bluuebunny/crossref_metadata_2025 huggingface dataset:
Broadband classification and statistics of long-range, mid-frequency sonar measurements of aggregations of fish
Authors: Jones Benjamin , Stanton Timothy K. , Colosi John A. , Gauss Roger C. , Fialkowski Joseph M. , Jech J. M.
Published: May 2014

Scattering from fish can constitute a significant portion of the high-amplitude echoes in the case of a horizontal-looking sonar system operating at mid-frequencies (1–10 kHz). In littoral environments, reverberation from fish with resonant gas-filled swimbladders can dominate bottom and surface reverberation and add spatio-temporal variability to an already complex acoustic record. Measurements of sparsely distributed, spatially compact fish aggregations have been conducted in the Gulf of Maine using a long-range, broadband sonar with continuous coverage over the frequency band of 1.5–5 kHz. Concurrent downward-looking, multi-frequency echosounder measurements (18, 38, and 120 kHz), and net samples of fish are used in conjunction with physics-based acoustic models to classify and statistically characterize the long-range fish echoes. A significant number of echoes, which are at least 15 dB above background levels, were observed in the long-range data and classified as due to mixed assemblages of swimbladder-bearing fish. These aggregations of fish produce highly non-Rayleigh distributions of echo magnitudes. The probability density functions of the echoes are accurately predicted by a computationally efficient, physics-based model that accounts for beam-pattern and waveguide effects as well as the scattering response of aggregations of fish. [Work supported by the U.S. Office of Naval Research.]
Quantitative three dimensional nonlinear inverse scattering and reflection breast imaging: Initial clinical results
Authors: Wiskin James , Borup David , Iuanow Elaine , Klock John , Lenox Mark
Published: May 2014

Water bath breast scanners utilize either ray based or inverse scattering techniques for the quantitative images. The 3D inverse scattering approach we use requires a 3D forward and back-propagation problem to be solved, resulting in ~1.2 mm resolution images. The resulting speed of sound map is then used in a 3D inhomogeneous, eikonal equation based reflection algorithm to account for refraction effects, and yield a 3D co-registered speckle free 360 degree compounded B-scan like volume. There is no harmful ionizing radiation, no compression, and no required contrast agents for proper utilization of our device. The quantitative transmission ultrasound (QTUS) images are independent of operator skill. The patient lies prone on a full length table with the breast pendant in the water bath. The breast is gently immobilized with the use of a breast retention pad that magnetically “attaches” to a magnetic retention rod for imaging of the breast. Scan time for each breast is approximately 10 min. We will show full 3D quantitative images obtained from consented, anonymous patients from several academic collaborating institutions. We will compare our QTUS images with mammographic, MRI, and hand held US images, and correlate biopsy results where appropriate.
Using Python to teach mathematics, physics, and acoustics
Authors: Thomas Derek C. , Christensen Benjamin Y.
Published: May 2014

Advanced technical courses often suffer from a lack of interactive materials. Common tools to remedy this deficiency include MATLAB and Mathematica, both of which can be prohibitively expensive to obtain outside of the university environment. Python is a scripted language that is easy to read and use and is rapidly emerging as a lingua franca for scientific computing due to the flexibility and facility of the language, the large and active community, and the large number of high quality scientific libraries that are available in Python. Python provides a free and open source tool to develop classroom materials that students can modify and extend. We discuss the use of Python in teaching advanced topics in mathematics, physics, and acoustics. Examples are drawn from courses in acoustics, mechanics, and mathematical and computational physics
Research on the measurement and application of surface diffusivity—Takes Concert Hall at Gulangyu Music School in Xiamen as an example
Authors: Shuai Lu W. , Xue Xiaoyan , Wang Peng , Yan Xiang
Published: May 2014

The surface diffusivity is an important acoustical attribute of material, which is highly correlated with the sound quality of a concert hall. This paper introduces the theory and practical method to measure the surface diffusivity in laboratory, which is more precise and objective than traditional Surface Diffusivity Index (SDI), and then takes the design of the concert hall at Gulangyu Music School in Xiamen as an example, shows the diffusivity features of its six-sided-cylinder shaped GRG ceiling material, demonstrates the design method and significance of using diffusive material in room acoustic design.
The use of sport centers for musical shows
Authors: Trematerra Amelia , Iannace Gino
Published: May 2014

