bluuebunny/crossref_metadata_2025 huggingface dataset:
Riding the wave: Scale-dependent descriptions of walleye pollock distributions
Authors: Burgos Julian M. , Horne John K. , Horne John K.
Published: October 2013

Wavelet analysis was used to describe scale-dependent distributional variability of walleye pollock (Theragra chalcogramma) in the eastern Bering Sea shelf between 2000 and 2002. Area backscattering strength (ABC), a measure of acoustic density, was calculated at 20-m horizontal intervals in five echo-integration trawl surveys. The maximum overlap discrete wavelet transform was used to partition the ABC variance into scales ranging from 0.04 to 10.24 km. Wavelet variance was estimated for each transect after denoising with phase plane thresholding. Wavelet spectra can be characterized by large variances at small scales (less than 0.64 km), decreasing when scale increased to 1.28 km, and increasing variance at larger scales. The fraction of the total variance assigned to small scales was negatively correlated with the total acoustic density. This is attributed to the aggregative behavior of walleye pollock. Peaks in wavelet spectra, indicating the presence of coherent features (i.e., schools or shoals), were observed in 48% of the transects at scales ranging from 1.28 to 10.24 km. Peaks at larger scales were more common in winter transects, when walleye pollock form large spawning aggregations.
Combining acoustics and video to image fish in the acoustic dead zone
Authors: Miksis-Olds Jennifer L. , Bernard Ernest , Jakubiak Christopher J. , Holliday D. V.
Published: October 2013

A stationary acoustical-optical platform (AOP) has been developed to detect groundfish presence and to estimate biomass. The AOP is a new approach to fisheries science because sampling from a platform on the ocean floor overcomes limitations of traditional surface acoustic surveys, where echoes from groundfish near the seafloor are obscured by stronger reflections from the ocean bottom. The AOP capitalizes on the complementary strengths of acoustical and optical sampling techniques by using acoustics for fish enumeration and optics for species identification and measurements of fish length. Each AOP is equipped with four video cameras, two 200-kHz sonar transducers, and a suite of environmental sensors. One sonar face is mounted in the horizontal direction to image the area directly above the seafloor, whereas the second transducer is oriented vertically to sample the water column above the platform. Acoustic backscatter, target species, size, and observation angle were quantified when fish were simultaneously detected by the sonar and optical sensors. Calculations of target strengths were then related to fish size and orientation, for incorporation into biomass estimates. The AOP is designed to be used in an observation system with multiple platforms elements, so fish populations can be monitored over large spatial scales. [Work supported by NOAA.]
Comparing acoustic model estimations and in situ target strength measurements of juvenile walleye pollock (Theragra chalcogramma)
Authors: Sadayasu Kazuhiro , Mukai Tohru , Iida Kohji
Published: October 2013

Recently, many acoustic surveys for the juvenile walleye pollock have been done around the Hokkaido, Japan. Dependence of target strength on fish length is a most important factor in the conversion of acoustic data to fish biomass. However, the relation between target strength and length of juvenile walleye pollock is not well investigated. This study examined the target strength length relationship (3–10 cm) for the echo integration measurements of the juvenile walleye pollock at 38 kHz from acoustic theoretical model predictions and in situ measurements. A prolate spheroid model was used to compute the target strength of the fish relative to its orientation. Swimbladder morphologies of live juvenile walleye pollock caught by set net were obtained from transmission of light or soft x-ray, and converted their morphological parameters. Biological samplings using framed mid-water trawl were carried out near the spawning area of walleye pollock. During fish samplings, in situ target strength measurements were conducted using quantitative echo sounder with split beam transducer. While predicted mean target strengths matched mean in situ measurements at small length, there was not agreement at the large length. This discrepancy is a result of avoidance of large fishes from a net mouth.
Moving ship thermometry
Authors: Mercer James A. , Alger Nick , Howe Bruce M. , Andrew Rex K. , Colosi John A.
Published: October 2013

The long-range ocean acoustic propagation experiment (LOAPEX), conducted in the NE Pacific Ocean, provided acoustic transmissions from a ship-suspended source at seven stations spanning a near zonal path of 3200 km. The transmissions were received on several bottom-mounted horizontal hydrophone arrays distributed about the NE Pacific Ocean Basin. The experiment and a simple inverse method are described and a preliminary thermal ‘‘snapshot’’ of the ocean basin is presented. [Work supported by ONR.]
Anisotropy in the spatial distribution of the arrival points of a ray after a fixed travel time
Authors: Flatté Stanley M. , Colosi John A.
Published: October 2013

An acoustic pulse emitted from a point source arrives on a well-defined wavefront after a fixed travel time. In the geometrical-acoustics approximation, this behavior is understood by following rays. Two simple ray models are presented to treat the scattering of rays by internal waves, and to evaluate the ratio of movements in the ray end points within and perpendicular to the wavefront. Assuming weak forward scattering, and no waveguide, the model predicts that the end points move along the wavefront over much larger distances than perpendicular to the wavefront. [Work supported by ONR.]
Fresnel zones in inhomogeneous media
Authors: Rypina Irina I. , Brown Michael G.
Published: October 2013

