bluuebunny/crossref_metadata_2025 huggingface dataset:
A simplified approach to virtual reality and auralizations for architectural acoustics
Authors: Buckley Christopher , Bernardi Giuliano
Published: November 2016

The use of auralizations to convey important architectural acoustics design decisions is well known, but the use of accurate auralizations paired with virtual reality (VR) are typically limited to new, large-budget constructions. Smaller-budget projects often cannot afford the expensive software packages necessary to perform such auralizations, or are limited by design time or computational resources. In order to provide accurate VR-enabled auralizations for a larger variety of projects, this paper demonstrates a simplified method which can be used with a pre-calibrated combination of a smartphone and headphones. The presented method allows for modeling room-to-room sound transmission in addition to 3D spatialization cues from early reflections and reverberation. The room-to-room sound transmission is handled by simple filtering operations, which simulate the transmission loss of the demising partition, while the 3D spatialization cues are generated from one of the many freely available spatialization engines such as the Oculus Native Spatializer or Google VR Spatial Audio. This simplified method does not intend to replace existing more robust solutions, but instead allows for a more wide-spread usage of VR-enabled auralizations in cases where a high performance computer or detailed 3D model are not available.
Numerical study on the absorption performance of MPP sound absorber installed in small rectangular rooms
Authors: Okuzono Takeshi , Sakagami Kimihiro
Published: November 2016

Sound absorbers using microperforated panel (MPP) are one of the most promising alternatives of the next-generation sound absorbing materials, thanks to the superior material performances in durability, weatherability, recyclability, and flexibility of design, as well as the attractive broadband sound absorption characteristics. Many previous researches focus on the development of absorbers itself. However, in order to bring out the absorption performance sufficiently or to use it appropriately in room acoustics applications, it is important to understand the absorption effect of MPP absorbers on sound fields in rooms. For the purpose, recently, highly accurate wave-based acoustics simulation techniques such as FEM can be used to analyze sound fields in practical sized rooms with MPP absorbers. This paper presents the absorption performance of MPP absorbers installed in a small rectangular room of 91 m3 using 3D-FEM in frequency domain. Both the steady-state and the unsteady-state sound fields are calculated up to 1 kHz under the various absorber locations. The unsteady-state sound fields are calculated using inverse Fourier transform of transfer functions of rooms. The results are compared to explore the optimum sound absorber locations.
Increasing liveness and clarity in a multipurpose civic center
Authors: Michel Hans , Myers Joseph
Published: November 2016

The Des Moines Civic center recently underwent a renovation primarily for symphonic uses, to improve hearing conditions on stage and in the house. This renovation included a new movable orchestra shell, rebuilt rear wall, and new finishes at sidewalls. The original shell did not adequately support bass or project sound to the audience, and musicians reported communication problems on stage. The rear wall was typically covered by a curtain, and returned confusing echoes when the curtain was withdrawn. The most unusual aspect of the room was the design of its sidewalls, broken into convex, down-leaning pylons, a signature of Paul Veneklasen, the original acoustician. KA analyzed the reflection pattern off the side walls and devised a treatment that maintained the beneficial aspects of the original design while dramatically improving clarity and presence. This paper focuses on the testing and modeling methods used to confirm our hypotheses about the problems caused by side wall reflections; the selection of appropriate materials based on in situ measurements and subjective listening; and architectural coordination.
Blue whale song sequencing off Southern California
Authors: Lewis Leah A. , Calambokidis John , Hildebrand John A. , Širović Ana
Published: November 2016

Blue whales off Southern California produce a unique song consisting of pulsed A unit and tonal B unit calls. These units are either sequenced in an alternating AB pattern, or a single A unit is followed by multiple B units (here denoted ABB). To investigate whether there is geographic variation in the occurrence of these different sequence types, data were analyzed from four High-frequency Acoustic Recording Packages deployed at two sites each inshore and offshore of the Channel Islands from September 2009 to June 2010. Additionally, fine-scale behavior associated with song and its sequencing was analyzed from acoustic tags deployed on blue whales in Southern California since 2000. A higher proportion of song bouts detected in offshore recordings were type ABB, whereas the dominant song type observed inshore was AB. This pattern may indicate geographic variability in song function. Most song units recorded on tags were produced during surface-travel dives, with the whale less than 30 m deep. Song bouts detected on tags occurred primarily at night, and whales did not interrupt their calling sequence with breathing intervals. The observed differences in calling and song preference off Southern California may be useful in identifying regionally distinct behavioral contexts for blue whales.
Acoustic multi-tasking in beaked whales: The use of alternating echolocation regimes during the descent phase of deep foraging dives
Authors: Trickey Jennifer S. , Baumann-Pickering Simone , Hildebrand John A.
Published: November 2016