The sport centers are often used for musical shows, these buildings are built for sporting events, and they have a large volume with surfaces acoustically reflective (concrete steps, plaster and concrete ceilings) and have high values of reverberation time. In this work, a study of sporting center “Pala Jacazzi” in Aversa (Italy) for musical shows is reported. This building was designed for sport such as basketball and volley, has a volume of 28.000 cubic meters, length is 60 m, width is 60 m, and the seating capacity is 2.000. The acoustic measurements were carried out in accordance with ISO 3382, with an omnidirectional sound source, feed with a MLS signal, put in the game rectangle, and the measurements microphone put in different point on the steps. The average value, without audience, of T30 at 1.0 kHz is over 5.0 s; this is an high value if the sporting center must be used for musical shows. The software for the architectural acoustic “Odeon” is used to choose the type of absorbent material to insert and to evaluate the area of the walls and ceiling to cover for reduce T30 values, without audience, to 3.0 s.
Mixing console design for telematic applications in live performance and remote recording
Authors: Samson David J. , Braasch Jonas
Published: May 2014

The purpose of this presentation is to introduce a hardware-based mixing console architecture for telematic applications that integrates key features germane to distributed performance and remote recording. The current practice in state of the art telematic performance uses simple software-based interconnection with complex routing schemes and offers minimal flexibility or control over key parameters necessary to achieve a professional workflow. In addition to all customary features, the console will have surround panning capability for both the motorized binaural manikin as well as all sources within the auralization module. Key features such as self-labeling channel strips, onboard latency monitoring, synchronized remote audio recording and monitoring, and a highly flexible routing architecture will be integrated into the console design. This console design will provide a platform for the audio engineer to realize the full potential of telematics for networked performance and remote recording.
Change detection in complex acoustic scenes
Authors: Chait Maria
Published: May 2014

The notion that sensitivity to temporal regularity (TR) plays a pivotal role in auditory scene analysis (ASA) has recently garnered considerable attention. Nevertheless, evidence supporting a primary role for TR is based on experiments employing simple stimuli consisting of one, or two, concurrent sound sequences. Whether the role of TR in mediating ASA is robust to more complex listening environments is unknown. The present study investigates sensitivity to TR in the context of a change detection task, employing complex acoustic scenes comprised of up to 14 concurrent auditory objects. Sequences of sounds produced by each object were either temporally regular (REG) or irregular (RAND). Listeners had to detect occasional changes (appearances or disappearances of an object) within these “soundscapes.” Listeners' performance depended on the TR of both the changing object and the scene context (TR of other objects in the scene) such that RAND contexts were associated with slower response times and substantially reduced detection performance. Therefore, even in complex scenes, sensitivity to TR is critical to our ability to analyze and detect changes in a dynamic soundscape. Importantly, the data reveal that listeners are able to acquire the temporal patterning associated with at least 14 concurrently presented objects.
Performance-based and subjective measures of perceptual organization in humans
Authors: Oxenham Andrew J.
Published: May 2014

Measures of auditory perceptual organization in humans have traditionally relied on subjective reports from subjects. For instance, in alternating tone sequences, subjects might be asked to report whether they hear one or two streams. In order to investigate perceptual organization in non-human species, it can be useful to devise tests that are more objective, in that they have a right and a wrong answer and do not rely on introspection. Recent studies from our laboratory have employed various objective and subjective tasks to provide converging evidence in the search for the underlying principles of auditory perceptual organization. It is suggested that different tasks can bias potentially multi-stable percepts in one way or another, which in turn may be useful in uncovering neural correlates of perceptual organization that can vary even when the acoustic stimuli remain the same. [Work supported by NIH grant R01DC007657.]
Cortical processes for navigating complex acoustic environments
Authors: Shamma Shihab
Published: May 2014

Humans and other animals can attend to one of multiple sounds and follow it selectively over time. The neural underpinnings of this perceptual feat are the object of extensive investigations. In this talk, it is argued that source segregation depends primarily on temporal coherence between responses that encode various features of a sound source. An algorithm for implementing this process will be discussed, especially the components that are inspired by adaptive auditory cortical mechanisms. The postulated necessary role of attention in this process will be addressed, and in particular how it leads to binding of all temporally coherent features of a source (e.g., timbre and location) to segregate them from the incoherent features of other sources.
Manatee hearing and sound localization can help navigate noisy shallow waters and cocktail events, no Lombard's needed
Authors: Gerstein Edmund R. , Gerstein Laura
Published: May 2014

Simultaneous masking procedures were used to measure the hearing and underwater sound localization abilities of West Indian manatees. Auditory detection thresholds of pulsed, no-pulsed pure tones, and complex sounds were measured against white noise using forced-choice paradigms. Auditory thresholds as a function of intensity, center frequency, bandwidth, pulse rate, and spectral characteristics were measured. Resulting critical ratios for pure tone measurements demonstrated manatees have acute frequency filtering abilities compared with humans and other marine mammals. Signal repetition rate along with amplitude and frequency modulation providing temporal contrasts against aperiodic background noise and lowered detection thresholds. FM signal detection thresholds were measured at or below ambient background levels. Results with species specific calls and boat noise suggested loudness summation across distant critical bands, as well as FM and amplitude modulation reduced the masking effects observed with pure tones. Manatees are well adapted for hearing and locating high frequency sounds in noisy shallow water habitats where physical boundary and near surface phenomena impede the propagation of low frequencies. Narrow critical bands and selective perception of pulsed signals may be adaptations for detecting and locating species-specific vocalizations. High frequency harmonics in manatee calls provide essential directional cues between mothers and calves.
Investigating the temporal dynamics of dolphin biosonar using phantom echoes and auditory evoked potentials
Authors: Finneran James J. , Mulsow Jason , Houser Dorian S.
Published: May 2014

