Temporal offset judgments for concurrent vowels by young, middle-aged, and older adults
Daniel Fogerty, Diane Kewley-Port, and Larry E. Humes
Temporal processing declines with age may reduce the processing of concurrent vowels. For this study, listeners categorized vowel pairs varying in temporal asynchrony as one sound, two overlapping sounds, or two sounds separated by a gap. Two boundaries separating the three response categories, mult ... [J. Acoust. Soc. Am. 131, EL499 (2012)] published Fri May 25, 2012.
Piecewise coherent mode processing of acoustic data recorded on two horizontally separated vertical line arrays
Ilya A. Udovydchenkov, Michael G. Brown, and Timothy F. Duda
Abstract: Motivated by measurements made in the 2004 Long-Range Ocean Acoustic Propagation Experiment (LOAPEX), the problem of mode processing transient acoustic signals collected on two nearby vertical line arrays is considered. The first three moments (centroid, variance, and skewness) of broadban ... [J. Acoust. Soc. Am. 131, EL492 (2012)] published Fri May 25, 2012.
Modified locus equations categorize stop place in a perceptually realistic time frame
Ariane E. Rhone and Allard Jongman
Slope and y-intercepts of locus equations have previously been shown to successfully classify place of articulation for English voiced stop consonants when derived from measurements at vowel onset and vowel midpoint. However, listeners are capable of identifying English voiced stops when less than 3 ... [J. Acoust. Soc. Am. 131, EL487 (2012)] published Fri May 25, 2012.
A novel device allowing for movement and trapping of particles within loop-shaped channels
P. Hahn and J. Dual
Resonant excitation of a fluid cavity inside ultrasonic particle manipulation devices leads to standing waves inside the fluid. Acoustic radiation forces, caused by the nonlinear interaction between the time harmonic pressure field and a particle can be used to manipulate particles towards the nodal ... [AIP Conf. Proc. 1433, 799 (2012)] published Thu May 24, 2012.
Time-averaged acoustic forces acting on a rigid sphere within a wide range of radii in an axisymmetric levitator
Daniele Foresti, Majid Nabavi, and Dimos Poulikakos
Acoustic levitation is a physical phenomenon that arises when the acoustic radiation pressure is strong enough to overcome gravitational force. It is a nonlinear phenomenon which can be predicted only if higher order terms are included in the acoustic field calculation. The study of acoustic levitat ... [AIP Conf. Proc. 1433, 795 (2012)] published Thu May 24, 2012.
Self-organization of granular media in airborne ultrasonic fields
A. I. Bobrovskaya, D. A. Stepanenko, and V. T. Minchenya
The article presents results of experimental and theoretical studies of behaviour of granular media (powder materials) in airborne ultrasonic field created by flexurally-vibrating ring-shaped waveguide with resonant frequency in the range 2040 kHz. Experiments show that action of acoustic radiation ... [AIP Conf. Proc. 1433, 769 (2012)] published Thu May 24, 2012.
Oscillating microbubbles for selective particle sorting in acoustic microfluidic devices
Priscilla Rogers, Lin Xu, and Adrian Neild
In this study, acoustic waves were used to excite a microbubble for selective particle trapping and sorting. Excitation of the bubble at its volume resonance, as necessary to drive strong fluid microstreaming, resulted in the particles being either selectively attracted to the bubble or continuing t ... [AIP Conf. Proc. 1433, 761 (2012)] published Thu May 24, 2012.
Simulation of ultrasonic fields in anisotropic materials using 2D ray tracing method
S. R. Kolkoori, M. -U. Rahaman, P. K. Chinta, R. Boehm, and J. Prager
Ultrasound propagation in inhomogeneous anisotropic materials is difficult to examine because of the directional dependency of elastic properties. Simulation tools play an important role in developing advanced reliable ultrasonic testing techniques for the inspection of anisotropic materials particu ... [AIP Conf. Proc. 1433, 743 (2012)] published Thu May 24, 2012.
Laser ultrasonics system for measurement of speed of sound in gases
J. M. S. Sakamoto, G. M. Pacheco, C. Kitano, and H. A. Machado
In this work we developed a setup to measure the speed of sound in gases using a laser ultrasonics system. The mentioned setup is an all optical system composed by a Q-switched Nd:YAG laser to generate the sound waves, and a fiber optical microphone to detect them. The Nd:YAG provided a laser pulse ... [AIP Conf. Proc. 1433, 737 (2012)] published Thu May 24, 2012.
