bluuebunny/crossref_metadata_2025 huggingface dataset:
Reproducible psychoacoustic experiments and computational perception models in a modular software framework
Authors: Ewert Stephan D. , Dau Torsten
Published: June 2017

Psychoacoustic experiments and auditory models are fundamental elements of hearing research helping to understand human auditory perception. One successful way to apply models has been to use the model as artificial observer, performing exactly the same psychoacoustic experiment as human subjects [e.g., Jepsen et al., J. Acoust. Soc. Am. 124, 422 (2008)]. While the signal processing parts of this and other models are publicly available, reproducible research requires availability of the complete framework including stimulus generation, experimental procedure, and interface to the model. For this, AFC for Matlab/Octave [www.aforcedchoice.com] provides a free and highly flexible framework to design and run psychoacoustic measurements with subjects and computer models. Previous versions of AFC have been used for nearly two decades in several highly ranked psychoacoustic research sites. To foster reproducible research, AFC offers full downward compatibility to the very first version, and the ability to easily overload or add measurement procedures, audio drivers, and models/model interfaces. Here a new version is presented with the above model as a use case. A database of psychoacoustic experiments from numerous publications is established, to provide the stimulus generation of the experiments, methods, and models for exact reproduction of the original work for teaching and research.
An initiative for testability and comparability of binaural models
Authors: Dietz Mathias , Marquardt Torsten , Majdak Piotr , Stern Richard M. , Hartmann William M. , Goodman Dan F. , Ewert Stephan D.
Published: June 2017

A framework aimed at improving the testability and comparability of binaural models will be presented. The framework consists of two key elements: (1) a repository of testing software that evaluates the models against published data and (2) a model repository. While the framework is also intended for physiological data, the planned initial contribution will be psychoacoustical data together with their psychoacoustical testing protocols, as well as existing binaural models from available auditory toolboxes. Researchers will be invited to provide their established as well as newly developed models in whatever programming language they prefer, given the models are compatibility with the proposed interface to the testing software. This entails that the models act as artificial observers, testable with exactly the same procedure as the human subjects. A simple communication protocol based on wav and txt-files is proposed because these are supported by every programming environment, and are able connect models and testing software of any programming language. Examples will illustrate the principle of testing models with unaltered signal processing stages on various seminal data sets such as tone detection in so-called double-delayed masking noise, or lateralization of ¾-period delayed noise and sounds with temporally asymmetric envelopes.
Development and dissemination of computational models for physiology and psychophysical predictions
Authors: Carney Laurel H.
Published: June 2017

This talk will present lessons from our experience in publishing and sharing computational models for physiological and psychophysical responses. Our physiological models have included rather comprehensive and nonlinear phenomenological descriptions of auditory-nerve responses to complex sounds, and simpler linear models for brainstem and midbrain responses. Using ensembles of single-neuron models to estimate population responses enables psychophysical predictions based on different aspects of sub-cortical representations. Examples of psychophysical models that we have pursued include level discrimination and diotic and dichotic masked detection of tones. Some of the challenges inherent in this type of work will be discussed. [Work supported by NIH-R01-001641 & -010813.]
An investigation of passive type hearing protection in human and animals by their auricles by diverting natural drainage of rain water along facial features into the ear canal
Authors: Biswas Amitava
Published: June 2017

Many textbooks in human auditory system begins with the external ear and basically describe the auricle as a collector of sound. In this study, we have explored the utility of the auricle to protect the external ear canal from environmental factors such as rain shower or sand storm. A model of human head of typical dimensions was held in upright position inside a bath tub. A shower head was positioned directly above the model head. One ear of the model was sliced off. Each ear canal was provided internally a tube of about 8 mm diameter connected to a collecting bottle of about 500 cc capacity. The shower head output was about eight liters of water per minute. The results suggest that the impaired ear is more vulnerable to water entry compared to the unimpaired ear of the model. Therefore, another vital necessity of evolution of the external ear may have been environmental protection, in addition to collection of sound energy. Generalization of the data for other common animals will be discussed.
Measurements of the acoustic feedback path of hearing aids on human subjects
Authors: Sankowsky-Rothe Tobias , Blau Matthias
Published: June 2017

Feedback is a problem in hearing aids which will cause signal degradation and reduce the maximum applicable gain. More specifically, the advantages of open fittings (e.g., minimizing the occlusion effect) are limited by acoustic feedback. Feedback cancelation algorithms are used to overcome these limitations. For the development of such algorithms, the acoustic feedback path of the hearing aid must be known. The acoustic feedback path is not only affected by the outer sound field but by the individual anatomy and physiology as well. In order to quantify these different influences, feedback path measurements were performed on 20 human subjects. The measurements included different static conditions as well as dynamic ones (i.e., repetitive movements were performed during the measurement). Since the sound pressure level must be limited in measurements on human subjects, a valid identification of the feedback path is difficult in many cases, due to a low signal to noise ratio. Therefore, all measurements were performed reciprocally in addition to the direct measurements. Results show that yaw movements only have a small influence on the acoustic feedback path, whereas changes of the outer sound field can have a substantial impact on the feedback path.
How to improve a hearing aid fitting based on idiosyncratic consonant errors
Authors: Abavisani Ali , Allen Jont b.
Published: June 2017

