bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of the predictive accuracy of different computational models of auditory perception
Authors: Davies-Venn Evelyn E. , Mamun Nursadul , Hossain Md. , Kwan Timothy , Putman Melanie , Zilany M. S. A.
Published: April 2019

Computational models of auditory perception offer a time-efficient method of assessing the effects of distortion on speech perception. Several objective metrics have been proposed to predict speech intelligibility, especially when speech is obscured by the presence of background noise. Novel approaches to full-reference and reference-free speech intelligibility metrics have emerged in recent years, but deciphering the best metric for predicting speech intelligibility still requires investigation. This study assessed the predictive accuracy of several reliable, full, and reference-free speech intelligibility metrics. Speech perception scores were measured on listeners with normal hearing and hearing loss in quiet and noise. Acoustic recordings were made of the presented speech stimuli and combined with a computational model of the auditory nerve to simulate behavioral scores using several established metrics such as the STOI, NSIM, SRMR, SII, SNRloss, and BSIM. The estimated speech scores were correlated with behavioral speech recognition scores to assess predictive accuracy of the model simulations. Several of the predicted scores correlated well with behavioral scores. Evaluation of individual phonemes revealed differential sensitivity of the metrics across different phonemic classifications.
Listening to the songs of the universe: How vibration control for the laser interferometer gravitational-wave observatory (LIGO) allows us to measure ripples in the fabric of space
Authors: Lantz Brian
Published: April 2019

In 2015, humanity made the first detection of gravitational waves from the violent collision of two black holes. As Einstein predicted, this collision sent waves through the fabric of space-time, but nearly 100 years passed between Einstein's prediction and the first measurement of these waves by the advanced LIGO detectors. The detection was made possible by many advances in the precision measurement. I will describe the detectors and one of the key technologies, the vibration isolation for the optics; at 10 Hz, the motion of the LIGO mirrors is at least 1,000,000,000 times less than the motion of the ground. By creating one of the quietest places on Earth, we have created a new way to "listen" to the stars.
Continuous scan beamforming using a rotating microphone array for mapping of acoustic sources in a soundproof chamber
Authors: Lee Abe H. , White Andrew , Shah Parthiv
Published: April 2019

Continuous scan beamforming (CSBF) is a novel approach that can improve the dynamic range of a microphone array used for source localization. In the conventional beamforming approach in which spatially fixed sensors are used, the number of sensors employed determines the dynamic range of the array. Whereas, in the CSBF approach, by employing moving sensors in a prescribed motion, the effective number of sensors (so-called virtual sensors) used for the beamforming process can be greatly increased, and therefore, it can provide enhanced dynamic ranges close to the theoretical limit. In the CSBF process, for reconstruction of the time data acquired by moving sensors, stationary microphones are used for phase referencing. At ATA Engineering, Inc., a rotating, planar configuration array of 60 microphones was built and tested in a soundproof chamber with spatially distributed acoustic sources inside. The results showed that CSBF has much better performance than the conventional beamforming that employs fixed sensors; CSBF is able to discriminate tested sources that are almost 20 dB apart, which is not possible with the conventional approach. Due to the enhanced dynamic range, CSBF provides much cleaner mapping of the distribution of sources without physically increasing the number of sensors.
Variations of acoustic noise intensity accompanying internal wave solitons
Authors: Katsnelson Boris , Godin Oleg A. , Zhang Qianchu
Published: April 2019

In this paper, acoustical noise intensity fluctuations recorded by single hydrophones (SHRUs) in the Shallow Water 2006 experiment are studied. The area of experiment (New Jersey Atlantic shelf) is characterized by a remarkable activity of internal waves, in particular, approximately twice per day trains of nonlinear internal waves (NIW) consisting of up to ten separate peaks with the amplitudes about 10–15 m and wave front parallel to the coastal line move toward the beach. During its motion trains of NIW cross positions of five SHRUs, located about 5–8 km to each other along line perpendicular to the coast as well as thermistor’s strings which allow us to estimate the shape and evolution of trains while they are propagating. It is shown that the appearance of irregular wideband sound field (amplitude by up to 20–40 dB greater than noise background) takes place when the train of NIW is passing through the location of the corresponding SHRUs. The nature of these signals is discussed, and the spectrum and specific temporal variations as well as other characteristics are analyzed. [Work was supported by ONRG, NSF, and BSF.]
Variability of the sound field in the presence of internal Kelvin waves in a stratified lake: The Sea of Galilee as a case study
Authors: Uzhansky Ernest , Katsnelson Boris , Lunkov Andrey , Ostrovsky Ilia
Published: April 2019

