bluuebunny/crossref_metadata_2025 huggingface dataset:
VSpace: A browser-based vowel synthesiser
Authors: Proctor Michael I.
Published: November 2023

Two-formant representation of the universal vowel space is a foundational model in phonetics (Fant & Risberg 1963; Traunmüller & Lacerda 1983), but tools for rapid synthesis of vowel sounds corresponding to points in the vowel space are limited. Stand-alone applications such as the Formant Synthesizer Demo (Beskow, 2000) provide this functionality, and rich tools for formant synthesis are available in Praat (Boersma and Weenink, 2023), Matlab (Rabiner et al., 2023) and other platforms, but these tools are not universally accessible, while web-based speech synthesis tools (e.g., Thapen, 2017) do not typically allow systematic manipulation or quantification of key acoustic parameters. VSpace is a browser-based formant synthesizer developed using the Tone.js Web Audio framework. A universal vowel space is represented as a trapezoid scaled to typical male, female or child speaker formant ranges. Clicking on any point generates a vowel sound corresponding to the first and second formant frequencies selected, synthesized with typical F3 and F4 frequencies excited by a selectable source signal. IPA symbols corresponding to typical formant frequencies for language-specific vowel phonemes may be superimposed on the vowel space. Key synthesis parameters are configurable through the web interface to allow exploration of the acoustic consequences for vowel perception.
Prelateral vowel change in Australian English pool-pull trajectories
Authors: Szalay Tuende , Benders Titia , Cox Felicity , Proctor Michael I.
Published: November 2023

Australian English (AusE) pre-/l/ /ʉ:/ is retracted when coarticulated with coda /l/, leading to vowel change through acoustic contrast reduction between /ʉ:-ʊ/ (pool-pull). Younger speakers show smaller contrast in /ʉ:l- ʊl/ targets than older speakers. As vowel trajectories are less well understood, we tested changes in the F2 trajectory. 200 tokens of /ʉ:, ʊ/ in the /hVd, pVl/ contexts (who’d-hood, pool-pull), produced by eight younger (ages = 20–29) and nine older (ages = 54–80) female AusE speakers, were extracted from the audio corpus AusTalk. Formant trajectories in pre-/d/ vowels and /Vl/ rimes were extracted automatically, corrected manually, and time-normalized (0–1). F2 trajectory was fitted with a Generalized Additive Mixed Model using fixed factors Vowel, Coda, and Age (treatment-coded, comparing /ʉ:/ to /ʊ/, /l/ to /d/, younger to older) with Speaker as random intercept with smooths for Vowel and Coda. Both age groups maintained significant vowel contrast in the pre-/d/ context in the entire vowel trajectory. In the /l/-context, older speakers showed a significant F2 difference throughout the rime trajectory, while younger speakers did not. Durational differences may be maintained, as duration contrast was not analysed due to time normalization. Our findings are consistent with an AusE pool-pull merger.
Two efforts towards natural speech synthesis: Incorporating disfluency and speaking style change based on the interlocutor
Authors: Mokhtari Akiko , Campbell Nick , Sadanobu Toshiyuki
Published: November 2023

During the period 2000–2005, a Japanese female speaker recorded her everyday conversations with many different interlocutors using a head-set microphone. As a result, 600 hours of natural Japanese speech data were obtained. This study describes a DNN-based speech synthesis system which was trained on 300 hours of the data, focusing on two unique efforts to make it more expressive in a human-like way: (1) allowing for disfluencies, and (2) accounting for the category of interlocutor. Incorporating some frequently observed disfluent patterns in general Japanese speech such as fillers, phrase-final rising intonation, and word-internal prolongation or suspension, is believed to be effective in practical application as certain disfluencies are connected to a speaker’s attitude in Japanese communication. For example, having word-internal prolongations can show hesitation or politeness, and word-internal suspending can show the speaker’s surprised attitude. Interlocutors in the original data were categorized into four groups: family, friend, child and others. This information was used in the training process, and as a result, the synthesizer can generate different speaking styles according to the interlocutor setting. Being able to generate disfluent speech and change the speaking style depending on who you are talking to can make the synthesizer ever more expressive.
Location and size of constriction in labiovelar, velar, and uvular sounds in French
Authors: Islam Md Jahurul , Gick Bryan
Published: November 2023

This study investigates the location and size of constriction in the labio-velar sound [w]. While there have been studies exploring constrictions in different sounds including schwa [Gick, 2002, Phonetica 59], /r/ [Epsy-Wilsonet al., 2000, JASA 108], and clicks [Miller et al., 2009, JIPA 39], the understanding of the constriction in labio-velar sound [w] in relation to neighboring sounds is limited. We utilized an MRI corpus of French speech [Isaieva et al., Scientific Data 8] to measure the location and size of the constrictions in [w], [k], [u], and [ʁ]. The MRI video frames were manually traced to mark the upper surface of the tongue and the lower surface of the hard-palate, velum, and uvula, resulting in two contours. Using Euclidean distance, the location and size of the constriction were identified as the narrowest point and distance, respectively, between the two contours. Results confirmed that [w,u] had constrictions against the velum; [k]’s, however, had constrictions fronter than [w,u] (centroids were 0.88au apart on normalized X-Y space), making them more palatal. [ʁ]’s had uvular constrictions, as expected. Regarding constriction size, [w], despite being an approximant consonant, had a more open constriction than the vowel [u].
Lightweight modular construction of school classrooms, reverberation time prediction versus field testing
Authors: Parry-Jones Joel
Published: November 2023