Beaked whales use echolocation to navigate and hunt at extreme depths, and the timing of their echolocation clicks while actively searching for prey is generally characterized by a stable inter-click interval (ICI). However, analysis of autonomous, long-term passive acoustic data revealed a markedly different pattern during the vocal portion of their descent towards the seafloor. Diving beaked whales were found to alternate between two ICI regimes, while also gradually increasing their overall click rate. This strategy is presumably used to simultaneously monitor two different target ranges as they approach their preferred foraging depth. One ICI regime likely corresponds to the two-way-travel time of sound to the seafloor, and by examining the rate at which the time interval between clicks decreased in this seafloor-tracking ICI regime, we calculated estimates of dive descent rate. The second ICI regime was consistently more rapid, and represents a shorter search range that is likely used by the whale to inspect the nearby water column for the presence of prey and other features. This unique echolocation behavior was identified in acoustic encounters of four different species of beaked whales recorded at a variety of sites in the North Pacific Ocean and the Gulf of Mexico.
Detection of marine mammal vocalizations off Cape Hatteras, modulated by the Gulf Stream
Authors: Lockhart Stephen B. , Dubbs Lindsay L. , Muglia Michael , Taylor Patterson , Todd Robert E.
Published: November 2016

To assess the ecological impact of extracting energy from the Gulf Stream, the University of North Carolina Coastal Studies Institute has deployed a mooring on the continental slope off Cape Hatteras at a depth of 230 m, equipped with an ADCP, a CTD, and a hydrophone. Analyzing data from the first deployment, we automatically detected marine mammal vocalizations. We found a strong correlation between the amount of vocalizations and the position of the Gulf Stream, with vocalizations increasing when the Gulf Stream was farther offshore. We then derived sound speed profiles for the region around the mooring using temperature and salinity profiles collected by WHOI Spray gliders. These sound speed profiles were fed into a propagation modeling tool. When the Gulf Stream was far offshore with respect to the mooring position, the model showed a set of rays that propagate down the slope in an acoustic channel along the bottom. When the Gulf Stream was nearly over the mooring, the range of angles that could propagate down the slope was reduced by a factor of six. Therefore, the propagation models suggest that the observed correlation is due to a propagation effect, resulting from the varying position of the Gulf Stream.
A first look at the Ocean Noise Reference Station Network: The soundscape of Stellwagen Bank National Marine Sanctuary
Authors: Haver Samara M. , Klinck Holger , Van Parijs Sofie , Matsumato Haruyoshi , Dziak Robert P. , Gedamke Jason , Hatch Leila T.
Published: November 2016

In order to compare long-term changes and trends in soundscapes around the United States, a multi-year network of identical autonomous passive acoustic recording systems, the Ocean Noise Reference Station (NRS) Network, has been established. In partnership with the National Oceanic and Atmospheric Administration (NOAA) Office of Oceanic and Atmospheric Research, NOAA Pacific Marine Environmental Laboratory, NOAA National Marine Fisheries Service, NOAA Office of National Marine Sanctuaries, and the National Park Service, hydrophone moorings were deployed in 12 discrete soundscapes in the Northeast Pacific and Northwest Atlantic oceans to record underwater ambient sound levels in the 10 to 2200 Hz frequency range. This initial analysis utilized the first year of available data from the NRS deployed in Stellwagen Bank National Marine Sanctuary (SBNMS), a busy area for both natural and anthropogenic activity. Preliminary results indicate that: (1) broadband (10-2200 Hz) ambient sound levels at SBNMS are stable year round in association with constant vessel activity in the nearby shipping lane to Boston, MA, (2) surface wind speed is positively correlated with broadband noise levels, (3) intensity of low-frequency baleen whale calling activity varies seasonally, but signals are acoustically detectable year-round. Future analyses will compare the soundscapes of all 12 NRS sites.
Detection and localization of whale vocalizations in archived data of seafloor cabled observatories in eastern Japan
Authors: Iwase Ryoichi
Published: November 2016

Through the examination of archived OBS (Ocean Bottom Seismometer) waveform data of seafloor cabled observatories in the eastern Japan, fin whale vocalizations were detected. Most of those vocalizations were observed with a single OBS because of the sparseness of the OBS deployment. At the observatory off Kushiro-Tokachi in Hokkaido, the fin whale vocalizations were localized using waveform data of both OBS and hydrophone at the same site (Iwase, 2015). At the observatory off Kamaishi in Tohoku District composed of OBSs without a hydrophone, seismic wave velocities in sediment, which are necessary parameters in estimating horizontal range of sound source from apparent emergence angle of transmitted wave at seafloor, were estimated in situ based on air gun signal observation (Iwase, 2016). By using those results, the fin whale vocalizations were localized. At the observatory off Hatsushima Island in Sagami Bay, sperm whale vocalizations were detected in the audible sound signals of a single hydrophone which were recorded on the soundtrack of video tapes with seafloor images. To date, more than 7000 video tapes recorded since 1993 have been archived, and the result of analysis in progress will be shown at the presentation. References: Iwase (2015), DOI: 10.7567/JJAP.54.07HG03. Iwase (2016), DOI: 10.7567/JJAP.55.07KG01.
Demonstration of limited infrasonic sensitivity in the mallard duck (Anas platyrhynchos)
Authors: Hill Evan M.
Published: November 2016