A simple general expression for the width of a Fresnel zone in a smooth inhomogeneous environment is derived. In a stratified environment at long range, the general expression is shown to reduce approximately to one that is proportional to √|α|r(R−r)/f, where α is the ray stability parameter, f is the acoustic frequency, r is the range to the field point of interest, and R is the source-to-receiver range. In a stratified environment on which a weak perturbation is superimposed, at long range the width of a bundle of micromultipaths is shown to be approximately proportional to |α|√r(R−r). Thus, at long range both the diffractive and scattering contributions to ‘‘the width of a ray’’ are proportional to √r(R−r) and increase with increasing |α|. Theoretical predictions are shown to agree well with travel time sensitivity kernel calculations. [Work supported by ONR.]
Moving ship tomography from the Basin Acoustic Seamount Scattering Experiment (BASSEX-04)
Authors: Heaney Kevin D. , Baggeroer Arthur B. , Worcester Peter F. , Dzieciuch Matthew A.
Published: October 2013

During the Basin Acoustic Seamount Scattering EXperiment (BASSEX-2004) a set of 32 acoustic transmissions of four moored sources in the central Pacific were made. Broadband transmissions (100 Hz bandwidth, 250 Hz center frequency, 12.276 s period length) from two sources suspended (800 m depth) were received on a towed array (350 m depth, 200 m aperture) as it passed between the two sources at a range of 250 km. This data set provides the opportunity for examining the feasibility of underway moving ship tomography (MST). The primary oceanographic feature is the variability of the mixed layer over a 500×500-km2 region. Accurate ocean acoustic tomography requires the development of an N×2D inversion scheme as well as techniques to perform array element localization to within 10 m. Results on applying a Kalman-filter-based technique to the array sensor data (depth, pitch, roll) and the measured ADCP will be presented. With the receiving ship transecting the path between the two source moorings, each transmission has two paths that pass through different bodies of water.
Vertical coherence of low-frequency sound waves propagating through a fluctuating ocean
Authors: Voronovich Alexander G. , Ostashev Vladimir E.
Published: October 2013

Low-frequency sound waves propagating over large distances in the ocean exhibit significant scattering due to internal waves. Studies of low-frequency sound propagation through a fluctuating ocean are important for many practical concerns such as communication, acoustic tomography, and source detection, ranging, and recognition. In a recent work [A. G. Voronovich and V. E. Ostashev, J. Acoust. Soc. Am. 63, 1406–1419 (2006)] a 3-D modal theory of sound propagation through a fluctuating ocean was developed. Closed equations for the first two statistical moments of a sound field were derived using the Chernov method and assuming that the spectrum of internal waves is given by the Garret-Munk spectrum. In the present paper, we numerically solve the derived equation for the second moment. The results obtained are used to study the dependence of the vertical coherence of a sound field on several parameters of the problem: range, frequency, source and receiver depths, and parameters that characterize the Garret-Munk spectrum. [Work supported by ONR.]
Evolution of a downslope propagating acoustic pulse
Authors: Heaney Kevin D. , Baggeroer Arthur B. , Worcester Peter F. , Dzieciuch Matthew A. , Mercer James A. , Howe Bruce M. , Andrew Rex K.
Published: October 2013

During the North Pacific Acoustics Laboratory (NPAL-04) experiment broadband transmissions (50 Hz bandwidth, 75 Hz center frequency, 27.28 s period length) from a bottom-mounted source off the island of Kauai were received on a towed array (350 m depth, 200 m aperture) near the island and a large aperture vertical line array (VLA) at a range of 2469.5 km. Previous work [Heaney, J. Acoust. Soc. Am. 117(3), 1635–1642 (2005)] has demonstrated that bottom interaction near the source is a fundamental process in the evolution of the wave-train. In this paper results from eight receptions at ranges from 2 to 300 km and the reception on the distant VLA is used to examine the wavefront evolution as it propagates into deep water. Results from a local geo-acoustic inversion will be presented as well as comparison of data with broadband parabolic equation simulations. The initial conclusion is that the first-order bottom bounce, off the seamount near the source, acts as an image source, contributing to a complex arrival pattern even at great distances.
Evolution of second-order statistics of low-order acoustic modes
Authors: Chandrayadula Tarun K. , Wage Kathleen E. , Mercer James A. , Howe Bruce M. , Andrew Rex K. , Worcester Peter F. , Dzieciuch Matthew A.
Published: October 2013

Low-mode signals measured during long range tomography experiments, such as the Acoustic Thermometry of Ocean Climate (ATOC) and the North Pacific Acoustic Laboratory experiments, have a random arrival structure due to internal waves. At megameter ranges, the narrow-band mode amplitude is predicted to be Gaussian and uncorrelated with other modes [Dozier and Tappert, J. Acoust. Soc. Am. 63, 353–365 (1978)]. Wage et al. measured the centroid, frequency coherence, time spread, and time coherence for the broadband ATOC mode signals received at ranges exceeding 3000 km [Wage et al., J. Acoust. Soc. Am. 117, 1565–1581 (2005)]. The 2004 Long Range Acoustic Propagation EXperiment (LOAPEX) provided an opportunity to observe how the mode statistics evolves with range. This talk investigates the mean, temporal covariance, and intermodal correlation of the low modes at ranges between 50 and 3200 km using LOAPEX data. Broadband parabolic equation simulations were performed to model internal wave effects on the low-mode signals at the various LOAPEX stations. A kurtosis measure is used to study the amount of cross-modal scattering with respect to range. Statistics of the measured and simulated mode signals are compared. [Work supported by ONR.]
A comparison of experimental and theoretical forward scattering by the Kermit-Roosevelt Seamount
Authors: Baggeroer Arthur , Schmidt Henrik , Sikora Joseph , Kim Hyun Joe , Scheer Edward , Worcester Peter F. , Dzieciuch Matthew A. , Heaney Kevin D.
Published: October 2013