Phantom echo generation replaces physical targets with electronic signals that can be delayed in time, scaled in amplitude, and broadcast to an echolocating animal to simulate echoes from distant objects. Compared to physical targets, phantom echoes have the advantages of allowing for instantaneous changes in target characteristics, independent manipulation of echo delay and echo amplitude, and easy randomization of target range. At the Navy Marine Mammal Program in San Diego, California, phantom echo generation is combined with measurements of auditory evoked potentials to investigate the temporal dynamics of biosonar signal emission and reception in bottlenose dolphins. The studies are primarily focused on examining automatic gain control mechanisms by measuring changes in hearing sensitivity — assessed via the auditory steady-state response (ASSR) to an amplitude modulated tone — over time courses corresponding to single biosonar click-echo pairs. Results show the ASSR amplitude initially decreases at the time of click emission and then recovers following click emission, with the time course of recovery related to target range, click amplitude, and tone frequency. Additional studies are focused on dynamic changes in click emissions that occur with changes in target range. [Work funded by SSC Pacific Naval Innovative Science and Engineering (NISE) program.]
Mechanisms of distance-invariant recognition of target strength in the biosonar of odontocetes
Authors: Supin Alexander , Nachtigall Paul
Published: May 2014

Invariant target recognition by sonar requires assessment of the target strength invariably of distance despite wide variation of the echo level. Information on the echo delay and the level of the emitted pulse allows computing of the target strength. The question is: which particular mechanisms perform this computation in the biosonar of odontocetes? Investigations of the auditory evoked potentials (AEPs) during echolocation in several odontocetes have shown that comparison of the emitted pulse level, echo delay, and echo level is based on the forward masking of the echo-response by the preceding self-heard emitted click. Prolongation of the echo delay results in releasing of the echo-related AEP from masking. This release from masking compensated for the echo attenuation with distance. As a result, the echo-related AEP amplitude depended on the target strength and little depended on the target distance. Moreover, the forward-masking duration depended on the level of the emitted pulse. As a result, the echo-related AEP featured amplitude little depended on the level of the emitted pulse. The constancy of the echo-related AEP amplitude indicates the dependence of sensation level of the echo only on the target strength and the independence of both emitted click level and target distance.
Encoding phase information is critical for high resolution spatial imaging in biosonar
Authors: Gaudette Jason E. , Simmons James A.
Published: May 2014

The auditory system is responsible for translating acoustic information into a robust neural representation. In echolocating mammals, precise timing of neural onset-responses is critical to reconstruct complex acoustic scenes. Phase is often ignored in transmit and receive beam patterns, but it holds significance when considering broadband signals. A beam pattern's phase alternates outside of the main lobe, which leads to a frequency-dependent structure that is useful for spatial localization. For imaging in azimuth, binaural spectral patterns and time delay between the ears encode angular position. Imaging in elevation relies principally on specific spectral patterns encoded by each ear. The additional phase information decorrelates broadband echoes arriving from off-axis. This decorrelation only occurs on the order of a single wave period; however, the pattern of dispersion across frequency is sufficient to defocus echoes arriving from off-axis in the peripheral region, while accepting echoes arriving from the focal area of attention. We propose that acoustic spectral pattern matching by echolocating animals includes both magnitude and phase components of beams in the form of timing the onset response. Computational modeling results are presented showing how encoding phase information leads to high-resolution images despite dynamic environments and variability in the target strength of objects.
Reconstructing the acoustic scenes encountered by free-flying, foraging bats
Authors: Lee Wu-Jung , Sändig Sonja , Denzinger Annette , Schnitzler Hans-Ulrich , Horiuchi Timothy K. , Moss Cynthia F.
Published: May 2014

Aerial insectivorous bats face the challenge of efficient echo scene analysis for localizing obstacles and capturing prey in flight. Data collected with a telemetry microphone mounted on the foraging bat's head provide a valuable opportunity to reconstruct acoustic scenes comprised of echoes returning to the bat's ears. This study explores the information embedded in echoes from a tethered insect and background clutter recorded by the telemetry microphone in laboratory experiments. Using images from high-speed video cameras and recordings from a far-field microphone array, angular information about different objects in the echoes are restored by assimilating the reconstructed bat's position and echolocation beam aim with respect to the objects along its flight trajectory toward prey capture. This procedure is further augmented by theoretical simulations using acoustic scattering principles to circumvent the limitation imposed by the sensitivity and signal-to-noise ratio of the telemetry microphone. The reconstructed acoustic scenes offer an avenue for detailed analysis of important cues for figure-ground separation in a cluttered environment, and serve as a basis for subsequent neurocomputational modeling of auditory scene analysis performed by the bat's sonar receiver.
Acoustic scattering characteristics of pelagic and coastal nekton
Authors: Warren Joseph , Becker Kaylyn , Chu Dezhang , Benoit-Bird Kelly
Published: May 2014

