bluuebunny/crossref_metadata_2025 huggingface dataset:
The fictional environment meets acoustic reality—Simulating and creating acoustical conditions in for laboratory testing
Authors: Barbar Steve , Berger Russ
Published: June 2017

In recent years, we have installed electro-acoustic enhancement systems in specialized acoustic laboratories. These labs incorporate sound isolating environments with loudspeakers that enable multi-channel playback of soundscape recordings that reproduce acoustical conditions of a variety of spaces. In addition, the systems use electronic architecture to carefully match the acoustics of the soundscape recordings to enable live sources in the lab to interact with these environments in real time.
The Rediscovered Engineering Lab Notebooks (1936-1944) of Ben Bauer
Authors: Pettersen Michael S.
Published: June 2017

Benjamin B. Bauer (1913-1979) was an ASA Fellow and awarded the ASA Silver Medal (1978). He held over 100 patents for acoustical/audio technology, with his first patent being arguably the most significant: the invention of the Uniphase principle integral to the Shure Unidyne model 55 microphone. Introduced in 1939 and still manufactured today, the Shure Unidyne was the first unidirectional microphone using a single dynamic element. Today, the Uniphase principle is employed in the vast majority of directional microphones. In September 2016, Bauer’s engineering lab notebooks dating from 1936 to 1944 were located; they had not been seen for over 50 years. The presentation provides a peek into these Bauer notebooks as he discovers and refines the Uniphase principle, as well as numerous other electro-acoustical concepts—some decades ahead of their time.
Room measurement setup for accurate objective analysis and realistic subjective comparison of concert halls
Authors: Neal Matthew T. , Vigeant Michelle C.
Published: June 2017

When measuring a concert hall, a primary goal is to characterize the perceptual aspects of the room’s quality. Since subjective testing requires extensive time and resources, halls are often compared using objective metrics designed to correlate with perception. The goal of the present work is to create a concert hall measurement database that allows for both accurate objective and realistic subjective assessment of concert halls. A 32-element spherical microphone array is used to capture a spatial room impulse response (SRIR) within a hall. A three-way omnidirectional sound source is used for objective measurements, exhibiting omnidirectional behavior up to 5kHz. The omnidirectional SRIR can be used to calculate typical room acoustic metrics and analyzed using beamforming techniques. For a realistic auralization that resembles an orchestral performance, an alternate sound source was used: a compact 20-element spherical loudspeaker. This loudspeaker can be moved around a stage and the measurement signal can be processed to mimic the directivity of different instruments. These individual instrument SRIRs can be combined and processed using Ambisonics to recreate full orchestral auralizations of measured halls. The measurement setup will be presented, along with initial measurement results, and plans for future subjective testing. [Work supported by NSF Award 1302741.]
Why can't I hear that “still small voice”: Did Neolithic noise growth result in human “alienation from nature”?
Authors: Lubman David
Published: June 2017

Did human consciousness change in the transition from the Paleolithic to the Neolithic era? Paleolithic humans lived with nature in small isolated groups of perhaps 30 to 150 people. For survival, Paleolithic hunter gatherers focused their auditory attention on recognizing emerging opportunities and threats. Consequently, Paleolithics were very attentive to weak background sounds. Sound levels often reached “din” levels but it was not noise. The soundscape was signal-rich, reflecting a healthy and resource-rich environment. Neurons of predator and prey evolved to facilitate recognition of the identity, condition, and intention of their natural sources. The Neolithic era that followed emphasized large scale agriculture and herding. Because of the need for organized labor Neolithic farmers were gradually distanced from nature and its sounds. Background sounds no longer signified major threats. With the emergence of cities, over time background sounds became noise. The Neolithic soundscape consisted largely of nearby human and agricultural sounds. So, Neolithic farmers gradually shifted their auditory attention to foreground sounds. Thus, Neolithics gradually lost aural contact with nature. Noise may be an important cause for “alienation from nature,” and for inattention to that “still small voice.”
Evidence for dopaminergic forebrain neurons as modulators of seasonal peripheral auditory sensitivity in a vocal fish
Authors: Forlano Paul
Published: June 2017

Plasticity in sensory and motor circuitry underlies dramatic changes in seasonal reproductive behaviors across vertebrates. In female midshipman fish, seasonal, steroid-dependent plasticity in the auditory periphery functions to better encode frequencies of the male advertisement call. While seasonal changes in number of hair cells and expression of large-conductance, calcium-activated potassium (BK) channels contribute to this change in high frequency encoding, efferent input may also play a significant role in seasonal increases in hair cell sensitivity. We found diencephalic dopamine (DA) neurons directly innervate both the saccule of the inner ear and the cholinergic auditory efferent nucleus in the hindbrain. Ultrastructural investigations using immuno-TEM suggest that DA release occurs in a paracrine fashion in the saccule while inhibitory and excitatory-like synapses are located on auditory efferent neurons. Based on seasonal changes in DA innervation of both these areas, we hypothesized an inhibitory effect of DA on the peripheral auditory system. Pharmacological studies combined with hair cell microphonic recordings confirm a significant inhibition of frequency sensitivity by DA in the saccule. These data suggest that an increase in peripheral auditory sensitivity during the reproductive period results from a release of DA inhibition in the saccule. Our studies support diencephalic DA neurons as important neuromodulators of adaptive seasonal changes in audition for enhanced reproduction in midshipman fish.
First attempt to visualize otolith motion in-situ using synchrotron radiation imaging techniques
Authors: Schulz-Mirbach Tanja , Mittone Alberto , Bravin Alberto , Rack Alexander , Ladich Friedrich , Heß Martin
Published: June 2017

