed to infer characteristics of marine sediment. The approach consists of several steps. First, the structural admittance matrix of the elastic object is determined (numerically or experimentally). Then, the Equivalent Source Method (ESM) coupled with a spectral representation of the Green's functions in stratified domains makes it relatively inexpensive in terms of computational time to predict the object acoustic signature in various environments and experimental configurations. The resulting solver takes into account all multiple scattering between target (buried or not), sea floor and sea surface and is not limited to short distances. After presenting the solution to the forward problem we then show several synthetic inversions for sediment characteristics.
The whale song translation project—An experiment to assess humpback whale response to voice-selected visual feedback cues
Authors: Pines Howard S.
Published: November 2021

To better understand the behavioral and communication capabilities of Megaptera Novaeangliae, the findings of a recent whale song study suggest an intriguing experiment to assess humpback whale response to acoustically selected visual-feedback cues. The analysis of high-complexity, frequency-modulated song units indicates a Shannon-Hartley-compliant sub-unit architecture similar to human vowel generation. Like constant-pitch English language vowels, which are differentiated by their two most energetic peak resonance frequencies, humpbacks also exhibit precision vocal control of the production of a variety of sub-units of distinct and differentiable harmonic frequency combinations. Humans navigate mobile phone and tablet-PC informational, gaming, and adaptive learning apps using visual feedback from tactile-selected touchscreen icons and hyperlinks. In lieu of tactile manipulation, an alternative approach to touchscreen control is vocal selection of icons and links corresponding to the generation of specific vowel resonance frequencies and sub-unit harmonic frequencies. A software prototype of a voice-controlled “touchscreen” gaming experiment demonstrates how humans and humpback whales could conceivably interact or how humpbacks could engage in informational transactions. The prototype also incorporates video “training” examples designed to guide subjects in the voiced selection of visual symbols assigned to the sub-regions of a big-screen display.
Physics of flatulence
Authors: Ancalle David S. , Finn Charles L. , Jiang Nelson , Stewart Seth A. , Hu David L.
Published: November 2021

Flatulence consists of intestinal gas expelled through the anus. While flatulence is a common part of daily life, sudden changes can be important disease indicators for physicians. In this combined experimental and theoretical study, we rationalize the duration and acoustic frequency of flatulence among mammals, from rats to elephants. We perform high-speed videography and acoustic recordings of guinea pigs, humans, and whoopee cushions. The acoustic frequency is generated by the vibration of the skin of the anus, similar to the buzzing of lips in a trumpet’s mouthpiece. Thus, larger animals generate lower acoustic frequencies due to the lower resonant frequencies of the thicker and larger anal skin.
Just around the corner: Acoustic mirroring enables echolocating bats to detect occluded objects
Authors: Allen Kathryne , Fu Miao , Farid Christopher , Moss Cynthia F.
Published: November 2021

The ability to detect salient targets and segregate them from background clutter is a key function of sensory systems. The echolocating bat Eptesicus fuscus is an ideal model for investigating the influence of clutter on target detection, as they must navigate dense foliage at high speed, while tracking moving prey. This difficult task requires bats to reliably detect and track objects in the environment despite changes in distance, angle of view, and interference from background echoes, which obscure targets from sonar “view” and creates barriers bats must navigate around. Counterintuitively, recent studies reveal that environmental clutter echoes may improve performance under some conditions. Neurophysiological recordings in the bat inferior colliculus indicate that acoustic scattering caused by foliage can improve target discrimination when the separation between target and clutter is ∼20 cm. These findings suggest that acoustic reflections from clutter may provide additional “glimpses” of targets and improve target discrimination. Here, we test the ability of echolocating bats to make use of acoustic mirrors from clutter objects for target detection using a yes/no behavioral assay inspired by Non-Line of Sight Imaging experiments. Much like technology employed by machine imaging, robotics, and self-driving automobiles, we test the potential for bats to “see around corners” using only echoes reflected from objects in the environment to locate a target hidden behind an occluder.
Novel modeling of ultrasonic wave propagation in ophthalmic tissue
Authors: Ghorayeb Sleiman R.
Published: November 2021