The goal of this study is to quantify a given hearing aid insertion gain using a consonant recognition based measure, for ears having sensorineural hearing loss. The basic question addressed is how a treatment impacts phone recognition, relative to a normal-hearing insertion gain. These tests are directed at (1) fine-tuning a treatment, with the ultimate goal of improving speech perception, and (2) to identify when a hearing level based treatment degrades speech recognition. Eight subjects with hearing loss were tested under two conditions: Flat-gain and a Treatment insertion gain based on subject's hearing level. The speech corpus consisted of consonant-vowel tokens at different signal to speech-weighted noise (SNR) conditions, presented at subjects’ most comfortable level. The tokens used in this study were selected from those having less than 3% error at -2 [dB] SNR, from 30 Normal Hearing subjects. The Treatment caused token score to improve for 31% of the trials and decrease for 12%. An analysis method was devised to identify degraded tokens for individual hearing impaired ears, based on sorting the tokens according to their error. By comparing sorted errors across experiments, the effect of the treatment could be accurately evaluated, providing precise characterization of idiosyncratic phone recognition.
A fast test for determining the edge frequency of a dead region
Authors: Schlittenlacher Josef , Turner Richard E. , Moore Brian C.
Published: June 2017

The presence and edge frequency, fe, of a dead region in the cochlea can be diagnosed using psychophysical tuning curves (PTCs). When the signal frequency, fs, falls in a dead region, the tip of the PTC lies close to fe, rather than close to fs. However, measurement of PTCs is time consuming, limiting their application in clinical practice. We have developed a fast test based on Bayesian active learning. Instead of estimating an entire PTC, we estimate parameters of an individual hearing model, including fe. The task is to detect a fixed signal in the presence of a masker whose level and frequency vary across trials. After each trial, the next masker level and frequency are chosen to produce maximum reduction of the uncertainty about the parameters. The results for four participants tested so far were close to those obtained using “fast” PTCs. The Bayesian procedure has two advantages compared to PTCs: it allows quantification of the reliability of the subjects, estimated from the standard deviation of a cumulative Gaussian fitted to the psychometric function; and masker levels and frequencies can be restricted to being close to the estimated minimum of the PTC, avoiding unnecessary presentation of high level sounds.
Sound source localization as a multisensory process: The Wallach azimuth illusion
Authors: Pastore M. Torben , Yost William
Published: June 2017

An auditory spatial illusion, introduced by Wallach (1939, 1940) and recently revisited by Brimijoin and Ackeroyd (2012), occurs when both listeners and sounds rotate. Rotating a sound, around the listener in the azimuth plane at twice the rate of listeners’ head turns, can elicit the sensation of a static sound source located either in front of the listener when the sound is originally presented from behind, or behind the listener when the sound is originally presented in front. We investigated this auditory illusion when listeners were rotated at constant velocity in a rotating chair with eyes open, for bandpass noises presented from an azimuthal ring of 24 loudspeakers. For noises that were likely to generate front-back confusions, the illusion of a stationary sound was robust, especially for low-frequency sounds. On the contrary, for noises that were unlikely to produce front-back confusions, listeners reported the sound rotating around them on the azimuth plane. These observations are predicted by a simple model, based on Wallach's original multisensory explanation, combined with estimates of the availability of spectral cues that may be used to disambiguate front/back confusions. [Partially support by a grant from the National Institute on Deafness and Other Communication Disorders, NIDCD.]
Perceived amount of reverberation consistent with binaural summation model
Authors: Ellis Gregory M. , Zahorik Pavel
Published: June 2017

Although perceived amount of reverberation (PAR) is known to be dependent on the physical amount of reverberation present at the two ears, the extent to which this information may be combined across the ears is not well understood. Previous work using virtual auditory space techniques has demonstrated that when physical reverberation is reduced in the ear nearest a sound source while the contralateral ear is left unchanged, listeners do not report a change in PAR. Reducing physical reverberation equally in both ears, however, elicits a decrease in PAR. To better understand this phenomenon, the present study examines how PAR is affected by three additional listening conditions: scaling the contralateral ear while leaving ipsilateral fixed, scaling the contralateral ear only with no ipsilateral signal (monaural), and scaling the ipsilateral ear only with no contralateral signal (monaural). This study also examines how PAR is affected by an increase in physical reverberation present at the ears in the two listening conditions from the original study. Behavioral results are consistent with a binaural summation model that combines reverberant sound power from the two ears.
Effect of frequency region on binaural interference for interaural level differences
Authors: Rosen Beth , Goupell Matthew
Published: June 2017