The spatiotemporal variability of low- and mid-frequency sound field in the presence of internal Kelvin waves (IKWs) was studied in the Sea of Galilee. Experimental measurements of the sound field were carried out using a vertical line array (VLA) consisting of ten hydrophones with 3 m spacing. The VLA was deployed in the deepest (37 m) part of the lake. Signals were transmitted from the source deployed at the peripheral lake location at a distance of 5.5 km from the VLA at 8-m depth. Linear frequency modulation pulses (300–2000 Hz) were transmitted with 5 sec intervals during >24 h (the period of the IKWs). IKWs were registered using three thermistor chains (TCs) positioned along an offshore transect at 10-m, 20-m, and 37-m station depths. This setting allowed us to characterize the variations of the thermal structure and the corresponding sound speed profile along transect. The vertical structure of the sound field registered with the VLA shows connection with temporal variability of IKWs. The modeling of sound propagation was done using a Parabolic Equation (PE) method, taking into account the parameters of bottom and lake bathymetry. The PE results showed close agreement with our experimental measurements. [Work supported by Israel Science Foundation.]
Broadband acoustic propagation in a seagrass meadow throughout a diurnal cycle
Authors: Lee Kevin M. , Ballard Megan S. , Sagers Jason D. , McNeese Andrew R. , Venegas Gabriel R. , Johnson Jay R. , Wilson Preston S. , Rahman Abdullah F.
Published: April 2019

Acoustic propagation in seagrass meadows is sensitive to gas produced by photosynthesis and respiration. In addition to gas volumes within the seagrass, bubbles are introduced into the water as oxygen diffuses through the plant tissue, leading to dispersion, absorption, and scattering of sound. Because the oxygen production cycle is largely driven by sunlight, these acoustical effects have a diurnal dependence. Previous work has examined the use of acoustics as a remote sensing tool for monitoring the seagrass photosynthetic activity (Hermand, 2004). In the present paper, we describe an acoustic propagation experiment conducted in a Thalassia testudinum meadow in the Lower Laguna Madre, a shallow bay on the Texas Gulf of Mexico coast. A spherical omnidirectional source transmitted frequency-modulated chirps (0.1 kHz to 100 kHz) every 10 min for a 24-h period, during which oceanographic probes measured water temperature, salinity, and dissolved oxygen. The received acoustic signals were match-filtered to obtain band-limited impulse responses, enabling identification of various propagation paths within the waveguide. The dependence of the received acoustic amplitude and frequency content on time-of-day, dissolved oxygen, and other environmental parameters will be discussed with the goal of using acoustics to study seagrass photosynthesis and productivity. [Work supported by ARL:UT IR&D and ONR.]
Dynamic optical coherence elastography: Emerging tool for noninvasive quantification of mechanical properties of ocular tissues
Authors: Larin Kirill
Published: April 2019

Optical coherence elastography (OCE) is an emerging method for noninvasive quantification of tissue viscoelastic properties. The underlying technology is based on Optical Coherence Tomography (OCT) imaging and analysis of external (or internal) force-induced mechanical waves propagating through the tissue. In this presentation, I will overview recent progress made in my lab on quantification of mechanical properties of ocular tissues (such as cornea and the lens of the eye) using OCE and their alternations during diseases progression. In particular, I will demonstrate that it is possible to quantify mechanical properties of the cornea and lens as a function of Intra-Ocular Pressure (IOP) and during controlled tissue modifications and treatments, such as corneal cross-linking. These results indicate that OCE is a powerful new technology that can be utilized for the nondestructive biomechanical characterization of ocular tissues in normal and pathological states and could not only assist in basic biomechanical studies but also lead to a new class of optical sensors for diagnosis of diseases. [Work supported, in part, by the U.S. National Institutes of Health (NIH) under Grant Nos. 2R01EY022362 and 1R01HL120140 and U.S. Department of Defense (DOD) Congressionally Directed Medical Research Programs (CDMRP) under Grant No. PR150338.]
Evaluation of posterior sclera viscoelasticity in eyes with papilledema by using ultrasound vibro-elastography
Authors: Chen John J. , Zhou Boran , Kazemi Arash , Sit Arthur J. , Zhang Xiaoming
Published: April 2019

Papilledema is optic nerve swelling caused by increased intracranial pressure, which has the potential to cause significant vision loss. Papilledema is typically bilateral and symmetric but can sometimes be asymmetric and even unilateral. The cause for this asymmetry is unknown. The purpose of this study was to utilize ultrasound vibro-elastography (UVE) to assess for biomechanical differences in eyes with papilledema. Nine patients with papilledema and 9 age-matched controls were enrolled. An external harmonic vibration was used to generate wave propagation through the eyelid with three excitation frequencies of 100, 150, and 200 Hz. A 6.4 MHz ultrasound probe was used to noninvasively measure the wave propagation in the posterior sclera to provide shear wave speeds and viscoelasticity (fit with Voigt model). The magnitudes of the shear wave speed and viscoelasticity of the idiopathic intracranial hypertension patients’ posterior sclera were significantly higher than those of healthy subjects. Moreover, for patients with unilateral papilledema, the magnitudes of wave speed and viscoelasticity of the posterior sclera were statistically higher in eyes with papilledema than in the contralateral eyes without papilledema. UVE provides a noninvasive technique to measure the viscoelastic properties of the posterior sclera, which is stiffer in eyes with papilledema.
Accounting for a wide variety of binaural detection data by combining cross-correlation and signal-detection theory approaches
Authors: Bernstein Leslie R. , Trahiotis Constantine
Published: April 2019