Ultrasound has been widely used to diagnose a variety of anomalies present in ophthalmic tissue (detached retinas, tumors, cataracts, etc.), and to obtain a number of measurements in the eye like intraocular length, lens thickness, and so on. However, there has not been a clear understanding of how ultrasonic waves propagate and interact with the layers of the eye, and whether safety concerns are an issue. This presentation discusses two novel modeling techniques to complement these already existing tools to enhance ultrasonic evaluations of the eye by providing additional insight and a theoretical frame of reference. Axisymmetric finite element and PSpice transmission line models simulating a single-element transducer based on Redwood’s version of Mason’s equivalent circuit, a focusing lens, and a multi-layered medium that mimics propagation of ultrasound in the different layers of the eye are presented. Results are obtained for a normal eye and for one in the case of a retinal detachment. A-scans are also obtained in vitro using an extracted normal sheep’s eye for comparison. Both sets of results clearly show the transmission and reflection of the ultrasonic waves as they travel through the layers within the eye structure and confirm the validity of these modeling techniques.
Geoacoustic inversion for a 14-km autonomous underwater vehicle survey on the Malta Plateau
Authors: Sonnemann Tim , Dettmer Jan , Holland Charles W. , Dosso Stan
Published: November 2021

We consider signal processing and inversion of 1487 source instances recorded on a towed array along a 14-km seabed survey on the Malta Plateau. The data were acquired by autonomous underwater vehicle (AUV) and processed as reflection coefficients versus grazing angle and frequency. Data acquisition caused several artifacts that are studied by various data representations. These representations expose periodic fluctuations of reflection coefficients with angle and frequency that do not depend on seabed location. Averaging over source instances, frequencies, and angles reduces the artifacts. The Bayesian inversion assumes a one-dimensional seabed structure for each data set and is parametrized by an unknown number of homogeneous layers, sound velocities, densities, and attenuations. Results from individual inversions and sequential Monte Carlo sampling are compared. We demonstrate that removing data artifacts reduces over-fitting problems from previous considerations of the same data. Comparisons to piston and gravity core estimates, and separate wide-angle data show good agreement with the AUV results for two locations along the track. However, results at greater depths exhibit high uncertainty and strong influence of chosen prior boundaries. When considering results for all 1487 data sets, dipping and terminating layers are found along the track with high resolution (∼10 cm).
Vibro-tactile display for the visually impaired using miniature electrostatic transducers
Authors: Fullford Lillian , White Robert D. , Bernstein Jonathan
Published: November 2021

A vibro-tactile electronic display is being developed to aid the visually impaired community by increasing access to graphical and textual information. A high-density vibro-tactile arrayed display would improve the user experience while moving away from external displays on the market. We propose to use millimeter scale electrostatic transducers operating at frequencies well below resonance as candidate array pixel elements. Motion detectable by a fingertip, mechanical impedance of a fingertip, and frequency at which fingertips can detect contact were considered. Motion of 5μm with a fingertip touching the device and 10 μm without a finger touching the device is desired with the device at a mechanical impedance of 480N/m, which is twice the mechanical impedance of the fingertip (240N/m measured by Diller and Kyung). Transducer membrane thickness, force on the fingertip, and gap width are being optimized through prototyping and finite element analysis. A prototyped row of pixels was manufactured using 0.051 mm thick metalized Mylar film with an air gap of 0.02mm and a diameter of 1 to 2 mm per pixel, driven by AC electrostatics at 400 V peak to peak. Motion analysis is being conducted using a laser vibrometer. Preliminary results demonstrate motion of 10 μm peak to peak at low frequencies, with further analysis and optimization ongoing.
Exploring the effects of masks and instrument covers on air flow
Authors: Rollins Sydney , Hoffman Kurt R.
Published: November 2021

