bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancing understanding of real-world listening experiences: Insights from ecological momentary assessments with assistive listening technologies
Authors: Mejia Jorge , Meng David , SEBASTIAN ARUN
Published: November 2023

Comprehending the daily listening experiences of people who use assistive listening technologies is difficult due to individual differences and the variety of listening environments they encounter. Consequently, a lack of comprehensive insight into real-world experiences often leads to misconstrued interpretations of research outcomes and future technological directions. Addressing this issue, the National Acoustic Laboratories (NAL) in Sydney, Australia, has been actively investigating the applications of ecological momentary assessments (EMA) since 2010. By employing EMA, NAL aims to comprehend the impact of assistive listening technologies in real-world conditions. To achieve this, we invested data from four distinct studies, encompassing more than 3000 survey entries. Utilizing an EMA app specifically developed by NAL, participants reported various challenges they faced in their listening experiences. These challenges include difficulties in understanding conversation when listening to a single speaker or in multitasking scenarios, as well as frustration with the loudness and annoyance of background noise. The analysis of this extensive dataset involved a combination of conventional statistical methods and advanced machine learning models. By employing these techniques, key insights were extracted from the data, offering valuable guidance for the design of future research conducted in real-world settings.
Robust improved multiband-structured subband adaptive filter for active noise control with impulsive interference
Authors: Pradhan Somanath , Zhang Guoqiang , Qiu Xiaojun , Ji J. C. , Parnell Jeffrey
Published: November 2023

The feedforward filtered-x least mean square algorithm is extensively implemented for active control of broadband noise. However, the control performance is substantially deteriorated due to colored noise and the presence of uncorrelated disturbances near the reference and error sensors. To tackle these issues, in this paper, a robust improved multiband-structured subband adaptive filter based on logarithmic and total least squares method is proposed for active control. Unlike the conventional method of total least squares, the proposed algorithm adopts logarithmic and Rayleigh quotient functions. The closed loop implementation of the improved multiband-structured subband adaptive filter is adopted to meet the delayless requirement. The proposed algorithm is well-suited for environments where the reference signal is highly correlated and the residual noise is contaminated by impulsive noise. Furthermore, an affine combination of the proposed algorithm is developed to meet the complementary requirements of faster convergence and improved noise reduction. Eventually, the stability and computational complexity are studied. Simulation results using measured acoustic paths in an anechoic chamber and a normal room illustrate the effectiveness of the proposed algorithm for controlling broadband noise with impulsive interference. In addition, the tracking control performance is evaluated in a time-varying acoustic environment.
Dynamic neural network switching for active noise control of nonlinear systems
Authors: Pike Xander , Cheer Jordan
Published: November 2023

Advancements in digital technologies have allowed for the development of increasingly complex active noise and vibration control solutions, with a wide range of applications. Such control systems are commonly designed using linear digital filters which cannot fully capture the dynamics of nonlinear systems. To overcome this, it has previously been shown that replacing linear controllers with neural networks (NNs) can improve control performance in the presence of nonlinearities in both the system plant and primary path. Inferring the outputs of NN controllers can, however, be computationally expensive, limiting the practicality and real-time performance of such control systems. It has been demonstrated previously that, with nonlinearity in the primary path, the range of nonlinearity over which a single NN controller can achieve significant levels of control is limited by the size of the NN. In this paper, a method of dynamically switching between multiple smaller NN controllers is presented. In a simple time-discrete simulation, the performance and computational cost of this approach is compared to that of individual fixed NN controllers, demonstrating improved computational efficiency and performance over a range of nonlinearity as the system disturbance changes over time.
A hat-shape error microphone array for user-friendly spatial active noise control
Authors: Sun Huiyuan , Jin Craig , Zhang Jihui (Aimee) , Samarasinghe Prasanga N. , Abhayapala Thushara
Published: November 2023

Spatial active noise control (ANC) has been developed in the past decades to reduce unwanted acoustic noise over a desired region by generating an anti-noise field with secondary loudspeakers. Unlike conventional multi-channel ANC systems, the integration of spherical harmonic-based sound field analysis allows the ANC system to reduce noise over a continuous region surrounding the user's head rather than discrete points. However, the use of a spherical error microphone array on the boundary of the region for spherical harmonic analysis poses a limitation as it obstructs user access to the controlled area. In this work, we introduce a hat-shaped error microphone array design which can be placed above the listener's head. The proposed error microphone array can achieve spherical harmonic-based residual noise field analysis and is more user-friendly, allowing unrestricted user head movement. We construct the hat-shaped error microphone array and present the results of ANC experiments conducted using the array.
Quantifying acoustic performance and embodied carbon of acoustic solutions for mass timber buildings: Comparing common approaches around the globe
Authors: Callaghan Aedan
Published: November 2023