We will discuss several experimental contexts in which a Theory of Signal Detection (TSD) approach to modeling has yielded successful, straightforward, and intuitively appealing accounts of data concerning binaural auditory processing. The primary focus will be on recently published empirical data and quantitative modeling from our laboratory. Those reports demonstrate that data obtained in binaural detection experiments conducted across the last five decades can be accounted for by combining a signal-detection-based decision variable with a cross-correlation-based model of binaural processing that incorporates stages of peripheral auditory processing. Notably, some of the data obtained in those experiments had, therefore, been “problematic” in that they had remained either theoretically unaccounted for or, at best, had been only accounted for via ad hoc approaches. Key to developing the unified account of those experimental results was the calculation and inclusion of the variability of the interaural correlations of the outputs of the model for both masker-alone and signal-plus-masker conditions. We will also discuss recent developments showing how our TSD-inspired approach has proven useful in discovering and explaining why some listeners with slightly elevated, but clinically negligible, audiometric thresholds exhibit reliable and meaningful deficits in binaural performance. [Work supported by Office of Naval Research (N00014-15-1-2140 and N00014-18-1-2473).]
Nonreciprocal metamaterial with programmable nonlinear virtual resistors
Authors: Baz Amr M.
Published: April 2019

Emphasis is placed on the development of a class of active acoustic diodes and metamaterials in an attempt to control the flow and distribution of acoustic energy in acoustic cavities and systems. The proposed active nonreciprocal acoustic metamaterial (ANAM) cell consists of only one-dimensional acoustic cavity provided with active flexible boundaries. These boundaries are made from piezoelectric bimorphs with the inner layers which interact directly with cavity acting as sensors for monitoring the pressures of the propagating acoustic waves. The outer layers of the bimorphs provide the necessary control actions to an array of programmable nonlinear shunted resistors. These resistors are programmable and are designed in such a manner to introduce simultaneous nonlinear damping and cubic hardening stiffness effects. A lumped-parameter model of the ANAM cell is developed to control the nonreciprocal characteristics of the cell by the selection of the proper balance between the nonlinear damping and stiffness effects. Lyapunov stability criterion is used to generate the structure of such a balanced control strategy. The Harmonic Balance Method is used to predict the limit cycle behavior of the ANAM, the backbone characteristics and the stable limits of the control gains. Numerical examples are presented to demonstrate the effectiveness of the proposed ANAM in tuning and programming the directivity, flow, and distribution of acoustic energy propagating though the metamaterial.
Design of broadband active sound isolators based on acoustic bianisotropic metamaterials
Authors: Zhai Yuxin , Popa Bogdan Ioan , Kwon Hyung-Suk
Published: April 2019

The acoustic wave propagation through conventional materials is controlled by two parameters: the mass density and the bulk modulus. It has been shown that two additional parameters called Willis coupling terms are needed in order to describe the dynamics of certain complex media called bianisotropic (Willis) materials. The few bianisotropic (Willis) materials reported so far have experimentally demonstrated the ability of these complex media to control the propagation of sound beyond what is possible with conventional media. For instance, it has been shown that bianisotropic materials could control reflection and transmission coefficients independently and enable high-efficiency sound beam steering devices. In this presentation, we will describe a previously unexplored property of acoustic bianisotropy. Namely, we will present a design of ultra-compact active bianisotropic metamaterials that can serve as excellent sound isolators. In addition, we will discuss the bandwidth and stability of our design. We will show that unlike conventional active sound control devices, active bianisotropic materials are stable even in dynamically changing environments without employing any instability mitigation algorithms.
Building talker knowledge from talker variability
Authors: Xie Xin
Published: April 2019

Listeners reliably extract invariant linguistic category information from speech despite massive cross-talker variability. Existing work shows that talker variability is in part handled by the learning and maintaining of category-specific acoustic distributions towards the statistics in the spoken input from a talker. When do listeners maintain information about talkers’ speech after we meet them, and what kind of information should be maintained in principle? In this talk, I present a computational framework that addresses these questions by linking the statistics of the speech input (production) to predictions about perception. The results provide constraints on the type of inference underlying talker-related adaptivity during speech perception and have direct implications for current research on talker recognition.
Mutual predictability among speech sounds for talker adaptation and recognition
Authors: Chodroff Eleanor , Wilson Colin
Published: April 2019