Regarding the basics of ear structure-function relationships in fishes, there is still a substantial lack of knowledge of functional morphology. In particular, the actual motion of the solid otolith relative to the underlying sensory epithelium in the ear has rarely been investigated. To date, analyses of otolith motion have been mainly based on mathematical modeling which have yielded conflicting results. Outcomes of a recent modeling study suggest that otolith motion is not a simple oscillation, but depends on the 3D shape of the otolith, among other factors. Our study thus aims to provide experimental data to test previous models of otolith motion focusing on the relationship between different species-specific otolith shapes and their respective influence on otolith motion. As in-situ investigation of the basic parameters of otolith motion requires an approach with high spatial and temporal resolution, we used synchrotron radiation imaging techniques. In our comparative approach including the anatomically well studied and closely related cichlid species Steatocranus tinanti (vestigial swimbladder) and Etroplus maculatus (swimbladder-inner ear connection), we studied the relative motion of the saccular otolith and surrounding tissues provoked by sound stimuli at 0.2 and 0.5 kHz. We will discuss first results as well as methodological aspects.
Fish bioacoustics, big data, and changing ocean soundscapes
Authors: Rice Aaron N.
Published: June 2017

For many species of vocalizing fishes, reproductive calls form sustained choruses lasting for weeks to months, and are the dominant biological sounds in marine and freshwater habitats worldwide. The timing, duration, and magnitude of these choruses is strongly influenced by environmental factors and may further be influenced by increase in anthropogenic noise. Decades of pioneering work on fish hearing has established a solid scientific foundation to inform what and how fishes hear. By combining this foundation on the auditory system with long-term acoustic recordings of wild populations, we can link organismal-level and population-level processes in fishes to evaluate how they produce, perceive, and respond to sound. The scientific community is now in a place to begin understanding mechanisms and magnitudes of anthropogenic noise impacts on fishes and evaluate how human activities may influence fish populations. An integrative and comparative approach to the study of fish bioacoustics demonstrates how fundamental principles of auditory physiology, behavior, and ecology can inform our interpretation of changing ocean soundscapes.
Changes in fish sound production in the northern Gulf of Mexico over six years
Authors: Širović Ana , Patel Jigarkumar , Hildebrand John , Friedman Sarah
Published: June 2017

Passive acoustics were used to evaluate changes in the presence of soniferous fishes in the northern Gulf of Mexico. Recordings were collected at a site on the continental shelf at 90 m depth, approximately 40 miles east of the Mississippi river delta, from July 2010 through 2016. Seven distinct sounds were detected in 2010 during the first recordings. The occurrence of these sounds over subsequent years was analyzed using automatic detection and classification methods based on convolutional neural networks. Croaks (likely produced by the Atlantic croaker, Micropogonias undulatus) and “jet-ski” calls (likely produced by the Atlantic midshipman, Porichthys plectrodon) were among the most common in 2010 with unique diel patterns. The monthly patterns of calling changed over the six years, likely indicating a change in the fish community structure at this site across the years. Factors that could explain this change include interannual variability due to the extent of anoxic zones, variability in ocean temperature, circulation, or possible impact of the oil spill on fishes in the area. Further investigation on the behavioral context of these sounds would provide insight into likely consequences of the change in calling to these soniferous fishes.
Application of broadband sound for Bighead Carp Hypophthalmichthys nobilis and Silver Carp H. molitrix carps deterrence
Authors: Wamboldt James , Murchy Kelsie A. , Brey Marybeth K. , Amberg Jon J.
Published: June 2017

Withdrawn at author's request.
Auditioning fish for sound production in captivity to contribute to a catalogue of known fish sounds to inform regional passive acoustic studies
Authors: Riera Amalis , Rountree Rodney A. , Juanes Francis
Published: June 2017