Development of tough anti cavitation hydrophone by deposition of hydrothermally synthesized lead zirconate titanate poly-crystalline film on reverse surface of titanium front layer
Shinichi Takeuchi, Mutsuo Ishikawa, Norimichi Kawashima, Takeyoshi Uchida, Masahiro Yoshioka et al.
It is difficult to measure the high intensity ultrasound field with generation of acoustic cavitaion, since the electrode of hydrophone will be damaged by erosion and acoustic cavitation. Therefore, we developed the original miniature hydrophone by using hydrothermally synthesized lead zirconate tit ... [AIP Conf. Proc. 1433, 663 (2012)] published Thu May 24, 2012.
Experimental research of high frequency standing wave thermoacoustic refrigerator driven by loudspeaker
Zhang Chunping, Liu Wei, Yang Zhichun, Li Zhengyu, Zhang Xiaoqing et al.
A small size standing wave thermoacoustic refrigerator driven by a high frequency loudspeaker has been experimentally studied. Instead of water cooling, the cold heat exchanger of the refrigerator was cooled by air through fins on it. By working at 600-700 Hz and adjusting the position of the thermo ... [AIP Conf. Proc. 1433, 639 (2012)] published Thu May 24, 2012.
Finite element simulation of single ultrasonic transducer with segmented electrodes to adjust the directional characteristic
Carsten Unverzagt and Bernd Henning
For many applications like level measurement and industry robotics it is of advantage if the directional characteristic of an ultrasonic transducer is changeable or adaptable for the improvement of spatial resolution. Often this goal is reached with the use of ultrasonic transducer arrays, which ele ... [AIP Conf. Proc. 1433, 635 (2012)] published Thu May 24, 2012.
One factor of resonant wavelength shift from onewavelength to two-wavelength resonance in loop-tube-type thermoacoustic cooling system
Shin-ichi Sakamoto, Kenji Shibata, Yuji Kitadani, Yoshitaka Inui, and Yoshiaki Watanabe
Results of this study show that the resonant wavelength of the sound generated in a loop-tube-type thermoacoustic cooling system shifts from one-wavelength to two-wavelength resonance during system operation. The effect of the viscous boundary layer upon the resonant wavelength shift is discussed. T ... [AIP Conf. Proc. 1433, 628 (2012)] published Thu May 24, 2012.
Carbon nanomaterials as broadband airborne ultrasound transducer
M. Daschewski, A. Harrer, J. Prager, M. Kreutzbruck, M. Guderian et al.
A method has been developed for the generation of airborne ultrasound using the thermoacoustic principle applied to carbon materials at the micro- and nanoscale. Such materials are shown to be capable to emitting the ultrasound. We tested the acoustic performance of electrospun polyacrylonitrile-der ... [AIP Conf. Proc. 1433, 624 (2012)] published Thu May 24, 2012.
Study of an open-air traveling-wave thermoacoustic generator
Xiujuan Xie, Jihao Wu, Gang Gao, and Qing Li
Based on linear thermoacoustic theory, an open-air traveling-wave thermoacoustic generator with 1 bar air has been designed and built up. The dimensions of regenerator and resonator influence on the resonant frequency, driver ratio, acoustic power and temperature difference are simulated and optimiz ... [AIP Conf. Proc. 1433, 620 (2012)] published Thu May 24, 2012.
Fundamental study for a working mechanism of Phase Adjuster set on thermoacoustic cooling system
Kazuki Sahashi, Shin-ichi Sakamoto, and Yoshiaki Watanabe
Thermoacoustic cooling systems are drawing attention as next-generation eco-systems that can reuse and transform unused energy such as exhaust energy and solar energy. For the practical use of such systems, improvement of heat-sound energy conversion efficiency remains as an important challenge. We ... [AIP Conf. Proc. 1433, 613 (2012)] published Thu May 24, 2012.
Analysis of entropy generation rate inside the stack of standing-wave thermoacoustic refrigerator
Xiujuan Xie, Gang Gao, and Qing Li
Considering from the second law of thermodynamics, the equation for entropy generation rate near a single-plate, representative of the stack inside thermoacoustic refrigerators was derived in this paper. It indicates that entropy generation is produced due to heat transfer in the x-y direction of fi ... [AIP Conf. Proc. 1433, 609 (2012)] published Thu May 24, 2012.