Measurements of several acoustic scattering characteristics were made for a variety of different nekton. At-sea broadband high-frequency (100s to 1000s kHz) backscatter measurements were made on several species of myctophids and other types of pelagic nekton (e.g. fish, shrimp). Animals were caught in mid-water trawls off the coast of Oregon during the summer of 2012, and measurements were made on fresh specimens from multiple species. Both broadside (dorsal) and end-on (head/tail) measurements were recorded. There was strong variability among and within species as well as with animal orientation. We also report measurements of swim-bladder size, shape, and fullness for the pelagic myctophids. Additionally, high-resolution computerized tomography (CT) scans were made for several coastal nekton (including squid, silverside, and sea bass) species from New York. These scans provide information on the density contrast of the various organs and other structures in the animal. These data provide useful information for acoustic scattering models of these and other similar animals.
Modeling the acoustic color of large aggregations of fish
Authors: Burnett David
Published: May 2014

The Naval Surface Warfare Center Panama City Division has developed a 3-D finite-element computer simulation system, PC-ACOLOR, for modeling the “acoustic color” (target strength as a function of frequency and aspect angle) of realistic elastic objects, either singly or in aggregations, that are near the bottom of the ocean or in deep water. It employs 3-D continuum mechanics throughout the entire computational domain. All objects and fluids are treated collectively as a single heterogeneous continuum; no engineering approximations are used anywhere. PC-ACOLOR was developed originally for modeling manmade structures, but it is intrinsic to finite-element modeling that the same code can be applied, unaltered, to any elastic objects, whether they be manmade structures or biological organisms. The talk will give an overview of PC-ACOLOR: structural acoustic concepts; modeling techniques; verification and validation; and examples of different types of objects that have been modeled, including aggregations of many fish.
Target phase information for acoustic target identification: Method and preliminary results
Authors: Islas-Cital Alan , Picó Rubén , Atkins Phil
Published: May 2014

Target phase information in acoustic backscattering has been proposed as an additional target identification parameter. In general, incorporating phase into sonar signal processing for acoustical oceanography could aid in the assessment of fish populations and ecosystems. In this work, a broadband sonar system calibrated in amplitude and phase is used to measure the response of submerged targets in a laboratory water tank. Frequency domain data processing is applied, with target phase measured as a phase angle difference between two frequency components. This approach aims to eliminate range factors, leaving only target-induced phase features. The method is developed and validated by comparing experimental results to analytical and numerical methods, in the characterization of some targets with regular geometries such as spheres, shells, and cylinders. A compensation algorithm is implemented to account for phase ambiguities and arrive to a figure of merit for template classification. Simplified scenarios are studied in order to demonstrate the potential applicability of this method.
Comparison of near-field acoustic coherent backscattering simulations with optics theory and experiments
Authors: Mookerjee Adaleena , Dowling David R.
Published: May 2014

Remote discrimination of fish schools from other scatterers in the water column is important for environmental awareness and monitoring, and for a variety of sonar applications. Depending on the school's geometry and number of fish, and the fish's scattering characteristics, there may be preferential backscatter of sound, a phenomenon known as coherent backscatter enhancement (CBE). Thus, the presence and characteristics of CBE could help in discriminating fish schools from other objects. For CBE, the addition of in-phase scattered waves from the propagation path pairs yields a scattered intensity enhancement of a factor of two in the direction opposite to that of the incident wave. However, prior simulations based on the Foldy (1945) equations have suggested the enhancement may be greater than a factor of two for relatively large closely spaced scatterers. This presentation re-examines this topic and provides new CBE simulation results for near field scattering from finite-sized aggregations of point scatterers. Comparisons are made with equivalent results from the optics experiments of Wolf and Maret (1985) and the theory of Akkermans et al. (1986). Extension of this effort to comparisons of CBE from single frequency and broadband pulse illumination is anticipated. [Sponsored by the Office of Naval Research.]
Extracting effective medium properties for fish schools from resonator and free-field measurements
Authors: Dolder Craig N. , Enenstein Gregory R. , Lee Kevin M. , Wilson Preston S.
Published: May 2014