Passive Acoustic Monitoring (PAM) is increasingly used as a method to characterize underwater soundscapes and the impacts of noise on marine ecosystems. The natural sounds produced by marine mammals have been widely studied, enabling the use of PAM as an effective conservation tool. However, much less is known about fish sound production, particularly in the northeast Pacific. This lack of information makes it difficult to identify fish sounds that are present in long-term recordings and thus precluding accurate determination of fish species composition and evaluation of the effects of noise on fishes. In order to identify fish sounds in British Columbia soundscapes, we need catalogues of validated fish sounds from Pacific species. These catalogs will help in comparing validated examples to unknown sounds found in long-term autonomous recordings. Our goal is to contribute to building such catalogues and to fill knowledge gaps in fish acoustic behaviour to support studies on the impact of anthropogenic noise on Pacific fishes. We are collaborating with aquaria, ocean-based aquaculture facilities and commercial fisheries to monitor, audition, and record the acoustic behavior of captive and semi-captive fish species. Here, we will present the results of these studies.
Passive acoustic localization of fish using a compact hydrophone array
Authors: Mouy Xavier , Rountree Rodney A. , Juanes Francis , Dosso Stan E.
Published: June 2017

Passive acoustic monitoring of fish in their natural environment is a research field of growing interest and importance. Although many fish species are soniferous, the characterization and biological understanding of their sounds are largely unknown. Many underwater acoustic recordings contain sounds likely produced by fish, but little information can be extracted from them due to the lack of fundamental knowledge about the behaviors they represent. Deploying small hydrophone arrays can help fill some of these knowledge gaps. Passive acoustic localization using fish calls received on multiple hydrophones can be used to estimate swimming speed, calling rate of individual fish, and source level of their calls. This paper focuses on the three-dimensional localization of fish using a compact array of 6 hydrophones using both simulated and measured data. Fish sounds were detected manually on one of the hydrophones. Time difference of arrivals (TDOAs) were then defined by cross correlating the detected signal with signals from the other hydrophones. Linearized Bayesian inversion was employed to localize fish sounds from the measured TDOAs. Localization uncertainties were below 10 cm inside the hydrophone array. Simulated annealing optimization was used to define the hydrophone configuration that could provide the smallest localization uncertainties.
A convolutional neural network based approach for classifying delphinidae vocal repertoire
Authors: Flaspohler Genevieve E. , Silva Tammy , Mooney T Aran , Girdhar Yogesh
Published: June 2017

Delphinidae are known to produce a rich variety of vocalizations whose function and form are not yet completely understood. The ability to reliably identify the vocal repertoire of delphinidae species will permit further exploration of the role acoustic signals play in delphinidae social structure and behavior. This work applies contemporary techniques from human speech recognition and computer vision to automatically classify the vocal repertoire of wild spotted dolphins (Stenella attenuata), using acoustic data collected from hydrophones mounted directly on free-swimming animals. The performance of a variety of machine learning algorithms, including SVMs, random forests, dynamic time warping, and convolutional neural networks, is quantified using data features from both the fields of cetacean acoustics and human speech recognition. We demonstrate that maximal performance is achieved using acoustic spectrogram features in conjunction with a convolutional neural network (CNN), a machine learning technique known to produce state of the art results on image classification tasks. Even on a relatively small dataset (~350 labeled vocalizations), the CNN achieves 86% classification accuracy on eleven unique vocalization types, with groundtruth labels provided by domain scientists. This work demonstrates that a complex, parametric model, such as a CNN, can be effectively applied to small-data domains in ecology to achieve state-of-the-art performance in acoustic classification problems.
Who’s making all that racket? Seasonal variability in kelp forest soundscapes
Authors: Butler Jack , Parnell Ed , Širović Ana
Published: June 2017

Kelp forests off the coast of southern California harbor a myriad of soniferous organisms, creating diverse and complex soundscapes. However, the temporal and spatial variability of kelp forest soundscapes remain poorly documented. Here, the seasonal variability in the soundscapes from two areas, one inside and the other outside a marine protected area off the coast of La Jolla, CA, is described. The din of snapping shrimp snaps was constant in both areas and throughout the seasons, and many distinct, likely fish calls in the 80 Hz—1000 Hz band were heard year-round. Most notably, a late spring/early summer chorus of two putative fish calls (one with most energy at ~90 Hz, the other ~380 Hz) dominated the dusk soundscape of both areas. Many stressors (e.g., pollution run-off, anthropogenic noise, and ocean warming) buffet and degrade the kelp forests of southern California. Documenting how these soundscapes change as the kelp forest conditions change might provide a way to rapidly assess the quality of an area, as well as provide a way to measure the success of conservation techniques and recovery within protected areas.
The ecoacoustics of a kelp forest: Measurement and prediction (Ecklonia radiata)
Authors: Hermand Jean-Pierre , Randall Jo , Ross Jeff , Johnson Craig
Published: June 2017