Influence of different boundary conditions on modulating inlet pressure and velocity of regenerator
Lihua Zhou, Xiujuan Xie, and Qing Li
In present paper, a model driven by double loudspeakers is proposed, which can widely modulate acoustic pressure and oscillating velocity at the inlet boundary of regenerator. For the sake of contrastive analysis, other two models driven by single loudspeaker are built up. Based on linear thermoacou ... [AIP Conf. Proc. 1433, 605 (2012)] published Thu May 24, 2012.
Examining the extraction of artemisinin from artemisia annua using ultrasound
Rhianna Briars and Larysa Paniwnyk
Artemisinin suppresses the life-cycle of the plasmodium parasite which causes malaria. It is found naturally occurring within the trichome glands of the Artemisia annua plant. Traditional methods for extracting artemisinin are time-consuming and have high environmental impact due to the temperatures ... [AIP Conf. Proc. 1433, 581 (2012)] published Thu May 24, 2012.
Applications of the Jones and 4 x 4 matrix formalisms in the theory of optical detection of picosecond acoustic pulses
Mansour Kouyate, Denis Mounier, Thomas Pezeril, and Vitalyi Gusev
The Jones and 4 x 4 matrix formalisms are applied to the analysis of the sensitivity of optical detection of shear acoustic pulse propagating in a layered structure. The polarimetry measurements give directly access to the detection of a shear pulse propagating in an isotropic layer. Simulations sho ... [AIP Conf. Proc. 1433, 557 (2012)] published Thu May 24, 2012.
Numerical simulation of length-limited parametric sound beam
Hideyuki Nomura, Claes M. Hedberg, and Tomoo Kamakura
This study proposes a numerical simulation method that predicts nonlinear propagation of ultrasound beams in order to estimate the sound field of parametric array in the time domain. Basically, the method resorts to solving numerically and compactly the governing equations in a compressible viscous ... [AIP Conf. Proc. 1433, 547 (2012)] published Thu May 24, 2012.
Subharmonics, chaos and beyond
Laszlo Adler, William T. Yost, and John H. Cantrell
While studying finite amplitude ultrasonic wave resonance in a one dimensional liquid-filled cavity formed by a narrow band transducer and a plane reflector, subharmonics of the driver's frequency were observed (1,2) in addition to the expected harmonic structure. Subsequently, it was realized that ... [AIP Conf. Proc. 1433, 527 (2012)] published Thu May 24, 2012.
Time-domain description of point-source acoustic wavefields as a useful approach in ultrasonic techniques
Henryk Lasota
In traditional acoustics, field problems are usually treated in the frequency domain, broadband fields being reduced to superposition of harmonic spectrum components. However, this approach is inherently acausal and it is known that in case of arbitrary signals, the distribution-based, time-domain d ... [AIP Conf. Proc. 1433, 523 (2012)] published Thu May 24, 2012.
Direct calculation of acoustic streaming including the boundary layer phenomena in an ultrasonic air pump
Yuji Wada, Daisuke Koyama, and Kentaro Nakamura
Direct finite difference fluid simulation of acoustic streaming on the fine-meshed three-dimensiona model by graphics processing unit (GPU)-oriented calculation array is discussed. Airflows due to the acoustic traveling wave are induced when an intense sound field is generated in a gap between a ben ... [AIP Conf. Proc. 1433, 507 (2012)] published Thu May 24, 2012.
Experimental study on the determination of the shear-wave reflection coefficient at the solid-liquid interface
Ediguer E. Franco, Julio C. Adamowski, and Flavio Buiochi
This work implements the ultrasonic shear-wave reflectance method for viscosity measurements. A modeconversion device was used for the dynamic viscosity measurement of mineral oil, SAE 40 automotive oil and glycerin samples at room temperature and 1 MHz. A novel signals processing technique that cal ... [AIP Conf. Proc. 1433, 503 (2012)] published Thu May 24, 2012.