As mass timber continues to increase in popularity as a building method to shifting away from high embodied carbon concrete structures to utilize wood as a renewable and lower embodied material. As whole building life cycle assessments (LCA) become more essential in meeting environmental emissions targets and qualifying for sustainability linked financing, quantifying the embodied carbon of both the structure and all other elements is necessary. The acoustic challenges of mass timber have been well documented and studied in previous works with a range of solutions now commonly utilized. Like most elements of construction, regionality results in different techniques being more popular and practical in different parts of the world. This work will compare the airborne and structure borne sound transmission and associated embodied carbon of four common acoustic designs for mass timber construction: floating concrete toppings, isolated board and batten floor systems, isolated dry floor linings, and raised access floors.
Round-robin tests of the different types of sensors for floor impact sounds and vibrations
Authors: LEE Jakin , Haan Chan-Hoon
Published: November 2023

Recently, floor impact noise monitoring system was introduced for residents to control making noises spontaneously using sound and vibration sensors. The present study aims to investigate the performance and characteristics of various current using sound and vibration sensors which can be eventually compatible with the floor impact noise monitoring system. For measurements of sound sensors, 7 sound microphones were used including 2 condenser types, 4 dynamic types, and 1 electro condenser type. Also, 6 vibration meters were used including 2 MEMS types, 2 Piezo types, and 2 spring types. Sound levels were measured in a semi-anechoic chamber using white noise in the frequency range from 63 Hz to 12.5 kHz. Vibrations were measured using high density wooden panel with an impact ball in the frequency range from 16 Hz to 4 KHz. Round-robin tests were done to confirm the exact performances of all the sensors under same condition. As a result, it was found that dynamic type microphones show the most similar response characterization in comparison with the reference condenser microphone especially in the air-borne sound frequency range from 250 Hz to 2 KHz. Also, it was found that spring type vibration meters show the most appropriate characterization at 63 Hz, most critical structure-borne sound frequency. Thus, the results drawn from the round-robin tests could be used for floor impact noise monitoring systems with the benefit of both economy and performance.
Further development and testing of a rainfall test rig
Authors: Latimer Michael D. , Yeoman Sebastian
Published: November 2023

Changes made recently by The Ministry of Health New Zealand, to the internal noise design requirements for Preschools, has required that the design of the roof reduces rainfall noise to Ministry of Education, Design Quality Learning Spaces Acoustics (DQLS) Version 3.0, for rainfall noise. Previously Canterbury Acoustic Testing Services (CATS) had developed a rainfall noise test rig, in accordance with ISO 10140-1: 2016 [3] and ISO 10140-5:2010/Amd 1:2014 and carried out testing on a series of warm roof/ceiling constructions. Preschools tend to use cold roof systems where the thermal insulation sits on the ceiling, rather than in a warm roof, where the insulation is part of the roof structure. So there has been no tested performance data for rainfall noise acoustic design purpose, using a cold roof construction. As part of the testing program, there was a need to recommission the rig, to verify rain drop size and rainfall rate. A testing program was established, to include the base roof structure (roofing iron only) to a full buildup of roof and ceiling, to get a better understanding of how each component in the system contributes to the control of the rainfall noise.
A review of sound radiated by breaking ocean waves
Authors: Deane Grant B.
Published: November 2023

“Physical Mechanisms of Noise Generation by Breaking Waves—A Laboratory Study” was published over 35 years ago by Mike Banner and Doug Cato. This seminal work describes a laboratory experiment demonstrating that the dominant source of breaking wave noise above a few hundred Hz is associated with the formation of bubbles and coalescing or splitting bubbles. This observation opened the door to explaining the properties of ambient sound under wind-driven seas and remotely monitoring air entrainment by breaking waves. Progress on these topics since Banner and Catos’ experiment will be reviewed and outstanding issues discussed. [Work supported by the US Office of Naval Research Ocean Acoustics program (Grant No. N00014-21-1-2316).]
Measurements of a 20, 440, and 3130 cubic inch air gun or array off Peregian Beach Queensland and Dongara Western Australia highlight small and large scale inhomogeneous sound propagation environments
Authors: McCauley Robert , Cato Douglas H. , Dunlop Rebecca , Noad Michael
Published: November 2023

During the project “Behavioural Response of Australian Humpback whales to Seismic Surveys” three air gun configurations were used to quantify the response of southerly migrating humpback whales to a northerly travelling air gun. Off Peregian Beach, Queensland (26.5o S latitude) a 20 cubic inch (cui) single air gun, 440 cui and 3130 cui arrays were operated while off Dongara, Western Australia (29.5o S) the 440 cui array was operated. At a first glance, we assumed within the respective ∼200 km2 experimental areas sound propagation was reasonably uniform but this was not the case. At Peregian Beach, flat supposedly sandy areas had patchy outcrops of soft “coffee” rock which dramatically increased sound propagation loss while in the north a large arc of hard reef or shallow sand over reef again increased sound propagation loss and acted as an “amphitheatre.” Off Dongara different depths of sand or no sand over a limestone base created variable sound propagation. When comparing Dongara and Peregian Beach the shallow limestone off Dongara increased propagation loss compared to Peregian. This talk will explore some of the idiosyncrasies of air gun propagation and inhomogeneities which can be expected when planning sound exposure experiments.
Forward looking sonar applications for unmanned vehicles
Authors: Romaine Peter D.
Published: November 2023