In this desperate time of COVID, can we still do the things we love safely? Efforts to keep schools safe for music rehearsals during the past academic year included singing with masks and covering various parts of musical instruments with cloth barriers to limit the flow of exhaled droplets into the air. We assembled a Schlieren system to test the effects of these different adaptations to modify the flow of air for different instruments, including the voice. This paper presents the results of our measurements and an assessment of their effectiveness at reducing or redirecting the flow of air. With the arrival of the Delta variant, new questions are being raised about safety and exposure due to the possibility of breakthrough infections. Therefore, we are revisiting these remediation methods to evaluate their potential effectiveness in light of changing safety risks.
Efficient digital waveguide synthesis of a pipe organ
Authors: Darabundit Champ C. , Smith Julius O.
Published: November 2021

The modern pipe organ can have as many as 10 000 pipes, each of which is a simple sound generator. In order to digitally synthesize a pipe organ, each pipe requires its own digital waveguide model due to its individual geometry and state. To complicate the matter, pipe geometry can vary greatly across different pipe organ ranks, pipes can be reed-driven or air-jet-driven, and it is possible for a single key to sound many ranks at once. As a result, developing an acoustic model of even a small pipe organ is intensive both in the modeling and in the computational demands for real-time synthesis. For modeling the pipes, we propose a scalable lossy digital waveguide framework whose parameters can be changed based on a pipe's geometric model. We utilize the Faust functional programming language to produce high-performance digital signal processing code.
Application of spectral proper orthogonal decomposition and resolvent analysis to periodically forced supersonic jets
Authors: Heidt Liam , Colonius Tim , Nekkanti Akhil , Schmidt Oliver T. , Maia Igor A. , Jordan Peter
Published: November 2021

The mechanisms by which near-nozzle forcing alters the turbulence structure and far-field sound of turbulent jets are not well understood. We perform large-eddy simulations of subsonic and supersonic axisymmetric isothermal turbulent jets subjected to an axisymmetric periodic forcing. The triple decomposition framework and spectral proper orthogonal decomposition are used to study the effect of the forcing on the underlying turbulence spectrum and determine how the periodic forcing alters coherent non-phase-locked structures. For subsonic jets, high-amplitude (1% of the jet velocity) low-frequency, Stf = 0.3, forcing is required to achieve a small change to the underlying turbulence spectrum and most energetic modes of the subsonic jet, despite producing a very energetic, phase-locked (tonal) response. The changes in the spectrum and the phase-locked structures are predicted well via resolvent analysis and linearized Navier-Stokes computations performed on the new turbulent mean, respectively. This suggests that there is little nonlinear interaction between the phase-locked structures and natural turbulence. High-frequency forcing, Stf = 1.5, shows similarly linear behavior except for around St≈0.75, which appears to be associated with vortex pairings triggered by the natural turbulence. Results of a similar analysis performed on a Mach 1.5 ideally expanded isothermal jet will also be presented.
Infrasound phase arrival uncertainty and seismoacoustic event location comparison
Authors: Koch Clinton , Dugick Fransiska , Berg Elizabeth , Albert Sarah , Peterson Matthew , Guzman Raquel
Published: November 2021

Using a catalogue of over 60 seismoacoustic events compiled for a diverse variety of source-types we estimate probabilistic locations using seismic and acoustic phenomena, both individually, and combined. Previous studies have shown that combining seismic and acoustic observations can improve location estimates under specific circumstances. By examining a wide variety of seismoacoustic arrivals we further explore the capabilities and limitations of seismoacoustic event locations. The size and shape of the confidence region associated with a given event location is dependent on pick and model uncertainty, thus, accurate estimates of these parameters are crucial. Errors in arrival time picking depend on the signal-to-noise ratio at the station and the arrival properties. Here, we employ an amplitude based bootstrapping approach to approximate a data driven pick uncertainty for infrasound arrivals. To account for simplistic atmospheric models, estimates of travel time variations using celerity predictions based on ground truth locations are used to obtain phase dependent model uncertainties as a function of distance. The resulting event locations are then statistically compared by source, arrival, and instrument type to demonstrate the applicability of seismoacoustic event location analysis under different circumstances. [SNL is managed and operated by NTESS under DOE NNSA Contract DE-NA0003525.]
Auditory figure-ground segregation is impaired by aging and age-related hearing loss
Authors: Boncz Adam , Szalárdy Orsolya , Velősy Péter , Winkler Istvan , Tóth Brigitta
Published: November 2021