Binaural interference occurs when a spectrally remote diotic interferer affects the ability to detect changes in interaural differences in the target. For interaural time differences, the magnitude of binaural interference depends on the target and interferer locations. For interaural level differences (ILDs), it is unclear if the magnitude of binaural interference depends on target and interferer location. ILDs are highly frequency dependent; ILDs become larger for increasing frequency for sources in the free field. Therefore, we hypothesized that binaural interference for ILDs would be frequency dependent, and that both target and interferer frequency would affect thresholds. In ten young normal-hearing listeners, we measured ILD discrimination thresholds using single tones, once with no interferer and then in the presence of a diotic interferer. We tested five frequencies: 500, 1000, 2000, 4000, and 8000 Hz. Each combination of target and interferer frequency was tested, resulting in 25 conditions. ILD thresholds for targets alone were frequency dependent. Binaural interference occurred for ILDs, and the magnitude changed depending on the target and interferer location. These data will contribute to better understanding of across-frequency ILD processing, which is important for bilateral cochlear-implant users who rely on ILDs to localize sounds. [Work supported by NIH R01-DC014948 (M.J.G.).]
Adaptation in distance perception induced by audio-visual stimuli with spatial disparity
Authors: Hladek Lubos , Seitz Aaron , Kopco Norbert
Published: June 2017

Simultaneous presentation of audio-visual stimuli with disparity leads to perceptual shifts in judgments of the stimulus auditory components (ventriloquism effect, VE). The shifts can persist even to auditory stimuli presented alone (ventriloquism aftereffect, VA). A previous study showed asymmetrical VE and VA for visual adaptors presented closer vs. further than the auditory components [Hládek et al. (2014), Visual calibration of auditory distance perception, ARO #37 Abstract PS-614]. In that study, a brief flash of light (visual adaptor) or noise burst (auditory component) were presented in front of the listener at distances 0.4-2.6 m in a small reverberant room, with visual adaptor 30% closer or further than the auditory component. Here, a new analysis of the results is presented, showing that much of the previously observed asymmetries between the two directions of shift (visual-closer vs. visual-farther) can be accounted for by referencing responses to the pre-adaptation baseline, and by scaling the data with respect to V-Aligned responses using the actual physical disparity of the auditory and visual component. However, asymmetry still persists for the VA data and VA buildup, suggesting that different neural substrates underlie VA and VE in the distance dimension. [Work supported by APVV-0452-12 and EU H2020-MSCA-RISE-2015 grant 691229.]
The roles of inhibition and adaptation for spatial hearing in difficult listening conditions
Authors: Lestang Jean-Hugues , Goodman Dan F.
Published: June 2017

The computation of binaural cues such as the Interaural Time Difference (ITD) and Interaural Level Difference (ILD) by the auditory system is known to play an important role in spatial hearing. It is not yet understood how such computations are performed in realistic acoustic environments where noise and reverberations are present. It has been hypothesized that robust sound localization is achieved through the extraction of the ITD information in the rising part of amplitude modulated (AM) sounds. Dietz et al. (2013) tested this hypothesis using psychoacoustics and MEG experiments. They presented AM sounds with ITDs varying during the course of one AM cycle. Their results showed that participants preferentially extracted the ITD information in the rising portion of the AM cycle. We designed a computational model of the auditory pathway to investigate the neural mechanisms involved in this process. Two mechanisms were tested. The first one corresponds to the adaptation in the auditory nerve fibers. The second mechanism occurs after coincidence detection and involves a winner-take-all network of ITD sensitive neurons. Both mechanisms qualitatively accounted for the data, consequently we suggest further experiments based on similar stimuli to distinguish between the two mechanisms. Dietz et al. (2013), “Emphasis of spatial cues in the temporal fine structure during the rising segments of amplitude-modulated sounds,” Proc. Natl. Acad. Sci. 110(37), 15151-15156.
Preserving spatial perception in reverberant environments using direct-sound driven dynamic range compression
Authors: Hassager Henrik G. , May Tobias , Wiinberg Alan , Dau Torsten
Published: June 2017