The SPICEX-LOAPEX-BASSEX experiments measured forward scattering from the Kermit-Roosevelt seamounts. LFM and M-sequence signals from 250-Hz moored sources and a 75-Hz ship-deployed source were received with Penn State University’s 162-element FORA array. Receptions were obtained from these sources at ranges of hundreds to 1600 km. Previous work [J. Acoust. Soc. Am. 117, (2549)] discussed the BASSEX forward shadow and patterns of horizontal refraction around the seamount. Additional work [J. Acoust. Soc. Am. 118, (1936)] compared experimental results with theory using a conical section model of a seamount. This presentation concerns the pulse compressed and array processed time series of M-sequence signals in the forward scattered field of the seamounts. Both travel times and angles of arrival are reconciled with 2-D ray-trace models. Results are comparable to refracted rays, which mainly propagate over the seamount. These, however, do not explain additional echoes, which appear in the experiment, possibly due to reflection and/or diffraction. Normal mode and PE methods are used to confirm ray models and identify additional echoes.
Extracorporeal cardiac shock wave therapy ameliorates myocardial ischemia in animals and humans
Authors: Shimokawa Hiroaki
Published: October 2013

The number of patients with end-stage coronary artery disease without indication of coronary intervention or coronary artery bypass surgery has been increasing. Gene and/or cell angiogenic therapies are currently under investigation for those patients, however, the therapies are invasive in nature and their effectiveness and safety have not been established yet. We here report our successful development of noninvasive extracorporeal cardiac shock wave therapy (CSWT) for the treatment of myocardial ischemia. We first confirmed that endothelial expression of VEGF and its receptor Flt-1 peaks with a low level of SW at 0.09 mJ/mm2 in vitro. We then demonstrated that CSWT effectively ameliorates myocardial ischemia in a porcine model of effort angina without any adverse effects. Finally, we were able to demonstrate that CSWT effectively ameliorates myocardial ischemia and related symptoms in patients with end-stage coronary artery disease without any adverse effects. Myocardial perfusion was improved with CSWT only in the ischemic region where we treated with the therapy. We are currently performing a double-blind clinical study to further confirm the usefulness and safety of our CSWT. [Work supported in part by grants from the Japanese Ministry of Health, Labor and Welfare.]
Shock waves in orthopedics
Authors: Saisu Takashi
Published: October 2013

Extracorporeal shock wave therapy (ESWT) in the orthopedic field was first reported in 1991 by Valchanou, for the treatment of pseudoarthrosis after fracture. Since 1995, many authors have reported on ESWT for the treatment of painful disease such as calcifying tendinitis of the shoulder, tennis elbow, or planter fasciitis. Now, it has become one of the major treatment methods in orthopedics and veterinary medicine, especially for racehorses. The shock wave research group at Chiba University has been studying ESWT since 1993. We have been elucidating mechanisms of action to the bone and the neural system, performing basic studies using rabbits and rats. A shock wave has three different effects, which are bone induction after multifocal microfracture, perforation of calcified tissue, and induction of degeneration of free nerve ending. Each effect has been utilized for the treatment of pseudoarthrosis, calcifying tendinitis of the shoulder, and enthesopathy such as tennis elbow or planter fasciitis, respectively. Considering our experiences in animal studies, future applications of ESWT would be noninvasive thickening and lengthening of bone and nonsurgical acetabular plasty to prevent osteoarthritis of the hip. Recently, we have been trying nonviral gene transfer assisted by shock waves and we have succeeded in a preliminary animal study.
The effects of plane shock wave on the endothelial cells in vitro and the numerical analysis of pressure wave in the cell
Authors: Tamagawa Masaaki , Iwakura Seiya , Suetsugu Shiro , Fujii Jun
Published: October 2013

Shock wave phenomena in living tissues are being applied in the fields of tissue engineering. It is expected that the elastic cells such as endothelial cells and cardio cells have a potential to regenerate or grow quickly by using high pressure wave and short duration time from 1 μs to 100 ms. There are two mechanisms for this, one is the effect of shock waves and the other is the effect of cavitation bubbles. In this paper, to investigate only the effects of plane shock waves on the endothelial cells in vitro, the cells worked by shock waves are observed by microscope, and FEM numerical simulation is done to analyze the mechanism. For experiments, the shock tube apparatus is used that makes plane waves and has several tens of ms duration time. After working shock waves (peak pressure 0.4 MPa) on suspended cells, 10% of them are disintegrated, but the others increase faster than control cells in vitro. The growth of cells by plane shock waves is also confirmed by the fact that activated gene expression is enhanced. Numerical simulation results show the gradient of the shear stress wave is an important factor.
Experimental application of Holmium:yttrium-aluminum-garnet laser-induced shock wave as a drug delivery system
Authors: Ohki Tomohiro , Hosseini S. H. R. , Takayama Kazuyoshi , Sato Junichi , Nakagawa Atsuhiro , Tominaga Teiji , Kambe Mariko , Sun Mingu
Published: October 2013