Lightweight modular schools are in the early phases of being designed and constructed throughout NSW as part of Schools Infrastructure “Modern Methods of Construction (MMC).” This method proposes the use of CLT (Cross Laminated Timber) panels, timber floor and wall cassettes, and/or hybrid systems. Schools Infrastructure NSW has developed, along with PKA Acoustic Consulting’s acoustic input, the “Kit of Parts” catalogue which utilises predetermined set of components that can easily be assembled and constructed. The classroom layout is therefore defined and can be incorporated into the acoustic predictive model. Additionally, the absorption characteristics of lightweight constructions differ to conventional construction and therefore should be considered. This presentation discusses the significance of construction type and fitout finishes, by comparing predicted reverb times of modular lightweight classrooms with in-situ absorptive testing at various cold shell, warm shell, and completed fitout stages of a school classroom and open learning space.
Refurbishment of a vacated office building to provide high-performance music teaching and performance facilities in regional NSW
Authors: Reverter Garcia Jorge , Milton Joseph
Published: November 2023

In 2016, a Conservatorium of Music made a significant decision to move their music teaching and performance facilities, to a nearby vacated building situated 3km away. From the outset, the move presented the design team to deliver a state-of-the-art Conservatorium of Music, with several challenges due to the spatial and building constraints. Among the most notable of these challenges was the limited volume within the existing building which is an essential requirement for optimal music performance spaces. This paper outlines the users' expectations—which were gathered through an acoustic questionnaire, design process, details the specific challenges faced by the design team, and presents the design solutions devised to overcome these problems. The Conservatorium of Music opened in early 2023 and has been well received by users and audiences.
Classroom acoustics: A case study of the cost-benefit of retrofitted interventions
Authors: van Reenen Coralie
Published: November 2023

It is known that suitable classroom acoustics is important for effective teaching and learning. To this end, many countries have developed classroom acoustics standards. However, research shows that these standards are often not implemented. Research assessing the implementation of classroom acoustic standards internationally concludes that successful implementation is driven by mandatory standards that are part of the building codes and that the cost of compliance is a barrier. The study presented here explores the cost of upgrading classrooms to achieve a suitable reverberation time. The paper presents a case study in South Africa, where acoustic standards are generally not implemented and cost and know-how are barriers. The objective was to optimize the cost, acoustic benefit, and accessibility of acoustic interventions. Four adjacent similar classrooms were retrofitted with different sound-absorbing ceiling panels that cover a percentage of the ceiling area. The weighted sum model was used to assess the suitability of each intervention, taking into account the cost, acoustic benefit (in terms of reverberation time), and ease of access to materials. The case study demonstrates that a noticeable improvement in acoustic conditions can be achieved without significant cost and provides a basis for further research to develop simple standardized design recommendations.
Passive acoustic monitoring of artificial reefs south of Long Island, New York provides novel insights on fish, marine mammal, and post-pandemic human activity occurring in nearshore coastal habitats
Authors: Leone Melissa , Warren Joseph D.
Published: November 2023

Passive acoustic recorders were deployed at two artificial reef sites (25m water depth) south of Long Island, New York from 2020 to present. The study sites are popular recreational fishing locations but also near commercial fishing activities and shipping lanes for the Port of New York and New Jersey providing numerous types of human-generated signals which can be monitored. We investigated how human activities changed the nearshore soundscape following the global pandemic and found that periods (2020) following the pandemic shutdown were (in some regards) louder instead of quieter than soundscapes later on (2021). Peaks in power spectral densities recorded at the reef sites often corresponded to signals from idling or transitory vessels. In addition to human-produced sounds, signals from both fish and marine mammals are regularly heard on the reefs which provided the opportunity to investigate several ecological questions including: reproductive activity of commercially important cod and weakfish; residency of bottlenose dolphins through individual signature whistle analysis; and baleen whale usage of the nearshore habitat.
Application of lung ultrasound surface wave elastography in the evaluation of diffuse lung diseases
Authors: Kalra Sanjay , Bartholmai Brian , Zhang Xiaoming
Published: November 2023

