bluuebunny/crossref_metadata_2025 huggingface dataset:
Broadband noise characteristics of fans with different blades under identical working conditions
Authors: Xu Tianyu , Huang Bohua , Hu Ying , Huang Lixi
Published: November 2023

Small axis-flow fans are widely used for air cooling and ventilation systems. A common small axis-flow fan has an unshrouded rotor, structs or stator vanes and a round casing. The fans used in this work are designed based on isolated-airfoil blade design mode and simple radial equilibrium theory supplemented by three-dimensional flow simulations with steady flow. The noise radiated from the fan can be decomposed to discrete tones and broadband noise, which is mainly due to interaction between blades and structs or stators vanes and turbulence, respectively. Under the working conditions of the same pressure rise and volume flow rate, the noise spectra from different fans are analyzed. It is found that with the addition of the fan blade number, the concentration of the broadband sound energy gradually shifts from low frequency to high frequency. And the fewer the number of blades, the less the corresponding total broadband energy. Besides, the calculation results also show the fan with more blades can be absorbed more sound by the same sound absorption materials with the same volume. The findings are useful for improving the acoustic design of small axis-flow fans.
Auditory reality and evaluation of hearing-aid function
Authors: Wolters Florian , Herrlin Petra , Larsson Josefina , Smeds Karolina
Published: November 2023

Knowledge about people’s auditory reality (AR), i.e., the variety of listening demands and environments experienced in everyday life, is crucial when developing and evaluating hearing-aid function. We have previously investigated AR of older people with impaired hearing and generally seen an “easy” AR (many reports of passive listening and focused listening to TV, mainly in quiet). In the current study, we included participants with both normal and impaired hearing to investigate if participants with impaired hearing are avoiding difficult situations. The EMA study ran for a week with six daily prompts. In addition to the EMA survey items from our previous study, sound levels were recorded, and avoidance was investigated in an exit interview and by analyzing differences in AR between the groups. Preliminary analyses show that there were differences between the two groups in terms of where they were when they responded. The differences in listening task were small, but the participants with impaired hearing rated the reported situations to be more difficult than the normal-hearing participants. Our new results will be presented together with a discussion about the consequences of our auditory reality data on the way we evaluate hearing-aid function.
Speech intelligibility and hearing aid benefit in a living room: Comparison of real and simulated acoustics
Authors: Schütze Julia , Ewert Stephan D. , Kirsch Christoph , Kollmeier Birger
Published: November 2023

For hearing-impaired patients, a disparity between hearing aid benefit determined by conventional audiological assessment and observed in everyday life has been reported. Hence, ecologically valid testing methods to better reflect performance in real-world scenarios are required. Hereby, the living room is a highly relevant (home) environment for speech communication involving various target and interfering sources. This study examines speech intelligibility in an average German living room with a connected kitchen and acoustic reproductions of the real room using loudspeakers. Speech recognition thresholds were measured using the Oldenburg Sentence Test (OLSA) and a male-transformed version of the ISTS (International Speech Test Signal) as a masker. Aided and unaided hearing-impaired listeners, as well as a normal-hearing control group, participated. Three target positions were investigated, with the most challenging target position in the adjacent kitchen with an obstructed direct sound path. Interactive room acoustics simulation (allowing for head movements) was used to replicate the living room via a small-scale (four) loudspeaker array, as applicable in the clinical environment, and a large-scale, three-dimensional array with 86 loudspeakers. The study discusses the impact of room acoustics on speech intelligibility at different target positions and the relationship between real and simulated environments regarding hearing aid benefit.
The Listen to Learn for Life (L3) assessment framework
Authors: Mealings Kiri , Miles Kelly , Kan Alan , Ibrahim Ronny , Buchholz Joerg M.
Published: November 2023

Listening is the primary gateway for children to learn in the mainstream classroom, but the dynamics and noise of modern classrooms can make listening challenging. This is especially true for children with hearing loss, language and communication difficulties, attention deficits, autism, other learning needs, and/or those communicating in a language other than their native language. It is, therefore, critical for researchers to realistically assess how children listen to learn in the classroom and to understand how listening can be improved to enhance children’s learning and wellbeing. The Listen to Learn for Life (L3) assessment framework is a tool to use when conducting this research which holistically incorporates frameworks from health, speech and hearing sciences, and education sectors. The L3 assessment framework has three main components: characterisation of activity (perceptual setting of lecture, group work, or individual learning activity), functioning assessment (hearing, listening, comprehending, or communicating), and impact (learning and wellbeing). These are affected by External and Internal Influences. Here, we present selected examples of how to apply the framework to assess children’s listening, learning, and wellbeing during different classroom activities as well as determine the effectiveness of a chosen intervention.
Language processing speed in school students with hearing loss: A review
Authors: Holt Rebecca , Smith Trudy , Leigh Greg
Published: November 2023