One of the possible applications of shock waves is enhancement of drug delivery in the central nervous system. To achieve such a goal, it is necessary to develop a suitable shock wave source with the ability to be integrated with an endoscope or a catheter. We have developed a shock wave generator using a pulsed Ho:YAG laser as the energy source; this device is remarkable for its ability to expose shock wave to target tissue in a localized area. The physical feature and characteristics of the generator were clarified. The overpressures of Ho:YAG laser-induced cavitational shock waves were measured by using a PVDF needle hydrophone. Maximum overpressure of 19 MPa at 4-mm distance from tip of the device was obtained. As a preliminary experiment, the device was applied to evaluate the enhancement of chemotherapeutic effects of shock wave in vitro, using human gastric cancer cell (GCIY cell) line and an anticancer drug (Bleomycin: BLM). Proliferation rate of the cells decreased to 90% and 45%, after application of 4000 and 6000 shots of shock waves at the BLM concentration of 1 mic-g/ml. Inhibitions in proliferation rate were observed in accordance with the number of shock wave applications and BLM concentrations.
Photo-elastic, high-speed images of stress induced in cylindrical model kidney stones by lithotripsy
Authors: MacConaghy Brian , Ikeda Teiichiro , Bailey Michael R. , Maxwell Adam D. , Sapozhnikov Oleg A.
Published: October 2013

Recent experiments and calculations show that a focusing shear wave generated by the shock wave traveling along the length of a cylindrical stone creates the dominant stress and causes fracture of cylindrical model stones. A small disk placed on the proximal face of the stone suppressed the longitudinal wave responsible for spallation in calculations yet had little effect on the number of shock waves required to fracture the stone in experiment. However, a disk placed around the stone blocked the shock wave traveling along the stone in calculations and suppressed fracture in measurements. The conclusion was that so-called dynamic squeezing was a dominant mechanism to spallation. Here, photo-elastic, high-speed imaging was used to observe the suppression of various waves in cylindrical stones made of acrylic. Glycerol was used to avoid artifact from the curvature of the stone. Comparison was made to calculations using the elasticity equations for an isotropic medium. Agreement between measurement and calculation was excellent and supports dynamic squeezing. The results help validate the model, and the technique and modeling may help us understand where and how stress is created in other shock wave therapies. [Work supported by NIH DK43881 and NSBRI SMS00402.]
Ultrasonic motors—breakthrough trials for the next generation
Authors: Tomikawa Yoshiro , Kusakabe Chiharu , Tamura Hideki , Hirose Seiji , Takano Takehiro , Aoyagi Manabu
Published: October 2013

Twenty years and more have passed since real research of ultrasonic motors was started and now their practical applications are performed in some engineering fields. Therefore, such a problem has happened now as to what kinds of breakthrough ultrasonic motors must be researched for the next generation. For this reason, we are challenging the breakthrough research of the ultrasonic motors. This paper deals with such breakthrough motors. In the first part, we deal with thin-form ultrasonic motors of high revolution speed for their use as HDD motors, applying lead-free piezoelectric single crystal of LiNbO3. The second part contains some gyro-moment motors, devised by us originally. The motors can be driven electromagnetically and, moreover, electrostatically in theory. Therefore the motors are suited to ones fabricated by MEMS technology and might be applied as a micro-fun motor for heat radiation in electronic apparatuses, a windmill motor in fuel cells, and so on.
Modeling and performance evaluation of an ultrasonic pump
Authors: Hasegawa Takeshi , Koyama Daisuke , Nakamura Kentaro , Ueha Sadayuki
Published: October 2013

This paper describes a low-profile miniature ultrasonic pump consisting of a disk-bending vibrator and a pipe-end located vertically to the disk center via a small gap. First, we explored the relationships between the pump performance and the geometrical conditions of the pump experimentally: the pipe diameter, the gap, and vibration distributions. Based on those results, the thickness distribution of the bending disk was designed using finite-element simulations so that the vibration distribution near the pipe might become uniform. Maximum pump pressure of 20.6 kPa was obtained with a 30-mm-diam bending disk and electrical power consumption of 3.8 W. For optimization, we constructed a model of the pump operation in this study. Nonlinearity in the elastic constant of the working fluid was introduced into the model because the temporal change rate of the gap caused by the ultrasonic vibration of the disk vibrator considerably affects the pump’s pressure generation. Results show that the calculated pump pressure well simulates the measured dependence of the gap on the pressure. The acoustic pressure was measured using a fiber optic pressure probe and was compared to the calculated pressure value.
The TDK model for micromachined capacitive Lamb wave transducers
Authors: Ge Li-Feng
Published: October 2013