The evaluation of diffuse lung disease invariably involves chest computerized tomography (CT). The detailed information obtained is often equivalent to that from lung biopsies. It, however, involves exposure to ionising radiation which limits its repeated application in monitoring and follow up. Ultrasound techniques offer potentially safer/cheaper alternatives and lung ultrasound surface wave elastography (LUSWE) is a novel, noninvasive, and clinically feasible technique to quantify lung stiffness, an important biomechanical property that changes in diffuse fibrotic and infiltrative lung diseases. We have developed a sensitive, accurate and reproducible technique to measure changes in lung surface stiffness by using surface wave transmission speed and demonstrated its value in detecting and staging the degree of fibrosis in diffuse interstitial lung diseases, specifically idiopathic pulmonary fibrosis and progressive systemic sclerosis associated lung disease, as well as changes in heart failure. The technique consists of ultrasound detection of the propagation speed of a wave generated by the vibrations from an indenting shaker in multiple intercostal spaces to provide a representative assessment of both lungs. It offers the prospect of simple, radiation-free, repetitive assessment of changes in acute and chronic diffuse lung diseases with the potential for easy and rapid bedside use, all important considerations in clinical practice.
Focused ultrasound-mediated delivery of anti-programmed cell death-ligand 1 antibody to the brain of a porcine model
Authors: Fadera Siaka
Published: November 2023

Immune checkpoint inhibitor (ICI) therapy has revolutionized cancer treatment by leveraging the body's immune system to combat cancer cells. However, its effectiveness in brain cancer is hindered by the blood-brain barrier (BBB), impeding the delivery of ICIs to brain tumor cells. This study aimed to assess the safety and feasibility of using focused ultrasound combined with microbubbles-mediated BBB opening (FUS-BBBO) to facilitate trans-BBB delivery of an ICI, anti-programmed cell death-ligand 1 antibody (aPD-L1), to the brain of a large animal model. In a porcine model, FUS sonication of targeted brain regions was performed after intravenous microbubble injection, which was followed by intravenous administration of aPD-L1 labeled with a near-infrared fluorescent dye. The permeability of the BBB was evaluated using contrast-enhanced MRI, while fluorescence imaging and histological analysis were conducted on ex vivo pig brains. Results showed a significant 4.8-fold increase in MR contrast enhancement volume in FUS-targeted regions compared to non-targeted regions. FUS sonication enhanced aPD-L1 delivery by an average of 2.1-fold, according to fluorescence imaging. In vivo MRI and ex vivo staining found the procedure did not cause significant acute tissue damage. These findings demonstrate that FUS-BBBO offers a noninvasive, localized, and safe delivery approach for ICIs in a large animal model, showcasing its potential for clinical translation.
Physical-model-based reconstruction of three-dimensional sound field from multi-directional measurement by parallel phase-shift interferometry
Authors: Nozawa Haruka , Imanishi Mayuko , Oikawa Yasuhiro , Ishikawa Keji
Published: November 2023

The high-spatial-resolution nature of optical non-invasive measurement and the reconstruction of three-dimensional sound fields are important for evaluating acoustic transducers. The computed tomography (CT) method has been used to reconstruct sound fields from optical measurement results because of its contactless feature. However, since the CT method does not assume any physical property of sound, it may not be suitable for the reconstruction of sound fields. In contrast, a physical-model-based method is able to reconstruct sound fields more accurately by considering the physics of sound. In this study, we propose a scan-free and physical-model-based reconstruction of a three-dimensional sound field. A sound field is multi-directionally measured using parallel phase-shifting interferometry and a high-speed polarization camera by rotating an acoustic transducer. A physical-model-based method is applied to reconstruct the sound field from the recorded optical interferograms. We also discussed the effectiveness of the proposed method to evaluate acoustic transducers.
An improved lumped parameter model of the single free-flooded ring transducer using Helmholtz–Kirchhoff integral solution
Authors: Lee Junsu , Been Kyounghun , Moon Wonkyu
Published: November 2023

The Helmholtz-Kirchhoff integral (HKI) may be considered as the boundary element method (BEM) used to calculate the acoustic pressure at any position in the 3D-radiation problem from a vibrating surface. This method provides valuable insights into the radiation characteristics of vibrating structures, which may offer significant information and tools to underwater transducer design engineers during the early stages of development. It may save considerable computational costs in the design processes for the underwater transducer such as Hull Mount Sonar. This study illustrates usefulness of the HKI-based approach by developing a simple model of the Free Flooded Ring (FFR) transducer using a piezoelectric ring model and the HKI solution on the surface acoustic pressure of the ring through their physical conditions on their connected interfaces. The FFR transducer is widely utilized as a low-frequency acoustic source in underwater environments due to its broad operating frequency bandwidth and relatively small size. The developed approach aims to construct a precise model that considers the sound-structure interactions between the piezoelectric ring and the acoustic medium around it. To validate the accuracy of the proposed method, the acoustic pressure and electrical admittance are compared with those obtained through finite element method (FEM) simulations.
Tackling the strange wind noise on a commercial building—Case study
Authors: Law Harvey
Published: November 2023

A mysterious noise was reported in a commercial building. This commercial building consists of multiple levels of car parks with one single level of office space at the top. This top-level office area is home to Renault Australia, Mulgrave, Victoria. The office staff at the Renault reported a dreadful “howling” noise around the office. It sounded like a huge truck thundering past the office, especially on windy days. Specialist engineers, acoustic and wind engineers, were summoned to investigate the root cause of this noise. The initial investigation revealed that on windy days, the exterior aluminium Z Perlin profile cladding created air turbulences, which resulted in this unwanted noise. After conducting tests in the Monash University wind tunnel, various recommendations were suggested and trialled. For example, removing some purlins to reduce the air-flow turbulence, attaching fibre cement sheets to seal the purlins, vibration damping treatment of the Z purling cladding, and absorptive infill on the metal purlins. This case study presents the analysis of the noise, the results of the various tests and the successful practical resolution.
Echo threshold measurement based on headphone presentation
Authors: Cao Teng , Yu Guangzheng , Rao Dan
Published: November 2023