For effective learning in classroom settings, it is critical that students comprehend spoken and written language rapidly. If language processing is slow, children may miss content in lessons, struggle to participate effectively in group work, and be disadvantaged in high-stakes assessment tasks. Rapid language processing may be challenging for students with hearing loss using hearing aids or cochlear implants. They may process language more slowly than peers with normal hearing due to either contemporaneous signal degradation from their hearing devices, or “fuzzy” mental representation of language resulting from degraded input during language acquisition. A better understanding of language processing speed in students with hearing loss is urgently required to provide the basis for appropriate classroom support strategies and provisions in assessment tasks. This review of the current state of knowledge on language processing speed in school-age children with hearing loss will demonstrate that while some research does find slow language processing at the word and sentence level in this population, this may be modulated by factors including task difficulty and degree of hearing loss. Priority areas for future research, including processing speed at the paragraph/discourse level and the relationship between spoken and written language processing speed, will also be highlighted.
Analysis of distributed active noise control systems
Authors: Zhao Sipei
Published: November 2023

Active noise control technology has witnessed a great success in the past decades for local noise control in headsets and similar devices. However, many challenges are yet to be tackled for active control of noise over a large spatial region, where multichannel systems are needed. One of the significant issues is the high computational complexity of multichannel adaptive algorithms running on a centralized processor. To overcome this problem, distributed and decentralized adaptation strategies have been proposed to spread the computational burden over multiple processors recently. This paper will review existing distributed and decentralized active noise control systems based on the filtered-reference least mean square algorithms and analyze their convergence behavior under a unified framework. The convergence conditions in the mean and mean-square sense are studied and the transient and stead-state mean square errors are also analyzed. Simulations are performed to verify the proposed framework and analysis. This work will provide insights into current distributed active noise control systema and shed light on developing new algorithm design in the future.
A virtual sensing method based on plane-wave assumptions for active noise control headrests
Authors: Yoshimatsu Toma , Shinobu Naoki , Itou Hiroaki , Kozuka Shihori , Kamado Noriyoshi , Haneda Yoichi
Published: November 2023

Active noise control (ANC) headrests have been studied to suppress cabin noise and achieve a comfortable sound environment in public transportation mobility. To improve the suppression performance at the ear, this system requires virtual sensing technology to estimate sound pressure at the ear from microphone observations on the headrest. In this study, we propose a virtual sensing method for ANC headrests based on the assumption that noise arrives as plane-wave. The proposed method assumes that the cross-correlation between the observed signals of two adjacent microphones located on a grid point in space is constant and independent of absolute position. Based on this assumption, the cross-correlation estimated from observations between two microphones far from the ear is used to predict the noise propagation from the microphones near the ear to the ear. When noise reaches the ear first, the estimated cross-correlation becomes non-causal. To address this issue, we propose a method for predicting noise at the ear that involved removing pure delays in the impulse response of primary path estimated from observations of a reference microphone placed near the noise source and a microphone placed far from the ear. The effectiveness of the proposed method is demonstrated by computer simulation.
Shear wave effects in hydroacoustic recordings of the Comprehensive Nuclear-Test-Ban Treaty International Monitoring System
Authors: Zampolli Mario , Haralabus Georgios , Metz Dirk , Castro Alves Oliveira Tiago , Prior Mark K.
Published: November 2023

The hydroacoustic (HA) component of the Comprehensive Nuclear-Test-Ban Treaty Organization’s International Monitoring System (IMS) comprises six stations with triplets of moored hydrophones suspended in the SOFAR channel and five near-shore seismometer stations for T-phase detection. Understanding the conversion between compressional and elastic waves at the crust-ocean boundary or at large bodies of ice can contribute to better identification and association of arrivals. In this talk, examples recorded by the IMS HA network are presented with a view to stimulating discussion and further analysis: (i) T-phases from the September 2017 announced DPRK underground nuclear test recorded by the hydrophones of HA11 (Wake Island); (ii) a “precursor” southerly arrival at HA04 (Crozet Islands), associated with the hydroacoustic anomaly related to the loss of the Argentine submarine ARA San Juan, which is inter alia compatible with a Lamb wave propagating through the Antarctic ice-sheet; (iii) T-phases from earthquakes along the Nazca subduction zone scattered horizontally by the Juan Fernandez sea-mounts and recorded by HA03 (Chile); and (iv) conversion of signals from distant underwater explosions at the crust-ocean boundary near IMS T-stations. Benchmark studies to assess the accuracy of spectral element model setups previously used for scenarios (iv) would be particularly desirable.
Experimental study on the sound transmission loss suite at the University of Technology Sydney
Authors: Zhu Qiaoxi , Williams Paul
Published: November 2023