Electrostatic or capacitive ultrasonic transducers (EUTs or CUTs) were originally developed from the condenser transmitters and microphones with grooved and roughened backplates in the 1930s. Significant progress in theoretical and experimental research has been made since the introduction of micromachining techniques at the end of the 1980s. We have seen the advancement not only from the roughened ultrasonic transducers to the 2-D array micromachined capacitive ultrasonic transducers (mCUTs), but also from the grooved ultrasonic transducers to the micromachined capacitive Lamb wave transducers (mCLWTs). Thus, the theoretical TDK model originally developed for grooved ultrasonic transducers [L.-F. Ge, Proceedings 16th Intl. Conf. Acoustics/135th ASA Meeting, l08l–1082, 1998; and Sciences in China (A), (in English), 42, 1308–1315 (1999)] can be used for mCLWTs. It is most important for a reliable model to be able to predict the transducer’s natural frequencies, at which the lowest-order antisymmetric Lamb wave (A0 wave) is excited. As an example using a typical transducer [M. H. Badi et al., IEEE Trans. Ultrason. Ferroelectr. Freq. Control 50(9), 1191–1203 (2003)], the fundamental frequency predicted using the TDK model is 2.18 MHz, which agrees well with the measured result of 2.1 MHz. [Work supported by NSFC (60374044).]
Animations of different sound field decomposition methods
Authors: Svensson U. Peter , Sto/fringsdal Bård
Published: October 2013

Many methods for solving sound-wave propagation problems are based on a decomposition of the sound field. Here, several such decomposition methods will be demonstrated and it will be illustrated how they can give the same final solution even if the partial solutions, or the solutions outside a limited domain, can be very different. Animations of harmonic and transient solutions will be used to illustrate sound-field synthesis based on a decomposition into plane waves, cylindrical harmonics, and geometrical acoustics plus edge-diffraction components. It will also be shown how a sound field that is measured in discrete points can be converted to different representations. These decompositions have pedagogical merits but can also be used in sound-field reproduction techniques. Examples will include free-field situations as well as indoor cases with a multitude of reflections. [This research was supported by the Research Council of Norway.]
An integrated system for learning musical theories from western classical and popular music
Authors: Miura Masanobu , Emura Norio , Yanagida Masuzo
Published: October 2013

Presented here is a support system for learning the theory of harmony, one of the main subjects in music education consisting of a set of forbidden progressions. By solving given tasks in the theory of harmony, students can learn forbidden progressions. Shown here is a system that generates all the allowable solutions for given bass tasks within triads, named ‘‘BDS’’ (Basse Donnée system), together with a checking system for answers given by students, named ‘‘VISAGE’’ (Validity Inspecting System for Answers of Given Exercises). VISAGE is designed to point out note allocations that violate forbidden progressions in an input answer if any. In case an answer of a given exercise does not violate forbidden progressions, the input answer is evaluated from a viewpoint of music. Also presented is ‘‘MAESTRO’’ (Musical Aesthetics Evaluation System for Tonal music in Regular and Orthodox style), which evaluates aesthetics of answers to given base tasks. [Work partly supported by Grant-in-Aid for Scientific Research (No. 16700154), MEXT, by High-tech Research Center promoted by Ryukoku University, by Academic Frontier Project promoted by Doshisha University, and by Knowledge Cluster Project promoted by MEXT, Japan.]
Acoustic demonstrations for education in speech science
Authors: Arai Takayuki
Published: October 2013

Acoustic demonstrations are highly effective for education in speech science. We recently developed two educational tools for acoustics. The first educational tool is a set of physical models of the human vocal tract and related models. It contains cylinder and plate-type models [T. Arai, J. Phonetic Soc. Jpn., 5(2), 31–38 (2001)], a sliding three-tube model [T. Arai, Acoust. Sci. Technol., to be published], lung models, an artificial larynx, and head-shaped models [T. Arai, Acoust. Sci. Technol., 27(2), 111–113 (2006)]. Each model has its own advantages and, if combined effectively, can produce a systematic and comprehensive education in speech production from the lungs to the head. The second educational tool is ‘‘Digital Pattern Playback (DPP)’’ [T. Arai et al., Acoust. Sci. Tech., to be published], which converts a spectrographic image of a speech signal back to sound by digital signal processing. A printed spectrogram on a sheet of paper can also be converted immediately after capturing the image from a camera, and we confirmed that this is more intuitive for learners than converting from an electronic image. [Work partially supported by JSPS.KAKENHI (17500603).]
Wonders in perception and manipulation of speech
Authors: Kashino Makio , Kawahara Hideki , Riquimaroux Hiroshi
Published: October 2013

Under certain conditions, the auditory system can display a number of amazing behaviors. Some of these can be quite unique and may have significant importance for our understanding of the perception of sound. This presentation focuses on behaviors closely related to speech perception. One phenomenon that will be described is termed phonemic restoration. In it, sounds actually missing from a speech signal can be synthesized by the auditory system and clearly heard. Another phenomenon involves noise vocoded speech. In it, speech remains highly intelligible despite the fact that much of its spectral detail is absent. Audio demonstrations will be provided so that the phenomena can be directly experienced. Studying these phenomena will help us understand the function of the central auditory system and develop improved techniques for speech recognition and speech synthesis. This presentation will also contain a demonstration of STRAIGHT, a versatile tool allowing manipulation of various aspects of the speech signal. These demonstrations may be of interest not only to students, but also to teachers in physiology, psychology, and engineering.
Inexpensive demonstration experiments in acoustics
Authors: Morrison Andrew , Rossing Thomas
Published: October 2013