Resonator and free-field measurements were performed with both real and model fish schools in order to determine the relationship between fish school density and sound speed and absorption of acoustic waves. The results are compared to effective medium models for sound propagation through fish and encapsulated bubbles. The current species under study is Danio rerio (zebrafish); however, this technique can be extended to other fish species. [Work supported by ONR.]
Exploration of a Bloch wave expansion technique for analyzing backscattering from large fish schools
Authors: Kulpe Jason A. , Leamy Michael J. , Sabra Karim G.
Published: May 2014

Scattering from large fish schools at typical SONAR frequencies (1–10 kHz) can significantly contribute to volume reverberation. An efficient modeling technique, which accounts for fish' spatial configuration and inter-fish multiple scattering effects, is sought to quantify the acoustic scattering from a large fish school. Recent work has exploited the near-periodic nature of the schooling fish to represent the school as an equivalent phononic crystal (PC) composed of air-filled swim bladders periodically arrayed in a water matrix. Using the Bloch theorem applied to infinite media discretized by finite elements, the approach is capable of quickly and accurately generating the band structure and reflection/transmission coefficients for an incident plane wave. In this work, we extend the analysis approach to finite-sized fish schools to quantify the backscattering as a function of incident wave frequency, school geometry, and weak internal disorder. Scattered field predictions are compared against a self-consistent scattering method as well as full-field finite element simulations. For the presented approach, we note fast and scalable computation (with respect to frequency and school size) with very good agreement in predicted scattered pressure fields and the frequencies corresponding to peak target strengths. This work shows promise for predictive SONAR modeling.
A practical, robust approach to high resolution ultrasonic breast tomography
Authors: Huthwaite Peter , Simonetti Francesco
Published: May 2014

Breast ultrasound tomography is considered a potentially safer, more reliable, and more sensitive alternative to the widely used mammography for breast cancer diagnosis and screening. Vital to achieving this potential is the development of imaging algorithms to unravel the complex anatomy of the breast. Bent Ray Tomography (BRT) is the most prominent algorithm, producing sound-speed maps, but the underlying approximation of ray theory means that the algorithm is unsuitable for structures where significant diffraction is present. Accordingly, the maximum resolution of the BRT algorithm is not sufficient to image the details of the breast on the scale of a few millimeters. Therefore, iterative full-wave inversion techniques are often applied to improve the resolution of the BRT image, but they are typically slow or fail because of the uncertainties such as 3D effects, noise, or transducer characteristics. Presented here is a solution where the BRT algorithm is combined with diffraction tomography (DT), avoiding iterations yet producing a high resolution sound-speed image. It is demonstrated with both numerical and experimental data how this can successfully—and robustly—deal with a range of phenomena present in breast ultrasound experiments such as attenuation, density, 3D effects, and transducer directivity while maintaining a high resolution.
On the separate recovery of spatial fluctuations in compressibility and mass density in pulse-echo ultrasound imaging using linear inverse scattering
Authors: Schiffner Martin F. , Schmitz Georg
Published: May 2014

In pulse-echo ultrasound imaging (PEUI) of soft tissues, the scattered sound field is governed by spatial fluctuations of the two mechanical parameters compressibility and mass density. Spatial fluctuations in compressibility act as isotropic monopole radiators while spatial fluctuations in mass density act as anisotropic dipole radiators. Conventional strategies for linear image reconstruction in PEUI, e.g., delay-and-sum, minimum variance, and synthetic aperture focusing, exclusively account for monopole scattering. This neglect of the inhomogeneous mass density might be accompanied by a loss of diagnostically relevant information, e.g., the detection of tissue abnormalities. In this study, we formulate a linear inverse scattering problem to recover separate, space-resolved maps of the spatial fluctuations in both mechanical parameters from measurements of the scattered acoustic pressure. The physical model accounts for frequency-dependent absorption and dispersion in accordance with the time causal model. The computational costs are effectively reduced by the usage of the fast multipole algorithm. The concept is evaluated using simulated and experimentally obtained radio frequency data.
A closer look at contrast source inversion for breast cancer detection
Authors: van Dongen Koen W. A. , Ozmen-Eryilmaz Neslihan
Published: May 2014

Ultrasound is an emerging technology for breast cancer detection. It is an efficient and harmless method that can detect tumors in dense breasts, which may be missed using mammography. Currently, several fully automated ultrasound screening modalities are being developed. For some of those systems, accurate knowledge about the transducer location is available, making the measured data suitable for imaging using non-linear inversion methods. A promising, but costly, inversion method is contrast source inversion, which has been tested successfully on synthetic measurement data. To reduce the computational costs (computing time and memory load) various set-ups were tested. Results obtained with synthetic data show that inversion using a single frequency component only, still yielded excellent imaging results, while significantly reducing memory requirements. In addition, our data indicate that the number of source positions is less important than the number of receiver positions. Thus, while keeping the total number of A-scans identical, the inversion improved when the number of source positions was reduced and the number of receiver positions was increased. This approach efficiently reduced the computational costs associated with the inversion.
High-frequency ultrasonic measurement of vascularization in phantoms and Avastin-treated mice with breast tumors
Authors: Quiroz Andrea N. , Cadet Michaelle A. , Doyle Timothy E.
Published: May 2014