The purpose of this study was to determine the hearing range and sensitivity of the mallard duck, for the comparative purposes of identifying if the detection of infrasound (i.e., frequencies below 20 Hz) is a common feature of the avian auditory system. Prior to this work, only two species have had their low-frequency sensitivity fully assessed: the domestic pigeon (Columba livia), and the domestic chicken (Gallus gallus domsticus). Both species showed sensitivity to infrasonic acoustic signals as low as 2 Hz. The results of this study found the mallard to have a limited ability to detect infrasound, but inability to detect signals below 16 Hz. Given the lack of sensitivity to infrasound relative to what was observed in other species, this ability likely has limited functional value for this species. Future research on the topic should focus on developing a comprehensive theory that would allow for the selection of avian species for testing, to determine the origin and purpose of infrasonic sensitivity in birds.
Cicada sound impacts avian dawn chorus in a subtropical forest of Taiwan
Authors: Chen Yi C. , Ding Tzung S.
Published: November 2016

Acoustic space is a limited resource for animal communications. To reduce signal competition, animals could differentiate their acoustic frequency range or time to produce sound. Many birds call or sing at dawn for higher signal transmission efficiency. However, in tropical and subtropical forests, the dawn chorus were frequently interferenced by cicadas. In order to examine the effect of cicadas on the avian dawn chorus, we used automated acoustic recorders at subtropical forest of Yangmingshan National Park, Taiwan, to monitor acoustic signals of eight bird species and three cicada species. We found that all bird species postponed their acoustic activities during cicada's breeding season. Meanwhile, we also found frequency partitioning of acoustic signals between birds and cicadas when their acoustic signals overlapped temporally. The results show that cicadas could play a crucial role in the avian dawn chorus. Birds would delay their signal producing time and acoustic frequency to partition the acoustic niche.
The relationships between vocalizing bearded seals and sea ice extent in the southern Chukchi Sea
Authors: Jimbo Mina , Mizuguchi Daisuke , Tsujii Koki , Miyashita Kazushi , Mitani Yoko
Published: November 2016

Bearded seal Erignathus barbatus is one of ice-obligate species, which breeds on seasonal sea-ice in the Arctic and sub-Arctic during March-May. They are threatened by the rapid changes in the Arctic environment due to recent climate change, which causes sea-ice reduction or transition of their prey biomass. To understand the seasonal distribution of bearded seals and assess the impacts of climate change, we deployed the underwater sound recorder at the Southern Chukchi Hotspot (SCH) (67.72oN, 168.83oW) during July 2012-October 2015. Calls of bearded seals were manually detected from September before sea-ice formation started, temporarily decreased during late-November-early-December when sea-ice were formed and increased again from January to the end of our recording periods (March 2013, May 2014 or June 2015) when the SCH were freezing. Combined with previous study, our results indicate that bearded seals come to the SCH from the northern part (i.e., Beaufort Sea) in September possibly to forage, and some move southerly to their breeding area (i.e., Bering Sea) coincident with sea-ice formation. These results suggest that seasonal distribution and vocal activity of bearded seals at the SCH, which are tied with sea-ice, might be changed by the Arctic sea-ice decline in the future.
Size estimation of a giant jellyfish Nemopilema nomurai using quantitative echosounder in the East China Sea
Authors: Matsuura Tomohiko , Abe Koki , Yamada Haruya , Kiyomoto Yoko
Published: November 2016

The maximum bell-diameter of giant jellyfish Nemopilema nomurai is over one meter. They are transported by the Tsushima current to the Sea of Japan and are sufficient to seriously damage coastal fisheries. It is necessary to monitor the population and the distribution of them for reduction of the damage. Therefore, acoustic-optical surveys of the giant jellyfish have been conducted around the Tsushima Strait by a visual observation, a quantitative echosounder (EK60, SIMRAD) and an underwater video camera from 2009 to 2014. The giant jellyfish’s size estimation method using an echotrace height was developed on the surveys. Using the method, the habitat and size distribution were obtained around the East China Sea in June and July 2015 to confirm the appearance of them earlier. The giant jellyfish were distributed from surface to about 40 m depth as results of the quantitative echosounder and the visual observation. The measured bell-diameter range was from 30 to 80 cm and giant jellyfish about 60 cm was most detected by the visual observation. The estimated bell-diameter range using the quantitative echosounder was from 10 to 80 cm. The value of highest frequency was 53 cm and agreed with the result of the visual observation.
Statistics of the backscattered returns from random aggregations of omnidirectional point scatterers and comparisons to fish schools measurements
Authors: Mookerjee Adaleena , Dowling David R. , Benoit-Bird Kelly
Published: November 2016