We describe and demonstrate simple classroom demonstration experiments in acoustics using inexpensive equipment.
A MIDI (musical instrument digital interface) controller using a mat switch operable by a user in a wheelchair
Authors: Niikawa Takuya , Kawachi Ryosuke , Minato Kotaro , Yoshihara Tatsuo , Terayama Naoya
Published: October 2013

In this study, we devised a MIDI controller that a user with severe physical dysfunction was able to operate by depressing a mat switch with an electric wheelchair, and proposed a new method for musical education and therapy employing the system. This system comprises a mat switch resistant to 100 N of a movement load in a 500×700 mm2 area, an A/D converter, a PC, and a MIDI device. Signal output from the mat switch is converted to MIDI signals by the PC and transmitted to the MIDI device. By pushing down ten mat switches arranged in a matrix pattern, a user can manipulate all elements necessary to control MIDI signals, such as volume and musical sounds. As a result, it was confirmed that a user in an electric wheelchair was able to control musical notes, volume, tunes, and scales. Furthermore, since it was possible to use it for a hand bell and a musical game mimicking the card game ‘‘Concentration,’’ it may be applicable for musical education.
Sound production in Asian and Western free-reed instruments
Authors: Cottingham James P.
Published: October 2013

There are two families of free-reed instruments. This paper summarizes some of the research on both done in recent years, with emphasis on differences in history and means of sound production. The Asian mouth-blown instruments are of ancient origin and use a free reed coupled to a pipe resonator. The sheng, sho, khaen, and bawu are typical examples. These reeds are approximately symmetric, typically cut from a single strip of material, and often operate on both directions of air flow. They behave as blown-open or outward-striking reeds, with playing frequency above both the resonant frequency of the pipe and the natural frequency of the reed. The Western free-reed family originated in Europe about 200 years ago and includes the reed organ, harmonium, harmonica, and the accordion-concertina family. In these the reed tongue is offset from the opening in the frame. This permits operation on only one direction of air flow, and pipe resonators are not required and generally not used. The playing frequency of the air-driven reeds is normally below the natural reed frequency and, if the reed is coupled with a pipe, below the resonant frequency of the pipe as well.
Cross-cultural comparison of flute acoustics and playing techniques
Authors: Hoekje Peter L. , Eustache Pedro
Published: October 2013

Examples of flutes from different cultures around the world will be demonstrated, including European flutes, Persian ney, Egyptian kawala, traditional Indian bansuri, custom King bansuri, Japanese shakuhachi, Chinese di, South American kena, and Polynesian nose flutes. The differences among these may in large part be classified according to the details of their sound production mechanism at the mouthpiece, and of the bore and toneholes that form the resonator. These features are closely linked with the sound of the instrument as well as the notes and music played on it, and the playing techniques and styles developed for it. A cross-cultural problem arises when a musician needs to play with the sound and style of a non-Western flute tradition in the context of Western instruments and music. Various solutions to this problem, involving adaptation of either the mouthpiece or the resonator, have been developed.
Sonic-boom research activities in the Japan Aerospace Exploration Agency (JAXA)
Authors: Makino Yoshikazu
Published: October 2013

Some sonic-boom research activities conducted in the Japan Aerospace Exploration Agency (JAXA) are summarized. JAXA started a scaled supersonic experimental airplane program named NEXST-1 in 1996 in order to establish advanced CFD-based design technologies. The flight test of the NEXST-1 was conducted in October, 2005 at Woomera test range in Australia. The sonic-boom signatures of the NEXST-1 were measured on the ground in order to confirm the possibility of demostrating the low sonic-boom design technology with scaled experimental airplanes for a future low-boom demonstrator program. The measured sonic-boom signatures were compared to the signatures extrapolated from the near-field pressure signatures predicted by CFD and panel method or measured in the supersonic wind tunnel. Low-sonic-boom design technology using gradient-based optimization tool with CFD is developed and applied to a non-axisymmetrical fuselage design concept in order to reduce the drag penalty. JAXA works on a human acceptability study in cooperation with Kawasaki Heavy Industries (KHI) using their sonic-boom simulator. Some low-boom signatures in addition to some typical N-shaped signatures with various peak pressure levels were simulated in the boom box and used for subjective test in order to collect the human acceptability data for future sonic-boom acceptability criteria.
Prediction and measurement of a weak sonic boom from an entry vehicle
Authors: Plotkin Kenneth J. , Franz Russell J. , Haering Edward A.
Published: October 2013

There is a current interest in measuring low-amplitude sonic booms in the atmosphere. This interest is related to verifying the predicted loudness and structure of the shock waves. The reentry of the Stardust comet sample probe on 15 January 2006 provided an opportunity for such a measurement. PCBoom4 was used, together with Stardust’s projected reentry trajectory, to predict the sonic boom footprint. A theory for the sonic boom of a drag-dominated blunt hypersonic vehicle had been developed by Tiegermann [Ph.D. thesis, Cornell University, 1975]. This theory provides an effective F-function based on energy dissipation, using a blast wave analogy and numeric solution. The inputs to that model are the vehicle drag and flight conditions. Tiegermann’s model was implemented in PCBoom4. Drag was obtained by computing deceleration from the expected entry trajectory and multiplying by vehicle weight. A boom with peak overpressure of 0.0524 psf, arriving at 10:00:28.465 UTC, was predicted for a planned measurement site in Ruby Valley, NV, using an atmospheric profile from the upper air reporting station at nearby Elko, NV. The measured sonic boom had a peak overpressure of 0.052 psf and arrived at 10:00:29.719 UTC.
Atmospheric effects on sonic boom loudness
Authors: Pilon Anthony R.
Published: October 2013