Listening in a noisy environment relies on our ability to extract structure from noisy sensory input while segregating it from the rest of the scene (Figure-Ground Segregation—FGS). To assess whether FGS is impaired by aging, source localized brain activity was analyzed from young, older adults, and hearing-impaired (HI) elderly during object detection in noise. Listeners’ task was to report whether they detected a figure (rising sound stream) within either high or low noise. Individualized figure and noise levels allowed us to compare groups across the same performance levels (65% vs 85% accuracy). HI group was impaired in integrating sounds of the figures. Figures elicited an early sensory processing-related (object-related negativity- ORN) and a later perceptual decision-related (P600) brain response. In the elderly, compared to the young the ORN was delayed in general and smaller in the inferior frontal gyrus (IFG). P600 activity was generated within a less distributed network in both the elderly and HI relative to the young. In the HI, compared to the elderly the ORN was smaller in the auditory cortex and IFG. Our results suggest that early FGS processes are disturbed only neurally in the elderly and overtly in HI.
Mu-Net: Community-shared infrastructure for mobile underwater acoustic networks
Authors: Song Aijun , Hong Xiaoyan , Zhang Fumin , Peng Zheng , Wang Zhaohui
Published: November 2021

It is well recognized that there is a strong need for shared testbeds to promote research growth in underwater communities. We are developing an open-source, open-architecture, community-shared infrastructure for mobile underwater acoustic networks, namely mu-Net. The overall goal is to support research and education in the joint communities of underwater signal processing, communications, networking, and robotics. The mu-Net infrastructure consists of three main components: an indoor testbed, a lake testbed, and underlying open-architecture software. The mu-Net software uses a service-oriented architecture to interface with open-access autonomy suites, such as MOOS-IvP and ROS. Functions associated with sensing, communication, networking, vehicle behaviors, and navigation are compartmentalized as modular service units. The indoor testbed is developed for lab tests with a moderate number of nodes, for example, eight nodes, for deployments in a swimming pool. The lake testbed uses two commercial autonomous underwater vehicles (AUVs) that can be deployed in a lake. We will provide shared access to both testbeds for data collection and algorithm validation. We will present the software architecture, hardware instruments, and the obtained acoustic measurements from the testbeds.
Infrasound from orbital space vehicle launches
Authors: Olausson Samuel A. , Bassett Michael S. , Houston Griffin , Mathews Logan T. , Anderson Mark C. , Durrant J. T. , Hart Grant W. , Gee Kent L.
Published: November 2021

Launches of medium and heavy-lift space vehicles produce high-amplitude, broadband noise environments with significant infrasound. Measurements taken at Vandenberg Space Force Base during Falcon 9 and Delta IV Heavy launches allow for a comparison of infrasound between rockets and environments. For the Falcon 9, low surface wind and high signal-to-noise ratios allowed for the observation of infrasound all the way through main engine cutoff. In contrast, the Delta IV Heavy measurements featured much higher surface winds and lower signal-to-noise ratios. However, even during the Delta IV Heavy measurement, infrasound was recorded for several minutes after liftoff. Characteristics as a function of distance and time are discussed.
Designing and building low-cost infrasound sensors to enable a large-N sensing array
Authors: Audette William (Chip) , Brooks Chris , Talmadge Carrick , Frazier Garth , Waxler Roger M.
Published: November 2021

Industrial and commercial pressure sensing elements have continued to improve in performance while also dropping in price. In this paper, we present our approach to designing and building infrasound sensor nodes using these off-the-shelf sensor elements. We then built a 50-node array and demonstrated its use in the field. Calibration results for the sensor nodes and initial field results are presented. With the feasibility of this approach demonstrated, we iterated the design of the system based on lessons-learned from the field experience. We fabricated a 300-node array to the revised design. System performance and cost are presented.
Bridging cultures with acoustical materials research
Authors: Haberman Michael R.
Published: November 2021