Echo threshold(ET), as the upper threshold of the precedence effect, refers to the critical delay value when the listener transitions from perceiving a single fused sound image to two clear and separated sound images in the presence of two relatively delayed sounds. This study investigates the ET measurement using two kinds of headphone-based virtual sound source presentation methods, i.e., interaural time difference (ITD) lateralization and virtual auditory synthesis (VAS). The “lead-lag” paradigm was adopted in the experiment and an adaptive up-down procedure was used to measure ETs of four stimuli, including noise burst, speech, music and pink noise. The results demonstrate that ET is related to the type of signal and the presentation method. Long-duration signals (i.e., speech, music and pink noise) have greater ETs than short-duration signal(noise burst), which is due to the fact that the temporal overlap between lead and lag sound of long-duration signal would suppress the identification of the lag. ETs of ITD-based presentation were significantly greater than that of VAS-based method for long-duration signal, which indicate that different spatial cues produced by different presentation methods would influence the ET of long-duration signal.
Perceptual anchoring to auditory textures in human listeners
Authors: Mehta Divya , Shulver Kurt , McAlpine David , Hernandez Perez Heivet
Published: November 2023

Learning is crucial for the development of species, enabling them to acquire behaviours, accumulate knowledge, and refine skills. An example of implicit and unsupervised learning is “perceptual anchoring,” where the brain creates an internal representation of the statistical properties of a stimulus that it encounters repeatedly. Behaviourally, both recognition and discrimination of the repeated stimulus i.e., the anchor, increases over time. Here, we modified a white noise anchoring paradigm (Agus et al., 2014) to incorporate synthetic auditory textures (McDermott et al., 2013). Four sound textures recordings were used in this study: wind blowing, crackling fire, insects, and bubbling water. Normal hearers identified if two synthetic auditory textures were identical. Participants encountered three blocks of 80 trials per synthetic texture: 20 Fixed-Repeated (two identical excerpts within and across trials), 20 Repeated (two identical excerpts within the trial but never heard again) and 40 Novel (two different excerpts presented within and across trials). Anchoring to the Fixed-Repeated stimuli was observed in all participants. Sensitivity to the Fixed-Repeated stimulus was always significantly higher than to the Repeated stimuli for all textures individually and when collapsed. Here, we demonstrated that synthetized auditory textures are suitable to assess perceptual anchoring in human listeners.
Explaining the deterioration of the relative timing accuracy for across-channel by a simple mathematical model
Authors: Okazaki Satoshi
Published: November 2023

The perceptual simultaneity range, within which two asynchronous pure tones are perceived to start simultaneously, and the gap detection threshold are known to be wide when the frequency separation of the tones is large. It is generally said that the accuracy of the relative timing for different frequency channels deteriorates. However, there is no clear explanation of why such deteriorations are necessary. This study aimed to show that a simple mathematical model leads to the deterioration of relative timing accuracy for two tones with different frequencies. As a result of the calculations, the model simulated the deterioration of the perceptual simultaneity range not only with the increase of the frequency separation but also with the decrease of the frequency region of two tones. The model also simulated the behavior of the gap detection threshold for two different frequencies (across-channel) with its asymmetric deterioration. Further, the model simulated the behavior of the gap detection threshold for two identical frequencies (within-channel). These results suggest that one simple mathematical model may explain the mechanisms underlying perceptual simultaneity, within-channel gap detection, and between-channel gap detection for two tones.
Efferent involvement in neural adaptation to acoustical stimuli: Insights from otoacoustic emissions
Authors: Bridges Amanda , Mikiel-Hunter Jason , McAlpine David , Boothalingam Sriram
Published: November 2023

Neural adaptation to sound level statistics has been demonstrated at various levels of the auditory pathway, including the auditory periphery. Adaptation is thought to improve the efficiency of encoding acoustic stimuli using limited neural resources without compromising accuracy. However, the precise mechanisms underlying the statistical learning of an acoustic environment are not fully understood. This includes the potential contribution to the stimulus-specific modulation of afferent auditory nerve activity by the medial olivocochlear reflex (MOCR), an efferent feedback loop linking the brainstem to the cochlear amplifier. We used otoacoustic emissions (OAEs) to investigate evidence of neural adaptation in the MOCR in response to broadband elicitors of fluctuating intensity whose mean levels were either predictable (alternating low [48 dB SPL] and high [66 dB SPL]) or unpredictable (randomly occurring low and high mean levels). Magnitudes and time-courses of the MOCR obtained in normal-hearing ears were compared for differences based on the presence or absence of an acoustically predictable context. Our findings will provide valuable insights into the role of the efferent auditory system in neural adaptation to acoustical stimuli at the auditory periphery.
Acoustic and articulatory modifications of Mandarin vowels in clear and Lombard speech
Authors: Chang Yung-hsiang Shawn
Published: November 2023