Fast-acting hearing-aid compression typically distort the auditory cues involved in the spatial perception of sounds in rooms, due to the enhancement of low-level reverberant energy portions of the sound relative to the direct sound. The present study investigated the benefit of a novel direct-sound driven compression scheme that adaptively selects appropriate time constants to preserve the listener’s spatial impression. Specifically, fast-acting compression was maintained for time-frequency (T-F) units dominated by the direct sound while the compressor was linearized via longer time constants for T-F units dominated by reverberation. This novel compression scheme was evaluated with normal-hearing listeners who indicated their perceived location and distribution of virtualized speech in the horizontal plane. The results confirmed that both independent compression at each ear and linked compression across ears resulted in more diffuse and broader, sometimes internalized, sound images as well as image splits. In contrast, the novel linked direct-sound driven compressor provided the listeners with a similar spatial perception obtained with linear processing that served as a reference. Independent direct-sound driven compression created a sense of movement of the sound between the two ears, suggesting that preserving the interaural level differences via linked compression is advantageous with the proposed direct-driven compression scheme.
Interaural level difference-based model of speech localization in multi-talker environment
Authors: Toth Peter , Kopco Norbert
Published: June 2017

Horizontal localization is based on extraction of the interaural time and level differences (ITD, ILD). Even in complex scenes with multiple talkers and reverberation, the auditory system is remarkably good at estimating the individual talker locations. Several previous models proposed mechanisms that stressed the importance of ITD in the localization process. Here, we examine whether azimuth estimation in complex scenarios can be based solely on ILD. We implemented a model (based on Faller and Merimaa, 2004) in which azimuth estimation was based on ILDs of signal parts with high interaural correlation and with spectral profile matching that of the target. Comparison with experimental data (Kopco et al., 2010) showed that highly correlated parts of the signal, if available, provide reliable ILD estimates sufficient for precise target localization. However, for lateral target positions, at which the target dominates one ear but not the other, interaural correlation was too low to guide ILD extraction. In such cases, a new model based on finding maximum ILD provided good estimates even if maskers dominated in the worse ear. The combined model predictions matched the experimental data with target locations between -50° and 50° and for 4 maskers in reverberation. [Work supported by APVV-0452-12, H2020-MSCA-RISE-2015 #691229.]
Binaural detection of a Gaussian noise burst target in the presence of a lead/lag masker
Authors: Braasch Jonas , Pastore M. Torben , Zhou Yi
Published: June 2017

When a leading stimulus is followed shortly thereafter by another similar stimulus coming from a different direction, listeners often report hearing a single auditory event at or near the location of the leading stimulus. This is called the precedence effect (PE). We measured masked detection thresholds for a noise target in the presence of a masker composed of (1) a lead/lag noise pair with the lead ITD set the same or opposite to the target, (2) a diotic masker, and (3) a dichotic pair of decorrelated noises. If the PE results in actual elimination of the lag stimulus, we would expect lower masked thresholds when the lead ITD is opposite to that of the target, as predicted by spatial release from masking. Results show that for small lead/lag delays, detection thresholds were similar to those for the diotic masker, regardless of whether the lead ITD was the same or opposite to that of the target. For longer lead/lag delays, which are unlikely to elicit the PE, thresholds approached those measured for dichotic maskers composed of two decorrelated noises. An extended EC model is used to simulate the psychophysical results. [Work supported by NSF BCS-1539276 and NSF BCS-1539376.]
Rapid learning of sound schema for the cocktail party problem
Authors: Woods Kevin
Published: June 2017

Auditory scene analysis depends on knowledge of natural sound structure, but little is known about how source-specific structures might be learned and applied. We explored whether listeners internalize “schemas”—the abstract structure shared by different occurrences of the same type of sound source—during cocktail-party listening. We measured the ability to detect one of two concurrent “melodies” that did not differ in mean pitch (nor in timbre), ensuring that only the structure of these melodies over time could be used to distinguish them. Target melodies were cued by presenting them in isolation before each mixture, transposed to avoid exact repetition. The task was to determine if the cued melody was present in the subsequent mixture. Listeners performed above chance despite transposition between cue and target. Particular melodic schemas could recur across a subset of trials within a block, as well as across blocks separated by epochs in which the schema was absent. Recurrence across trials within a block facilitated target detection, and the advantage grew over the experiment despite intervening blocks, suggestive of learning. The results indicate that rapid and persistent internalization of source schemas can promote accurate perceptual organization of sound sources that recur intermittently in the auditory environment.
Perfect and broadband acoustic absorption in deep sub-wavelength structures for the reflection and transmission problems
Authors: Romero-García Vicente , Jiménez Noé , Pagneux Vincent , Groby Jean-Philippe
Published: June 2017