Processes of talker recognition and adaptation rely on a high degree of inter-talker phonetic variability and systematicity, respectively. While superficially in opposition, talker recognition in part depends on adaptation to the talker at hand. In this talk, we present evidence that talker variability is simultaneously extensive and structured within natural classes of speech sounds. In American English, talker mean peak frequencies for [s] span over 3000 Hz, but the variation in [s] is not independent of that in [z]: strong correlations of the talker mean peak frequency, among other phonetic dimensions, are observed between sibilant fricatives. Covariation among speech sounds indicates mutual predictability, such that evidence from one speech sound could be used to refine estimates or make predictions about a second. Listeners indeed demonstrate perceptual knowledge of covariation in generalized adaptation to novel talkers. After exposure to a talker with a relatively high- or low-peak frequency [z], listeners adjusted their [s]-[ʃ] boundary in accordance with the empirical covariation. As talker recognition entails estimation of a talker’s phonetic parameters, prior perceptual knowledge of covariation could be used to refine estimation of multiple speech sounds from minimal exposure, thus accelerating processes of talker adaptation and recognition.
The acoustical characteristics of a metal ball entering into water
Authors: Shang Dajing , Li Qi
Published: April 2019

The sound of objects into the water is very important to the detection and identification of underwater targets. The Metal ball into the water will produce an unique sound signal, which can be used for monitoring the target and evaluating the performance of the sonar. The main influence terms of the radiation noise of the metal ball into the water are analyzed in this paper, and the noise of the metal ball entering into water consists of initial impact sound and bubble sound, and the characteristics of the initial impact sound and the bubble sound are summarized. A set of metal ball entering the water equipment was set up to make the metal ball enter the water at different depths and angles, and the test was finished in the pool of the Harbin Engineering University Underwater Department. A special acoustic signal during the quiet area is discovered, which is related to the size of metal ball and the speed of the metal ball entering water. The sound of the metal entering water was measured, and the relationship between the sound characteristics of the metal ball entering water and the metal ball size, the velocity, and the angle of metal entering water was obtained by processing the measuring data.
Recording room trends in libraries
Authors: Cuff Nicole
Published: April 2019

The use of libraries in communities and universities continue to evolve to where now there is a trend toward recording rooms in public and university libraries. One such space is a recording suite in a public library intended for the community to use, teens to seniors, with fully amplified bands next to study spaces, with control equipment available for patrons to use. Another in a private university is a podcast suite that overlooks a 4-story glass Atrium, which will be the new central meeting place on campus. The author even personally used recording studio space immediately adjacent to quiet study space at a private university library with their singing group to record an album. Some of the strategies used to make these spaces work together acoustically will be discussed.
Acoustic conditions in two libraries at the University of Nebraska
Authors: Spallino William , Wang Lily M.
Published: April 2019

University libraries serve many roles for students, from group gathering places to quiet study spaces; this makes analyzing and optimizing their acoustics very worthwhile. This paper reviews the acoustics of both main areas and small-group study rooms at the University of Nebraska—Omaha’s Criss Library and the University of Nebraska—Lincoln’s Love Library. Sound level meters were used to log sound levels in the two libraries over multiple days. Those data were then analyzed to understand the libraries’ soundscapes through metrics like average sound levels, statistical sound levels, and occurrence rates of specific sound levels. Impulse responses and transmission loss of partitions were also measured. From those analyses, conclusions are drawn about the acoustic behavior of the libraries and its appropriateness for their purpose.
Considerations for media center design in unconventional environments
Authors: Saunders Melvin
Published: April 2019

The consolidation and simplification of media in production environments has rapidly changed the way that many businesses develop content. Rather than outsourcing media development, many clients have undertaken the task to develop content for both internal and external consumption by building in-house media centers. This paper will focus on some of the lessons learned for these types of projects from both a remediation and new construction process. Acoustical solutions for projects of varying budget and scope including room acoustics, sound isolation, and HVAC noise abatement will also be explored.
Live color encoded speckle imaging platform for real-time complex flow visualization in vivo
Authors: Yiu Billy Y. , Walczak Mateusz , Lewandowski Marcin , Yu Alfred C.
Published: April 2019

Complex flow patterns carry valuable diagnostic information but they cannot be visualized in a time-resolved and intuitive manner in real-time. In this work, we present the first real-time scanning platform for a high frame rate ultrasound technique called color encoded speckle imaging (CESI) and its use in visualizing blood flow dynamics in vivo. CESI visualizes these dynamics through duplex rendering of flow speckle motion and color-coded Doppler velocity estimates. Its live implementation was achieved by integrating a 192-channel programmable ultrasound front-end module, a 5 GB/s capacity data streaming link, and a series of computing kernels implemented on the graphical processing unit (GPU) for beamforming, Doppler processing and display rendering. A slow-motion replay mode was also included to offer coherent visualization of CESI frames acquired at sub-millisecond resolution (0.3 ms). The live CESI scanning platform was found to be effective in facilitating real-time image guidance (>20 fps). In vivo pilot trials also showed that live CESI, when operating in replay mode, can temporally resolve the formation and dissipation of recirculation at the carotid bifurcation and can reveal flow dynamics in the brachial vein during a fist-clenching maneuver. Overall, live CESI has potential for use in routine in vivo investigations that seek to identify complex flow dynamics in real-time and relate these dynamics to vascular pathophysiology.
Spatial analysis of cardiac strain using high-frequency four-dimensional ultrasound in mice
Authors: Damen Frederick W. , Soepriatna Arvin , Goergen Craig J.
Published: April 2019