This study investigated the acoustic modifications of Mandarin vowels /a, i, u/ in clear speech and Lombard speech. Their underlying articulatory movements in the tongue and lips were also examined using ultrasound imaging and lip videos. Plain (i.e., conversational), clear and Lombard speech productions were elicited through a series of map tasks, where participants were prompted by pre-recorded videos to interact with the listener on the screen. Results showed that clear and Lombard speech in Mandarin resulted in longer syllable duration as well as greater vowel RMS intensity than plain speech. Spectrally, not all three vowels were modified to enhance their phonological features in response to clear or Lombard speech conditions. However, the differential F1/F2 modifications did result in an expanded vowel space. Some associations and mismatches between F1/F2 measurements and articulatory movements were observed. Particularly, greater mouth opening and lowering of tongue body in /a/ in clear and Lombard speech could account for the raising of F1. Few modifications in /i/ tongue position and lip configurations also corresponded to no significant F1/F2 change. The acoustic-articulatory relationship for /u/, in contrast, was less straightforward. These observations are discussed in relation to existing clear speech and Lombard speech literature.
Exploring velar function in speech: An integrated approach using nasometry and high-speed nasopharyngoscopy
Authors: Oren Liran , Fletcher Brittany , Le Huy , Maduwantha Yashish , Espy-Wilson Carol , Tiede Mark , Boyce Suzanne
Published: November 2023

It is well established that coupling between the oral and nasal cavities is controlled by velopharyngeal opening and closing movements and that coarticulatory patterns in these movements can affect both the intelligibility and the naturalness of speech. In addition, poor control can cause individuals to develop undesirable compensatory patterns. Most studies of these patterns have relied on indirect methods to assess both extent and timing of movement due to the difficulty of direct observation of the velopharyngeal port. This study focused on the correlation between indirect and direct methods of assessing both timing and magnitude of velopharyngeal opening for coarticulation using complementary data from nasometry and a novel technique – high-speed nasopharyngoscopy. Nasometry measures the ratio of distinct nasal and oral cavity outflow to determine the degree of nasality in speech. High-speed nasopharyngoscopy captures images of the nasopharyngeal region and can resolve velar motion during speech. By aligning these data, we can infer the functional changes of the velopharyngeal port and show the correlation between its status and resulting acoustic effects. Preliminary findings replicate previous work on coarticulatory patterns associated with prosodic structure and low versus high vowels. This work will illuminate how variability in velar function affects phonetic outputs.
Real-time imaging of vocal tract configuration in Australian english vowel production
Authors: Proctor Michael I. , Ballard Kirrie , Jin Craig , Gully Amelia , Foster Sheryl , Piyadasa Tharinda , Yue Yaoyao
Published: November 2023

Dynamic phonetic properties of Australian English vowels have been well described in acoustic (Cox, 2006; Elvin et al., 2016) and articulographic studies (Ratko et al., 2023), but the global configuration of the vocal tract during Australian English vowel production has not previously been examined. Midsagittal configuration of the upper airway during production of Australian English vowels was tracked using real-time magnetic resonance imaging (Kennerley et al., 2022) on a 3T scanner (Siemens Magnetom Prisma) using a 64-channel head/neck receiver array coil. Speech audio was simultaneously recorded in-scanner at 16 kHz using a ceramic noise-canceling microphone (Opto-acoustics FOMRI-III). 3D configuration of the vocal tract during sustained productions of the same monophthongs was captured using volumetric imaging of the upper airway at a resolution of 2mm × 2 mm × 2 mm. These data offer new details on configuration of the entire vocal tract and the relationship between articulatory and acoustic targets during production of Australian English vowels.
Effects of horizontal-to-vertical stiffness ratio on the vibration characteristics of a two-mass vocal fold model
Authors: Kurosawa Daiki , Yoshinaga Tsukasa , Iida Akiyoshi
Published: November 2023

In order to evaluate the effects of stiffness ratio of vocal fold on three-dimensional behavior of vocal fold vibration, numerical simulations were performed by using a two-mass vocal fold model with different stiffness ratio of the horizontal and vertical direction. A ratio of the spring constants for the same direction were fixed, while it for the orthogonal directions was changed. To simulate the airflow through the glottis, the one-dimensional Bernoulli’s equation was solved with an equivalent circuit for the compressible flow propagation. The vocal fold shape was represented by a smooth shape with cylindrical masses and tangential faces. The flow separation point was estimated using the boundary layer theory. The results showed that overall fundamental frequency of the vocal folds increased with increasing horizontal stiffness, whereas the vertical stiffness changes had few effects on it. We also found that there were topical conditions in which fundamental frequency rapidly changed with a few changes in stiffness ratio. The stiffness ratio at that time was from 0.80 to 1.08. Before and after the change, there was difference whether the motion trajectory of mass was circular or linear. These results indicate that the vertical stiffness largely affects the oscillation modes of vocal folds.
Silent speech recognition using data augmentation based on a three-dimensional lip model
Authors: Ota Kenko
Published: November 2023