Despite of over a century of intensive research on kelp (brown macroalgae of the order Laminariales), very few acoustic studies have been undertaken and much remains unknown about their species-specific acoustic properties, which are nevertheless essential for surveying and managing the respective habitats. In this paper, we discuss results of an in-situ, acoustic and ecological investigation of species Ecklonia radiata which forms dense aggregations at Canoe bay, Tasmania (FORTES 12). The experiment measured extensively the time-varying Green’s function (0.2–20 kHz) between pairs of distant source and receivers together with physical and biogeochemical variables of the ecosystem. Propagation and scattering features are interpreted in the light of other results obtained by the authors including ray-based estimation of the channel impulse response envelope, finite-element scattering model of a whole E. radiata thallus, and a study of production from diel oxygen modelling, oxygen exchange, and electron transport rate in the kelp. Comparison will be made with similar experiments carried out in Mediterranean seagrass meadows [Handbook of Scaling Methods in Aquatic Ecology: Measurement, Analysis, Simulation, CRC Press, 2003]. [Work supported by ONR.]
Sound speed and attenuation in seagrass from the water column into the seabed
Authors: Lee Kevin M. , Ballard Megan S. , McNeese Andrew R. , Wilson Preston S.
Published: June 2017

Biological processes and physical characteristics associated with seagrass can greatly affect acoustic propagation in coastal regions. An important acoustical effect is due to bubble production by the plants, which can have significant impact on both object detection and bottom mapping sonars by increasing clutter through reflection, absorption, and scattering of sound. In addition to photosynthesis bubbles and gas-bearing leaf tissue in the water column, the plant rhizomes also contain aerenchyma (gas-filled channels), which allow for diffusion of oxygen into the surrounding sediment. To study these effects, in situ acoustic measurements were conducted in a bed of Thalassia testudium in east Corpus Christi Bay, TX. Direct measurements of sound speed and attenuation were obtained in the water column above the seagrass canopy, inside the seagrass canopy, and at discrete depths within the sediment. A complimentary set of measurements were obtained in a bare sediment region located a few meters away. In addition to standard measurements of geoacoustic properties (sediment density, grain size, etc.), biomass was also estimated from cores collected at each site. The sediment beneath the seagrass bed had significantly lower wave speed and higher attenuation compared to the bare sediment. [Work supported by ARL:UT IR&D program and ONR.]
Anthropogenic noise generated by mobile vehicles used to survey rockfishes in the Channel Islands, California
Authors: Madrigal Brijonnay , Stimpert Alison K. , Yoklavich Mary M. , Wakefield W. Waldo
Published: June 2017

Impacts of ambient noise in the ocean are a concern for fish populations, as well as for other marine vertebrates. The influence of noise associated with mobile equipment, such as autonomous vehicles and occupied submarines used to survey demersal rockfishes (genus Sebastes), has not previously been quantified. Such noise likely occurs within the same low frequency range as sound produced by soniferous rockfish species, whose calls have source levels ranging from 103-113 dB re 1 μPa. A digital acoustic monitoring (DMON) instrument was deployed in association with optical and ultrasonic surveillance cameras in October 2016 off the Channel Islands in Southern California, to quantify mobile vehicle noise and to monitor changes in rockfish behavior during these surveys. The DMON sampled over 5 days for a total of 45.5 h. Analysis of a bandpass filtered (100-500 Hz) data subset showed ambient noise levels of approximately 100 dB RMS re 1μPa, with vehicle activities generating spikes in noise levels of 10-20 dB above baseline. These preliminary results indicate that the DMON captured a diversity of both abiotic and biotic sources of sound, and may indicate local masking of rockfish sounds by survey vehicle noise.
Innovative strategies for improved outcomes in nephrolithiasis
Authors: Bailey Michael , Simon Julianna C. , Kreider Wayne , Dunmire Barbrina , Crum Lawrence , Maxwell Adam D. , Khokhlova Vera , Sapozhnikov Oleg A. , Cleveland Robin , Colonius Tim , Lingeman James E. , McAteer James , Williams James C. , Freund Jonathan
Published: June 2017

Edwin Carstensen, Ph.D., was an advisor of NIH NIDDK Program Project Grant DK043881, created to investigate shock wave lithotripsy (SWL). We now develop solutions to improve all aspects of the management of stone disease. Our goal in this paper is to report progress built on Dr. Cartsensen's advice and inspiration. The work ranges from numerical simulation to clinical trials and from device development to bioeffects and metrology. Much of our work involves bubbles and cavitation. This work has contributed to the body of knowledge defining limits for the safe use of ultrasound which Dr. Carstensen worked hard to establish. Specifically, an update will be given on the development of ultrasound to image, fragment, trap, and reposition stones. In particular, we demonstrated bubbles contribute to the twinkling artifact used by NASA and others to image stones, and we drew on Dr. Carstensen's paper [UMB, 19(2) 147-165 1993] to demonstrate that breathing the elevated carbon dioxide levels present in NASA vehicles suppresses this signal making stone imaging more difficult. We have since developed imaging countermeasures and pushing and breaking technologies that appear less dependent on cavitation than SWL. [Work supported by NIH P01DK043881, K01DK104854, R01EB007643, and NSBRI through NASA NCC 9-58.]
Edwin Carstensen’s contributions to early research at the Navy’s Underwater Sound Reference Laboratory
Authors: Brown David A.
Published: June 2017