The effects of sonic boom propagation through nonstandard atmospheres have been studied. Variations in atmospheric temperature, pressure, humidity, and winds can have significant impact on the structure of the shock waves in the boom signal, as well as the propagation path of the boom. In the study, a hybrid time-frequency domain code was used to calculate finely resolved sonic boom signals for a variety of atmospheric conditions. Idealized near–field signals for low amplitude ‘‘N-wave’’ and ‘‘shaped’’ booms were used to calculate ground level signals. The perceived level metric of Stevens [‘‘Perceived level of noise by Mark VII and decibels (E),’’ J. Acoust. Soc. Am. 51, 575–601 (1972)] was used to quantify the loudness of the calculated booms. Results of the study will be used to determine the impact of atmospheric variations on the acceptability of sonic booms from future supersonic cruise aircraft.
Discrete-time modeling of atmospheric turbulence with application to sonic booms
Authors: Salamone Joe
Published: October 2013

A method is presented that computes a discrete-time model of the atmospheric turbulence effects on sonic booms. First, signal processing techniques are applied to sonic booms to extract the shock profiles from N waves measured on the ground. Next, clean shock profiles are estimated from nonlinear acoustics theory using the measured sonic boom ground data as a reference. A discrete-time model is computed using a Wiener filtering scheme with the ‘‘clean’’ shock profile as the input to the scheme and the measured shock data as the output. The resulting system of equations required to compute a model is ill conditioned. Tikhonov regularization is implemented with the regularization parameter chosen based on inspection of the eigenvalue spectrum of the autocorrelation matrix. Multiple models are obtained for ‘‘low’’ to ‘‘high’’ amounts of turbulence from ground measurements recorded under various atmospheric conditions. Predicted N waves and shaped sonic booms are digitally filtered by the turbulence models. The loudness levels of the sonic booms before and after application of the turbulence models are evaluated.
Supersonic aircraft: Shake, rattle and role
Authors: Liu Sandy
Published: October 2013

There has been a renewed interest worldwide to focus on identifying technological advances that could satisfy the production of a new commercial supersonic aircraft. Although advances have been realized since the Concorde was developed, there is widespread agreement that many challenges remain. At a lesser risk, a supersonic business jet (SBJ) is seen as a technological stepping-stone in the overall tactic of advancing the speed of commercial aircraft. This presentation outlines some of the technological and environmental regulatory challenges facing such an aircraft. This includes a review of the established technical noise working group and activities that address supersonic aircraft environmental matters: sonic boom, aircraft community noise, and aircraft emissions. Federal Aviation Administration (FAA) maintains that a successful supersonic aircraft will depend on its stakeholders’ ability to deal with these key issues. FAA finds it beneficial to work within the international arena for addressing these issues to ensure that all stakeholders’ concerns are considered. Ultimately, successfully addressing concerns regarding sonic boom is a necessary initial condition for regulatory authorities to reconsider existing restrictions on supersonic operations, the key constraint to the business case in the revival to develop a civil supersonic aircraft for the future.
Combined manipulations of the perceived location and spatial extent of the speech-target image predominantly affect speech-on-speech masking
Authors: Huang Ying , Wu Xihong , Huang Qiang , Li Liang
Published: October 2013

Speech maskers contain both informational-masking and energetic-masking components. To fully understand speech masking, it is critical to separate these two types of masking components. This study investigated the effect of the inter-target-source delay (ITSD) on intelligibility of speech when both the speech target and masker were presented by each of the two spatially separated loudspeakers (located at −45 and +45 degrees, respectively). The masker was either two-voice speech (different contents between the two loudspeakers) or steady-state speech-spectrum-noise (uncorrelated between the two loudspeakers). The results show that as the ITSD was decreased from 64 to 0 ms, the target image progressively became funneled into the region around the midline, and the intelligibility of the target was monotonically improved by over 40% when the masker was speech, but by only about 10% when the masker was noise. Under the quiet condition, however, the intelligibility was not affected by the change of ITSD. The results suggest that combined manipulations of perceived location and spatial extent of the speech-target image by changing the ITSD predominantly affect informational masking of speech. [Work supported by China NSF and Canadian IHR.]
Free-field sound localization with nonlinear hearing protection devices
Authors: Lukas Kimberly B. , Ahroon William A.
Published: October 2013