Unmanned vehicles have the potential to greatly expand our ability to observe dynamic ocean environments. Whereas distributed acoustic sensors can monitor discrete measurement points in time and space, autonomous maritime platforms provide increased flexibility. Acoustic principles are a key component of this functionality and forward looking sonar (FLS) systems can acquire acoustically derived data products while enabling better informed autonomy behaviors based on enhanced situational and environmental awareness. This paper explores applications of forward look sonar technology when integrated with underwater vehicles. Utility of both interferometric and two-dimensional acoustic data products are examined to illustrate the impact on technologies associated with navigational drift mitigation and ocean observation. Results from sonar platform integration and in-water acquisition for development of an underwater terrain-aided navigation (UTAN) particle filter, an acoustic enabled simultaneous localization and mapping (SLAM) algorithm, obstacle avoidance techniques, and seabed observations are presented.
Acoustic energy reflections from deep seabed layers in seismic reflection surveys
Authors: Douglass Alexander S. , Wood Warren T. , Phrampus Benjamin J. , Abadi Shima
Published: November 2023

Data from marine seismic reflection surveys are generally used to study the composition of the seabed 100s to 1000s of meters below the seafloor. These surveys consist of an airgun array that broadcasts an impulsive signal towards the seafloor, the reflections of which are measured by towed hydrophone streamers and used to invert for geophysical properties. The abundance of data from these surveys provides many opportunities to conduct acoustic analyses and to utilize data-driven approaches. Here, the extensive datasets are used for analyzing the impacts of seabed characteristics on the acoustic fields in the water column. Various seabed components are considered and their influence on the acoustic field quantified. It is shown that layers well below the seafloor can contribute up to 50% of the acoustic energy reflected into the water column at frequencies below 100 Hz and ranges approximately three times the channel depth. Additionally, non-intuitive relationships between layer depths and acoustic energy are explored. [Work supported by ONR.]
Assessing the feasibility of conducting coastal acoustic tomography using BELLHOP modeling
Authors: Kim Wan-Gu , Kim Byoung-Nam , Choi Bok Kyoung , Park Jungyong , Ji Ho Youn , Choi Min-Seok , Park Seng Hyeon
Published: November 2023

In order to apply coastal acoustic tomography (CAT) efficiently to a specific coastal area, it is necessary to design a measurement system in consideration of various variables related to the marine environment of the area. In particular, to consider seasonal variations in the water temperature structure quantitatively is important regarding the formation of sound rays. In this study, the feasibility of performing CAT according to the seasonal variations in the water temperature structure of Yeosu and Gwangyang Port was studied through simulation using BELLHOP model. First, BELLHOP model simulations were performed using the precise chart data and seasonal water temperature structure data of Yeosu and Gwangyang Port as input data. As a result, signal received during transmitting and receiving between candidate locations of stations could be calculated for each season. And, by estimating the minimum sound source level required to obtain an identifiable peak from the SNR value of the signal, the feasibility of tomography measurement could be assessed. It is expected that some important information, in constructing a tomography system with specifications appropriate for any coastal area of interest, can be provided in advance utilizing the method used in this study.
Biomechanical properties of the myopic choroid
Authors: Hoang Quan V. , Ito Kazuyo , Hoerig Cameron , Dan Yee Shan , McFadden Sally A. , Mamou Jonathan
Published: November 2023

Retina-derived growth signals relayed from the choroid to the sclera cause remodeling of the extracellular matrix, resulting in myopic ocular elongation. However, no studies have assessed changes in choroidal biomechanical properties during myopia progression. The present study utilized 7-μm-resolution scanning acoustic microscopy (SAM) to assess biomechanical properties of choroids in guinea pig eyes with form-deprivation (FD) induced myopia. Specifically, neonatal guinea pigs underwent unilateral FD for 1 week (resulting in moderate to high myopia). 12-μm-thick serial cryosections of eyes were scanned with SAM and two-dimensional maps of bulk modulus (K), mass density (rho) were calculated. We found that the choroid had considerable intrinsic strength arising from its biomechanical properties and these were differentially affected by myopia in central and peripheral regions. Choroidal biomechanical values were also highly correlated with those in adjacent scleral regions, and the choroidal-scleral association was stronger in myopic eyes. In conclusion, biomechanical changes observed in the choroid of myopic eyes were mirrored to those observed in the adjacent sclera. These new findings suggest that the choroid remodeling may accompany myopia and opens the door to the source of the signals that cause scleral remodeling in myopia.
Spectral-based quantitative ultrasound for assessing vision degrading myodesopsia
Authors: Hoerig Cameron , Nguyen Justin , Mamou Jonathan , Venuat Cedric , Sebag J. , Ketterling Jeffrey A.
Published: November 2023