Remote assessment of scattering objects in the ocean by analyzing the statistics of backscattered returns has been of interest for decades. This presentation describes how simulated and measured backscatter results may be combined to assess the natural variability of fish density in extended schools. The simulations were based on numerical solution of Foldy’s (1945) equations for harmonic illumination of spherical and spheroidal aggregations of randomly-placed omnidirectional point scatterers. The aggregations contained hundreds to thousands of scatterers, and varied in size from 12 ≤ ka ≤ 32, where k is the acoustic wave number and a is the aggregation’s volume-equivalent radius. Based on thousands of realizations, simulated backscattered returns were found to be Rayleigh distributed independently of the scatterers’ and aggregations’ characteristics. However, the distribution of volumetric scattering strengths from echo-sounder measurements from natural fish schools is broader. When taken together, the two results suggest that backscattering from natural aggregations of fish might be well described by a weighted superposition of Rayleigh distributions with the weighting function being a natural aggregation characteristic that can be remotely monitored. Results from simulations and measurements at 38 kHz and 120 kHz are shown and compared. [Work supported by ONR and UM Advanced Research Computing.]
Broadband target strength measurements of juvenile walleye pollock (Theragra chalcogramma)
Authors: Amakasu Kazuo , Mukai Tohru , Yamamoto Jun , Hayashi Hiroki , Iida Kohji
Published: November 2016

Walleye pollock (Theragra chalcogramma) is one of very important fisheries resources in Japan. The acoustic-net surveys have been conducted around Hokkaido since 1995. To improve the present resource management, the estimation of the standing stock of juvenile walleye pollock is necessary. The target strengths of juvenile walleye pollock at 38 kHz have been well-studied through measurement. However, there are little knowledge of the target strengths at frequencies other than 38 kHz. In this study, therefore, the target strengths at other frequencies were measured. The acoustic system was consist of a broadband transducer and commercially available equipment. The calibration of the system was performed by using a 20.6-mm-diameter tungsten carbide sphere. The transmitting signal was 20-160 kHz linear frequency modulated signal. The target strengths of nine specimens were measured and their fork lengths were ranged from 6.9 to 12.1 cm. Each individual specimen was anesthetized and tethered in a tank (5 m x 5 m x 5 m) with a thin fishing line. Orientation angles of the specimen were varied between −50 to 50 degrees and the target strengths were measured at each angle. Orientation and length dependences of the target strengths are presented and discussed.
An inter-individual communication biotelemetry system using Pseudo-random noise (Gold code)
Authors: Minamoto Yoshinori , Arai Nobuaki , Mitamura Hiromichi , Unhid Keiichi , Kimura Satoko S. , Miyashita Kazushi , Shirakawa Hokuto , Tsuda Yuichi , Kitagawa Takashi , Yap Minlee
Published: November 2016

Recently, bio-logging techniques involving electronic data-storage tags (data-logger) and acoustic transmitters have been increasingly used to understand migratory fish movements and behaviors. The monitoring of migratory fish can provide important insights into the marine ecosystem dynamics. The number of tags data-loggers used, however, is normally limited due to cost and the data-logger recovery rate is usually low. Therefore, we developed a new system that combines the acoustic communication and data logger. In other words, a data-logger that can share data with each other. One of the challenges is to develop an inter-individual communication biotelemetry system based on hydro-acoustic methods. In this system, we used the phase modulation of pseudo-random noise (Gold code). At the final stage of development, we will be doing conduct a field test of this inter-individual communication biotelemetry system on wild herrings and bonitos in the open sea. We expect this new technology to help overcome the bottleneck of the conventional bio-logging and bio-telemetry, and lead to a breakthrough in marine ecosystem studies.
Global access to sonar data: Where can it take you?
Authors: Wall Carrie C. , Anderson Charles , Jech Michael
Published: November 2016

Scientific echosounders aboard NOAA fishery survey vessels are used to estimate biomass, measure fish school morphology, and characterize habitat. These surveys produce large volumes of data that are stored locally and difficult to access. Data that are easily discoverable and accessible provide valuable information beyond their original collection purpose. NOAA’s National Centers for Environmental Information, in partnership with the National Marine Fisheries Service and the University of Colorado, created a national archive for the stewardship and distribution of water column sonar data. A data access web page allows users to query the metadata and access the raw sonar data. Visualization products allow researchers and the public to understand the quality and content of large volumes of archived data. Such products transform the complex raw data into a digestible image and are highly valuable for a broad audience of varying backgrounds. Concurrently collected oceanographic and bathymetric data are being integrated into the data access page to provide an ecosystem-wide understanding of the area surveyed. Benefits of the archive include global access to an unprecedented nationwide dataset and the increased potential for researchers to address new questions to advance the field of marine ecosystem acoustics.
Modeling and experimental analysis of acoustic cavitation bubble clouds for burst-wave lithotripsy
Authors: Maeda Kazuki , Colonius Tim , Kreider Wayne , Maxwell Adam , Bailey Michael
Published: November 2016