Sound transmission loss suites are essential testing facilities for measuring the sound insulation properties of building elements and assessing noise attenuation. However, inconsistencies in test results can arise due to variations in the size, shape, and construction of test rooms across different laboratories, with biases introduced by the room acoustics or acoustical environment of the facility itself. To evaluate the reliability of such testing, we conducted an experimental study on the sound transmission loss suite at the University of Technology Sydney. Our investigation focused on three key factors: estimating the maximum achievable sound reduction using a heavyweight wall installed at the test aperture on the source room side, testing the effectiveness of vibration isolation between reverberation rooms, and assessing the decoupling of the sound field within the reverberation rooms.
Laboratory measurements of thermal noise
Authors: Readhead Mark
Published: November 2023

An experimental study was undertaken of the aspect of underwater ambient noise which normally receives only a cursory reference—namely, thermal noise. A brief survey of the theory and literature, and consideration of how to separate amplifier noise from hydrophone noise, is followed by laboratory measurements on piston and spherical hydrophones. Results are presented of impedance and power spectral density measurements undertaken in water and other fluids. Measurements with the piston hydrophones were also performed as a function of distance from tank and water surface boundaries or from another hydrophone. The cross power spectral densities are presented as a function of separation distance between pairs of hydrophones. All hydrophones had their free field receive sensitivities and beam patterns measured, but the spectral densities have not yet been converted to pressures as the more interesting features are seen near resonances, where phase calibrations will also be required.
Blind-label acoustic subwavelength imaging
Authors: Ma Chu , Lin Jinuan
Published: November 2023

There is a long-existing tradeoff between the imaging resolution and the penetration depth in acoustic imaging caused by the diffraction limit. Most of the existing subwavelength imaging approaches that address this trade-off require exogenous “labels,” such as metamaterials or contrast agents, to be deposited close to the objects. Those labels need to either remain static or be tracked precisely during imaging, therefore, are extremely restrictive in practical applications. This talk will present our recent work on a “blind label” approach for acoustic subwavelength imaging. The “blind labels” are randomly distributed acoustic scatterers with deep-subwavelength sizes whose exact locations and trajectories are unknown. A hardware/software co-design framework is developed that is composed of two parts: 1) spatial mixing: a physical process that converts the originally evanescent components in the scattered waves from the object to propagating components that can reach the far-field detector; 2) computational image reconstruction. Our experiments both in air at KHz frequency range and in water at MHz frequency range achieved multi-fold resolution enhancement. The proposed “blind-label” approach relaxes the restrictions of depositing controlled labels close to the object, therefore significantly improving the practicality of acoustic subwavelength imaging in acoustic sensing, imaging, and communication applications.
Generative model-based transmission health monitoring of construction machinery in real factory
Authors: Di Hao , Li Xinpei , Oikawa Yasuhiro , Kiya Shoichi
Published: November 2023

In real factory production processes, transmission systems occasionally produce abnormal noises that deviate from their normal sound patterns. Detecting these anomalies is crucial for identifying the underlying causes and ensuring the quality of products. The traditional health monitoring of the transmission system in construction machinery relies on the expertise of skilled workers. In order to enhance detection capabilities during instances of abnormal noise occurrence, conserve human resources, and provide a technological foundation for future automation in production, we propose a transmission system sound detection method based on a generative model. In this study, normal transmission system sounds were collected from Komatsu Corporation using professional equipment, and log-Mel features were extracted from the raw audio data. The generative model was employed as a classifier and trained on normal transmission system sounds, with reconstruction error serving as the threshold to distinguish between normal and abnormal sounds. The experimental comparison with traditional deep learning methods verified the effectiveness of our approach. The results demonstrate the feasibility of applying the generative model as a classifier for health monitoring of the transmission system in Komatsu's construction machinery.
Machine learning predictive model for motor moise by expanding dataset using electromagnetic force characteristics
Authors: Jeong Wontae , Jeong Wontae
Published: November 2023

To understand the variations of electric vehicle motor noise, the electromagnetic force change due to the tilting and the eccentricity between the rotor and the stator on the noise should be studied. However, it takes enormous computation time to consider all the various conditions, so machine learning (ML) model that can reduce the analysis time of electromagnetic force and noise was developed. The developed ML model showed very high accuracy prediction performance with an R2 value higher than 0.99 even for data that was not used at all for training. The speed increase was more than 100 times of FE analysis. The authors doubt that the high accuracy of the developed model implies the potential for electromagnetic force data structure to be much simpler than it appears. Therefore, various analyzes were conducted on the force and uneven magnetic pull. The change in the temporal-spatial main frequency component was not large, and only the change in the side order was meaningful. It was confirmed that to create a predictive model using a smaller dataset for not only the UMP but also all the individual teeth force is possible. This new way of creating a training dataset for an ML model helps to increase the training efficiency. Based on the generated prediction model, it can be used to identify changes in noise characteristics in major rotational orders and derive suitable improvements.
Prediction and analysis of aeroacoustic characteristics of a real-size high-speed train running in open field using compressible Large Eddy Simulation and vortex sound source
Authors: Lee Kwongi , Cheong Cheolung , Kim Jaehwan
Published: November 2023