Evaluation of nonlinear low-frequency components generated by amplitude-modulated waves in a carbon/carbon composite
Shiro Biwa, Kazuyoshi Nagae, Claude Inserra, and Eiji Matsumoto
In highly inhomogeneous materials such as damaged solids or composites, nonlinearly generated lowfrequency components due to amplitude-modulated waves can be a measure to characterize the materials by nonlinear ultrasonic methods even when higher harmonics are difficult to quantify due to their seve ... [AIP Conf. Proc. 1433, 497 (2012)] published Thu May 24, 2012.
The influence of digital domain on time of flight estimation performance
L. Svilainis, V. Dumbrava, S. Kitov, and A. Chaziachmetovas
Analysis of the time of flight estimation performance when signal digitization is used is presented. The crosscorrelation function peak position was used as time-of-flight estimator. In order to cope with the discrete nature of the cross-correlation the time of flight subsample estimates used interp ... [AIP Conf. Proc. 1433, 479 (2012)] published Thu May 24, 2012.
Modeling and simulation of ultrasonic testing on miniature wheelset
Kazunari Makino, Shiro Biwa, and Hiroshi Sakamoto
An ultrasonic testing was carried out for a fatigue crack with the depth of 3.5 mm which was developed on the surface of the wheel seat of a miniature wheelset test piece by the rotating bending fatigue test. The decrease of the flawecho height in case with the wheel to that without the wheel was 13 ... [AIP Conf. Proc. 1433, 475 (2012)] published Thu May 24, 2012.
Acousto-optic method used to control water pollution by miscible liquids
Kouider Ferria, Lazhar Griani, and Naamane Laouar
An acousto-optic (A.O.) method has been developed for controlling the quality of water mixed by miscible liquids like acetone or ethanol… The liquid mixture is filled in a rectangular glass cell, which is placed orthogonally to the incident collimated beam of light. This cell consists of a pi ... [AIP Conf. Proc. 1433, 76 (2012)] published Thu May 24, 2012.
Acousto-optic interaction of leaky surface acoustic waves in Y-cut LiTaO crystals
J. Belovickis, R. Rimeika, and D. Ciplys
The acousto-optic interaction using radiation of a leaky surface acoustic wave into the bulk of YX-cut LiTaO crystals has been investigated. Optical incidence and diffraction angles corresponding to the strongest acousto-optic interaction were calculated and measured as functions of the acoustic wav ... [AIP Conf. Proc. 1433, 68 (2012)] published Thu May 24, 2012.
AOTF-based 3D spectral imaging system
Vitold Pozhar and Alexander Machihin
The problem of 3D spectral imaging with random spectral access is discussed. Proposed solution is based on dual-channel double acousto-optical (AO) monochromator. Each of two AO cells in it has two spatially separated entrance pupils for transmission of stereoscopic images. In such a scheme spectral ... [AIP Conf. Proc. 1433, 65 (2012)] published Thu May 24, 2012.
Stress dependent dispersion relations of acoustic waves travelling on a chain of point masses connected by anharmonic linear and torsional springs
Mieczyslaw Pluta, Umar Amjad, Hermann Klinghammer, Diwaker Jha, Khurram Tarar et al.
The propagation of a deformation along a flexural beam or plate depends on material properties, geometrical conditions like the beam cross-section, effects of stiffening or softening due to external stress, and last but not least the mode of the wave including its polarization. The time-of-flight (T ... [AIP Conf. Proc. 1433, 471 (2012)] published Thu May 24, 2012.
Characteristics of stereo reproduction with parametric loudspeakers
Shigeaki Aoki, Masayoshi Toba, and Norihisa Tsujita
A parametric loudspeaker utilizes nonlinearity of a medium and is known as a super-directivity loudspeaker. The parametric loudspeaker is one of the prominent applications of nonlinear ultrasonics. So far, the applications have been limited monaural reproduction sound system for public address in mu ... [AIP Conf. Proc. 1433, 47 (2012)] published Thu May 24, 2012.
Dual wavelet energy approach-regression analysis for exploring steel micro structural behavior
Fairouz Bettayeb
Ultrasonic Ndt data are time series data decomposed in signal plus noise obtained from traveling ultrasonic waves inside a material and captured by piezoelectric sensors. The natural inhomogeneous and anisotropy character of steel made material causes high acoustic attenuation and scattering effect. ... [AIP Conf. Proc. 1433, 465 (2012)] published Thu May 24, 2012.