Edwin Carstensen enrolled at the Case School of Applied Science to study acoustics under Dayton Miller but upon Miller’s passing in 1941, he took up study under Robert Shankland. The influence of World War II reached deeply into academia in those years and Carstensen’s advisor Shankland became the Director of Underwater Acoustic Metrology at Columbia University—Division of War Research (DWR). Thus Carstensen was first introduced to practical problems in underwater acoustics of critical importance to the Navy as a graduate student and employee (of DWR). At that time, the Underwater Acoustic Metrology center was headquartered in New York City at the Empire State building but established a remote calibration and research facility near Orlando, Florida, which subsequently became the Navy’s Underwater Sound Research Laboratory (USRL). Carstensen began his life-long study of propagation of sound in bubbly media and the effects of cavitation. He also worked on diffraction and calibration of hydrophones by self-reciprocity, the subject of his Master’s thesis that was delayed until 1947 due to his war-effort service. This paper summarizes some of his early work, publications and collaborations in the Underwater Acoustics.
A double-layer acoustic absorber as potential substitute for traditional micro-perforated elements
Authors: Auriemma Fabio
Published: June 2017

A double-layer fibre-less absorber is presented in this paper as possible substitute for Micro-Perforated Element (MPE), at least in room acoustics applications. This absorber is called Micro-Grooved-Element (MGE) since grooves are present on one of the contact surfaces of the two mating layers. These grooves generate a number of micro-channels when the element is assembled. Despite the necessity of having two layers, it is possible to have a certain control of the weight because the layers are provided with wide slits. The MGE offer the advantage of requiring basic manufacturing process (typically milling), instead of the less cost effective laser cut used for MPE. Substituting micro-perforation with engraving allows the generation of micro-apertures which are smaller in cross section and length than in case of traditional MPE, while it is still possible to preserve adequate porosity. In this work, the acoustic performance of MPE and MPE are tested and compared in terms of absorption coefficient and transfer impedance in both linear and non-linear regimes. In case of MGE, the presence of more minute apertures will result in an increase of the absorption coefficient up to ≈30%.
A platform for performance: Making the case for an improved cello podium
Authors: Tagg David J.
Published: June 2017

Stringed instruments such as the cello have been evaluated extensively from structural and acoustical perspectives, but the riser on which a cello sits within the context of a concerto performance has been long overlooked. Being that the podium is traditionally some variation of a hollow box, this riser or “podium” in some regard becomes part of the instrument and can play a productive or even counterproductive role in its acoustic projection. While a cellist’s performance is understood to be enriched and enhanced by this piece of furniture, no one has completed a significant study examining the physics, dimensions, or capabilities of an ideally constructed cello podium. This first installment in a two-part study investigates the mechanical interaction between the musician, instrument, and supporting surface, measuring useful or harmful energy transmitted through the legs of the chair, the musician’s feet, and most importantly the endpin of the instrument.
Guitarists' evaluation and discrimination of steel-string acoustic guitars built with back/side woods of varying price, prestige, and sustainability
Authors: Carcagno Samuele , Bucknall Roger , Woodhouse Jim , Fritz Claudia , Plack Christopher J.
Published: June 2017

The different woods used for the back plates of acoustic guitars are often compared by guitarists for their sound qualities, but these comparisons are rarely done under blinded conditions. For this experiment, six steel-string acoustic guitars were built to be as similar as possible except for the woods used for the backs and sides. Bridge admittance measurements and spectral analyses of acoustic recordings revealed small differences between the guitars in their low-frequency modes. Fifty-two experienced guitar players rated the guitars for sound quality, playability, and other perceptual attributes while wearing welder’s goggles to prevent visual identification. The guitars received on average similar ratings for sound quality and playability. A factor analysis showed that the other perceptual attributes clustered around the dimensions of “clarity,” “warmth,” and “loudness,” which were all positively related to perceived sound quality, and did not differ significantly between the guitars. An ABX discrimination test performed by a subset of 31 guitarists showed that guitarists could not easily distinguish the guitars by their sound. Overall, the results suggest that the woods used for the back plate of a steel-string acoustic guitar have only a minimal influence on its perceived sound, despite varying greatly in price, prestige, and sustainability.
Investigating multimodal perception during the musical performance: The case of harpsichord voicing
Authors: Pate Arthur , Givois Arthur , Le Carrou Jean-Loïc , Castellengo Michele , Le Conte Sandie , Vaiedelich Stephane
Published: June 2017