This talk will provide a short overview and insights associated with the education and early career of the author over the past two decades and how his experiences with different cultures, both social and professional, has influenced scientific advancements. This will include a short overview of formal education in both the United States and France and professional growth as a researcher at the Applied Research Laboratories at The University of Texas at Austin (UT) and then as a professor in the Department of Mechanical Engineering at UT. The talk will highlight research done in each context and how those experiences have improved outcomes in scientific and personal contexts.
The Seattle Space Needle renovation: Acoustical design considerations and challenges at 600 ft above ground level
Authors: Bruck Daniel C. , Penzell Jaimie
Published: November 2021

Built for the 1962 Seattle World’s Fair as a symbol of humanity’s Space Age aspirations, the Seattle Space Needle is one of the most recognizable landmarks in North America. In September 2017, construction commenced for “The Century Project,” a renovation project designed to reveal the tower’s internal structure while expanding and improving its views. This presentation will discuss the acoustical design criteria for the two levels of all-glass, circular observation levels, as well as design approaches for reverberant sound control, sound isolation for key areas, and mechanical system noise control for a proposed fine dining restaurant at the “Loupe” level. The presentation will also include post-construction measurements and several photos during construction and at project completion.
Masking escape in killer whales, stereotypical call design as a noise impact reduction strategy
Authors: Yurk Harald , O'Neill Caitlin , Burnham Rianna , Morrison Christie , Vagle Svein
Published: November 2021

Killer whale call repertoires appear to remain relatively stable over generations because call design is considered socially transmitted between generations. Transmission errors during learning may be responsible for new call designs and repertoire size increases. Call and repertoire divergence may also be the result of adaptation to noisy environments. Temporal and spatial ambient noise variation occurs naturally in killer whale habitats and spans across the auditory frequency ranges of calls. Call components that vary in peak energy across frequency bands appear to escape auditory noise masking because peak amplitude variation per frequency is part of the stereotypical design of calls. As a result level variations in the noise spectrum rather than broadband noise dose may be the more relevant noise impact metrics for calls. Killer whale call design and repertoire divergence appears to reflect the naturally occurring variability in propagation of different frequencies. This may have led to repertoire variation among different populations allowing them to explore different acoustic niches. Presented are preliminary results from an ongoing study into call design influences on signal propagation under varying ambient noise conditions at different times of the year and different geographic locations and water depths within resident and Bigg’s killer whale habitat.
Passive acoustic monitoring of Southern Resident Killer Whales: Occurrence, residency and movement data in support of conservation
Authors: Gavrilchuk Katherine , Burnham Rianna , Vagle Svein , Shaw Jesslynn , Rannankari Lynn , Smyth Dylan , Woodley Erin , Thornton Sheila J.
Published: November 2021

Passive acoustic monitoring (PAM) of cetaceans offers valuable spatio-temporal information on presence and residency time to support population management and recovery strategies. Acoustic detections can be used to evaluate diel and seasonal occurrence patterns when visual detection opportunities are limited (e.g., night or winter), and acoustic encounter duration can inform habitat use patterns (e.g., travelling/shorter duration vs foraging/longer duration). Additionally, detection data from strategically placed recorders may also be used in the development of predictive movement models. Here we use PAM data to evaluate critical habitat use by the Endangered Southern Resident Killer Whale (SRKW) population in Juan de Fuca Strait and the Salish Sea, near the southwest coast of Vancouver Island, British Columbia. Continuous recordings were collected at three locations from May to October, 2018–2020, and used to assess presence and acoustic encounter duration. As this area experiences significant commercial vessel traffic and recreational vessel use, mitigation of risk from acoustic disturbance is a high priority for recovery. These PAM detection and encounter duration data were used to provide advice for management actions in support of SRKW recovery in Canadian Pacific waters.
Information extraction, scalable processing, open-source development, and community engagement: Data science in fisheries acoustics
Authors: Lee Wu-Jung
Published: November 2021