The mechanisms to achieve perfect acoustic absorption by sub-wavelength structures in both reflection and transmission problems are reported. While the mechanism consists in critically coupling a single resonance independently of its nature in the reflection problem, the mechanism becomes more complicated in the transmission problem. To tackle these issues, we use asymmetric interacting resonators, whose interaction leads to the perfect absorption condition. The analyzed system consists in a panel with a periodic distribution of thin slits, the upper wall of which being loaded by Helmholtz Resonators. The propagation in the slit is highly dispersive due to the presence of the resonators, producing slow sound conditions and down-shifting the slit resonance to low frequencies. By controlling the geometry of the resonators, the visco-thermal losses are tuned to compensate the leakage of the system and fulfill the perfect absorption condition. In the case of the reflection problem, a single resonator is enough to obtain the perfect absorption. However, in the case of transmission, using an array of identical Helmholtz resonators only quasi-perfect absorption can be obtained. A possible solution is the use of double interacting resonators, one acting as reflecting wall for the previous one. This procedure can be iteratively repeated and one can design perfect and broadband acoustic absorbers based on the rainbow trapping mechanism.
Periodic resonance effect for the design of low frequency acoustic absorbers
Authors: Dupont Thomas , Leclaire Philippe , Panneton Raymond , Umnova Olga
Published: June 2017

This presentation examines a perforated resonant material, in which the principal perforations comprise a network of periodically spaced dead-end pores. This material can show good sound absorption at low frequencies, particularly given its relatively small thickness. In a recent study, this kind of material was modeled by an effective fluid approach which allowed low frequency approximations. At low frequency, it was shown that the periodic array of dead-end pores increases the effective compressibility without modifying the effective dynamic density. Thereby, the resonance frequency of the material is reduced in a significant way, as is the frequency of the first sound absorption peak. Moreover, a bandgap effect occurs at high frequency for the sound transmission problem. This study suggested a new concept of micro-structure for designing low-frequency resonant acoustic absorbers. A transfer matrix approach is now proposed to model and optimize such a concept. Prototypes have been made with 3D printing and tested in an acoustic tube for sound absorption and sound transmission loss. The resonant periodicity effects have been observed, and the measurements compare well with the predictions of the transfer matrix model. Finally, an optimization of the microstructure is proposed.
Negative refraction experiments in soft 3D metafluids
Authors: Brunet Thomas , Kovalenko Artem , Tallon Benoit , Mondain-Monval Olivier , Aristégui Christophe , Poncelet Olivier
Published: June 2017

Physics of negative refraction has been intensively studied since the 2000s. Negative refraction is usually evidenced by a Snell’s law experiment using a prism shaped negative-index metamaterial wedge. The first experimental verification of negative index of refraction was reported in 2D resonant structures at microwave frequencies [1]. A few years later, negative refraction was demonstrated in 2D and 3D resonant optical metamaterials [2]. In acoustics, the first experimental demonstration of negative refraction was reported in 3D (non resonant) phononic crystals at ultrasonic frequencies [3]. However, 3D acoustic (random) metamaterials should also offer the possibility to explore this exotic phenomenon since the first 3D locally resonant metamaterial with a negative index has been recently demonstrated [4]. In this talk, we will report on negative refraction experiments performed in these soft 3D metafluids composed of macro-porous micro-beads randomly dispersed in a water-based gel-matrix. Negative refraction will be demonstrated by the negative deflection of an ultrasonic beam outgoing from a prism shaped metafluid in a water tank experiment. [1] Shelby et al., Science 292, 77 (2001). [2] Valentine et al., Nature 455, 376 (2008). [3] Yang et al., Phys. Rev. Lett. 93, 024301 (2004). [4] Brunet et al., Nat. Mater. 14, 384 (2015).
Scattering from a fluid cylinder with strain-momentum coupled constitutive relations
Authors: Muhlestein Michael B. , Goldsberry Benjamin M. , Haberman Michael R.
Published: June 2017

Many important applications of acoustics are associated with the principle of scattering. For example, biomedical ultrasound and sonar both make use of acoustic field scattering for localization, imaging, and identification of objects. While the theory of acoustic scattering from fluid and elastic materials is well established and has been validated with numerical and physical experiments, no work has been published to describe scattering from a more general class of acoustic materials known as Willis materials. Willis materials are characterized by a bulk modulus and mass density as well as a vector that couples the pressure-strain relationship with the momentum density-particle velocity relationship. The coupling vector is the result of microstructural asymmetry. We present a theoretical description of acoustic scattering of a plane wave incident upon a cylinder exhibiting weak Willis coupling using a perturbation approach. The scattered field depends upon the orientation of the Willis coupling vector and is therefore anisotropic despite the symmetry of the geometry. The analytical model is validated through comparison with a finite element-based numerical experiment.
Extreme impact mitigation by critical point constraints on elastic metamaterials
Authors: Harne Ryan L. , Bishop Justin , Urbanek Daniel C. , Dai Quanqi , Song Yu
Published: June 2017