With the rapid advancement of technology, high-speed trains have been requested to increases their speeds. Aerodynamic noise generated from the external flow fields around these trains has become a critical factor to be addressed during a design phase. Accurate prediction of flow-induced noise in high-speed trains requires high-resolution sound source generation in the near-field and precise noise propagation analysis in the acoustic field without numerical dissipation. This necessitates the appropriate design of grids, taking into account aerodynamic noise generation and propagation in conjunction with the length scales of the relevant components of a real-size train. To tackle this challenge, the present research employs a three-dimensional compressible Large Eddy Simulation (LES) technique with high-resolution grids to simultaneously calculate the external flow and acoustic fields of a real-size high-speed train consisting of five cars running in an open field. A comprehensive analysis is conducted to evaluate the contributions of major components, namely, a cap, pantograph, bogie, intercoach, and HVAC cover, which are well-known as significant contributors to high-speed train flow-induced noise. The study utilizes the vortex sound source approach to analyze the generation mechanism of flow-induced noise for each component, providing valuable insights that could potentially aid in reducing aerodynamic noise.
A procedure for obtaining forecast turbulence parameters in the atmospheric boundary layer for acoustic propagation
Authors: Doebler William , Loubeau Alexandra
Published: November 2023

Propagation through turbulence causes a mean reduction in loudness of sonic booms and in some cases can cause significant fluctuations in loudness about that mean. Understanding these effects is important for accurately planning loudness levels during upcoming community noise tests with the X-59 aircraft as well as mitigating the risk for excessive loudness due to turbulence. Current methods for modeling acoustic propagation through turbulence require several atmospheric parameters including the atmospheric boundary layer (ABL) height, friction velocity, mixed-layer velocity scale, surface-layer temperature scale, as well as ambient pressure, temperature, and humidity within the ABL. Accurate forecasts of these parameters are needed for X-59 flight planning and may also be useful for planning future supersonic aircraft certification flight tests. This presentation showcases one method for obtaining the forecast turbulence and ambient atmospheric parameters from freely available Climate Forecast System Version 2 data. Forecast parameters are compared to measurements to assess accuracy and utility.
Low-frequency acoustic collimated beam
Authors: Pantea Cristian , Davis Eric S. , Greenhall John
Published: November 2023

In recent years, we have developed a variety of unique acoustic sources that can generate a highly collimated acoustic beam (very low beam spread) of low frequency (10-250 kHz) without any side lobes. An acoustic beam with the above characteristics is extremely important and leads to deeper penetration, due to low frequency, and increased lateral resolution, due to collimation. These novel acoustic sources are based on frequency mixing in nonlinear medium, linear array superposition, generation of Bessel-like acoustic beams through radial modes of piezo disks, etc. These sources were used extensively for wellbore integrity monitoring and fracture detection on simulated boreholes in the laboratory. A few different approaches of generating a Low-Frequency Collimated Beam, along with potential applications will be discussed.
A single crystal Lamb wave sensing array
Authors: Baddiley Eliza , Moss Scott , Vien Ben , Gray Jaslyn , Rajic Nik , Rosalie Cedric , Munk David , Szydzik Crispin , Mitchell Arnan , Chiu Wing
Published: November 2023

This paper reports on a multi-element relaxor ferroelectric single crystal (RFSC) based acoustic emission (AE) sensor called LAMDA (linear array for modal decomposition and analysis). This sensor is being developed foracoustic-signature detection applications, including for AE-based damage detection on space-based and undersea platforms. RFSC [011] Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (or PIN-PMN-PT) was machined into 200 μm thick × 1 mm long × 4 mm wide elements, with 16 of these elements arranged on a flexible-polyimide-carrier to form a LAMDA. This sensor was bonded to a 1.6 mm thick aluminium plate with dimensions 600 mm x 600 mm. Acoustic emissions consisting of Lamb waves (e.g., A0, S0) were generated in the plate using both piezoceramic (Pz26) disk-actuators and pencil lead breaks (PLBs). LAMDA measurements and one-dimensional laser-vibrometry were undertaken on the plate and compared with two-dimensional multi-physics model predictions. The plane-strain model geometry comprised a rectangular-section 1.6 mm thick and 600 mm long with a LAMDA located centrally. An AE, being a 5.5-cycle Hann-windowed function with centre-frequencies 300–1000 kHz, was introduced 150 mm from the LAMDA via point loading perpendicular to the surface. The Lamb wave dispersion-curves generated from the model showed good agreement with the experimental curves determined from LAMDA and laser-vibrometry.
Acoustic metasurface for perfect absorption using helmholtz resonators with non-uniformly partitioned cavities by membranes
Authors: Choi Eunji , Jeon Wonju
Published: November 2023