The presence of clinically significant vitreous opacities, referred to as vision degrading myodesopsia (VDM), reduces contrast sensitivity (CS), and visual quality of life. Quantitative ultrasound (QUS) methods operating on grayscale B-mode images were previously developed and validated for quantifying vitreous echodensities. Although a subsequent study comparing the QUS methods across clinical scanners demonstrated no change in QUS efficacy, the methods are sensitive to differences in system parameters and B-mode image formation unless the backscatter data is normalized. Technological advancements in clinical scanners allow for easy access to raw radiofrequency (RF) data for more advanced processing methods. Here, we develop QUS methods that exploit RF echo data to generate robust user- and system-independent parameters for quantifying vitreous echodensities based on the echo signal power spectrum (PS). However, the sparsity of echodensities in the vitreous body is incompatible with underlying assumptions of QUS methods based on measurements of the backscatter coefficient or envelope statistics. We, therefore, implement QUS methods that parameterize the PS and correlate these parameters with visual function as measured by CS. Results from this study are the first step toward developing and validating robust, user-, and system-independent QUS methods for evaluating VDM.
Intraocular pressure measurement method using acoustic signals
Authors: Toh Gyungmin , Jeon Seongwook , Park Junhong , Lee Won June
Published: November 2023

Glaucoma can cause blindness, and one of the main causes has been found to be compression of the optic nerve by high intraocular pressure (IOP). In glaucoma, IOP is the most important biomarker for disease diagnosis, treatment, and monitoring. Among methods designed to measure IOP, direct contact with the eyeball is the most commonly used method due to its high accuracy. However, this method requires the intervention of a medical staff, and has problems, such as infection, fear, and corneal damage, which occur when the patient's IOP is measured. Therefore, in this study, while overcoming these problems, we intend to present a new IOP measurement method that inherits the advantages of the existing method. The eyeball has a structure in which body fluid is contained in an outer shell of viscoelastic material, and the change in pressure applied to the outer skin according to the inflow of body fluid appears as IOP. When an acoustic signal is emitted to an eyeball with a different IOP, the wave propagation characteristics vary depending on the composition of the body fluid, and the IOP is estimated. It is expected that the patient can directly measure and manage IOP using the proposed method.
Quantification of liver fat using ultrasound technology
Authors: Allen Heather , Edwards Christopher
Published: November 2023

Non-alcoholic fatty liver disease (NAFLD) is a growing concern worldwide, creating significant clinical and economic burdens. NAFLD has the potential to progress to advanced liver disease, which is associated with significant morbidity and related mortality. Research to address these challenges is ongoing and requires the use of reliable liver fat quantification tools to evaluate effectiveness. Magnetic resonance imaging has been established as a reference standard to replace liver biopsy (the traditional gold standard); however, cost and access limit its use in large patient groups. Recent advances in ultrasound-based liver fat quantification technology are promising, offering a more accessible, cost-effective method for estimating the quantity of liver fat. In this presentation, the authors outline how ultrasound attenuation and backscatter coefficients can be used to estimate liver fat percentage, discussing how this new tool has the potential to greatly impact the assessment and management of fatty liver disease.
Demonstration of medical imaging using flexible polymer ultrasound technology
Authors: Fillinger Laurent , Hörchens Lars , Peters Laurens C.J. M. , Verbeek Roy G.F. A. , Peeters Bart , Schrama Thijs , Merks-Swolfs Egon J. W. , van der Steen Jan-Laurens , Volker Arno W. F. , Gelinck Gerwin H. , van Neer Paul L.M. J.
Published: November 2023

We present a novel ultrasound transducer technology based on piezo polymers. Its fabrication process (PillarWaveTM), based on creating hexagonal micro-structured PVDF-TrFE pillars. This makes it fully flexible and allows scaling to large apertures (>15 × 15 cm2). Large area flexible transducers enable to select relevant field of view in automated post-processing. This can alleviate the need for a skilled sonographer and enable applications of echography outside clinics. To demonstrate its performance, a 128 element 8 MHz linear array is designed and manufactured. Its total thickness is 0.1 mm. Its acoustic characteristics are determined demonstrating 5.2 kPa/V transmit efficiency and 150 mV/Pa sensitivity. The receive bandwidth at -6dB is larger than 100%. A peak pressure in excess of 1 MPa at 4 cm from the array is measured in water. The transducer array is connected to a Verasonics Vantage research medical ultrasound system. The imaging performance of the array is demonstrated experimentally. Real-time imaging of an in vitro- medical phantom using plane wave compounding and delay-and-sum beamforming is demonstrated at 15 frames per second, with point spread functions at -20 dB of 1.3 and 0.92 mm in the lateral and depth directions, respectively. Finally, imaging of a human carotid in vivo is demonstrated.
Enhancing heart disease diagnosis through precise heart sound including infrasound
Authors: Kim Youngsin , Moon Mihyung , Moon Seokwhan , Moon Wonkyu
Published: November 2023