A critical transition occurs between pre- and post-buckled configurations of lightly-damped structures where the relative proportions of dissipative and elastic forces may reverse, theoretically giving rise to large effective damping properties. This paper describes computational and experimental studies that investigate such fundamental theory and principles. It is found that impact mitigation capabilities of elastic metamaterials are significantly enhanced by critical point constraints. The results of one-dimensional drop experiments reveal that constrained metamaterials reduce impact force and suppress rebound effects more dramatically than conventional damping methods, while constraints nearer to critical points magnify the advantages. When embedded into distributed structures as in conventional applications, it is found that constrained metamaterials provide superior impact mitigation capabilities than solid dampers applied at the same locations. All together, the results show that critical point constraints on elastic metamaterials provide new directions for the control and suppression of impact energy with effectiveness exceeding that achieved by solid dampers having the same bulk geometry.
Efficiency of an absorber involving a nonlinear membrane driven by an electro-acoustic device
Authors: Bryk Pierre-Yvon , Bellizzi Sergio , Côte Renaud
Published: June 2017

Great attention has been recently paid to employing nonlinear energy sink (NES) as an essential nonlinear acoustic absorber rather than Helmholtz absorbers. NES are based on the principle of the “Targeted Energy Transfer” (TET) that allows to transfer the energy from a primary acoustic field to the NES. In this paper, an hybrid electro-acoustic NES (hNES) is described. It is composed of an latex membrane with one face (exterior) coupled to the acoustic field (to reduce) and the other one enclosed. The enclosure includes a feedback loop composed of a microphone and a loudspeaker that control the pressure difference at the level of the membrane. Due to the hardness behavior of the membrane in non-linear deformation, the hNES can synchronize its resonance with one of the resonances of the acoustic field greater than the linear resonance of the hNES. It allows to bring out the TET toward the hNES and thus reduce noise. The feedback loop tunes the linear resonance frequency of the hNES at low level, which is a key factor for the triggering threshold of the TET. An experimental study of the hNES will be presented including TET regime characterization and influence analysis of the feedback gain.
Effects of error in a subordinate oscillator array
Authors: Sterling John A. , Vignola Joseph F. , Ryan Teresa J. , Miller William , Glean Aldo A.
Published: June 2017

Existing research has shown that the response of a single degree of freedom resonant system can be modified by the attachment of sets of substantially smaller resonators. Such arrays of attachments, known as subordinate oscillator arrays, can increase the apparent damping of the primary structure, and the property distributions can be selected such that the collective effects result in a response of the primary resonator that is similar to an electrical band-rejection filter. Other prior work with this system has indicated high sensitivity to disorder in the individual attachment properties such that even 0.1% variation is likely to cause undesirable effects in the overall system response. Such levels of variation well below 1% are easily attributable to typical manufacturing tolerances, environmental influences, and degradation factors. This work presents experimental results of a set of prototype subordinate oscillator arrays produced with high precision additive manufacturing techniques so as to prescribe different levels of variation.
Damping treatment of optical breadboards
Authors: Ryaboy Vyacheslav
Published: June 2017

Vibration damping of honeycomb optical tables had been subject of significant research and development efforts during several decades. These efforts resulted in tuned and broadband damping treatments, as well as active damping system that found extensive practical applications. Smaller optical platforms (breadboards) are often used for vibration-sensitive applications due to dearth of laboratory space and increased sensitivity of small optical instruments. Relatively massive damping devices that work for large tables are not applicable to smaller (usually 5 to 10 cm thick) breadboards. This paper describes a new method for damping resonance vibration of optical breadboards with honeycomb cores. The method makes use of typical modal geometry of orthotropic laminated plates by integrating a layer of highly damped material between two surfaces making it to work in shear. Physical principle, optimization procedure, practical designs, implementation, and test results of damped breadboards are presented.
Multimodal investigation of speech production featuring real-time three-dimensional ultrasound
Authors: Lulich Steven M.
Published: June 2017

Real-time three-dimensional ultrasound offers new opportunities to investigate the spatial and temporal complexities of speech production, but ultrasound by itself continues to be limited in significant ways because (typically) only one surface of the vocal tract can be imaged: the tongue. Nevertheless, many of these limitations can be overcome by appropriately time-aligning and spatially registering ultrasound volumetric images with additional data streams, such as lateral webcam video, acoustic recordings, and digitized palate impressions. One method by which this may be accomplished makes use of a new open-source toolbox for MATLAB, called “WASL,” which was originally designed specifically for real-time three-dimensional ultrasound, but is now extensible to other biomedical imaging modalities, including MRI, CT, and two-dimensional ultrasound. Examples from a study of rhotic sound production illustrate how multimodal investigations of speech production featuring real-time three-dimensional ultrasound may be carried out using WASL.
New trends in visualizing speech production
Authors: Perry Jamie
Published: June 2017