The past decade has seen an explosion of the availability of fisheries acoustic data, driven primarily by the successful integration of echosounder on a variety of ocean observing platforms and a broader adoption of active acoustics as a tool for ocean sensing. However, we are just at the cusp of creating data processing techniques and workflows that can truly transform these data into information. In this talk, I will discuss recent advancements in multiple areas that I believe when combined, harbor the potential to accelerate research progress in fisheries acoustics toward making revolutionary changes: integration of physics-based models and data-driven methods, including machine learning; cloud computing; open-source software development; interoperable data and data standards; and community engagement, which plays a crucial role in driving rapid exchange of ideas and spurring innovation in not only fisheries acoustics, but also the broader oceanography and geoscience fields.
Applying deep learning to imaging sonar for the automated detection, classification and counting of untagged fish in fish passages
Authors: Kandimalla Vishnu , Richard Matt , Smith Frank , Steig Tracey W. , Whidden Chris , Nealson Patrick A.
Published: November 2021

The Ocean Aware project, led by Innovasea and funded through Canada’s Ocean Supercluster, is developing the next generation of underwater observation systems to transform fishing, aquaculture, and marine energy. One facet of this project is developing innovative methods for real-time tracking of untagged fish and species at risk around man-made infrastructures, such as hydropower dams, that present barriers to fish passage. The system is based on applying modern Deep Learning techniques to automatically detect and classify fish and their species from high resolution imaging sonar. In this paper, we present our results from applying adaptations of the widely used YOLO machine learning model to detect and classify multiple species of fish from a public dataset containing eight distinct species of fish from the Ocqueoc River captured by a high resolution DIDSON imaging sonar. Our results demonstrate that deep learning models can indeed be used to detect, classify species, and track fish using high resolution imaging sonar. Although there has been extensive research in the literature identifying particular fish, such as eel versus non-eel and seal versus fish, to our knowledge this is the first successful application of deep learning for classifying multiple fish species with high resolution imaging sonar.
On relieving aging vocalizations of famous trot singers by sound massage
Authors: Bae Myungjin , You Kwang-Bock
Published: November 2021

Most of the songs of famous trot singers sing folk songs of sorrow, and their popularity has continued for decades. However, aged singing voices feel flat and monotonous compared to the loud singing voices of their prime. In order to improve aging vocalizations, it is sometimes used to calm the mind and body through ingestion of a tonic or neck massage. However, as the singing voice ages, the spectrum bandwidth gradually decreases, and the chords of the voices become simpler, so listeners do not feel the magnificence of the songs well. In this paper, a new method of relieving the aging characteristics of famous singers through sound massage of sound mug cups is proposed. In other words, based on the past vocalizations of famous trot singers, the singing spectrum was restored in its prime by reflecting the singing waveform from the mug cup and massaging the inner epithelium of the vocal cords. Although the bandwidth of a famous trot singer's voice has been reduced by –27% for 30 years when the proposed sound cup massage is applied, the aging spectrum is restored by more than 90% compared to the heyday, and most of the chords in the song come to life.
Preliminary report on the effect of room acoustics on choral performance in Notre-Dame and its pre-Gothic predecessor
Authors: Mullins Sarabeth , Le Page Valérie , De Muynke Julien , Canfield-Dafilou Elliot K. , Billiet Frédéric , Katz Brian F.
Published: November 2021