Recent research has been pushing the frontier of diagnosing cardiovascular diseases, which have a high mortality rate globally. The need for swift responses to acute diseases has underscored the importance of continuous health monitoring and the development of monitoring diagnostic technology. Our work focused on an overlooked aspect—the microphones used to measure heart sounds. Existing ones, particularly capacitive MEMS types, measure only heart sounds primarily within the audible frequency range, potentially limiting the diagnostic accuracy. To overcome these limitations, we used microphones capable of measuring down to infrasound areas. We also designed an experimental environment to capture the precise heart sounds. The crux of our approach was using the full information of heart sounds through infrasound measurements. A convolutional neural network-based deep learning model was employed for algorithm development and validated using the PhysioNet 2016 CinC’s open-source heart sound data. We conducted an experiment on the impact of low-frequency components on heart sound diagnosis using a new infrasound dataset measured at Seoul St. Mary's Hospital of the Catholic University of Korea. Accuracy and sensitivity, respectively, improved on average by 2% and 4%, showing that datasets including low-frequency components generally performed better.
Exercising prediction validation methods for analysis of quiet supersonic overflight
Authors: Loubeau Alexandra , Ballard Kathryn , Doebler William , Cruze Nathan B.
Published: November 2023

En route noise certification procedures for quiet supersonic aircraft are in development under the International Civil Aviation Organization for a proposed standard that could enable civil supersonic overland flight. While these quiet supersonic aircraft do not exist yet, methods are being developed and evaluated using existing N-wave empirical datasets and low-boom simulation datasets. One potential aspect of future certification methods is the ability to use a validated prediction model to predict the certification noise level under reference day weather conditions. Methods to validate predictions, such as the two-sample t-test, Fisher's combined probability test, two-sample Kolmogorov–Smirnov test, and equivalence testing, have been exercised and modified for this application. While some methods compare mean values, others compare values across the distribution, and a combination of methods can be used. The methods were applied to a subset of an N-wave dataset to demonstrate the applicability and identify potential areas for improvement. Atmospheric turbulence variability was included as a factor in these analyses through KZKFourier propagation simulations with parameters matching actual flights and weather conditions. Results are presented for six noise metrics (PL, ASEL, BSEL, DSEL, ESEL, and ISBAP), and plans to expand the analyses are discussed.
Air show primary sonic booms across a seismic network
Authors: Rathnayaka Sampath , Nyblade Andrew A. , Sparrow Victor W. , Riegel Kimberly
Published: November 2023

Cates and Sturtevant (2002) and others have shown that sonic booms can be recorded using existing seismic networks. To revive this capability for current research, data from permanent seismic stations were utilized to extract primary sonic boom signals from known supersonic flights. The sonic booms were produced on October 14, 2022 near Edward Air Force Base, CA, associated with an Air Show corresponding to the 75th anniversary of the first supersonic flight. The sonic booms were created by F-22, F-18, and F-15 aircraft. The experimental results show that primary sonic booms were measured at different times by seismic networks in Southern California over an area of not less than 10 000 km2 (∼3900 mi2). Secondary booms did not occur during this event due to inadequate upper atmospheric winds. [Work supported by the FAA through ASCENT Project 57 under the supervision of Sandy Liu. Any opinions, findings, conclusions, or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the FAA.]
Application of turbulence filters on PCBoom predictions for two NASA flight test campaigns
Authors: Nyborg Kaylee , Durrant J. T. , Gee Kent L. , Doebler William , Loubeau Alexandra
Published: November 2023

In preparation for the NASA X-59 community noise tests, the effects of turbulence on predictions of sonic boom levels are studied. This work builds on previous studies by including the effects of turbulence via finite impulse response filters implemented in the PCBoom prediction program. The resulting turbulized sonic boom predictions are compared to measured boom metric levels from previous NASA flight tests: Quiet Supersonic Flights 2018 and Carpet Determination in Entirety Measurements Phase I. To determine the factors driving differences between predictions and measured levels, least absolute shrinkage and selection operator (Lasso) regression is used to create a reduced-order model for each flight test campaign. [Work supported by NASA Langley Research Center through Analytical Mechanics Associates.]
Challenges in measuring and quantifying sonic booms from Falcon-9 booster landings
Authors: Durrant J. T. , Nyborg Kaylee , Anderson Mark C. , Gee Kent L. , Hart Grant W. , Hall Lucas K.
Published: November 2023

Sonic booms from Falcon-9 booster landings contribute to the overall noise of the vehicle, but obtaining high-fidelity acoustical measurements and robust metric calculations of each sonic boom pose several challenges. This paper discusses three such challenges: sonic boom metric variability from differences in vehicle trajectory and meteorology, poor low-frequency response of low-sensitivity microphones, and contamination of the sonic boom by the landing burn noise. To quantify the variability between measurements, boom metrics are compared across four separate launches from Vandenberg Space Force Base. Boom metrics calculated from microphone stations at the same location differ by as much as 10 dB from launch to launch. Next, a digital pole-shift filter helps correct the low-frequency response of low-sensitivity microphones near the pad. These filters are adjusted so the waveforms more closely match those from microphones with a superior low-frequency response. Last, to obtain a clean sonic boom waveform, tracking the noise source location and peak frequency may help to distinguish where the sonic boom ends and landing burn noise starts. However, due to similar frequency content and close spacing in time, separating the boom from the landing burn noise near the pad remains a challenge for some booms. [Work supported by USACE.]
Integrating ultrasound transducers in polymer additive manufacturing technologies to fabricate engineered composite materials with tailored properties
Authors: Raeymaekers Bart
Published: November 2023