Cardiac disease remains the number one cause for all mortality in the United States, prompting a continued effort to understand the various factors that exacerbate disease. In this endeavor, mouse models of cardiac disease have served a crucial role by allowing for both investigation of disease factors and longitudinal tracking of cardiac function. Routine assessment of cardiac function in mice can be acquired using high-frequency ultrasound; however, conventional techniques must rely on idealized cardiac geometries to calculate function metrics, as morphometric information is only available from a single plane. Aiming to overcome these limitations, our group has recently developed and validated a high frequency four-dimensional ultrasound (4DUS) technique that provides full volumetric information of the mouse heart synced over one representative cardiac cycle. Analysis of this 4DUS data can provide region-specific wall kinematic information, in contrast to global metrics such as ejection fraction and stroke volume. Preliminary applications of our technique have demonstrated abnormal left-ventricular contractile patterns in mouse models of cardiac hypertrophy, as well as ventricular remodeling in models of myocardial infarction. These initial efforts suggest that widespread adoption of 4DUS has the potential to help increase the amount of information obtained when using mouse models of cardiac disease.
Quantification of murine cardiac hypertrophy using 4D ultrasound
Authors: Berman Alycia G. , Anderson Jennifer L. , Niedert Elizabeth E. , Scott Adrienne , Neu Corey P. , Goergen Craig J.
Published: April 2019

Cardiac hypertrophy is abnormal thickening, followed by dilation, of the heart which can lead to congestive heart failure. Herein, we use a mouse model of hypertrophy to explore the relationship between in vivo strain and the resultant hypertrophic state. To do so, osmotic pumps containing saline (n = 5) or angiotensin II (AngII; n = 10) were surgically implanted into the dorsal flank of C57BL/6J mice. AngII increased blood pressure and cardiac afterload, causing myocardial hypertrophy. Mice were imaged weekly using a VisualSonics Vevo2100 ultrasound system with a MS550D transducer (40 MHz center frequency) to collect ECG-gated Kilohertz Visualization data. In combination with a linear stepper motor, we also collected four dimensional (4D) cardiac data (3D + time). Two weeks post-surgery, pumps were removed from a subset of mice to assess the heart’s ability to repair itself post-insult (n = 5). All mice were euthanized at 4 weeks. Standard metrics of left ventricular mass measured via two-dimensional slices of the 4D data indicated significantly increased mass in the AngII mice by day 14. Removal of the pump enabled significant, but partial, recovery. Current work is being performed to calculate strain within the cardiac wall. Ultimately, we aim to determine if increases in in vivo strain precede increases in cardiac mass.
Advanced beamforming for improved functional assessment in echocardiography
Authors: Byram Brett , Dei Kaz , Schlunk Siegfried , Luchies Adam
Published: April 2019

Echocardiography is one of the most used medical imaging exams. The data from these exams are often used to compute quantitative metrics of cardiac health including measures such as the global longitudinal strain (GLS) or ejection fraction. Metrics related to blood flow are also derived from echocardiography data. These metrics have great potential because ideally, they provide quantitative biomarkers to monitor cardiac function over time and compare patient function to population values. Unfortunately, echocardiography data is often severely corrupted by various forms of acoustic clutter including wavefront aberration, reverberation and off-axis scattering from bright structures like the ribs and lungs. These sources of clutter degrade ultrasound image quality and corrupt the ability to derive reliable quantitative biomarkers of cardiac function. To resolve problems like these, we have been developing non-linear (mathematically) beamformers. These include our aperture domain model image reconstruction (ADMIRE) beamformer and, more recently, our deep neural network beamformer. We have shown that these beamformers are able to reduce errors related to wavefront aberration, reverberation and off-axis scattering, and also that the ADMIRE beamformer can eliminate the underestimation of global longitudinal strain caused by high levels of stationary reverberation caused by the chest wall.
Frequency dependence of the vaporization threshold of sonosensitive perfluorocarbon droplets varying their liquid core and size
Authors: Aliabouzar Mitra , Kumar Krishna , Sarkar Kausik
Published: April 2019

Phase shift liquid perfluorocarbon (PFC) droplets vaporizable by ultrasound have received increasing attention for therapeutic and diagnostic applications. The ultrasound activation pressure required for the phase change of these droplets into echogenic microbubbles is termed acoustic droplet vaporization (ADV). This study systematically investigates the effect of frequency of excitation¾2.25 MHz, 10 MHz and 15 MHz¾on ADV and inertial cavitation (IC) thresholds of a suspension of PFC droplets by varying the physical properties of the liquid droplets (size and boiling point) in a tubeless setup. We prepared lipid-coated droplets with three different liquid cores, perfluoropentane (PFP), perfluorohexane (PFH) and perfluorooctyle bromide (PFOB), of two different size ranges ¾ one with diameter smaller than 3 Î¼m and the other with diameter larger than 10 Î¼m. We found that the ADV threshold increases with frequency for the most volatile PFC liquid, PFP, for both large and small size droplets. While for the small size droplets of higher boiling point liquids, PFH and PFOB, no ADV was detected, for the larger ones ADV threshold decreases with frequency of excitation. ADV thresholds at all the frequencies studied here occurred at lower rarefactional pressures than IC thresholds indicating that phase transition precedes inertial cavitation.
Graduate studies in acoustics and wave physics at Institut d’Acoustique—Graduate School, Le Mans, France
Authors: Tournat Vincent
Published: April 2019