We propose an acoustic metasurface consisting of sub-wavelength Helmholtz resonators whose cavities are non-uniformly partitioned by membranes, aiming at perfect absorption of low-frequency sound with the aid of hybrid resonance. Compared to the existing unit cells based on Helmholtz resonators, the proposed ones with embedded membranes have lower resonance frequencies, which implies that it is possible to achieve perfect absorption of sound by using a thinner metasurface. This study provides a theoretical model for fast and accurate design considering the visco-thermal losses in narrow orifices and the higher-order modes of the membrane. By optimizing geometrical parameters and locations of the embedded membranes, we design the metasurface for perfect absorption based on the theoretical model. Experimental validation is performed in impedance tube via fabrication.
Identifying linguistic contributions to variable speech perception in Spanish/English bilingual children and adults using the ascending target-to-masker ratio method
Authors: Cowan Tiana , Buss Emily , Leibold Lori , Portillo Suresh , Olmstead Anne
Published: November 2023

When people encounter variable speech, like an unfamiliar accent, they map new productions to existing word forms. This skill appears to develop through adolescence for monolingual children, with school-age children perceiving unfamiliar accented speech less accurately than adults. For monolingual children, vocabulary size and phonemic awareness predict performance. Less is known about which factors account for individual differences in variable speech perception in multilingual school-age children. The goals of this study were to (a) assess group differences in variable speech perception in Spanish/English bilingual and English monolingual children and adults, (b) validate the ascending target-to-masker (TMR) method for assessing speech reception thresholds (SRTs) for foreign accented speech, and (c) identify linguistic skills that account for individual differences in performance. Participants completed speech perception and language testing. SRTs in speech-shaped noise were measured for Midland-, Spanish-, and Korean-accented English; these accents ranged from familiar to unfamiliar across participants. In each accent condition, one list of Bamford-Kowal-Bench test sentences was presented, with each sentence presented at multiple TMRs. Preliminary data suggest differences in how bilingual and monolingual groups perceive variable speech in noise. While linguistic skills accounted for individual differences in performance, different patterns emerged in children and adults.
Your brain on accents: Profiles of event related potentials in cross-dialectal listening in the US English context
Authors: Walker Abby , Zaharchuk Holly , Miller Adriana , Van Hell Janet
Published: November 2023

Behavioral studies have established that cross-dialectal communication is typically harder than within-dialect communication: listeners make more mistakes and are slower to respond to less familiar accents. In this study, we use event-related potential (ERP) analysis of electroencephalography (EEG) to capture the neurocognitive correlates of these patterns. Speakers of Mainstream US English from Western Pennsylvania (N = 23) participated in an auditory go-no-go task where they heard both Southern- and Mainstream-accented US English real and nonsense words (and were asked to respond to real, animal words). We see effects of accent for real words on the P200 and N400, reflecting more effortful processing in both the acoustic-phonetic and lexical-semantic stages for Southern versus Mainstream accents. We see no differences in nonsense word processing, and together, these findings suggest that the difficulty in normalizing Southern-accented tokens at the acoustic-phonetic level disrupted lexico-semantic access later on. We are currently running the same study with Southern-accented listeners in Southwest Virginia, to see whether we see inverse results or whether listeners with substantial exposure to both dialects (which we expect to be true of our Southern listeners) show different response profiles.
A directional spatial active noise control system with a sound field separation algorithm
Authors: Zhang Huawei , Zhang Jihui (Aimee) , Ma Fei , Sun Huiyuan , Samarasinghe Prasanga N.
Published: November 2023

Spatial active noise control (ANC) systems aim to control noise fields within the entire region of interest. However, current spatial ANC systems commonly lack the spatial selectivity to target a specific noise field from the whole noise fields, which cannot satisfy user requirements in some cases. This paper designs a directional spatial ANC system to control noise fields selectively based on the direction of arrival (DOA). The key idea is to introduce a DOA-informed sound field separation (SFS) algorithm to design the directional spatial ANC system. In detail, the directional spatial ANC system is designed to control noise fields selectively, with the ability to select the target sound field introduced by the SFS algorithm. Simulation results demonstrate that the designed directional spatial ANC system can control noise fields selectively within the region of interest in a noisy environment.
Manifestations of the weak shear rigidity of marine sediments in amplitudes and travel times of acoustic normal modes and lateral waves
Authors: Godin Oleg A.
Published: November 2023