A case study of application of guided waves for detecting corrosion in pipelines
Javad Rostami and Mir Saeed Safizadeh
Every year noticeable amount of money is spent on fixing and replacing the damaged pipes which carry gas and fuel. Since there is a possibility for a catastrophic failure, knowing the proper time of this repair is of great importance. Because significant proportion of failures is due to wall thinnin ... [AIP Conf. Proc. 1433, 439 (2012)] published Thu May 24, 2012.
Ultrasonic nondestructive testing of composite materials using disturbed coincidence conditions
F. Bause, S. Olfert, A. Schroder, J. Rautenberg, B. Henning et al.
In this contribution we present a new method detecting changes in the composite material's acoustic behavior by analyzing disturbed coincidence conditions on plate-like test samples. The coincidence condition for an undamaged GFRP test sample has been experimentally identified using Schlieren measur ... [AIP Conf. Proc. 1433, 427 (2012)] published Thu May 24, 2012.
Obtaining anisotropic velocity data for proper depth seismic imaging
Sergey Egerev, Victor Yushin, Oleg Ovchinnikov, Vladimir Dubinsky, and Doug Patterson
The paper deals with the problem of obtaining anisotropic velocity data due to continuous acoustic impedance-based measurements while scanning in the axial direction along the walls of the borehole. Diagrams of full conductivity of the piezoceramic transducer were used to derive anisotropy parameter ... [AIP Conf. Proc. 1433, 387 (2012)] published Thu May 24, 2012.
Impact-absorbing characteristics by applying ultrasonic vibration
Atsuyuki Suzuki, Eiichiro Ueki, and Jiromaru Tsujino
An impact-absorbing device that facilitates the application of ultrasonic vibrations was devised. Vibration distributions, springback characteristics, and impact-absorption characteristics were measured. We confirm that the springback amount decreases and the impact is absorbed upon the application ... [AIP Conf. Proc. 1433, 369 (2012)] published Thu May 24, 2012.
Welding characteristics of same and different metal specimens using ultrasonic complex vibration welding equipments
Jiromaru Tsujino and Eiichi Sugimoto
Welding characteristics of ultrasonic complex vibration of same and different metal specimens are studied using newly designed ultrasonic complex vibration welding systems. Using complex vibration which induces two-dimensional vibration stress to the welding area, the required vibration velocity and ... [AIP Conf. Proc. 1433, 363 (2012)] published Thu May 24, 2012.
A pilot scale ultrasonic system to enhance extraction processes with dense gases
E. Riera, M. Blasco, A. Tornero, E. Casas, C. Rosello et al.
The use of dense gases (supercritical fluids) as extracting agents has been attracting wide interest for years. In particular, supercritical carbon dioxide is considered nowadays as a green and very useful solvent. Nevertheless, the extraction process has a slow dynamics. Power ultrasound represents ... [AIP Conf. Proc. 1433, 358 (2012)] published Thu May 24, 2012.
Approach warning system for snowplow using aerial-high-power ultrasonic wave with radio wave
Aoyagi Manabu, Amagi Yuta, Miura Hiroaki, Ryota Okeya, Tamura Hideki et al.
An approach warning system for a snowplow and guide was developed by using aerial-high-power ultrasonic transducer. To be robust against some serious factors in winter, ultrasonic signal and radio one were combined on the system, and the flat face side of stepped circular vibrating plate was utilize ... [AIP Conf. Proc. 1433, 354 (2012)] published Thu May 24, 2012.
Development of a single-axis ultrasonic levitator and the study of the radial particle oscillations
Sebastian Baer, Marco A. B. Andrade, Cemal Esen, Julio Cezar Adamowski, and Andreas Ostendorf
This work describes the development and analysis of a new single-axis acoustic levitator, which consists of a 38 kHz Langevin-type piezoelectric transducer with a concave radiating surface and a concave reflector. The new levitator design allows to significantly reducing the electric power necessary ... [AIP Conf. Proc. 1433, 35 (2012)] published Thu May 24, 2012.
Nonlinear behaviour of power ultrasonic transducers for food processing
E. Riera, A. Cardoni, V. M. Acosta, and J. A. Gallego-Juarez
Power ultrasonic systems at laboratory and semi-industrial scale are currently investigated to demonstrate the suitability of ultrasonic waves of high-intensity to industrial applications. It has been shown that intense ultrasonic fields trigger a series of mechanisms in the irradiated media that ma ... [AIP Conf. Proc. 1433, 345 (2012)] published Thu May 24, 2012.