Most dynamic magnetic resonance imaging of the levator veli palatini (levator) muscle has been limited to studies using sustained phonation (Yamawaki et al. 1996; Ettema et al. 2002; Tian et al., 2010a, 2010b; Kollara and Perry, 2013). Dynamic MRI sequences at faster imaging speeds using word-level productions have been described along the midsagittal image plane (Sutton et al., 2009; Bae et al., 2011; Scott et al., 2013) and oblique coronal image plane (Perry et al., 2013b, 2013c; Scott et al., 2013). The purpose of this presentation is to describe methods for analyzing the velopharyngeal mechanism and velar muscles during rest and speech production using MRI. This presentation will demonstrate a potentially useful technique in dynamic MRI that does not rely on cyclic repetitions or sustained phonation and can provide dynamic information related to muscle function. Innovative techniques in imaging and interpreting dynamic MRI of velopharyngeal function during speech will be described. It is expected these developments will provide insights that will improve clinical methods in resonance assessments among children born with cleft lip and palate.
Predicting velum movement from acoustic features—A regression approach
Authors: Zhang Hong
Published: June 2017

Although acoustical methods have been widely used in the nasality literature, a direct link between the acoustical measurements and velum movement during speech production is yet to be established. In this study, we propose a model through which the vertical movements of the velum are inferred from an acoustic feature set. An X-ray Microbeam data set collected at University of Tokyo are used for the modeling. The data recorded the vertical movements of the velum of 11 American English speakers saying both isolated words and sentences. Velum positions are recorded from tracing a metal pallet placed on top of the velum. 40 MFCC (Mel-frequency Cepstral Coefficient) features are extracted from the accompanying acoustic signal at each time frame. MFCCs of ten frames before the current frame, together with the current frame, consist of the feature vector for predicting the velum movement of the current frame. Elasticnet regression is used to reduce the dimensionality of the feature vector. In general, MFCCs from higher frequencies are penalized during model selection. The selected features are then fitted to a stepwise logistic model. For each individual speaker, the inferred velum movements in the validation set are a good fit to the actual observation as judged by the high accuracy in identifying locations of peaks and valleys and small deviance from the response. However, there exists large inter-speaker variation in terms of both movement pattern and model performance.
Maintaining vowel distinctiveness in children with Steinert Myotonic Dystrophy: An ultrasound study
Authors: Bellavance-Courtemanche Marie , Trudeau-Fisette Pamela , Prémont Amélie , Turgeon Christine , Menard Lucie
Published: June 2017

Speech production entails appropriately timed contractions of many muscles. Steinert myotonic dystrophy, a neurodegenerative disease that causes muscle weakness and difficulties in muscle relaxation after muscle contraction, frequently affects orofacial articulatory dynamics leading to decreased speech intelligibility. We aimed to investigate the articulatory and acoustic characteristics of cardinal vowels produced by children with Steinert disease. We recruited fourteen 6- to 14-year-old French-speaking children diagnosed with Steinert disease and 14 aged-matched typically developing children. They were asked to produce repetitions of the vowels /i a u/ in consonant-vowel (CV) contexts. A synchronized ultrasound, Optotrak motion tracking system, and audio recording system was used to track lip and jaw displacement as well as tongue shape and position. Duration and formant values were also extracted. The Euclidean distance between vowels, in the formant space, was reduced in children with Steinert disease compared to the control children. Different patterns of articulatory contrasts were observed among the children, with some of them using more tongue contrasts than lip contrasts. Intelligibility tests conducted with adult listeners on a subset of the data show that some patterns are related to higher intelligibility scores than others.
Higher-order estimation of acoustic intensity
Authors: Lawrence Joseph S. , Gee Kent L. , Neilsen Tracianne B. , Sommerfeldt Scott D.
Published: June 2017

The phase and amplitude gradient estimator (PAGE) method [D. C. Thomas et al., J. Acoust. Soc. Am. 137, 3366-3376 (2015)] can be used to increase the bandwidth of complex acoustic intensity estimates obtained with multi-microphone probes. Despite the increased bandwidth, errors arise when using this method, which is based on linear least-squares gradients, in non-planar fields. Examples of non-planar fields include the acoustic near field of a radiating source or near a null in a standing-wave field. The PAGE method can be improved by using a Taylor expansion to obtain higher-order estimates of center pressure, pressure amplitude gradient, and phase gradient. With a sufficient number of microphones, the higher-order method is shown to improve the bandwidth of both the active and reactive intensity estimates. Additionally, this method can be used to estimate the spatial dependence of intensity across the extent of the probe. [Work supported by the National Science Foundation.]
Dual accelerometer vector sensor mounted on an autonomous underwater vehicle (AUV)—Experimental results
Authors: Santos Paulo J. , Felisberto Paulo , Zabel Frederich , Jesus Sergio , Sebastião Luís
Published: June 2017