Understanding the dynamics of cavitation bubble clouds formed inside a human body is critical for the design of burst-wave lithotripsy (BWL), a newly proposed method that uses focused ultrasound pulses with amplitude of O(10) MPa and frequency of O(0.1) MHz to fragment kidney stones. We present modeling and three-dimensional direct numerical simulations of interactions between bubble clouds and ultrasound pulses in water. We study two configurations: isolated clouds in a free field, and clouds near a rigid surface. In the modeling, we solve for the bubble radius evolution and continuous flow field using a WENO-based compressible flow solver. In the solver, Lagrangian bubbles are coupled with the continuous phase, defined on an Eulerian grid, at the sub-grid scale using volume averaging techniques. Correlations between the initial void fraction and the maximum collapse pressure in the cloud are discussed. We demonstrate acoustic imaging of the bubbles by post-processing simulated pressure signals at particular sensor locations indicating waves scattered by the clouds. Finally, we compare the simulation results with experimental results including high-speed imaging and hydrophone measurements. The time evolution of the cloud void fraction and the scattered acoustic field in the simulation agree with the experimental results. [Funding supported by NIH 2P01-DK043881.]
Thresholds for sustained bubble cloud generation in burst wave lithotripsy
Authors: Hunter Christopher , Maxwell Adam D. , Cunitz Bryan W. , Dunmire Barbrina , Kreider Wayne
Published: November 2016

Burst wave lithotripsy (BWL) is a new non-invasive approach for disintegrating kidney stones using tone bursts of sub-megahertz ultrasound. An important advantage of BWL compared to shock wave lithotripsy (SWL) is the rate at which acoustic energy can be delivered without causing cavitation that injures functional renal tissue. BWL treatments capable of breaking stones have been safely delivered to pig kidneys in vivo at a 40 Hz burst repetition frequency, representing a rate of energy delivery well in excess of that used in SWL. To facilitate the design of BWL treatments that safely and optimally break stones, this work focuses on understanding how treatment parameters affect the generation of sustained bubble clouds. High-speed photography and ultrasound imaging were used to characterize the presence and persistence of cavitation activity in vitro. Experiments were conducted for BWL treatments at 335 kHz to evaluate the impact of treatment rate, dissolved gas concentration, volumetric confinement (representing kidney collecting space), and presence/absence of a stone. Threshold pressures for generating cavitation clouds were observed to vary with each of these variables. [Funding support by NIH P01-DK043881, R01-DK092197, K01-DK104854, and NSBRI through NASA NCC 9-58.]
Parallel feedback architecture for ambisonics based active noise control
Authors: Ganguly Anshuman , Panahi Issa
Published: November 2016

Active noise control(ANC) has been widely studied for smaller acoustic cavities, like cars and small enclosures, over past several years. One of the key challenges in implementing ANC systems for larger acoustic environments lies in extending the target “quiet” zone for maximizing the noise cancellation. Traditional ANC systems use two “omnidirectional” microphones to access reference noise signal and “residual” error signal at target zone. The target zone around the error microphone remains to be small. Feedback ANC with Ambisonics is aimed to extend the quiet zone by employing specialized encoding and decoding of the noise signal accessed using a single Soundfield microphone. In this paper, a parallel Feedback ANC architecture is fused with the Ambisonics encoding to improve the noise cancellation performance. The proposed ANC system also features an adaptive signal decomposition technique to effectively handle noise types with dominant predictable components, like machinery noise. Noise attenuation level (NAL) is used to compare and quantify the advantage of the proposed method. In this paper, an attempt has been made to explore an improved ANC system for real-time noise control in larger acoustic enclosure such as museums and concert halls.
Virtual sensing technique for feedforward active noise control
Authors: Edamoto Shoma , Shi Chuang , Kajikawa Yoshinobu
Published: November 2016

Active noise control (ANC) is one of techniques to reduce unwanted acoustic noise and is based on the superposition property of acoustic waves. If an anti-noise wave is exactly generated to have the same amplitude and inverse phase of the unwanted acoustic noise wave, ANC can reduce the noise level at the desired location, where an error microphone is placed to monitor the error signal. In the case when the error microphone cannot be placed at the desired noise reduction location, virtual sensing techniques are useful. In this paper, we examine one of the virtual sensing techniques in an experiment setup using the parametric array loudspeaker as the secondary source. Experiment results show that improved noise reduction can be obtained at the virtual microphone location.
Computing the curriculum—Embedding computation in undergraduate acoustics
Authors: Wright Matthew C.
Published: November 2016

I will describe an approach to teaching acoustics to undergraduate engineering students that integrates mathematics, coding, numerical computation, and physical measurement. This approach developed and continues to develop according to my experience as Director of taught acoustical programmes at the Institute of Sound and Vibration Research (ISVR) in the Faculty of Engineering and the Environment at the University of Southampton, UK. Our program is somewhat unusual in that it teaches acoustics in depth to undergraduate students, whose understanding of the physics must develop in parallel with their proficiency in mathematical analysis and coding. I will explore how both numerical computation and coding can be integrated into an acoustics curriculum from the very start, how their inclusion can enhance learning, and how the curriculum can be restructured in order to make best use of these elements, highlighting the features of acoustics as a subject that make it particularly suited to this approach. I will also discuss how the choice of programming languages and environments, and modelling software affect the curriculum and vice versa. I will present examples from my teaching using Jupyter (formerly IPython) notebooks and discuss how to use these effectively.
Computer-based acoustics projects for audiology and speech-language pathology students
Authors: Lentz Jennifer
Published: November 2016