Modulational instability of microbubbles surface modes
Serge Dos Santos, Victor Sanchez-Morcillo, Noe Jimenez, Andre-Pierre Abellard, and Ayache Bouakaz
Starting from the continuous Marmottant model[1], for the vibration of the bubble radius R(t), and a discrete nonlinear model of the discretized radius with periodic boundary conditions and nonlinear coupling between surface modes, MI in bubbles is investigated numerically. After a first step of Sym ... [AIP Conf. Proc. 1433, 311 (2012)] published Thu May 24, 2012.
The importance of control over bubble size distribution in pulsed megasonic cleaning
Marc Hauptmann, Herbert Struyf, Paul Mertens, Marc Heyns, Stefan De Gendt et al.
The presence of acoustic cavitation in the cleaning liquid is a crucial precondition for cleaning action. One can achieve enhanced cleaning by periodically switching the ultrasonic agitation on and off rather than sonicating the liquid in a continuous fashion. The physical effects leading to that im ... [AIP Conf. Proc. 1433, 299 (2012)] published Thu May 24, 2012.
Phase calibration of ultrasonic receivers using cavitation
Miklos Gyongy, James R. T. Collin, and Balazs Rozsa
Although there are many techniques for performing phase calibration on ultrasound transducers, most of these suffer from high cost, complexity, or inaccuracy. In the present work, phase calibration on receive was achieved by the generation of inertial cavitation emissions in 3% agar gel using a 1 MH ... [AIP Conf. Proc. 1433, 295 (2012)] published Thu May 24, 2012.
A study on measurement technique for amount of generated acoustic cavitation-investigation of broadband integrated voltage by comparing with sound pressure and sonochemical luminescence-
Takeyoshi Uchida, Shinichi Takeuchi, and Tsuneo Kikuchi
We have been studying a quantitative technique for measuring the amount of generated acoustic cavitation. Cavitation plays a key role in several fields. Therefore, a precise technique for measuring the amount of generated cavitation is required in order to attain a balance between safety and effecti ... [AIP Conf. Proc. 1433, 291 (2012)] published Thu May 24, 2012.
Evaluation of concrete cover by surface wave technique: Identification procedure
Bogdan Piwakowski, Mariusz Kaczmarek, and Pawel Safinowski
Concrete cover degradation is induced by aggressive agents in ambiance, such as moisture, chemicals or temperature variations. Due to degradation usually a thin (a few millimeters thick) surface layer has porosity slightly higher than the deeper sound material. The non destructive evaluation of conc ... [AIP Conf. Proc. 1433, 276 (2012)] published Thu May 24, 2012.
Modification of scalar potential theory for surface acoustic wave devices to take slowness asymmetry into account
Ken-ya Hashimoto, Tatsuya Omori, and Chang-Jun Ahn
This paper discusses modification of the scalar potential (SP) theory for the analysis of surface acoustic wave (SAW) devices to take asymmetry of the SAW slowness curve into account. First, it is shown that the SP theory is equivalent to the two-dimensional wave equation for a shear-vertical bulk w ... [AIP Conf. Proc. 1433, 271 (2012)] published Thu May 24, 2012.
Particle manipulation using acoustic radiation forces in micromachined devices
Jurg Dual, Dirk Moller, Adrian Neild, Stefano Oberti, Thomas Schwarz et al.
Acoustic radiation forces are increasingly used for the handling of micron sized particles suspended in a fluid. The primary radiation forces arise as a nonlinear effect when an acoustic wave interacts with a single particle. In addition, secondary acoustic forces arise when several particles are pr ... [AIP Conf. Proc. 1433, 27 (2012)] published Thu May 24, 2012.
Automated non destructive testing by non-contact surface waves
Bogdan Piwakowski, Mariusz Kaczmarek, and Pawel Safinowski
The paper presents an automated device designed for the non destructive control and characterization of materials using ultrasonic surface waves (SW). The system of transmission and reception of waves is non-contact, i.e. uses air as the coupling medium between transducers and samples. The solution ... [AIP Conf. Proc. 1433, 255 (2012)] published Thu May 24, 2012.