In this study, we proposed a data augmentation method using a three-dimensional model of a speaker's face for machine lip reading, which estimates the content of speech without using speech data. The proposed method converted a speaker's face into a three-dimensional model using DECA (Detailed Expression Capture and Animation), and generated a large amount of learning data by rotating the three-dimensional model in different directions. Then we obtained the facial features around the lips as time series data using dlib, which is an OpenCV module. The time series data is fed into a recognition model. We introduced end-to-end recognition model which is used in continuous speech recognition. The recognition model is based on DeepSpeech2, and we modified the filter size of CNN (convolutional neural network) and the number of layers of BiGRU (bidirectional gated recurrent unit) to adapt to our goal. We evaluated the proposed method on ten ordinary Japanese words. We used the phoneme error rate as the evaluation index. As a result of the evaluation, the error rate of about 0.32 was achieved even for data where the speaker of the evaluation data was not included in the speaker of the training data.
Doubly-spread channel equalization based on channel shortening in mobile underwater acoustic communications
Authors: Tu Xingbin , Yang Shaojian , Xi Jie , Jiang Yulin , Yan Wei , Qu Fengzhong
Published: November 2023

The shallow water environments and the movement of autonomous underwater vehicles contribute to the distortion of acoustic signals in both the delay and Doppler domains. Numerous studies have focused on eliminating the distortion in underwater acoustic communications but have struggled to find an optimal trade-off between performance and computational complexity, rendering them impractical for marine engineering applications. In our research, we propose a channel-shortening equalization scheme based on frequency-domain decision feedback equalization (FD-DFE) to address this issue. This approach leverages FD-DFE to reduce the number of multipaths and decreases the Doppler spread of the channel. A time-domain decision feedback equalization based on recursive least squares (RLS-DFE) is then employed to eliminate residual delay and Doppler spreads. The mismatch between the block- and symbol-wise equalization is minimized by an overlapping subblock structure. Numerical simulations have demonstrated the effectiveness of this scheme. Error-free transmissions with a data rate of up to 6 kbps were achieved in a reservoir experiment between an autonomous underwater helicopter (AUH) and a shore-base receiving node.
Experimental reconstruction of sound fields over large spatial domains
Authors: Fernandez-Grande Efren , Karakonstantis Xenofon , Figueroa-Duran Antonio , Verburg Samuel A.
Published: November 2023

This talk discusses sensing methods and reconstruction techniques for characterizing sound fields over large spatial domains. We focus specifically on reconstructing reverberant soundfields in rooms and enclosures. Two complementary approaches are presented in the talk: on the one hand, we present a method that leverages on modeling the spatio-temporal and statistical properties of enclosed sound fields via wave expansions, enabling to estimate the sound field over a large volume of space. On the other hand, we present a Physics Informed Neural Network, which learns the governing wave equation using a small set of measured data and enables to meaningfully interpolate and extrapolate the sound field to any position where no observations are available. Experiments in real rooms are presented, including an opera hall and an auditoria for oral communication. The experiments successfully demonstrate the volumetric acquisition and three-dimensional characterization of the sound fields. The presented techniques can be of relevance in applications pertaining to immersive and navigable audio, architectural acoustics and heritage preservation.
Single focused-beam acoustical tweezers: Trapping cells in 3-D
Authors: Gong Zhixiong , Li Shiyu , Ma Zhichao
Published: November 2023

Single focused beams have shown great potential in acoustofluidics and medical ultrasound because of their large pressure gradient and acoustic-thermal effect, such as acoustical tweezers and high-intensity focused ultrasound (HIFU) technique. However, the three-dimensional trapping of typical cells is still challenging since cells in water have a positive acoustic contrast factor and will be repulsive from the focus [Gong and Baudoin, Phys. Rev. Applied 18, 044033 (2022)]. In this work, to reverse this positive acoustic contrast factor into negative, we propose to use a cell-friendly medium (made of iodixanol with water) [Augustsson et al., Nat. Commun. 7, 11556 (2016)]. This enables a single focused beam to selectively trap and control cells in 3-D, and more importantly, keeps the manipulated cells with good viability. This work will extend the applications of acoustical tweezers, which may be beneficial to single cell analysis, cellular phenotyping, precise assembly of different cells in tissue engineering, and controlled drug delivery.
Mutual interactions between bulk waves and guided waves in a quadratic nonlinear elastic medium
Authors: del Castillo Albildo Christoph , Zhang Chuanzeng
Published: November 2023