In seismic geo-acoustic exploration, the use of ships equipped with long streamers is of major concern due to the complexity of the operations. The European project WIMUST aims to improve the efficacy of actual geo-acoustic surveys through the use of AUVs towing short streamers. A Dual Accelerometer Vector Sensor (DAVS) was developed in order to complement the streamer’s data, allowing for the reduction of their size and facilitating the operation of the WiMUST distributed configuration. Each DAVS consists of two tri-axial accelerometers and one hydrophone aligned along a vertical axis. This configuration has the ability to cancel or significantly attenuate the direct and the surface reflection paths, which are undesirable in seismic imaging. Calibration tests with the DAVS have already been performed; this paper presents experimental results on the estimation of azimuthal directions when the DAVS is in motion. Signals in the 1-2kHz band were emitted by a source deployed in a shallow pond at 1.5m depth and acquired by the DAVS mounted on a MEDUSA class AUV, which was following a pre-programed path with a 0.26m/s nominal speed. The azimuth estimates are coherent with the MEDUSA trajectories even in curved paths where the thruster noise increases.
Ira Dyer advisor to the Navy
Authors: Cox Henry
Published: June 2017

Among his many activities, Ira Dyer was a valued consultant to the Navy. He was called to participate as a charter member of the Submarine Superiority Technical Advisory Group established by Admiral De Mars in 1995. He served on this and other panels for more than 15 years. He made many important contributions to the submarine force, particularly relating to ocean acoustics pertaining to operations, and structural acoustics pertaining to submarine design. Ira’s ability to penetrate difficult problems, simplify and explain was unique. When Ira spoke, every one listened. Comments on his contributions and recollections of his colleagues are presented.
Contrapuntal design: The influence of Bertram Y. Kinzey, Jr., on architectural pedagogy at the University of Florida
Authors: Gold Martin A.
Published: June 2017

Bertram Kinzey introduced modes of analysis, conceptualization, and exploration, as a dedicated and productive researcher, author, teacher, architect, consultant, and musician that were transformative and continue to reverberate internationally through the work of his students. Bert’s insightful theoretical and practical relationships between music, acoustics, and architecture were drawn from his reflective approach to teaching and refined through active practice. Perhaps foundational to his educational contribution, is his interest and talent as an organist and organ builder leading to his use of “contrapuntal” to describe the interaction of music and architecture—new notes overlapping those lingering in the space and time of reverberance. Overlapping, independent, yet harmonizing elements might also describe Bert’s approach to architectural design as a theoretical construct; an integrative process; and as a measure of great architecture. Contrapuntal thinking is well known in literature and music but is just emerging in architecture. Bert introduced this important idea—among many others at the University of Florida—through his writings and tenure as a UF professor. This paper discusses Bert’s ‘contrapuntal thinking’ and the subsequent influence on architectural education through a recent graduate studio project for a new arts park and concert hall for the community of Sarasota, Florida.
A living example—An attitude towards sustainable living
Authors: Chiang Weihwa
Published: June 2017

A sustainable built environment aims for minimizing environmental impact while maintaining healthy living. The Acoustics and Environmental Technology programs started by Professor Bertram Y. Kinzey, Jr., at the University of Florida were established with architecture design integration in mind. The programs and Professor Kinzey’s influence were not limited to the books and theories but also to the lives of his students. His remarkable work, Bailey Hall at Broward Community College, the University Auditorium renovation at UF and classroom are valuable memories to students who sat in them daily for decades. His passive design signature house in Gainesville is another unforgettable inspiration for students. It was where he successfully applied sustainable design concepts and theories in reality in the early 1960s. These are evidence of how he inspires students by his life as a solid practitioner as well as a modern “Renaissance man.” Despite his retirement from UF, his influence has been passing on and spread around the world continually. His pass-through guidance has been followed in teaching, research, design and planning projects with a holistic approach. It not only peruses technical excellence with thoughtful social-economic concerns but heavily relies on “Kinzeian” humanity and attitude for sustainable living and architecture.
Studying with Professor Bertram Y. Kinzey, Jr., in the University of Florida, School of Architecture Environmental Technologies Option and its impact on my professional career
Authors: Ramos Bruno E.
Published: June 2017

Professor Kinzey was instrumental in the careers of many professionals. He challenged students daily, pushed us to think “outside the box” and considered the integration of sustainable design principles in buildings long before LEED ever existed. I recall him saying “the old tests are in the library, you may go and review them... as it’s my job to test your knowledge in different ways.” He encouraged his students to gain the knowledge and experience to derive the answers. The scale models we built to measure and study acoustics and lighting within spaces also influenced my professional career. We applied those same concepts in marine architecture using a “Kinzey type” solution by building a scale model to determine the requirements and force needed to haul a large barge out of shallow water. Lastly, I am personally grateful to Professor Kinzey for stimulating the pursuit of excellence in his students which helped me to pass the A.R.E. and LEED licensing, at a very young age, in my first attempt. Professor Kinzey has had a lifetime of significant work in Acoustics and has influenced thousands of students in a profound manner.