Tissue vascularization is an important aspect of tissue engineering and oncology. The objective of this study was to determine if direct ultrasonic measurements in the 10–100 MHz range could be used as an in vivo vascularization assay. To simulate vascularization of tissue, phantoms were fabricated from agarose gel inclusions embedded in a gelatin-soluble fiber mixture. Ultrasonic tests were performed using two broadband ultrasonic transducers centered at 50 MHz. Results showed the samples with multiple agarose vasculature structures decreased the ultrasound wavespeed. As the level of vasculature decreased, the wavespeed of the ultrasound increased. Further investigation of vascularization included the in vivo evaluation of grafted breast cancer tumors in mice. The experimental group was composed of mice treated with Avastin, an angiogenesis inhibitor. The heterogeneity of the vasculature in the control tissue resulted in the scattering of the ultrasound, decreasing the wavespeed. Because the treated group contained less vascularized, more homogeneous tissue, the wavespeed was significantly higher. Results from both the phantom and mouse tumor studies revealed that the ultrasound wavespeed was inversely proportional to the level of vasculature. The results indicate that direct ultrasound wavespeed measurements in the 10–100 MHz range can be used to identify vascularization in tissue.
Overview of Signal Processing in Acoustics
Authors: Culver Richard L.
Published: May 2014

The Signal Processing Technical Committee (SPTC) of the ASA provides a forum for discussion of signal processing techniques that transcend one acoustic application. Signal processing research typically presented at ASA meetings includes techniques that show promise in one application—say underwater acoustics—but may also have application to other areas, for example, speech processing or room acoustics. There are several good reasons to get involved in the SP TC. First, since signal processing is an important aspect of many acoustic research areas, you will have the opportunity to better understand new and potentially useful tools. Second, Signal Processing is a small technical committee and you can make an immediate contribution. This talk provides an overview of some of the current topics in Signal Processing.
The Engineering Acoustics Technical Committee—Where practical applications begin
Authors: Thompson Stephen C.
Published: May 2014

Engineering Acoustics encompasses the theory and practice of creating tools for investigating acoustical phenomena and applying knowledge of acoustics to practical utility. This includes the design and modeling of acoustical and vibrational transducers, arrays, and transduction systems in all media and frequency ranges; instrumentation, metrology, and calibration; measurement and computational techniques as they relate to acoustical phenomena and their utility; and the engineering of materials and devices.
An Introduction to the Musical Acoustics Technical Committee
Authors: Wheeler Paul A. , Morrison Andrew C.
Published: May 2014

The technical committee on musical acoustics (TCMU) is focused on the discovery of novel advancements in the science and technology of music and musical instruments. Many of our members pursue topics related to the physics of musical sound production, music perception and cognition, and the analysis and synthesis of musical sounds and composition. The TCMU draws from many fields represented in the society. Our sessions have presentations made by scientists, engineers, musicians, instrument builders, psychologists, architects, and others interested in the study of the science of music. An overview of selected research topics and activities of the TCMU will be presented.
Overview of Speech Communication research
Authors: Smiljanic Rajka
Published: May 2014

Even though speech communication is a fundamental part of our daily behavior, its mechanisms are not yet well understood. Speech communication research examines how spoken language is produced, transmitted, and perceived. Speech communication research involves a number of different disciplines, from linguistics and experimental psychology to speech and hearing sciences, and electrical engineering. The field covers a wide range of physiological, psychological, acoustic, and linguistic phenomena. In this talk, I will focus on research examining variation in speech intelligibility, the degree to which spoken language can be comprehended. Even in ideal communicative settings, in quiet environments between normal-hearing, native speakers of a language, speech intelligibility is variable. The variation increases in adverse communication situations that can arise from degradation related to talker (e.g., when second language learners produce non-canonical signal), signal (e.g., when target speech is masked by competing speech), or listener (e.g., when listeners use cochlear implants) characteristics (Mattys et al., 2012). Examining speech intelligibility variation from all these perspectives provides insights into the perceptual, physiological, linguistic, cognitive, and neurophysiological mechanisms underlying speech processing. This line of inquiry also has implications for improving speech processing when communicative conditions are compromised.
Biomedical Acoustics: Making a quantum leap in medicine
Authors: Porter Tyrone M.
Published: May 2014