Scattering and attenuation of surface acoustic waves and surface skimming longitudinal polarized bulk waves imaged by Coulomb coupling
A. Habib, A. Shelke, M. Pluta, U. Pietsch, T. Kundu et al.
Coulomb coupling has been applied for vector contrast imaging of surface acoustic waves and surface skimming longitudinal polarized waves travelling on or in a 5 mm thick, Y-Z cut Lithium Niobate single crystal. The excitation and detection of acoustic waves was performed by Coulomb coupling. For ex ... [AIP Conf. Proc. 1433, 247 (2012)] published Thu May 24, 2012.
Sonoporation generator design and performance evaluation
L. Svilainis, A. Chaziachmetovas, R. Jurkonis, and D. Kybartas
We propose to perform the sonoporation by use of direct excitation employing the square wave pulser. Addition of the arbitrary waveform generator and programmable high voltage power supply to the pulser should allow for more economical experiment arrangement. Excitation stage has to be capable of tr ... [AIP Conf. Proc. 1433, 241 (2012)] published Thu May 24, 2012.
Trends in sonochemistry and ultrasonic processing
Timothy J. Mason
It is always a valuable exercise to review the origins and developments of a technology before going on to look at future prospects. Such an exercise allows one to judge both whether that technology has real long term applications or is simply of transient interest on a laboratory scale. In the fiel ... [AIP Conf. Proc. 1433, 21 (2012)] published Thu May 24, 2012.
Improvement of synthetic aperture techniques by means of the coarray analysis
C.J. Martin-Arguedas, O. Martinez-Graullera, D. Romero-Laorden, M. Perez-Lopez, and L. Gomez-Ullate
In the field of ultrasonic imaging, the synthetic aperture techniques are well known due to their ability for obtain images using fewer resources. Initially, these techniques were developed to reduce the cost and complexity of phased array instrumentation. Although these drawbacks have already been ... [AIP Conf. Proc. 1433, 189 (2012)] published Thu May 24, 2012.
A new beamforming process based on the phase dispersion analysis
Oscar Martinez-Graullera, David Romero-Laorden, Carlos J. Martin-Arguedas, Alberto Ibanez, and Luis G. Ullate
To improve the results of the Delay-And-Sum (DAS) beamformer a weighting factor based on a measurement of the phase dispersion of the signals in the image point under consideration has been proposed. With this objective, the spectral analysis of the phase dispersion is used here to obtain a new desc ... [AIP Conf. Proc. 1433, 185 (2012)] published Thu May 24, 2012.
Modular architecture for ultrasound beamforming with FPGAs
J. F. Cruza, J. Camacho, J. Brizuela, J. M. Moreno, and C. Fritsch
Reception beamforming requires a high-resolution time base to keep low delay quantization lobes. Usually signals acquired at the Nyquist sampling rate are up-sampled by a factor of 4 to 16 to achieve the required time-resolution. Although this has been carried out for decades using fractional delay ... [AIP Conf. Proc. 1433, 181 (2012)] published Thu May 24, 2012.
Imaging through a convex interface with unknown position and shape using an ultrasonic linear array
Marcelo Y. Matuda, Flavio Buiochi, and Julio C. Adamowski
This paper presents a technique for improving the internal imaging of a solid object immersed in water using an ultrasonic array. This technique consists in determining the position and shape of a convex object surface using a combination of synthetic transmit aperture (STA) and sign coherence facto ... [AIP Conf. Proc. 1433, 177 (2012)] published Thu May 24, 2012.
A new technique for fast dynamic focusing law computing
C. Fritsch, J. F. Cruza, J. Brizuela, J. Camacho, and J. M. Moreno
Dynamic focusing requires computing the individual delays for every element and every focus in the image. This is an easy and relatively fast task if the inspected medium is homogeneous. Nevertheless, some difficulties arise in presence of interfaces (i.e, wedges, immersion, etc.): refraction effect ... [AIP Conf. Proc. 1433, 165 (2012)] published Thu May 24, 2012.
Air-coupled ultrasonic spectroscopy applied to the study of the properties of paper produced from mineral powder (mineral paper).