Compressional-to-shear wave conversion at interfaces within unconsolidated marine sediments and interference of shear waves within thin sediment layers have been found to make significant contributions to sound attenuation [O. A. Godin, J. Acoust. Soc. Am. 149, 3586–3598 (2021)] and produce unexpectedly strong perturbations in the normal mode group speed even when the shear speed is small compared to the compressional wave speed. This paper extends the previous analysis to the lateral waves and their applications to characterize the compressional wave speed and attenuation in the seabed. Shear wave-induced contributions to horizontal refraction of normal modes over horizontally inhomogeneous seabed are modeled to characterize the bearing and travel time errors that arise in the fluid-bottom approximation. The acoustic travel time and amplitude effects of the shear waves are found to accumulate at different rates with the propagation range depending on the stability of the shear wave interference within the seabed. The ways to distinguish between the manifestations in acoustic observables of the weak shear rigidity in the seabed and the other environmental uncertainties are discussed for range-independent, range-dependent, and horizontally inhomogeneous shallow-water waveguides. [Work supported by ONR.]
Greater artistic and technological performance through the converged technologies of architectural acoustics, electroacoustic enhancement, and immersive audio technologies
Authors: Boot Tim , Roskam Frederic , Coleman Phil , Brown Simon , Laval Julien
Published: November 2023

Producing meaningful, creative, and engaging experiences for audiences requires highly integrated acoustics and audio technologies. The fields of architectural acoustics, electro acoustic enhancement and immersive audio technologies have converged, altering the way we approach entertainment venue design. Globally, demand has increased for immersive audio in live and reproduced sound, and electro acoustic enhancement technologies are becoming more widespread. We will discuss how architecturally integrated end devices, multi-function signal processing, and architectural acoustical design should be optimized to create next-generation performance venues. We will use a project example that integrates sound system, acoustic enhancement, and architectural acoustics, illustrating how increasing clarity in audience with acoustic enhancement and supporting the immersive audio increases audience engagement. We will show what can be improved to elevate the experience in a converged approach. The paper will illustrate how a convergence of audio technologies, infrastructure, and a unified design and engineering processes is creating far greater opportunities for artistic experimentation and expression.
Sound environment control using an immersive audio system—Advancing sound experience for creators and listeners using Active Field Control
Authors: Hashimoto Dai , Miyazaki Hideo , Bakker Ron , Kim Sungyoung
Published: November 2023

Spatial and immersive systems have gained popularity in recent years and are broadly used in various types of applications to realize natural or augmented sound environment. To create a variety of sound environment freely and flexibly, Yamaha immersive audio system, known as Active Filed Control (AFC), has two functions. One is “sound source control” based on object-based audio rendering technique and another is “sound field control” based on acoustic enhancement technology. This paper presents several unique solutions applying immersive audio systems that use either or both sound source control and sound field control. We conducted post-event acoustic measurements or survey of questionnaire supporting that intended acoustic controls had been successfully implemented.
Aerodynamic sound production from flying beetles
Authors: Allen John S. , O'Rourke Kevin
Published: November 2023

Extensions of previous research on the aerodynamic sound production by flying beetles are presented. The topic is of interest in terms of both fundamental acoustics and the applications such as classification and tracking of invasive insect species. High speed video with synchronous acoustics recordings of the Coconut Rhinoceros Beetle (Oryctes rhinoceros) and the Oriental Flower Beetle (Protaetia orientalis) provide experimental data for the analytical and numerical models. Three dimensional, unsteady flow simulations were conducted using compressible flow software (CAESIM, Adaptive Research, Inc.) with a TVD methodology. Flapping wing motion requires mesh deformation with a rotation with a prescribed bending and also coupled rotation and translation of the wing’s hinge position. Contributions of wing beat frequency and vorticity to sound generation are examined with respect assumptions of the spatial dimensions (two or three dimensional), bending and fluid structure interactions. Underlying sound generation mechanisms at the wing tips are examined in higher fidelity. Both hovering and forward flight are investigated and compared in terms of the different flapping motion of the two species. In addition, relationships of the tones to the temporal lift and drag lift coefficients are highlighted.
A tale of whale and fiber: monitoring baleen whales with Distributed Acoustic Sensing (DAS)
Authors: Bouffaut Léa , Klinck Holger
Published: November 2023

Distributed Acoustic Sensing (DAS) converts fibers in existing underwater telecommunication fiber-optic cables into dense listening arrays of strain sensors. Recent advances in DAS interrogating technology enable increasing data quality, spatial coverage, and bandwidth, sparking interest in applied environmental sensing. Initially focused on seismic data collection, e.g., for earthquake monitoring, DAS has demonstrated abilities in detecting waterborne acoustic sources, including the low-frequency sounds of blue and fin whales (Balaenoptera musculus and B. physalus) over tens of km of fiber. DAS is instrumented from land, collects data in near-real time, and offers region-wide spatial coverage. Thus, this technology provides a unique opportunity for robust monitoring of endangered and threatened migratory baleen whales at ecologically meaningful spatial and temporal scales. This talk will introduce our research on using DAS to monitor low-frequency baleen whales, including detection and tracking, and the open-access DAS4Whales python package, developed to analyze terabytes of spatio-temporal data collected with DAS. We will also address the potential limitations of this new monitoring technology and provide a roadmap for further research and testing needed to exploit the technology's full potential.
Toward translating novel imaging biomarkers from preclinical to clinical settings
Authors: Hwang Misun
Published: November 2023