The study of acoustics as intangible cultural heritage is an active field of research with implications beyond the scientific community. This study examines the influence of the acoustics of the new Gothic cathedral of Notre-Dame de Paris on the medieval singers who pioneered a style of plainchant known as the School of Notre-Dame using interactive virtual acoustic environments (VAEs) and real-time auralization. The experiment compared the approximated acoustics of the prior cathedral (torn down in 1163 CE to make room for Notre-Dame) with Notre-Dame which partially opened in 1182 CE. A speculative VAE of the pre-1163 cathedral was created by modifying a calibrated model of an extant and contemporaneous Roman basilica, while the early Notre-Dame VAE was generated by time-regressing a calibrated model of the modern cathedral to match its earlier state. A choir specializing in historically informed performance practices was studied as they sang Organum Purum and Organum Notre-Dame inside the VAEs of the pre-1163 cathedral and the early cathedral of Notre-Dame de Paris. Musical parameters were extracted from the recordings to examine what influence the different architectures may have had on musicians’ performances.
Neural plasticity for music processing in young adults: The effect of transcranial direct current stimulation (tDCS)
Authors: Adodo Eghe , Paterson Cameron , Yu Yan H.
Published: November 2021

Transcranial direct current stimulation (tDCS) has increasingly been proposed and utilized as a unique approach to enhance various communicative, cognitive, and emotional functions. However, it is not clear whether, how, and to what extent, tDCS influences nonlinguistic processing such as music processing. The purpose of this study was to examine cortical responses to music as a result of noninvasive brain stimulation. We used a passive listening multiple oddball paradigm consisting of sixtypes of music pattern changes (rhythm, intensity, slide, location, pitch, and timbre) and recorded the event-related potentials (ERP) using 65-electrode sensor nets. Healthy young adults were tested before and after transcranial direct current stimulation (tDCS). We hypothesized that short-duration one-session tDCS would enhance some aspect of music processing. Our results indicated that the differences between pre- and post-tDCS ERPs were only evident in some conditions. Noninvasive brain stimulation, including tDCS, has the potential to be used as a clinical tool for enhancing auditory processing, but further studies need to examine how experimental parameters (dosage, duration, frequency, etc) influence the neural responses for auditory processing.
David T. Blackstock: Scholar, teacher, mentor, and gentleman
Authors: Hamilton Mark F.
Published: November 2021

David T. Blackstock was born in Austin, Texas in 1930. After earning B.S. and M.S. degrees in physics at University of Texas at Austin he spent two years at Wright-Patterson Air Force Base, where he developed an interest in acoustics working under Henning von Gierke on hearing protection. He then joined F. V. Hunt’s group at Harvard University and earned a Ph.D. in applied physics in 1960 with a doctoral thesis in nonlinear acoustics, ultimately his lifelong passion. Following three years at General Dynamics and seven years at University of Rochester, David returned to UT in 1970 to join its Applied Research Laboratories, and in 1987 he became Professor of Mechanical Engineering. Among David’s legacies is his formulation of a convenient framework for implementing weak-shock theory. Combining analytical, computational, and experimental approaches, he proceeded to investigate acoustic saturation, finite-amplitude noise, suppression of sound by sound, parametric array in air, sonic boom, therapeutic ultrasound, and other fundamental problems in nonlinear acoustics. David was widely known as an exceptionally caring man, whether bringing Soviet scientists and their research to the attention of the West, teaching and mentoring graduate students, or through extensive service in the ASA and International Commission for Acoustics.
David Blackstock and the physics of nonlinear sound beams
Authors: Muir Thomas G. , Hamilton Mark F.
Published: November 2021

In the 1970s, David Blackstock and his students and colleagues examined nonlinear sound beams both theoretically and experimentally. Two noteworthy articles in JASA resulted from this research, one by Shooter, Muir and Blackstock (1974) and another by Lockwood, Muir and Blackstock (1973). Of particular interest was the generation of highly directive radiation at harmonics of the source frequency that at moderate source levels decreased in beamwidth with harmonic order. Additional sidelobes were also observed in the harmonics. The main lobe in both the fundamental and the harmonics eventually broadened with increasing source level as shock waves were formed. Eventually finite-amplitude absorption became significant, acoustic saturation set in, and the medium did not permit further increase in amplitude. David’s application of weak-shock theory to model this process was validated by underwater acoustic experiments at the Applied Research Laboratories Lake Travis Test Station involving transducers driven at high intensities, at several hundred kilohertz, with waveforms and beams measured at ranges of several hundred meters. The results provided guidance for many applications, ranging from audio frequency tools in ocean acoustics to ultrasonic biomedical instruments now used worldwide in diagnostic and therapeutic applications. [Work supported by ARL:UT.]
Spatial acoustic processing with a laser distance sensor using a Tympan device
Authors: Sarkar Kanad , Corey Ryan M. , Singer Andrew C.
Published: November 2021