Hearing enhancement and protection devices are being developed for both civilian and military markets that permit the wearer to maintain an awareness of the ambient sound environment and permit face-to-face communications while still protecting the user from high-level impulse noises or blast waves from, for example, handguns, rifles, and shotguns. The impulse noise protection for these devices can range from less than 9 dB peak pressure reduction to reductions of more than 40 dB peak. There has been little research, however, on the ability to use binaural cues to localize sound with such devices. An experiment to evaluate the ability of normal-hearing listeners to localize broadband noise bursts while wearing various nonlinear hearing enhancement and protection systems was conducted in an anechoic environment. Subjects were asked to localize a 60-dB SPL, 200-ms broadband noise burst from a speaker in 1 of 12 different azimuth locations (0 to 330 deg in 30-deg steps) and five different elevations (0, ±15, ±30 deg). The azimuth and elevation errors were measured for each device using circular statistical techniques. Front/back reversals were corrected. The results show a 15- to 20-deg degradation in the wearer’s ability to localize sound when using these hearing protectors.
Selection of attractor sounds for an audio-based navigation system for the visually impaired
Authors: Salisbury Brad S. , Naghshineh Koorosh , Wiener William
Published: October 2013

Research into human hearing has been very laboratory oriented in the sense that the test environments do not replicate most real world situations [J. C. Middlebrooks and D. M. Green, Annu. Rev. Psychol. 42, 135–159 (1991)]. While very useful information is gained from these types of tests, it is difficult to see how real world situations affect sound source localization, recognition, and navigation (walking/way finding) performance. Such information is especially important to people who are visually impaired and dependent on prior knowledge of the environment or audio cues for travel. The research reported here was conducted during the development of an audio-based navigation system. The question that arose was, what constitutes good attractor sounds versus bad sounds? A series of physical tests was developed to identify sounds that performed best from within a group of real-world attractor sounds. Testing was conducted with the aid of participants who were blind or visually impaired. Results of the experiments were consistent with those of Landau et al. [Asst. Technol. 17, 133–143 (2005)].
A study of the equivalent perception between a visual stimulus with a feeling of depth and its associated sound
Authors: Hasegawa Hiroshi , Suzuki Akimasa , Yuyama Ichiro , Ono Hirotaka , Kasuga Masao , Ayama Miyoshi
Published: October 2013

This study investigated the equivalent perception between a visual stimulus and its associated sound. Auditory-visual stimulus presentation experiments were performed using an audio-video clip of a man beating a drum on a road. The visual stimulus, with a perspective view of the road, imparted a depth sensation. Visual stimuli were projected onto a screen of 30.8 (W) (B 16.1 (H) deg. In all, 315 auditory-visual stimuli were produced with combinations of distance between the visual target (the drum) and the observer from (B00 m, the time delay between auditory and visual stimuli from −8F to 8F (1 F=1/30 s), and the sound pressure level of the sound stimulus from (B12 dB. The stimuli were presented to six subjects. In each presentation pattern, the sound pressure level to provide a perceptual strength equivalent to that of the visual target was determined: the equivalent sound pressure level (ESPL). Results show that the ESPL increased as the time delay between the auditory and visual stimuli increased, i.e., the ESPL tended to shift in the direction that the event was closer to the observer. The time delay shifted in the direction that the event was distant from the observer.
Lateralization of amplitude-modulated bone-conducted ultrasounds: Discrimination of interaural time and intensity differences
Authors: Hotehama Takuya , Nakagawa Seiji
Published: October 2013

Ultrasonic vibration generates a sensation of sound via bone conduction; the phenomenon is called bone-conducted ultrasonic (BCU) hearing. Complex sounds also can be perceived by an amplitude-modulated BCU (AM-BCU). In this study, to investigate whether listeners can use an interaural time difference (ITD) in the amplitude envelope and an intensity difference (IID) as cues for lateralization, difference limens for an ITD (ITDL) and an IID (IIDL) for AM-BCU were evaluated. Thirty-kHz sine waves modulated by low-passed noises with cutoff frequencies of 250, 500, 1000, 2000, and 4000 Hz were used as the AM-BCU stimuli. ITDLs and IIDLs for air-conducted (AC) low-passed noises which correspond to modulator of the AM-BCU were also evaluated. Both ITDLs and IIDLs for AM-BCU were observed; AM-BCU was larger in ITDL and smaller in IIDL than AC. The results suggest that it is possible to lateralize AM-BCU using ITD in the envelope and/or IID; however, IID is a more effective cue than ITD.
Modulation masking in monaural and binaural conditions
Authors: Kordus Monika
Published: October 2013

The shape of hypothetical modulation filters was measured in monaural and binaural signal presentation. A sinusoidal 4-kHz carrier was amplitude modulated by low-low-noise (LNN) [A. Kohlrausch et al., Acta Acust. 83, 659–669 (1997)] and a probe tone of a frequency varying from 2 to 256 Hz. Using a three-interval forced-choice (3IFC) procedure the threshold of modulation by the probe tone was determined for the LNN of 16-Hz center frequency and 8-Hz bandwidth, and 64-Hz center frequency and 8-, 16-, or 32-Hz bandwidth. In the monaural condition, signals were presented to the right ear. In the binaural condition, modulation by the LNN was presented to the right ear, and modulation by the probe tone to the left ear. Results showed that masking in the modulation rate domain is characterized by a broad tuning with the highest values of about 17 dB for the monaural condition, and 4 to 9 dB in the binaural condition occurring for probe-tone frequency equal the center frequency of the LNN. The large effect in binaural condition confirms the idea that modulation detection by hypothetical modulation filter bank occurs on a higher level in the auditory system. [Work supported by the Polish Ministry of Education and Science, Grant No. 4T07B03230.]