Engineered composite materials that comprise filler material embedded in a polymer matrix may exhibit exotic physical properties that derive from the specific type, geometry, organization, and orientation of the particles in the matrix. However, existing techniques to manufacture such engineered materials are limited to laboratory scale, specific materials, and/or 2-D implementations, because it is challenging to organize and orient large quantities of particles into specific patterns. We utilize the acoustic radiation force associated with a standing ultrasound wave field to organize and orient particles of any material type dispersed in a fluid medium, into a user-specified pattern. We integrate the ultrasound wave field with several polymer additive manufacturing technologies to manufacture engineered materials in a layer-by-layer fashion, where in each layer we organize a user-specified pattern of filler using the acoustic radiation force. We demonstrate and discuss the integration of ultrasound transducers with several AM technologies and highlight their operating envelope and limitations. This research finds application in 3-D printing engineered materials with tailored properties by tuning the geometry, surface area, local packing density and, thus, the properties of the material.
Beyond-nearest-neighbour metamaterials
Authors: Chaplain Gregory J. , Moore Dan , Hooper Ian , Hibbins Alastair , Sambles John , Starkey Timothy
Published: November 2023

Engineering the dispersion of acoustic or elastic waves using coupling terms that spatially reach beyond the immediate local environment, or unit cell, is an “emerging topic” in Metamaterial design. In this talk, we present experimental studies in acoustic and elastic systems that realize beyond-nearest-neighbour coupling to introduce dispersion relations with extrema within the first Brilloun Zone. In acoustics, we use mixed waveguide-surfacewave coupling, while in elasticity we develop an elastic scaffold (made from meccano) with reconfigurable coupling elements and demonstrate the effects of structural symmetries on these exotic dispersion relations. Applications to enhanced energy harvesting structures are presented by leveraging zero-group-velocity modes.
Early prosodic marking of irony and its perception in autistic and neurotypical adults
Authors: Tatar Csilla , Brennan Jonathan , Krivokapić Jelena , Keshet Ezra
Published: November 2023

The present study examines the utterance-initial prosodic marking of irony and its perception in neurodiverse populations. We ask (i) whether speakers and listeners use prosody to mark irony in the early, “pre-target” portion of an utterance (before a “target” word most closely associated with ironic intent), (ii) whether individuals vary in how they mark irony, and (iii) whether listener accuracy varies by speaker or autism condition. Eight American English speakers were recorded producing utterances presented in contexts conducive to either irony or sincerity. The “pre-target” parts were presented in a forced-choice experiment to 55 autistic and 45 neurotypical listeners and were examined for syllable duration and F0-related properties (maximum, minimum, range, mean, and wiggliness [Wehrle, Cangemi, Krüger, & Grice. (2018) Proceedings of AISV]). Results show that speakers mark irony in the “pre-target” region, with duration being the most salient feature, and wiggliness and F0-range being variable. Most listeners recognize irony from “pre-target” fragments, but there is variation in how well each speaker is perceived. Whether the listener is autistic or neurotypical does not predict accuracy. Results, thus, show utterance-initial prosodic marking to contribute to irony recognition, with the proviso that speaker and listener variation be taken into account.
Acoustic analysis of video conferencing platforms: Evaluating communication effectiveness for individuals with hearing loss
Authors: Sebastian Arun , Zhang Vicky , Kitterick Pádraig
Published: November 2023

AIM: This research investigates the impact of video conferencing platforms on the transmitted sound to evaluate their effectiveness in facilitating communication for individuals with hearing loss. The preliminary analysis includes comparing the transmitted sound deviations from source recordings in Teams, Zoom, and Google Meet and exploring differences in audio quality across different settings within each platform (not focused on DSP limitations or audio transmission fidelity). METHODS: In this study, we employed babble noise, BKB speech, and a combination of babble noise and BKB speech (SNR: 9dB) as stimuli. We compared different acoustic features of the received signal, including automatic audio gain adjustments, frequency range, and frequency response, with the source sound. RESULTS: Zoom applies a smooth high-frequency roll-off for speech in a noisy signal, beginning at approximately 14.5 kHz and removing all frequency content above 18 kHz. The roll-off for Teams begins at a relatively low frequency around 7 kHz. Although Google Meet starts the roll-off around 20 kHz, the gain was inconsistent and had a sharp roll-off. CONCLUSION: Each platform exhibited distinct characteristics and introduced noticeable modifications to the stimuli. Results indicated that Zoom with optional audio settings enabled demonstrates the highest fidelity to dynamic range and frequency spectrum.
A preliminary investigation of the acoustic factors impacting decision making in speaker attribution
Authors: Loakes Debbie , Fraser Helen , McDougall Kirsty
Published: November 2023