We will produce a setup for source localization experiments utilizing laser distance sensors with the Tympan device. The Tympan will allow us to perform on-device post processing, improve the portability of our experimental setup, and potentially reduce the electrical noise in our data. We demonstrate the benefits of this device through localizing an acoustic source through lasers placed at different points in space and comparing the Tympan setup to our previous setup.
Fuzzy structure theory, statistical energy analysis, and resonant-frequency-distribution of internal mass
Authors: Pierce Allan D.
Published: November 2021

The present talk gives a historical perspective on two early and relatively little- known papers having to do with fuzzy structure theory. The first is a letter to the editor by Lyon titled “Statistical energy analysis and structural fuzzy” (JASA 1995). The second paper is a slightly later 1997 Journal of Vibrations and Acoustics (ASME) article titled “Resonant-frequency-distribution of internal mass inferred from mechanical impedance matrices, with application to fuzzy structure theory.” The present paper seeks to clarify and qualify Lyon's statement, “It appears hat the fuzzy structure theory of structural interaction is highly compatible with the SEA framework.” The second paper clarifies the concept of modal mass and gives a proof that, for a lightly damped closed mechanical system, you can express the mechanical displacement fiield as a sum of natural modes. With each natural mode, one can associate a fixed amount of mass. The mass, moreover. is additive and sums to the total mass of the system. The idea goes back to some earlier work (1963) of Cunniff and O'Hara of the U. S. Naval Laboratory. The theory leads to the concept of modal mass per unit natural frequency bandwidth, and leads to a justification for the SEA assumption that interactions are between motions of natural modes with comparable natural frequencies.
Asymptotic behavior of the added damping effect of a fuzzy substructure and the importance of modal overlap
Authors: Russell Daniel A. , Sparrow Victor W.
Published: November 2021

The theory of fuzzy structures was introduced by Christian Soize in 1986 as a means of predicting the average vibroacoustic behavior of complex structures with imprecisely known internals. The damping and mass loading effects of a fuzzy internal substructure, modeled by random 1-dof oscillators, are analyzed through a boundary impedance. The Pierce-Sparrow-Russell and Strasberg-Feit models of fuzzy structures simplify the mathematics involved and concentrate on the physical concepts behind the added damping and mass loading effects of the internal substructure. Both models contain a problematic step in which a discontinuous impedance sum is replaced with a smooth integral. This paper explores the asymptotic behavior of the impedance sum in the limits of a large number N of attachments and small attachment damping ζ in order to determine the viability of this step. Modal overlap plays a crucial role, since half power points of individual attachment resonances overlap for small ζ when the density of attachments is high enough or for fewer attachments when the damping of individual attachments is high enough. It is found that the impedance sum sufficiently approaches the integral limit when Nζ ≧2. [Work originally sponsored by ONR.]
Energy flow, connectivity and entropy in the light of fuzzy structures
Authors: Carcaterra Antonio , Akay Adnan
Published: November 2021

Fuzzy structures, as presented in the literature, refer to a dynamic coupling between a master and a population of slave resonators of uncertain characteristics. However, the investigation of such systems opened new perspectives looking at the way energy flows between the two components, the masters and the slaves. New elements, not originally included into the concept of fuzzy, have been subject of investigations (Carcaterra-Akay, JASA, JSV) disclosing relevant questions: how the topology of connectivity between master and slaves affects the energy transfer? Can be a thermodynamic analogy established between fuzzy structures and thermal systems? Can entropy gain a role in structural dynamics, as it plays a key role in thermodynamics? This paper makes a historical reconstruction of these puzzling questions related to fuzzy structures.