Microvascular imaging of the neonatal brain is now feasible with the advent of ultrasound technologies that enable detection of slow flow in smaller vessels. As an advancement from conventional Doppler, microvascular imaging (MVI) technique has been applied in neonatal brain ultrasound scans to better understand how anatomic and functional changes of cerebral microvessels relate to disease diagnostics and prognosis in the neonatal brain. This lecture will introduce about the technique, current and emerging applications of MVI, as well as challenges and future directions of advancing cerebral microvascular markers of neonatal brain health. Some of the invasive methods used to study cerebral physiology and biomarkers in high-fidelity preclinical models are difficult to directly test and validate in vulnerable neonates. As such, this lecture will open up the forum for future directions on how the scientific and medical fields can come together in advancing the clinical validation and integration of novel imaging biomarkers to improve neonatal brain health.
Detection of cerebral ischemic injury during extracorporeal membrane oxygenation using microvascular flows measured by ultrasound localization microscopy
Authors: Zhang Zeng , Hwang Misun , Freeman Colbey , Sultan Laith , Haddad Sophie , Kilbaugh Todd , Katz Joseph
Published: November 2023

Pediatric Extracorporeal Membrane Oxygenation (ECMO) is a life-saving therapy. Affecting 8–50% of patients, brain injury is among the most frequent complications. Non-invasive monitoring of brain perfusion during ECMO using contrast-enhanced ultrasound imaging can potentially improve the outcome. Here we utilize an in-house developed Ultrasound Localization Microscopy (ULM) procedure, which involves a super-resolution deep learning approach for subpixel localization of microbubbles and Kalman filter-based bubble tracking, to measure the brain blood perfusion in a pediatric pig model during ECMO. Parameters, including the mean velocity magnitude in large (>1mm) and medium (0.2–1 mm) vessels, as well as the cerebral microcirculation for micro (<0.2 mm) vessels, are analyzed and compared with the histological readings of brain ischemic injury levels. Data show significantly reduced micro perfusion in the cortex and thalamus with increasing levels of ischemic injury. Compared with large and medium vascular flows, microvascular flows are more sensitive in not only detecting injury but also evaluating injury levels. These results suggest that the management of ECMO patients could be guided by and benefit from the non-invasive monitoring of cerebral microvascular flows.
The history and prehistory of Asian free reed instruments
Authors: Cottingham James
Published: November 2023

The free reed pipes and mouth organs are among the most significant indigenous musical instruments of East and Southeast Asia. The origin and development of these instruments involve the history and prehistory of a multitude of ethnic groups. The basic principles of operation and construction of the free reed are simple, and it seems likely that similar instruments may have had multiple places and times of origin. A number of examples of these instruments, ranging from very simple to fairly complex. These include mouth resonated lamellophones, a single free reed coupled to a bamboo pipe or buffalo horn resonator, a reed pipe with multiple s finger holes, and multipipe mouth organs. These instruments have traditionally been constructed with very simple tools using natural materials, primarily bamboo and wood. Bamboo is often still used for the reeds as well as the pipes, although metal reeds have been common for some time.
Sound radiation from semi-infinite elliptical ducts with uniform subsonic jets: An analytical approach
Authors: Wang Ruichen , Huang Xun
Published: November 2023

This paper presents an analytical method for modeling the acoustic field radiation from a semi-infinite elliptical duct with a uniform subsonic jet. Elliptical ducts are often used as inlets for turbofan engines to take full advantage of the pre-compression effect of the fuselage and improve the stealth performance of the aircraft. The method accounts for the instability wave inside the vortex sheet induced by the shearing of jet and ambient flow and its effect to sound radiation. The method uses Mathieu functions to describe the incident and scattered sound in the elliptic cylindrical coordinates. A semi-analytical Wiener-Hopf approach with low computational cost is applied to obtain the near and far field solutions. The near field is illustrated by acoustic pressure maps at different modes and circumferential angles. The far field is shown by directivity patterns at single tones. Numerical simulations based on a finite element method are conducted to validate the accuracy of the analytical method. The results show good agreement between the analytical and numerical solutions. The proposed method can be used to analyze the acoustic characteristics of elliptical ducts with jets, which are relevant for noise control and optimization of turbofan engine inlets.
High-speed observation of bubble and droplet dynamics under irradiation of 1-MHz ultrasound
Authors: Kudo Nobuki
Published: November 2023