The plectrum/string interaction appears to be the main phase during which harpsichord players control the instrument's sound quality. This is why both harpsichord players and makers commit themselves to the “voicing process,” a necessary work prior to performance, where the plectra are shaped in order to provide the instrument with a good sound quality and homogeneity over the whole tessitura. Part of a project aiming at understanding the makers' gesture, this paper will present the results of a free playing and verbalization task. This experimental protocol allows (a) the musicians to produce evaluations within an ecologically valid situation, and (b) the experimenters to access the strongly multimodal nature of these evaluations. Two sets of plectra were designed by two professional makers, and given to play to 8 professional musicians during a blind test. Each musician freely played successively both plectrum sets while verbally expressing her/his feelings. The psycholinguistic analysis lead to a perceptual description of each set of plectra, which were found to differ in the perceived hardness of the plectra, the perceived loudness and resonance of the produced tones, as well as the judgment of the sound quality homogeneity and evolution over the tessitura.
Observation of the vocal tract configuration while playing a woodwind instrument
Authors: Kaburagi Tokihiko , Fukuda Yuri
Published: June 2017

Skillful players of brass instruments and reed woodwinds are able to control the vocal tract effectively and perform with intended pitches and sound qualities. The player’s vocal tract is, to a first approximation, connected with the instrument bore acoustically in series. If the magnitude of the vocal tract impedance is comparable with the bore impedance, the acoustic pressure in the mouth can then exert influences with a vibrating reed. However, studies reliant enough to confirm the configuration of the vocal tract while playing are limited. In this study, a magnetic resonance imaging (MRI) device was used to scan the vocal tract in three dimensions. The participant was an amateur saxophone player and the instrument was made from reed, mouthpiece, and a short uniform tube. Image data revealed how the vocal tract was formed when she blew a number of different notes. They were also used to determine the cross-sectional area and the input impedance of the vocal tract. The results were compared with trumpeter data taken and published previously, and also with data taken for the act of whistling. [This work was supported by JSPS KAKENHI Grant Number JP16K00242.]
Applying information theory to investigate music performance with continuous electronic sensors
Authors: Berdahl Edgar J. , Blandino Michael , Shanahan Daniel
Published: June 2017

A wide variety of electronic sensors can be used for designing new digital musical instruments and other human-computer interfaces. However, presently human abilities for continuously controlling such sensors are not well quantified. The field of information theory suggests that a human together with a user interface can be modeled as a communication channel. Previously, Fitts' Law used a discrete communications channel to model information conveyed by a human pointing at discrete targets. In contrast, the present work employs a continuous communications channel to model a human continuously controlling an analog-valued sensor. The Shannon-Hartley theorem implies that the channel capacity (e.g., HCI throughput) can be estimated by asking human subjects to perform gestures that match idealized, bandlimited Gaussian “target gestures” across a range of bandwidths. Then, the signal-to-noise ratio of the recorded gestures determines the channel capacity (e.g., HCI throughput). This approach is tested on human users alternately operating simple analog sensors. Suggestions are made for creating knowledge about user interfaces that could potentially transmit an enhanced amount of information to a computer.
Relationship between frequency characteristic of fluctuated sound and detectability of warning sounds for electrical vehicle
Authors: Yasui Nozomiko , Miura Masanobu
Published: June 2017

The sound on electrical vehicle is quiet at low speeds, so pedestrians have difficulty recognizing electrical vehicles approaching them. Those vehicles were designed to play a warning sound to solve this problem. However, it has not been solved yet, and the introduction of warning sounds is broadly discussed on different political levels. It is necessary to design warning sound to concern detectability of approaching electrical vehicle in order to make it easier for pedestrians to recognize the vehicle. Our previous studies investigated detectability of fluctuating sound, and then found that the fluctuation frequency, non-periodic fluctuation and shape of envelope are effective to enable people to recognize approaching vehicles. However, frequency characteristic of fluctuating sound used in those studies was one pattern, namely motor sound. Here, we investigate relationship between frequency characteristic of fluctuated sound and detectability of warning sounds for electrical vehicle. Investigations were carried out by using different fluctuated sounds which were designed to have periodic and non-periodic fluctuations, and their detectability by pedestrians were assessed. The results revealed that the frequency characteristic of fluctuated sound influences the ability with which people detect approaching electrical vehicles.
A modeling approach in simulating vibro-acoustic responses of electric motors
Authors: Arabi Samaneh , Steyer Glen , Sun Zhaohui
Published: June 2017

The trend of electric or hybrid-electric vehicles in today’s automotive industry brought new challenges into science and engineering world including the Noise and Vibration issues, which are usually tied up with both airborne and structural noises. The electromagnetic force typically plays a significant role in acoustic noise radiation in the electric motor. This paper describes an innovative approach to model the physics of noise radiated by the electric motor. The dynamic response of the structure is obtained by modal decomposition of the electromagnetic radial force. The stator structure is considered as an equivalent cylinder subjected to sinusoidal distributed modal loads. The mathematical formulations of the modal forces are implemented in Finite Element Modelling. An acoustic FE model is used by taking the vibration velocity of the housing structure as a boundary condition for calculating the noise radiation. This methodology provides a better fundamental understanding of how the electric motor as a noise and vibration subsystem behaves, and facilitates design parametric studies and optimization. The approach is validated by comparing the predicted vibration and noise from an electric model to experimental test data, and excellent agreement is obtained.
A multipole expansion technique for predicting en-route aircraft noise
Authors: Wang Yiming , Li Kai M.
Published: June 2017