Attributing utterances to speakers in a good quality recording of clear speech might seem to be a simple and straightforward task, yet transcribers have been shown to “regularly and obliviously get it wrong” (Love 2020: 156). This issue has received very limited attention, and our research focuses on the issue from a forensic linguistic perspective where attributing an utterance to a speaker in a forensic case could effectively be accusing them of having committed a crime. Literature on speaker attribution/recognitionnever shows 100% accuracy even in very good acoustic conditions, with marked drops in performance when features are masked (as they often are in forensic situations). In this preliminary study, five phonetically trained listeners transcribed an audio file of six people engaged ina panel discussion from television (we focus on audio only). The speech of two female speakers is correctly attributed in almost all cases, so we pay attention to the acoustic features of four male voices. Listeners werealmost never correct in their judgements about the exact number of speakers in the recording and made multiple attribution errors. We show that this is because of the fundamental nature of the speech acoustics; within-speaker variation is larger than between speaker variation for F0, intonational properties, and speech rhythm. Love, R. (2020). Overcoming challenges in corpus construction: The spoken British National Corpus 2020. Routledge Advances in Corpus Linguistics. New York: Routledge.
Is vowel devoicing in Japanese lexically specified?—An eye-tracking study
Authors: Kitahara Mafuyu , Shirose Ayako S. , Yoshida Natsuya
Published: November 2023

In Tokyo Japanese, high vowels can be devoiced typically between voiceless consonants. Traditionally, devoiced vowels are treated as allophones of corresponding vowels in which the devoicing process is a result of phonetic implementation commonly affected by speech rate. An opposing view is that devoicing is lexically specified since there are cases of interactions between devoicing and compounding that can be naturally accounted for by lexical phonology. To investigate this issue, the present study conducted an eye-tracking experiment. Edited mismatch stimuli where vowels were voiced before a voiceless consonant (M1) or devoiced before a voiced consonant (M2) were auditorily presented with pictures of the target word, a competing word, and a distractor presented visually. This design is based on a prediction that M1 and M2 invoke confusion in the recognition process if devoicing is specified lexically. Sixteen participants were recruited for an experiment of about 200 trials. Results showed that only M1 stimuli invoked a different pattern of fixation rates than M2 and other natural stimuli. This can be interpreted as partial support for the traditional view of devoicing. The asymmetry between M1 and M2 calls for an account based on markedness theory which is independent of the lexical specification.
Analysis of binaural sound pressure control and virtual source characteristics in stereophonic reproduction
Authors: Ding wenjie , Xie Bosun
Published: November 2023

In stereophonic reproduction, the manipulation of relative magnitude and phase between two loudspeakers enables to create virtual sources within an azimuth region in frontal–horizontal plane. The law of sine, which is based on evaluating the interaural phase difference and a conventional method for stereophonic analysis at low frequencies, fails to explain some characteristic in stereophonic reproduction, including the influence of span angle of loudspeakers on virtual source localization and the stability of virtual source created by out-of-phase loudspeaker signals. Analogy to the method in active sound control, an alternative method for analyzing the characteristics of virtual source in stereophonic reproduction is presented in this work. On the basis of shadowless head model at low frequency, the power effort of loudspeaker signals for creating virtual source in stereophonic reproduction is evaluated. The results indicate that for frontal virtual source within the span of loudspeakers, the power effort of in-phase loudspeaker signals increases with the increase in the span angle of loudspeakers. For lateral virtual source outside the span of loudspeakers, the power effort of out-of-phase loudspeaker signals increases with the target azimuth of virtual source. Increase in power effort makes the control of binaural pressures difficulty and, thus, virtual source instable.
Sound pressure and particle motion calculations considering pile skin friction
Authors: Koessler Matthew W. , Hannay David E. , MacGillivray Alex
Published: November 2023

Modelling sound propagation over seabeds where the seabed cannot be approximated as an equivalent fluid due to limestone layers with high shear wave speeds is a common underwater acoustic propagation modelling problem for Australian shallow marine environments. With the increase in prospective areas for offshore windfarm development across Australia, construction operations across large regions of the continental shelf area are set to increase. Windfarm construction will require the installation of a large number of foundation piles near potentially sensitive marine habitat areas. Predicting the underwater noise from these activities requires suitable models. This paper investigates the modelling approaches for including a full elastic parameterisation of the seabed when conducting numerical predictions of pile driving sound emissions. The approach considers buried sources and the excitation of shear waves via a skin friction model for the stress–strain relation at the pile-seabed boundary. Shear waves are considered in the source model and in the propagation model. Sound pressure level metrics and particle motion metrics are considered as part of the numerical predictions.
Estimation of sediment compressional and shear properties in the New England Mud Patch using acoustic pressure and particle velocity data
Authors: Potty Gopu R. , Miller James H.
Published: November 2023