Simulation techniques have resulted in significant progress in elucidating phenomena that are too fast and small for direct observation; however, there has also been considerable progress in the legacy techniques of direct observation. We have been studying applications of microbubbles for ultrasonically enhanced drug delivery, and in this presentation, we will introduce our results of high-speed observations carried out to elucidate the roles of microbubbles injected into the capillaries of living tissues. Micron-sized bubbles stabilized by a lipid shell were introduced into a limen of 10 microns in diameter created in acrylamide gel, and their dynamics under the conditions of exposure to 1-MHz short-pulsed ultrasound was observed using a high-speed video camera (HPV-X2, Shimadzu, Japan) equipped in a microscope (ECLIPSE Ti, Nikon, Japan) with an objective lens (Plan APO IR 40x, Nikon, Japan). The camera captured 256 frames at a framing rate up to 10 Mfps to visualize bubble dynamics inside a narrow capillary that will lead to ultrasound-enhanced extravasation. Oscillation of a water droplet of a few millimeters in size in air, which is the opposite situation of bubble oscillation in water, will also be discussed in this presentation.
Challenges in providing augmented hearing for individuals with hearing loss
Authors: Brungart Douglas S. , Best Virginia , Davidson Alyssa
Published: November 2023

Recently there has been an emphasis on developing augmented reality systems that can enhance the sensory signals listeners normally perceive in the real world. An early example of a practical augmented hearing system is the hearing aid, which amplifies the signals that would normally enter the ear in order to improve their audibility for hearing impaired listeners. Many applications are now envisioning the use of virtual audio technology to add synthetic, spatialized sounds to the “passthrough” audio signal that would normally be produced by a hearing aid. One challenge for the designers of both augmented and virtual audio systems is to ensure they preserve the ability of both normal and hearing-impaired listeners to determine the spatial locations of sounds in the environment. The auditory cues required for localizing sounds are well understood for normal hearing listeners, but less so for hearing impaired listeners. Here we discuss the results from two experiments where hearing-impaired listeners performed substantially worse than expected with virtual or augmented audio cues, and present preliminary results suggesting that the unexpectedly poor results from hearing-impaired listeners may be the result of a different weighting of localization cues across frequency regions than is typically observed for listeners with normal hearing.
What does it mean to sound Korean-Canadian, eh? A comparative study on Canadian English vowel space
Authors: Cho Sylvia
Published: November 2023

Existing research on Canadian English shows evidence of dialectal differences between regions. Not only are there differences based on region, but groups (e.g., heritage, immigrant) in these respective regions are not participating in the ongoing sound changes of Canadian English (e.g., Canadian Raising) to the same degree. In respect to sound changes, studies have found that some sounds are undergoing more drastic change than others, young female groups are usually more advanced in the progress, and that the largest heritage groups in major Canadian cities (Toronto, Vancouver, Montreal) are participating in sound changes—with some reported differences in vowel quality. This study extends the existing literature on Canadian sound changes by investigating the acoustic vowel quality of Korean heritage speakers in Vancouver. The speech of 11 monolingual Canadian English speakers and 22 Korean heritage speakers were analyzed for specific sound patterns (/u/-fronting, /æ/ raising) as well as overall vowel space area. This study finds that Korean heritage speakers also participate in the ongoing sound changes (e.g., /u/-fronting) but there are also some notable differences in their vowel acoustics, when compared to their monolingual counterparts.
Machine recognition of non-native speech: Task-specific language models versus large language models
Authors: Cheng Jian , Bernstein Jared C. , Suzuki Masanori
Published: November 2023

Automatic speech recognition (ASR) has offered a reliable foundation for measurement of young children’s reading skills and of second-language (L2) speaking skills. This is because well-fit task-specific language models (LMs) enable recognition that supports accurate scoring of pronunciation, fluency, vocabulary, usage, and grammar (Bernstein and Cheng, 2023). ASR works well in these measurement tasks because measurement of word production, disfluencies, and pronunciation errors is not very sensitive to moderate differences in word-error-rate (WER) accuracy, and because speech-interactive tasks appropriate for reading instruction or L2 assessment elicit relatively predictable responses, for which task-specific low-perplexity ASR systems achieve sufficiently accurate speech recognition (Cheng and Townshend, 2003). In the work reported here, we compared the accuracy of two English ASR systems on a set of 718 extended spontaneous speech recordings from 77 adult non-native speakers of English speaking from six countries under uncontrolled recording conditions. A Kaldi-based ASR system with well-fit task-specific LMs achieved WER 17%, while USM, a general-purpose mSLAM recognizer with an RNN-T decoder, achieved 11% WER, which is a 34% relative improvement. The mSLAM + RNN-T technology will be briefly described and an analysis of results in three different open-response interactive speaking tasks will be presented.