This study investigates the noise emitted by aircraft overflights. A multipole expansion method is used to model the noise source generated by propeller-driven aircrafts. Indeed, the multipole expansion method is frequently used in the study of electromagnetic wave propagation in which the far-field potential due to a localized charge distribution is approximated. This same technique is equally applicable in acoustics where the directivity of the aircraft noise source is modeled by summing a series of multipoles. For instance, the zero, first and second moment represent a monopole, dipole, and quadrupole, respectively. The first moment term is omni-directional and high order multipole terms have shown increasingly strong dependency on the receiver’s angular positions. The multipole expansion method leads to a more accurate model for evaluating the directivity effect due to aircraft flyovers. In the current study, precise (comprehensive) experimental data were used to determine the strength of each multipole term by means of non-linear least squares optimization. Our preliminary results have demonstrated that higher order multipoles up to and including quadrupole terms are needed to give reasonable predictions of the sound fields. [Work Sponsored by the Federal Aviation Administration.]
Enabling noise engineering methods to model complex geometries
Authors: Kamrath Matthew , Jean Philippe , Langrenne Christophe , Picaut Judicaël
Published: June 2017

Many governments use standard engineering methods (e.g., CNOSSOS or Nord2000) to model outdoor noise propagation from cars, trains, and trams. These methods provide efficient approximations of long-term averaged noise levels based on the geometrical divergence, atmospheric absorption, ground effect, refraction, reflection, and diffraction. However, these methods are limited to diffraction around simple, box-shaped geometries; for example, engineering methods cannot model a T-barrier. In addition, reference methods like boundary elements or finite differences are too computationally expensive for many realistic cases. Thus, a hybrid method has been developed to improve the accuracy of the engineering methods for complex geometries and surfaces. This approach interpolates a table of 2.5D boundary element results to estimate the influence of the complex objects. The hybrid method produces more accurate results than the standard engineering methods compared to a fast-multipole boundary element method for a small test case using a T-barrier up to almost 2 kHz. However, significant differences between the hybrid and boundary element methods remain because the boundary element method sums the pressures coherently and the hybrid method sums them incoherently like the engineering methods do for simplicity and efficiency.
Sound propagation methods for road traffic noise auralization
Authors: Muirhead Matthew , Southern Alex
Published: June 2017

When changes to an area involving an upgrade to a road network (new or existing) are planned, an assessment of the potential for change in the sound environment is carried out. However this assessment usually only considers local residents’ daily noise exposure and it can be difficult to understand what an increase of 2 dB, for example, actually means in terms of what you hear. Further to this, perceived changes in sound character in relation to road traffic and associated noise mitigation measures are not assessed by current methodologies. There has been increased interest recently in auralization as a potential environmental sound design tool. Without the existence of standardized guidance on the application of existing sound propagation models for auralization there is a potential to obtain a wide range of perceptually different results, depending on the adopted methodology. This work discusses important considerations for the auralization of road traffic noise. Accurately creating these experiences requires bringing together existing sound recordings with the latest and most advanced methods for traffic and environmental noise modeling. Here we discuss some proposed algorithms and methods for achieving this and potential improvements to the nascent methodology for the future.
A method for plausible road tyre noise auralization
Authors: Southern Alex , Murphy Damian
Published: June 2017

Interest in research relating to the impact and abatement of road traffic noise has increased since the Environmental Noise Directive was introduced. The World Health Organisation has recognized road traffic noise as a serious problem for public health, and annoyance with some aspect of our daily soundscape is well recognized as a common complaint. Auralization tools can allow designers, planners and relevant stakeholders to listen and converse on human response to a planned development or mitigation strategy. An ideally detailed road traffic noise auralization system would render the acoustic emission of every vehicle on the road network at any desired receptors. This work focuses on the sound emission from the road tyre interaction for the purpose of auralization and extends on previous work for synthesising road tyre noise based on a small dataset of roadside recordings. The proposed method discussed in comparison to a recently published approach and the plausibility of the proposed method is verified.
Identification of acoustic moving sources in the context of a road vehicle at pass-by: A numerical comparison
Authors: COUSSON Remi , PALLAS Marie-Agnes , Leclerc Quentin , BERENGIER Michel C.
Published: June 2017