This poster presents the graduate studies in Acoustics at Le Mans (France) offered at the Institut d’Acoustique—Graduate School. Graduate studies in Acoustics at Le Mans University have been awarded in 2018 the excellence label École Universitaire de Recherche among 28 other reference centers for all fields of Science, through a highly selective national call. Master and engineering school programs range from physical acoustics, environmental acoustics, acoustics and vibrations to international masters on electro-acoustics and on wave physics. The education through research is carried out at the LAUM, UMR CNRS, one of the largest acoustics laboratory in the world. Several details, objectives and contact informations on the graduates studies will be given on the poster.
Graduate training opportunities in the hearing sciences at the University of Louisville
Authors: Morgan Shae D. , AlMakadma Hammam , Kondaurova Maria V. , Stilp Christian , Zahorik Pavel
Published: April 2019

The University of Louisville currently offers two branches of training opportunities for students interested in pursuing graduate training in the hearing sciences: A Ph.D. degree in experimental psychology with concentration in hearing science, and a clinical doctorate in audiology (Au.D.). The Ph.D. degree program offers mentored research training in areas such as psychoacoustics, speech perception, spatial hearing, and multisensory perception, and guarantees students four years of funding (tuition plus stipend). The Au.D. program is a 4-year program designed to provide students with the academic and clinical background necessary to enter audiologic practice. Both programs are affiliated with the Heuser Hearing Institute, which, along with the University of Louisville, provides laboratory facilities and clinical populations for both research and training. An accelerated Au.D./Ph.D. training program that integrates key components of both programs for training of students interested in clinically-based research is under development. Additional information is available at http://louisville.edu/medicine/degrees/audiology and http://louisville.edu/psychology/graduate/vision-hearing.
Graduate acoustics education in the Cockrell School of Engineering at The University of Texas at Austin
Authors: Haberman Michael R. , Hamilton Mark F. , Wilson Preston S. , Hall Neal A. , Isakson Marcia J.
Published: April 2019

While graduate study in acoustics takes place in several colleges and schools at The University of Texas at Austin (UT Austin), including Communication, Fine Arts, Geosciences, and Natural Sciences, this poster focuses on the acoustics program in the Cockrell School of Engineering. The core of this program resides in the Walker Department of Mechanical Engineering (ME) and the Department of Electrical and Computer Engineering (ECE). Acoustics faculty in each department supervise graduate students in both departments. One undergraduate and eight graduate acoustics courses are cross-listed in ME and ECE. Instructors for these courses include staff at Applied Research Laboratories at UT Austin, where many of the graduate students have research assistantships. The undergraduate course, taught every fall, begins with basic physical acoustics and proceeds to draw examples from different areas of engineering acoustics. Three of the graduate courses are taught every year: a two-course sequence on physical acoustics, and a transducers course. The remaining five graduate acoustics courses, taught in alternate years, are on nonlinear acoustics, underwater acoustics, ultrasonics, architectural acoustics, and wave phenomena. An acoustics seminar is held most Fridays during the long semesters, averaging over ten per semester since 1984. The ME and ECE departments both offer Ph.D. qualifying exams in acoustics.
Graduate education and research in architectural acoustics at Rensselaer Polytechnic Institute
Authors: Xiang Ning , Braasch Jonas , Brooks Todd
Published: April 2019

The Graduate Program in Architectural Acoustics has been constantly advanced from its inception in 1998 with an ambitious mission of educating future experts and leaders in architectural acoustics, due to the rapid pace of change in the fields of architectural-, physical-, and psycho-acoustics. Recent years the program’s pedagogy using science, technology, engineering, and mathematics methods (STEM) has been proven to be effective and productive, including intensive, integrative hands-on experimental components that integrate architectural acoustics theory and practice. The graduate program has recruited graduate students from a variety of disciplines including individuals with B.S., B.Arch., or B.A. degrees in Engineering, Physics, Mathematics, Architecture, Electronic Media, Sound Recording, Music and related fields. Under this pedagogy and research environment graduate students have been succeed in the rapidly changing field. RPI’s Graduate Program in Architectural Acoustics has since graduated more than 150 graduates with both M.S. and Ph.D. degrees. Under the guidance of the faculty members they have also actively contributed to the program’s research in architectural acoustics, noise control, psychoaoustics, signal processing in acoustics as well as our scientific exploration at the intersection of cutting edge research and traditional architecture / music culture. This paper illuminates the evolution and growth of the graduate program.
The effect of axial vibrations on the input impedance of the trumpet
Authors: Rodgers Brooke , Moore Thomas
Published: April 2019