Graduate and undergraduate students studying audiology and speech-language pathology are often required to have a basic working knowledge of acoustics. However, convincing these students the necessity of this knowledge is a common challenge for the acoustics instructors. Consequently, motivating students to be enthusiastic about the material may be facilitated by including methods that replace or supplement traditional teaching methodologies. Computer-based projects that reinforce acoustic concepts learned in the classroom provide an outstanding hands-on opportunity to expose students to the principles of acoustics. Importantly, they also offer clear examples of how knowledge of acoustics is core to the fields of audiology and speech-language pathology. Here, I will illustrate a number of Matlab-based projects that apply acoustics to the topics of hearing, hearing loss, speech production, and speech disorders. These projects are designed to be discipline-specific and also target specifically the abilities and needs of students in audiology and speech-language pathology.
Introducing programming through acoustics and audio at Belmont University
Authors: Tarr Eric W.
Published: November 2016

A course in computer programming has been offered within the department of Audio Engineering Technology at Belmont University to provide an introduction to audio and physics students interested in learning about programming. This course is based on a foundation of acoustics and audio concepts, without requiring previous programming experience. The pedagogical approach has been to expose students to the application of programming within their discipline of interest as a motivation for further exploration. Topics in the course introduce programming concepts for specific signal processing methods. Programming concepts include: variables, operators, data types, as well as basic control structures like loops, conditional statements and functions. While learning programming concepts, students perform various signal processing methods such as: changing a signal’s amplitude, signal synthesis, stereo panning functions, mid-side processing, amplitude fades, amplitude modulation, soft/hard clipping, rectification, bit reduction, echo effects, convolution, algorithmic reverberation, expander/compressor dynamic-range processing, and various spectral filters. Course lessons for a “flipped classroom” are freely and publically available at http://www.hackaudio.com/. Since the initial offering of this course, the number of students in the audio engineering program who double-major or minor in computer science has quadrupled.
Visualization of Kansei causality for the digital piano sound—Kansei modeling for musical instruments
Authors: Tanase Rento , Sakanashi Hideki
Published: November 2016

Kansei-causality-model (structural causality model of subjective impression) for the digital piano sound and some considerations are presented. At first, the directed graph of hypothetical causality is figured from the report about the performance tests of musical instruments and the interview with the sound engineers. Second, the quantitative Kansei-data acquired by subjective test with semantic-differential method is associated with the directed graph. Then, the Kansei-causality-model are estimated from the directed graph and Kansei-data by SEM (Structural Equation Modeling) / Covariance Structural Analysis. The result suggests structurally the meanings of the words (for example “hiki-gotae (japanese)” and “high grade feeling") for the evaluation of the digital piano sound. The different causality flow represented as two passes on the structural causality model suggests the polysemy of “Noisy". Moreover, the result of CFA (Check Factor Analysis) for the same data indicates the two factors, such as must-be quality and attractive quality, in the sound engineering criterion for the digital piano design.
Sado Island: Student cultural activities—The drum performance
Authors: Morishita Shuji
Published: November 2016

Sado is an island in the Sea of Japan. The population of the island is 57,114 (October 1, 2015). Sado had a gold mine and has a rich natural environment. It was also rich economically and many people came to Sado from many other places in Japan. People brought many entertainment styles to Sado. The traditional arts are still strong, such as Noh drama and Oni-Daiko ("ogre"drum performances). We have been active in Oni-Daiko performances in Toyooka village since 2009. The festival in Toyooka is held on the first or second Sunday of April every year. It begins in the Shrine of the enshrined deity of the village. We go around the houses in the village and come back to the shrine. It is performed in front of shrines and houses. The students perform it in public at the end of their one-week lesson. We perform it from 7 a.m. to 8 p.m. with the village people. Students mature after taking part in these activities. As the population of Sado begins to decline, we do not know how long we will be able to continue this activity. However, we want to continue carrying out this activity as long as possible.
Managing matagia: Instruments and aesthetics in contemporary Tokelau performance
Authors: Steiner Candice E.
Published: November 2016

The hallmark of contemporary Tokelau performances is a significant building of energy over the course of a song and dance, which is driven by gradual tempo increases, upward key modulations, increases in volume, intensification of dance movements, and oneness among performers. The powerful pōkihi (box drum) and accompanying instruments lead the entire group through this unified move from subdued to exhilarating delivery, and when the technical skills of the performers and the cultural meanings of the performance combine in a way that fully engages the performers and audience alike, the resulting energy is palpable. In this presentation, I describe the key musical instruments used in contemporary Tokelau performances, summarize previous research on the instruments’ history and use, and discuss the role of the instruments in upholding the Tokelau aesthetics described above.
Construction and modernization of Kundun Pentatonic xylophone
Authors: Kemewerigha Tobi E. , Onwubiko Stephen G.
Published: November 2016