The problem of the identification of acoustic sources has been widely treated in static or quasi-static source contexts, more recently for moving sources, in a wide range of applications. Different methods have been developed in this endeavor. In the context of identification of sources from a passing-by vehicle, the beamforming method is a reference that has well-known limitations: a poor resolution at low frequencies causes difficulties to discriminate close sources or with too different levels, and the convolution of the point spread function with the source-signal makes it difficult to evaluate the level precisely. Deconvolution methods are used to overcome those limitations. Mostly developed in static contexts at the beginning, extensions to moving sources have been proposed in the transportation field, mainly in air transportation and underwater acoustics. In the present investigation, these methods are numerically tested with parameters fitted to the road vehicle context. Their performance is assessed at different speeds, with varying additional noise levels. Beamforming—as the reference method—and several deconvolution methods (DAMAS, CLEAN, NNLS) extended to moving sources are compared using performance including: location of the maximum, source gravity center, maximum level and extended level. Illustrations involving an academic pendulum setup are given.
Warning sound generation system of an electric vehicle system
Authors: Han Man Uk , Lee Sang Kwon
Published: June 2017

Electric Vehicles (EV) generate sound pressure lower than internal combustion engines(ICE) at low speed. Pedestrians familiar with internal combustion engines are difficult to recognize such a quite vehicles. Therefore, an additional warning sound generator is required. The warning sound must have high detectability and low annoyance to pedestrians, while complying with legislation for warning sound of various countries. In this paper, we design the electric sound with detectability and low-annoyance. An active generation system is also designed based on active sound design and in attached in the electeic vehicle to generate this sound. The sound is validated with subjective test in the running condition on the road.
Estimation of incident energy angular distribution at the building envelope in urban environment
Authors: Stanojević Miodrag , Bjelic Miloš , Sumarac Pavlovic Dragana , Mijić Miomir
Published: June 2017

This paper presents preliminary results of a research dedicated to noise analysis at the building envelope using microphone arrays. Motif for such a research is a dependence of façade elements insulation characteristics on incident angles of noise impeding a façade. The goal is to determine the influence of different building and street configurations on the discrepancies between laboratory and in-situ values of façade elements sound insulation, and develop a model for predicting in-situ façade performances depending on building surroundings. Microphone array mounted on a façade can provide an insight into impeding noise energy distribution over angles of arrival. This distribution is examined for a number of different scenarios, including buildings in canyon and non-canyon streets, different mounting heights of the array, different widths of streets etc. Planar array consisting of 24 microphones with a diameter of 2.2 m is used for measurements. Results for given scenarios are presented and compared with a discussion on building surroundings influence on the performances of their façade elements.
Dredge noise control
Authors: Bommer Arno S. , Young Adam
Published: June 2017

When dredges operate near residences, noise can be a concern. The major noise sources of a dredge can include diesel engines (casing and exhaust), generators, transformers, ventilation fans, electric motors, pumps, and winches. Some equipment is enclosed and some is on the open decks. Both airborne and structure-borne noise can be issues. As the dredge operates, its location and orientation relative to residences continuously change. Noise data and treatments are discussed from several dredging projects.
Transportation noise exposure is strongly correlated with increased morbidity and mortality
Authors: Fink Daniel
Published: June 2017

Transportation noise has long been considered just a nuisance but numerous studies now show that transportation noise exposure is strongly correlated with increased morbidity and mortality. Noise interferes with human activity at 45 decibels. Nighttime noise interferes with sleep, needed for optimal human health and function. At 55 decibels daily time-weighted average (TWA), noise causes increases in stress hormone levels, correlated with changes in lipid and glucose metabolism, hypertension, stroke and heart disease, and hospitalization and death. At 70 decibels TWA, noise causes hearing loss. Other than death, the non-auditory effects of noise on health are small for each individual, but great in aggregate. Approximately 100 million Americans are exposed to noise loud enough to damage health. The loss of the nighttime quiet perioid in cities is a major contributor to this problem. Technologies for a quieter America are well known and, with the exception of those needed to reduce aircraft noise, neither difficult nor costly to implement. The goal for both human exposure and noise from all sources, adapted from the Nuclear Regulatory Commission, should be ALARA, As Low As Reasonably Achievable. Acoustics professionals must work with physicians and other health professionals to accomplish this.
On the atmospheric-driven variability of impulse sounds
Authors: Cheinet Sylvain , Christoph Markus , Collier Sandra L. , Cosnefroy Matthias , Ehrhardt Loic , Königstein Florian , Ostashev Vladimir E. , Rickert Winfried , Stefanovic Alexandre , Wessling Thomas , Wilson D. K.
Published: June 2017

Sound propagation is largely affected by the near-surface conditions (ground type, turbulence, and weather). The presentation reports on a joint research effort aimed at improving fundamental understanding of these propagation effects on impulsive sounds. Data collections will be presented, which consist of measuring transient acoustic signals at distance from a reproducible sound source, under a variety of acoustic-atmospheric conditions. Analysis of these data, supported by theoretical studies and numerical simulations, is conducted to reveal how the environmental conditions drive the observed variations of acoustic pulses. Challenges in measurements, simulations, and analysis will be discussed.