It has been shown that the vibrations in the bell section of the trumpet can influence the sound produced by the instrument. Recent research has indicated that these effects may be traced the axial vibrations of the bell. We report experimental results that relate the input impedance of the trumpet to the phase of externally induced longitudinal motion. These results indicate that the phase difference between the driver and the bell motion can significantly affect the input impedance. [Work supported by NSF Grant #PHY-160749.]
Binaural measurement and psychoacoustic analysis—An advantage for the environmental noise research
Authors: Genuit Klaus
Published: April 2019

The new ISO TS 12913-2 “Data collection and reporting requirements” describes a lot of new aspects how to analyze soundscape (e.g., environmental noise) and provides new tools for the measurement and analysis. Whereas the use of binaural recording and psychoacoustic analysis is well known in the field of product sound quality especially with respect to the automotive field, the application of these tools within the soundscape analysis is new. This paper illustrates based on different examples given from the field of environmental noise the superiority and advantage of these tools in comparison to the conventional measurement using an omnidirectional microphone calculating the A-weighted sound pressure level.
An experimental soundscape study, combining binaural recordings, in situ questionnaires and behavioral mapping
Authors: Radicchi Antonella
Published: April 2019

In 2014 and, more recently, in 2018 the ISO norms on soundscape were released with the aim of providing a conceptual framework and standardized data collection methods for the international community of scientists and professionals with an interest on soundscape. This paper presents a research study conducted in the summer of 2018 in a Berlin public square where, following the ISO norms on soundscape, methods were applied to further investigate the findings of the “Beyond the Noise: Open Source Soundscapes” project, i.e., the everyday quiet areas as identified by the participants in the project. First, the paper introduces the research questions originated from the previous study. Second, it outlines the fieldwork procedure and methods, consisting in binaural measurements made in parallel to in situ questionnaires and behavioral mapping. Third, it discusses the initial results and limitations of the study. In conclusion it argues the soundscape approach potential within urban design and planning, illustrating how the results were partially exploited to design a bottom-up master plan proposal so as to improve the public square’s soundscape and reduce noise pollution.
Flat acoustics with soft gradient-index metasurfaces
Authors: Mondain-Monval Olivier , Kumar Raj , Brunet Thomas , Jin Yabin , Poncelet Olivier
Published: April 2019

There is an important demand for the manufacture of materials allowing a precise control of the propagation of acoustic waves. This depends, among other things, on the speed of propagation of the waves in the material, which is expressed by the so-called acoustic index: n = C L,ref / C L,mat where C L,ref and C L,mat are the propagation velocities of acoustic waves in a reference medium (water for us) and in the material, respectively. We have recently shown that silicone-based porous polymer materials possess exceptionally high and scalable propagation indices, which can be tuned by a precise control of the polymer's mechanical properties and porosity [1]. Our materials are obtained using an emulsion templating method coupled with a drying process that will be described in my presentation. Using this experimental approach, we were able to produce materials with an acoustic index gradient allowing, among other things, the development of a flat acoustic lens [2]. I will present the synthesis and the characterization of these materials as well as their acoustic properties. [1] A. Kovalenko, M. Fauquignon, T. Brunet, and O. Mondain-Monval, “Tuning the sound speed in macroporous polymers with hard or soft matrix,” Soft Matter 13, 4526–4532 (2017). [2] Y. Jin, R. Kumar, O. Poncelet, O. Mondain-Monval, and T. Brunet, “Flat acoustics with soft gradient-index metasurfaces”, Nat. Commun. (to be published).
Acoustic correlates of hypokinetic articulation of continuously spoken sentences
Authors: Biswas Amitava , Schaub Mary , Cloud Steven
Published: April 2019

Hypokinetic speech involves reduced range of motion of the articulators such as tongue, lips, and jaw. As a result, the formant transitions are relatively reduced. This characteristic may be observed in some adults and children. An algorithm has been developed to estimate the relative variations in formant transitions in continuously spoken sentences. Its sensitivity, specificity, and applications in clinics will be discussed.
Vowel space and variability in infant- and adult-directed speech
Authors: Burkinshaw Kelly D. , Holt Lori L. , Curtin Suzanne
Published: April 2019