This thesis is all about the constructional techniques and modernization of the resonant qualities of Kundun musical instrument from Birom in Plateau State of Nigeria. A discussion of the traditional Xylophone based on the field work conducted in Birom ethnic group understanding a kundun instrument maker, was made. The structure of this Xylophone highlights both the tone qualities and also the use of the cow-horn as pipes which amplifies the resonance of the slab. The construction and methods used here embodied traditional technology together with modern innovations, with the aim of improving the tone and aesthetic qualities of the instrument. This report also offered guides on the correct choice of wood and other materials for construction. Special attention was given to the acoustic behavior of kundun and the particular problems of the tropical climate conditions, to which the instrument could be exposed and to the overall tone quality of the instrument during performance. Some scientific approaches, in terms of the accurate measurements and amplification of sound, were taken into cognizance so as to enhance the knowledge of the construction of kundun musical instruments and its aesthetic quality.
Experimental contribution analysis of external noise components to interior noise of automobile
Authors: Hwang Seongil , Lee Myunghan , Ih Kang Duck , Kim Yong-Joe
Published: November 2016

The contribution analysis of various noise sources to interior noise is important, enabling to design an automobile with a low interior noise level. Here, using a modified Cholesky Decomposition (CD), it is proposed to decompose interior noise spectra into multiple spectra, each represents the contribution of a specific noise source to the interior noise. Through an experiment with the two speakers driven by two independent white noise signals, it is shown that the measured noise spectrum can successfully be decomposed into two contributions, each associated with noise radiated from one of the two speakers. Then, an automobile was tested on a road at the speeds of 65 mph and 80 mph. In this experiment, 64 external and 4 interior microphones were used to measure external noise source signals and interior noise signals, respectively. The contribution results obtained by processing the measured microphone signals show the highest contributions of the aeroacoustic sources on the windows and the hood to the interior noise. It was also observed that the contribution of the windows increased as the speed increased and that the higher contribution to the interior noise at a specific seat could be obtained from the window closer to the seat.
Noise produced within spaces adjacent to high performance jet operations on large amphibious assault ships
Authors: Hughes Ronald , Antonides Steven , Kannepalli Chandrasekhar
Published: November 2016

Airborne noise levels have been measured in spaces adjacent to F-35B operations in proximity to the flight deck on Large Amphibious Assault Class ships (L Class). Noise levels observed in some manned spaces are hearing hazardous. The noise produced during high performance jet operations is intermittent to steady state in duration. Results reported here are only for vertical landings (VL) and do not include short takeoffs (STO); however, noise due to both VL and STO exhibit similar characteristics. Observed VL noise features include two prominent types of noise sources during aircraft decent as well as source directionality. These features are compared to LES CFD predictions for a supersonic jet impinging on a plate. Qualitative features observed in data have been included in a noise model to predict noise levels in Gallery deck compartments. Predicted noise levels are used to ascertain noise treatments and hearing protection on L Class ships during F-35B air operations. Motivations for controlling noise levels are to prevent or reduce hearing threshold shifts in crew members and to promote hearing recovery and communication intelligibility. Noise characteristics of F-35B landings and diagrams of predicted noise levels that address noise-induced hearing loss, hearing recovery, and communication intelligibility are shown.
Numerical Simulation of time domain wall impedance on circular and annular ducts using the immersed boundary method
Authors: Gutierrez Pimenta Braulio , Maldonado Ana Luisa P. , Bobenrieth Miserda Roberto F.
Published: November 2016

In this work, time domain boundary conditions of wall impedance are simulated on circular and annular ducts of constant cross section. The discretization technique used here is the immersed boundary method in the framework of finite volume formulation. It has fourth order of precision in space and uses a third order Runge-Kutta method for time stepping. Several boundary conditions for wall impedance are tested and then compared with the analytical results of the one-dimensional resonating chamber for code validation. The impedance boundary conditions are simulated on a circular duct with wall treatment and with a synthetic sound source. Mean flow conditions include constant axial velocity and swirling flows of rigid body rotation and potential flow. The results are then compared with a fourth order eigensystem method of linearized governing equations. The results of the immersed boundary methodology are assessed along with the wall impedance boundary condition models and their linear validity is compared with the results of the eigensystem method.
Case report of a low-frequency noise complaint settled through adjudication by the Environmental Dispute Coordination Commission
Authors: Takahashi Yukio
Published: November 2016

In Japan, complaints about environmental low-frequency noise have been increasing in recent 20 years. The Environmental Dispute Coordination Commission is a subsection of the Ministry of Internal Affairs and Communications and one of its main duties is to resolve environmental disputes promptly and appropriately through adjudication, mediation, and other ways. The Commission treats some cases of complaint about low-frequency noise every year. This presentation outlines the activity of the Commission and reports a case of a low-frequency noise complaint settled through adjudication by the Commission. The author took part in the adjudicating process as an external technical expert, and supported on-site measurement of the noise and evaluation of its effect. The source of the noise in the case was air compressors located at a supermarket adjacent to the complainant’s house. In evaluating the effect of the noise, much importance was given not to merely the sound pressure level of the noise but to the correspondence between the sound pressure level of the noise and subjective ratings of the complainant’s annoyance. Thanks to a good correspondence found between them, the complainant and the supermarket arrived at compromise.
Psychological and physiological response of low frequency noise of ordinary persons and complainants
Authors: Yamada Shinji , Inukai Yukio , Sebayashi Tsutae , Kitamura Toshiya
Published: November 2016