At the dawn of a new era in medicine, the future of biomedical acoustics is bright. In the last century, we witnessed the introduction of ultrasound contrast agents, lithotripsy, and the visualization of ultrasound images in three dimensions. Currently, scientists are developing acoustic-based techniques for opening the blood–brain barrier transiently in order to treat brain tumors and neurological diseases. Additionally, researchers are developing echogenic liposomes and microbubbles for targeted ultrasound image enhancement and drug and gene delivery. Further excitement has been generated by the advances made with focused ultrasound to ablate or mechanically erode solid tumors in a noninvasive and site-specific manner. As technology and protocols continue to evolve, biomedical acoustics will have a dramatic impact on the diagnosis and treatment of debilitating diseases, thus improving patient care and quality of life.
Animal Bioacoustics: Sounds and soundscapes
Authors: Simmons Andrea
Published: May 2014

There is considerable biological diversity in the mechanisms and strategies animals use to produce and to perceive acoustic cues and to communicate and navigate within complex soundscapes. Researchers in animal bioacoustics use a variety of experimental techniques, from passive tracking to active training, to understand and model this diversity. I will highlight recent experimental work from a few model species to show how knowledge of environmental acoustics enhances our appreciation of animal evolution and cognition.
Turning music into sound: Vincenzo Galilei's contributions to the history of acoustics
Authors: Baldissera Pacchetti Marina
Published: May 2014

I investigate the contributions of Vincenzo Galilei (1520—1591), father of Galileo Galilei (1564—1642) to the development of acoustic science, with an emphasis on the role of phenomenology of sound and mathematical explanation of consonances. Sixteenth century music theory mainly aimed at recovering standards of ancient Greek music theory, transmitted by the works of Boethius, and later by Claudius Ptolemy's Harmonics (200 AD). Gioseffo Zarlino (1517—1590), a major exponent of Renaissance music theory, relied on a priori mathematical quantification of sound, which was based on a particular class of so-called Pythagorean ratios. Mathematical properties of these ratios were used to justify a priori the consonance of contemporary music. This clashed with aesthetic perception of sound. Vincenzo argues in favor of the validity of sense perception: perception and aesthetic judgment are explanatory prior to mathematics, and ratios quantify an (undefined) element of sense perception. To prove his point, Vincenzo presented different experiments, demonstrating that the Pythagorean conception of consonance, according to which the octave was embodied by the ratio 1:2, cannot hold for all sound producing physical systems. The study of Vincenzo's experiments in their historical context provide a novel perspective on the relation between the development of scientific inquiry and perception in the history of acoustics.
A comparative study of stringed instruments
Authors: Ramsey Gordon
Published: May 2014

Many studies for stringed instruments exist. Most analyses have been made on violins, guitars, and pianos, but comparative studies on these and less popular instruments have not been done. Our research consists of an in depth analysis of a variety of stringed instruments. The experiments included spectrum analysis, body resonances using Chladni patterns, and high-speed videos to visually observe the string oscillation modes. A combination of these methods was performed on 13 different stringed instruments. The spectral analysis was done on all instruments with the strings plucked or picked at different locations. Corresponding high-speed video was taken on many to observe how the waves propagate along the string. The violin and viola were recorded when bowed to compare the images of the stings when plucked. String resonances were compared to the body resonances to see the synthesis between the two. Comparisons of the spectrum, body resonances, and string oscillations have been made between these instruments to gain a better understanding of how they operate and why each emits the unique sounds that it does. [This paper is complementary to the poster of Katarzyna Pomian at this conference.]
Sounding Brighton: Update on soundscape planning with a user centric approach
Authors: Lavia Lisa
Published: May 2014

The potential of soundscape planning has been widely illustrated in recent years. Sounding Brighton is a collaborative initiative pioneered by the Noise Abatement Society and Brighton and Hove City Council in 2010 with the support of the former COST Action TD0804. The project continues and is exploring the positive effects soundscapes can have on health, wellbeing, and quality of life. It recently undertook a city-wide soundscape survey and interviews leading to “West Street Story,” a night-noise intervention pilot, to gauge whether ambient soundscapes might act as an antidote to the Saturday night drinking culture seen on the city's most dangerous street, and the follow on project: “West Street Tunnel” investigating the same approach in a disused pedestrian subway. The work has also gained inclusion in the Masterplan for the redevelopment of the city center, leading to its willingness to participate in and its acceptance into the European Union funded FP7 SONORUS project looking at holistic ways to include urban sound planning into city planning. This paper will provide an update of the project and its results so far.
Applicability of measurement procedures in soundscape context—Experiences and recommendations
Authors: Genuit Klaus , André Fiebig
Published: May 2014