Infant- and adult-directed speech are acoustically-distinct registers, but whether the characteristics of infant-directed speech (IDS) promote speech category learning is unclear. Several studies have reported an expanded vowel space in IDS compared to ADS; point vowels (/i/, /a/, /u/) are, on average, more distinct from each other in IDS. But, other studies report greater intra-category variability which might diminish any benefits of an expanded vowel space. Here, we examined vowel productions across five vowels as mothers spoke to their infants (7- or 15-months) in IDS and an adult experimenter in ADS. We observed an expanded point vowel space and an increase in variability of within-category vowel productions in IDS toward 15-month-olds, compared to ADS. Thus, although the centroids of the point vowels were more separated in IDS toward 15-month-olds than ADS, production variability led to substantial category overlap. Yet, classification modeled using Discriminant Function Analysis (DFA) revealed near-ceiling classification rates for both registers, indicating that there was no classification advantage of the increased distance among IDS point vowels. We found neither vowel space expansion nor increased variability in IDS toward 7-month-olds. These findings inform how distributional characteristics of speech input may contribute to vowel category learning in infancy.
Simulations of collar waves for acoustic logging while drilling in the frequency and the spatial domains
Authors: He Xiao , Ji Yunjia , Chen Hao , Wang Xiuming
Published: April 2019

Tool waves generated by the presence of the drill collar can cover the formation signals we need. The suppression for those collar waves has been a challenge for designing acoustic logging while drilling (ALWD) tools. To study the collar wave characteristics, we evaluate the excitation intensity of the modes with varying frequencies and positions by solving the elastic wave equations. Analysis results show that the collar wave energy concentrates in the cylindrical tool model. And the radial location of its peak gradually moves from the inner surface to the outer wall with the increasing frequency. The particle vibration trajectories contributed by the collar wave are also investigated. It is revealed that the collar mode in the lower frequency range has an approximately longitudinal polarization, while it tends to the transverse-wave-like motion at high frequencies. According to these features, we propose strategies on the tool structure designs to suppress the collar waves in the lower- and the higher- frequency ranges, respectively. Numerical examples further validate that the proposed collar structures with interlayers or grooves can well attenuate the collar wave propagation.
Determining fracture properties from acoustic borehole waves: theory and experimental results
Authors: Fan Huajun , Smeulders David
Published: April 2019

A borehole in the subsurface may penetrate rocks which are porous, permeable and fractured. Pressure transients in the borehole will therefore cause viscous fluid to flow into and out of the wall of the borehole. This forced flow consumes some energy and affects the phase velocity and amplitude of the waves traveling in the borehole fluid column. These effects can be evaluated to extract information about the rocks adjacent to the borehole, which is of paramount importance for the oil and gas industry. This work discusses laboratory wave experiments in a 7.5 m long vertical shock tube. Rock samples having a vertical borehole and horizontal fractures are installed in the shock tube and filled with water. The shock tube generates broadband pressure transients in the borehole. These are measured in the borehole at variable depth by means of a sliding pressure probe. Repetitive experiments are combined into borehole microseismograms. In this way borehole wave reflection and transmission coefficients over the fractures are determined. The results show good agreement with low-frequency theory, where it is assumed that the wavelengths are much larger than the tube diameter. Inversely, it is shown that the aperture and the length of the fracture can directly be inferred from acoustic borehole experiments.
Assessing organic richness of source rocks through integration of acoustic logs and microresistivity images
Authors: McQuown M. S.
Published: April 2019

Accurate evaluation of source rock thickness and organic richness are key components to estimating the hydrocarbon potential of a basin and identifying target zones in self-sourcing shale plays. The millimeter-scale variability in mineralogy and organic matter concentrations in source rocks can make petrophysical quantification problematic when relying on the resolution of standard well logs. Integrating acoustic well log data with microresistivity images with can improve resolution while generating more meaningful information than their separate results. We developed a new algorithm that utilizes the superior resolution and circumferential coverage of microresistivity images and integrates them with enhanced acoustic data to assess the organic richness of source rocks. The result is an oriented 360 deg pseudo-sonic image that reveals anomalous properties related to organic richness. The validity of the method is assessed by comparing the results with standard well log-derived solutions for total organic carbon. Excellent correlation between the image results and petrophysical solutions is observed.
A method to locate acoustic emission events induced by hydraulic fracturing using waveform correlation weighted by amplitude stacking
Authors: Zhang Chengwei , Qiao Wenxiao , Chen Xiaohua
Published: April 2019

Acoustic emission monitoring has been the best technique to evaluate hydraulic fracturing which is the most common method used to induce fractures for stimulating hydrocarbon reservoirs. Correlation-based and amplitude-stacking-based methods, both are based on migration and are all suitable for locating acoustic emission events induced by hydraulic fracturing without the need to pick the arrival times of the P- and S-waves. By comparing and analyzing the advantages and disadvantages of the two location methods, we propose a new weighted correlation method using both amplitude and waveform correlation. First, we calculate the travel time of acoustic waves from the trial point in the formation to each receiver by the ray-tracing method, and further to determine the time-window positions of the P- and S-waves on all waveforms. Then, we calculate the correlation of the waveforms in the windows and the amplitude stacking of the average energy ratio between the short-time window and the long-time window on the original acoustic waveforms. Finally, we use the correlation weighted by amplitude stacking to image space locations of acoustic emissions. Tests with synthetic data show that the weighted correlation method has stronger stability and lower location uncertainty than the existing migration-based location methods.