In Japan, there are some complainants of low frequency noise. There are two sorts of complains on low frequency noise. One complain is the phenomenon of rattling noise. Light windows or doors are vibrated and rattled by the pressure of low frequency noise. Sound sources are a big diesel engine, pass by of a heavy truck on a highway bridge, a gas turbine engine generator etc. The other complaints are the direct hearing or detection of low frequency noise. Sound sources are a boiler, a cooling tower, etc., near neighbors, or solid borne noise inside a room. But recently, there are some complains at very low level and the sound source cannot be detected. In these cases, there may be much influences by mass media and Internet knowledge. In this paper we explain the mechanism of complains on low frequency noise as bellows. Hearing thresholds of ordinary persons and complainants. Physiological response of ordinary persons and complainants. Time history of annoyance of complainants according to on-and-off of sound source. Recent complains against low frequency noise. Guideline on low frequency noise: Mechanism of complaint in brain to wind turbine low frequency noise.
Nonclassical nonlinearity and crystal defects in lithium niobate
Authors: Chatterjee Chandrima , Cremaldi Lucien , Ostrovskii Igor
Published: November 2016

Nonclassical nonlinearity (NN) in ultrasound attenuation and acoustic memory in LiNbO3.may be connected to crystal defects. The optical spectra of photoluminescence (PL) and absorption taken from 350—900 nm reveal multiple point defects and impurities such as F-center, NbLi+, Fe, Ba, Ar, Xe and others. The spectra are taken at room temperature from the Czochralski grown bulk crystals and wafers. The samples are scanned by taking PL spectra from different locations along the z- and y-axes. The data from several samples reveal a nonuniform distribution of the defects along the crystallographic axes. The dependencies of PL peaks versus position have a sine-like component on top of some constant intensity. For instance, a scan for F-center has a period (P) from 0.27 to 0.75 mm and for Ba impurity from 0.25 to 0.75 mm in bulk crystals. In the wafers, P may be smaller, that is 0.1 mm and smaller. However, a ratio of maxima to minima in PL peaks is higher for bigger P. The overall spread of P is roughly from < 0.1 mm to about 1 mm. Some defects are electrically charged, and may influence the piezoelectric properties. Consequently, a real crystal has some constants which are nonuniform along its axes. The measured periods P correspond to ultrasonic wavelengths in the Megahertz frequency range. The comparison of the periods P in defects distributions with the frequencies of NN phenomena points to considering crystalline defects as those responsible for the NN observed in LiNbO3.
Ultrasonic array imaging of contact-acoustic nonlinearity
Authors: Potter Jack , Chen Jingwei , Drinkwater Bruce , Croxford Anthony
Published: November 2016

Classically, ultrasonic arrays achieved physical beam-forming through the application of phase delays to the parallel transmission of elements. Alternatively, beam-forming may be emulated through post-processing of sequentially transmitted array data. Though exactly equivalent for linear systems, these parallel and sequential fields differ in their nonlinear propagation. Information pertaining to elastic nonlinearity is encoded onto the relative parallel/sequential field by interference between the field components of individual element transmissions. A family of nonlinear imaging techniques has been developed which exploit differences between parallel and sequential fields in order to image elastic nonlinearity. Diffuse energy and coherent scattering variants of the technique are demonstrated for the imaging and characterisation of contact-acoustic nonlinearity in application to the detection and sizing of closed fatigue cracks.
Evaluation of fatigue damage in a pure copper with nonlinear three-wave interaction
Authors: Ishii Yutaka , Ohtani Toshihiro , Nakaniwa Masayoshi , Kamaya Masayuki
Published: November 2016

We investigated nonlinear ultrasonic characterization, nonlinear three-wave interaction, of the pure copper during fatigue with EMAR (Electromagnetic Acoustic Resonance), which was the combination with ultrasonic resonance and non-contacting transducer, EMAT (Electromagnetic Acoustic Transducer). In nonlinear three-wave interaction method, two intersecting ultrasonic waves produced a scattered wave when the resonance condition was satisfied. The amplitude in resonant scattering wave was measured. Nonlinear three-wave interaction method exhibited high sensitivity to micro-structural change of the damaged material. It rapidly increased from 50% of fatigue life to the fracture. TEM (Transmission Electron Microscope) and EBSD (Electron Backscatter Diffraction) observations supported this phenomenon caused by dislocation movement. The sensitivity in three-wave interaction method was higher than that in linear methods. The noncontact resonance-EMAT measurement can monitor the evolution of nonlinearity throughout the fatigue life and has a potential to assess the damage advance and to predict the fatigue life of metals.