The high sensitivity of nonlinear ultrasonic waves to the early stages of local material deteriorations makes them ideal candidates for nondestructive material characterization. Guided elastic waves, which can be emitted and received on the same surface, expand the possibilities to inspect inaccessible domains to test and monitor existing structures. The pure measurement of the amplitude of the second harmonic has only limited significance, since it is difficult to distinguish between the rather weak material nonlinearity and the nonlinearities from the technical equipment. This can be avoided by mixing two ultrasonic waves of different frequencies, which results in superposed harmonics at these frequencies. In this study, the mutual interactions between bulk waves and guided waves in a quadratic nonlinear elastic medium are investigated by highly efficient computations. In addition, numerical examples for the wave interaction in a finite area with nonlinearity in an otherwise linearly elastic host medium are presented and discussed to explore the effects of individual parameters as well as possible experimental implementation.
RESTARTing the stabilized auditory image: How transient sampling of binaural information supports the emergence of stable auditory scenes
Authors: Stecker G. Christopher
Published: November 2023

The perception of a spatial auditory scene involves the extraction and integration of multiple dynamic and unreliable sensory features (“cues”). Variation in each cue reflects the competing effects of multiple features of the auditory scene—e.g., relevant and irrelevant sound sources. Understanding which cue changes belong together—and to which objects—represents a fundamental challenge to the neural mechanisms of auditory scene perception. RESTART theory suggests a solution: transient, envelope-triggered sampling creates a temporally sparse representation of spatial features. Sparsity minimizes overlap between auditory objects and reduces ambiguity in the face of environmental distortions such as noise and reverberation. Envelope-triggered (“strobed”) sampling stabilizes the auditory image by emphasizing the most reliable cues. Here, we review the key evidence supporting RESTART theory, its neurocomputational mechanisms, and prior efforts to model them. [Work supported by US NIH R01-DC016643.]
A method of timbral equalization for Ambisonics reproduction with irregular loudspeaker configuration
Authors: Du Shanwen , Xie Bosun
Published: November 2023

Ambisonics is a spatial sound reproduction technique based on spatial harmonics decomposition and each order approximation of target sound field. Given a spatial region, Ambisonics is able to reconstruct target sound field accurately up to a frequency limit imposed by Shannon–Nyquist spatial sampling theorem. Above that limit, spatial aliasing in reconstructed sound field occurs, and therefore, timbre equalization in loudspeaker signals is needed to reduce perceived timbre coloration in reproduction. Power equalization is a common and effective method in which the overall power of loudspeaker signals are equalized to be independent of target source direction. The power equalization can be easily implemented in the Ambisonics reproduction with regular rather than loudspeaker configuration. In this study, a method of power equalization for Ambisonics reproduction with irregular loudspeaker configuration is proposed. The fluctuation of overall power of loudspeaker signals with target source direction is controlled within 3 dB by appropriate choice of the decoding coefficients of higher-order spatial harmonics in Ambisonics reproduction. This method is applicable to Ambisonics signals obtained by simulation or microphone array recording. Psychoacoustic experiments indicate that the current method reduces the timbral coloration to some extent while keeps the localization performance in reproduction.
Introduction to Soundwalking—An important part of the soundscape method
Authors: Woolworth David S. , Brooks Bennett , Schulte-Fortkamp Brigitte
Published: November 2023

The soundscape method provides a holistic understanding of the perception by local stakeholders of an acoustical environment. The soundwalk is an important tool of the soundscape technique and is used to measure these perceptions. The core of the soundwalk technique is that local experts experience and evaluate, in context, the acoustical environment where they live, work, and play. The collected soundwalk data can assist in the new design, or an intervention on existing conditions, for an improved quality of life in our communities. This presentation will describe the usefulness of the soundwalk technique and the results which one can obtain. Topics include, planning a soundwalk, ISO Standard 12913 Part 2 procedures, conducting a soundwalk, who are local experts, gathering participants, interaction of participants and problem solving (sound levels and subjective judgments), factors in judgment (sound quality and psychoacoustics), health and healthy soundscapes, interpretation of data, and applications such as ordinances and interventions. Examples of collected soundwalk data, including real-world outcomes are discussed. A soundwalk in Sydney will be conducted following the presentation (about an hour), everyone is invited to participate. After the walk, participants are encouraged to engage in a discussion of the experience, provide additional feedback, and ask questions.
Detections of biological sounds and mapping of acoustic presence of marine organisms
Authors: Akamatsu Tomonari
Published: November 2023

Many species of marine organisms have been known to produce sounds, which represents species or family characteristics. Passive acoustic monitoring is widely applied for the monitoring of presence and distribution of marine mammals since the species-specific sound characteristics are well identified. In the present study, sounds of damselfish, silver croaker as well as biosonar sounds of high frequency cetacean and impulse sounds potentially produced by snapping shrimp were extracted from towed and fixed passive acoustic monitoring systems off Japanese waters. Results show the scattered spots of damsel fish in a coral reef and dense aggregation of silver croakers in specific area. Acoustic distribution of silver croakers and finless porpoises was similar each other that suggested co-existence of prey and predator in highly productive area due to river discharge. Pulse sounds distribution was different from others. Towed passive acoustic monitoring provided snap shot acoustic distributions of multiple species. Day-by-day change of acoustic distribution recorded by fixed passive acoustic monitoring systems could be used for the adaptive management of marine organisms.
If these walls could talk: Investigating bottlenose dolphin habitat use in fiord ecosystems
Authors: Crowe Leah M. , Rayment Will , Stanley Jenni A.
Published: November 2023