New England Mud Patch was the site of the Seabed Characterization Experiment in multiple years (2017, 2021, and 2022). This site is characterized by a layer of very fine grained surficial sediment layer over sand. Analysis of broadband data measured on the ocean bottom recorders (OBXs) and hydrophones will be discussed. OBX is a geophone–hydrophone system which measures three components (two orthogonal horizontal components and a vertical component) in addition to acoustic pressure. Five OBXs were deployed on the seabed and four hydrophones were configured as a tetrahedral array on the bottom mounted Geosled. Data from these sensors will be analyzed and different arrivals corresponding to compressional, shear and interface wave (Scholte and love waves) presence will be examined. Inversion schemes will be implemented to estimate the compressional and shear wave speeds and attenuation. A priori information from seismic surveys and sediment cores will be incorporated into the inversion schemes. Outputs of these inversions will be compared with inversion results from other investigators based on different inversion techniques and using data from the same location. [Work Supported by Office of Naval Research.]
Vector acoustic observations of ship noise and influence of sediment compressional speed gradients and shear rigidity in modeling
Authors: Dahl Peter H. , Dall'Osto David R.
Published: November 2023

For acoustic measurements made within the water column, it is well understood that observability of the effects of seabed shear rigidity varies widely depending, e.g., on source type, frequency range and measurement geometry. Measurements of underwater noise from a passing ship made with a vector sensor are discussed in this context. Data are expressed in a bounded, non-dimensional form known as circularity that provides a signal independent of the ship noise-source spectrum. The system was deployed 1.45 m above the seabed in waters of depth 77 m on the New England Mud Patch as part of the May 2022 Sediment Characterization Experiment. Broadband noise measurements (15i–500 Hz) of the ship are made during which the ship range varies from 10 to 1.5 km at closest point of approach. Observations are compared to an interpretative model based on the normal modes and a geoacoustic model consistent with studies conducted at this location; the defining characteristic being a low-speed mud layer constituting the upper ∼10 m of the seabed that transitions with increasing sand content. Emphasis in this presentation is on parameterization of the deeper seabed structure involving compressional sound speed gradients and sediment shear rigidity.
In situ measurements of sediment shear wave speed from the New England Mud Patch and shelf break areas using the acoustic coring system
Authors: Garcia Dante D. , Wilson Preston S. , Ballard Megan S. , Lee Kevin M. , Chaytor Jason D.
Published: November 2023

The acoustic coring system (ACS) is a probe-equipped gravity corer that provides in situ measurements of compressional and shear wave speed and attenuation. During an April 2022 coring survey, the ACS was deployed at 36 locations within the New England Mud Patch and New England Shelf Break areas. Data from these measurements will be presented to characterize the depth-dependent structure of the geoacoustic seabed properties as well as their spatial variability. The in situ measurements will be interpreted in the context of stratigraphic layering measured by a seismic survey. Historically, in situ shear speed measurements of the seabed have proved difficult to obtain. From the 2022 survey, depth-dependent (up to 4 meters) shear speed profiles at 800 and 1200 Hz were produced from a subset of the 36 deployments. These results, along with methods for analysis, challenges in the measurements, and supplemental laboratory experiments will be discussed. The results will also be compared to measurements from previous experiments. [Work sponsored by ONR.]
Cautionary tales at the intersection of audio and acoustics
Authors: Conant David A. , Hoover K. Anthony
Published: November 2023

Sound as perceived by audiences is necessarily influenced by both the direct-arrival audio and the acoustical conditions in the space. Influences of audio and architecture upon each other can sometimes confound intended results. This presentation draws upon examples from performing arts, education, and worship spaces for interesting examples that underscore the importance of steadfast diligence at the intersection of audio and acoustics.
Integrating spatial audio and active acoustics systems
Authors: Ellison Steve , Schwenke Roger
Published: November 2023

Rooms incorporating Spatial Audio and Active Acoustic systems are being built that facilitate immersive audience experiences of unprecedented musical performances. Composers are writing new pieces, and new versions of existing works are being produced to take advantage of these technologies. Spatial Audio enables pre-recorded, synthesized, and live reinforced sounds to arrive at the listener from any direction and allows the listener to move around in the space and explore the sonic experience. Active Acoustics provides early reflections and reverberance for the performers and audience throughout the room and can be adjusted for each composition. The physical acoustical design of the space needs to provide an appropriate nominal acoustic for both systems and accommodate performance audio that does not come from a fixed position and orientation to listeners who may not be in a fixed location and orientation. Both systems incorporate distributed loudspeakers that are typically integrated into the architecture yet have different electroacoustic objectives. How do these systems coexist? Installation examples that use Spacemap, a multichannel panner that originated in Australia, and Constellation, an Active Acoustics System that uses VRAS technology developed in New Zealand, illustrate design considerations when integrating these systems.