In the context of the ISO/TC 43/SC 1/WG 54, different aspects of soundscape will be subject to standardization. Besides a standardized soundscape definition, understanding and terminology, minimum reporting requirements for measuring soundscapes including measurement uncertainties are currently discussed and will be subject to standardization later. All in all, a wide range of measurement procedures is applied for measuring, describing, documenting, and analyzing soundscapes. However, several aspects of and conditions for measurements are still unclear, which limits the comparability and compatibility of soundscape investigations. It is evident that a common basis of measurement procedures is needed to bring forward current standardization efforts. Consequently, it is very important to share experiences and knowledge about measurement procedures and their general applicability in soundscape context. A thorough discussion about the data quality achieved by certain measurement procedures is inevitable as well. Observations and experiences made in different soundscape studies regarding different measurement procedures will be presented and discussed with respect to their significance and applicability.
Comparison of momentary and retrospective soundscape evaluations
Authors: Steffens Jochen , Petrenko Johannes , Guastavino Catherine
Published: May 2014

The Peak and End rule describes the effect that retrospective evaluations of temporal events significantly depend on the most extreme affect (peak) experienced during an episode and on the affect at the ending. Other features, like the duration of an event, seem to be widely negligible. We are testing this hypothesis in the context of soundscape evaluation in a series of listening tests conducted in Montréal, Canada, and Duesseldorf, Germany. The soundscapes consisted of recordings of different locations (e.g., railway station, park) and were edited so that there was one presumed emotional “peak moment.” The task of the test group was to indicate momentary judgments by continuously adjusting a slider on a computer interface over the course of the stimulus presentation. Additionally, the participants had to make an overall retrospective rating of the soundscapes after listening to them. To investigate attention effects in the course of the test task a second group was asked to only judge the sounds retrospectively. Preliminary results indicate that the Peak and End rule in combination with the averaged momentary evaluations well predict the retrospective judgments. Within this contribution the results of the experiment will be presented and implications for soundscape design will be discussed.
The sound pressure level observing transponder: A satellite-enabled sensor package for near real time monitoring
Authors: Marchetto Peter , Clark Christopher W. , Aneshansley Daniel
Published: May 2014

Many in situ sensing applications for bioacoustic ecology have suffered from a lack of means to communicate information in near real time. The monitoring of incident noise on an individual animal and its behavioral response to it were the focus of this project. The sensor platform described herein may be used to create acoustic field maps of a habitat in near-realtime.
A novel mode of off-frequency hearing as a result of defective outer hair cells hair bundles unveiled by Nherf1-/- mice
Authors: El-Amraoui Aziz , Kamiya Kazusaku , Michel Vincent , Giraudet Fabrice , Gerogescu Maria-Magdalena , Avan Paul , Petit Christine
Published: May 2014

Nherf1, a PDZ-domain-containing protein, was identified in the hair bundle in differentiating outer hair cells (OHCs). Nherf1-/- mice showed apparently mild hearing-threshold elevations at mid/high sound frequencies, associated to OHC hair-bundle shape anomalies, prominent in the basal cochlea. This mild impact on hearing sensitivity was discordant with the finding of almost non-responding OHCs in the basal cochlea as assessed by distortion-product otoacoustic emissions and cochlear microphonic potentials. Unlike normal mice, responses of Nherf1-/- mice to high-frequency test tones were not masked by tones of neighboring frequencies. Efficient masker tones displayed unusual characteristics: maximal efficiency at lower frequencies (up to two octaves lower than the test tone), and at low levels (up to 25 dB below test-tone level). This, and the relative growth of the masker and test tones, suggests that mid-high frequency tones of moderate intensity are detected off-frequency, in the functionally unaffected apical cochlear region. Our results establish that Nherf1 is critical for hair bundle morphogenesis and reveal a novel mode of off-frequency detection, probably involving the persistent contact between OHCs and the tectorial membrane. These findings suggest how to circumvent major pitfalls in hearing assessment of some patients, by avoiding misleading interpretations of hearing thresholds.
Adaptation reveals automatic pitch-shift detectors
Authors: Mathias Samuel R. , Shinn-Cunningham Barbara , Micheyl Christophe , Oxenham Andrew J.
Published: May 2014

Previous work suggests that the auditory system contains automatic frequency- or pitch-shift detectors (PSDs). These hypothetical units may serve to bind successive sounds together, and appear to be tuned to optimally detect frequency shifts of about 1 semitone. The present work describes several experiments that provide more evidence for PSDs. In all experiments, listeners judged the direction (up or down) of small relevant frequency shifts whilst ignoring prior irrelevant shifts that were usually much greater in magnitude. In almost all conditions and experiments, there was a nonmonotonic relationship between sensitivity to the relevant shift (d') and the magnitude of the irrelevant shift (Δ). d' declined as a function of increasing Δ up to about 1 semitone, and further increases in Δ increased d'. The “dip” in d' could not be explained by selective attention, frequency-specific adaptation, or energetic masking. PSDs provide a convenient explanation for these results if one assumes that (a) listeners discriminate small frequency shifts using PSDs, (b) PSDs are automatically activated by irrelevant frequency shifts, causing them to adapt, and (c) maximal adaptation of PSDs occurs at around 1 semitone.