Effective management of protected species requires a comprehensive understanding of their ecology. Within the Te Moana o Atawhenua-FiordlandMarine Area (FMA), Aotearoa-New Zealand, two of the four recognized bottlenose dolphin (Tursiops truncatus) sub-populations are considered to exclusively inhabit discrete fiord systems. Opportunistic sightings outside the Patea-Doubtful and Tamatea-Dusky fiord complexes, however, suggest they occupy a larger space than currently recognized. To investigate the presence of bottlenose dolphins in five neighboring fiord systems, passive acoustic monitoring (PAM) was conducted from February 2022 to November 2023. PAM effort included two instrumentation approaches: F-PODs to continuously detect click trains of odontocetes, and SoundTraps to provide broad spectrum recordings (15 of every 30 min, sampling rate: 96kHz). This study discusses the trade-offs between approaches in terms of cost, recording duration, and data collected. In addition, photo-identification of bottlenose dolphins in these neighboring fiords was used to identify the sub-population of individuals. The results demonstrate that bottlenose dolphins are regularly using fiords that are not formally considered part of their range within the FMA. A greater understanding of the spatial ecology of Fiordland bottlenose dolphin sub-populations necessitates consideration of threats and resources both inside and outside of their namesake fiord complexes.
Towards in vivo immunotherapy using high intensity focused ultraosund
Authors: Lajoinie Guillaume , Engelen Yanou , Breckpot Karine , Krysko Dmitri , De Smedt Stefaan , Lentacker Ine
Published: November 2023

High-intensity focused ultrasound (HIFU) has been regarded as an appealing anti-cancer treatment for over a decade. HIFU indeed offers a combination of unique advantages: it is non-invasive and capable of delivering a precise and local thermal or mechanical dose without affecting the surrounding healthy tissue. HIFU is therefore already being applied as a cancer treatment in the clinics, although mostly as a thermal modality. On the other hand, immunotherapy has demonstrated remarkable promise for durable cancer treatment. However, its cost and complexity are prohibitive. Here, we evaluate (moderate) mechanical HIFU treatment and its capacity to induce immunogenic cell death with the aim to achieve immunotherapy treatment, directly in vivo. To that end, we treat a full lummox dish using an automatic scanning setup. Immunogenic cell death is monitored via distinct biomolecular markers (ATP secretion, HMGB1 secretion, calreticulin exposure). Cavitation activity is monitored via passive cavitation detection. Beyond the correspondence between acoustic cavitation and immunogenic cell death, our results also show a major influence of the cell type, namely, standard CT26 or B16F1O cells.
Enhancement of brain hyperthermia via transcranial magnetic resonance imaging-guided focused ultrasound and microbubbles—Heating mechanism investigation using COMSOL
Authors: Xu Zhouyang , Pichardo Samuel , Cheng Bingbing
Published: November 2023

Noninvasive methods for enhancing the brain drug delivery has been pursued for years. Previously we developed a new MR-guided focused ultrasound (FUS)-based technique, which can achieve targeted brain hyperthermia for heat-triggered drug release and simultaneously open the blood–brain barrier safely for drug penetration. However, the underline mechanisms were unclear. This study aimed to explore the mechanisms for the enhanced FUS brain tissue hyperthermia with microbubbles via numerical modeling in COMSOL. The acoustic wave equation was employed to describe the FUS propagation. A bubble dynamics equation was adopted for calculating the stable bubble oscillations under FUS exposures. A modified bioheat transfer equation was utilized to compute the heating, with various heating sources including FUS, microbubble acoustic emission (MAE), and viscous dissipation (VD). The microbubbles were randomly distributed within the focal region. The sonication time was 6s with an initial temperature of 41°C. The average temperature in the focal region were 41.65°C, 42.24°C, 42.98°C, and 43.59°C for FUS alone, FUS + MAE, FUS + VD, and FUS + MAE + VD, respectively. Compared with the FUS alone, both MAE and VD made significant contributions to the heating with additional temperature increases of 47.6% and 67.2%, respectively.
Computational aspects of real-time auralizations of jazz venues
Authors: Scott E. K. Ellington , Braasch Jonas
Published: November 2023

Historically, architectural acoustics has focused on concert halls for European Classical music, even though other genres, including rock, blues, and Jazz, have large groups of followers as well. Additionally, the acoustic requirements for European Classical music differ fundamentally from Jazz and other music. For example, Jazz venues are typically smaller and dryer than a traditional European Classical concert hall. A recent survey showed that reverberation in these venues plays a secondary role to parameters that describe the affordance of a space to allow communication between improvising musicians. This presentation focuses on the unique computational auralization aspects of Jazz venues, including wave-based approaches for smaller enclosures, low-latency requirements, intelligent accompanying systems that can adapt ad-hoc to jazz soloists, and the use of anechoic jazz recordings as source material. The adequacies of different reproduction systems, from higher-order ambisonics and wave-field synthesis to headphone-based systems, will also be discussed. [Work supported by James West Fellowship, Leo and Gabriella Beranek Scholarship, and NSF HCC-1909229.]