D. A. Soto, R. A. Salas, and T. E. Gomez Alvarez-Arenas
A recent technology has been introduced into the paper industry that makes possible to produce paper materials by replacing the cellulose fibres by a mineral powder, achieving a more environmentally friendly product compared with conventional paper. The purpose of this work is to determine the possi ... [AIP Conf. Proc. 1433, 155 (2012)] published Thu May 24, 2012.
Application of nonlinear acoustics for the study of relaxation processes in granular materials
V. Yu. Zaitsev, V. Gusev, and V. Tournat
We report observations of slow relaxation of the weak-contact network in a dry granular packing after gentle taps. Non-conventional nonlinear acoustic technique is used. Its high sensitivity makes it possible to monitor in detail the restoration of the weak-contact network. With a high precision, it ... [AIP Conf. Proc. 1433, 151 (2012)] published Thu May 24, 2012.
Measurement of the emission of Lamb waves by a PVDF membrane hydrophone
Martin Schmitt, Sabrina Tietze, Wei Liang, and Gerhard Lindner
The emission of sound waves resulting from mode conversion of Lamb waves propagating on thin glass plates submerged into water was investigated by a PVDF membrane hydrophone. The antisymmetrical zero order Lamb wave mode was excited by a piezoelectric single phase transducer operated at a frequency ... [AIP Conf. Proc. 1433, 133 (2012)] published Thu May 24, 2012.
Model based separation of transmitted and received signal for single transducer distance measurement applications
A. Schroder and B. Henning
Single transducer distance measurement systems have a blind zone which is increased if the transmitted signals are coded to reduce errors due to crosstalk. A method to reduce this blind zone is a model based separation of the transmitted and received signal. This contribution compares two systems, o ... [AIP Conf. Proc. 1433, 125 (2012)] published Thu May 24, 2012.
Acousto-optic investigation of acoustic waves propagation in anisotropic medium
Nataliya V. Polikarpova, Evgeny A. Djakonov,, and Vitaly B. Voloshinov
The paper presents new results on analysis of propagation and reflection of acoustic waves in the single crystal tellurium dioxide. The investigation was carried out by means of the acousto-optic methods. We observed in a cell with a specially chosen configuration, a simultaneous generation of two e ... [AIP Conf. Proc. 1433, 110 (2012)] published Thu May 24, 2012.
Ultrasonic nondestructive inspection of solid objects
Tadeusz Stepinski
Ultrasonic testing (UT) has been used for nondestructive evaluation (NDE) of materials for more than half a century. A number of NDE techniques have been developed and specific standards have been created for the UT applications in different areas of engineering. UT has two main goals related to ins ... [AIP Conf. Proc. 1433, 11 (2012)] published Thu May 24, 2012.
Acousto-optic interaction in TeO and LiNbO devices with surface generation of bulk acoustic waves
Arseniy S. Trushin, Pavel A. Nikitin, and Anastasia V. Muromets
In this paper, a theoretical and experimental study is presented related to light interaction with bulk acoustic waves generated from a surface of piezoelectric LiNbO and TeO crystals. A paratellurite acousto-optic cell was designed and developed on base of conversion of acoustic modes during a refl ... [AIP Conf. Proc. 1433, 102 (2012)] published Thu May 24, 2012.
A parametric study of error in the parabolic approximation of focused axisymmetric ultrasound beams
Joshua E. Soneson
The parabolic approximation results in a tractible model for studying ultrasound beams, but the limits of validity of the approximation are often presented only qualitatively. In this work the most common model for axisymmetric ultrasound beam propagation, the KuznetsovZabolotskayaKhokhlov equation, ... [J. Acoust. Soc. Am. 131, EL481 (2012)] published Thu May 24, 2012.
Lamb wave near field enhancements for surface breaking defects in plates
A. R. Clough and R. S. Edwards
Near field surface wave ultrasonic enhancements have previously been used to detect surface breaking defects in thick samples using Rayleigh waves. Here, we present analogous surface wave enhancements for Lamb waves propagating in plates. By tracking frequency intensities in selected regions of time ... [J. Appl. Phys. 111, 104906 (2012)] published Wed May 23, 2012.
Broadband aperiodic air coupled ultrasonic lens
John T. Welter, Shamachary Sathish, Josiah M. Dierken, Philip G. Brodrick, Matthew R. Cherry et al.
This paper demonstrates the possibility of subwavelength, defined as less than the incident wavelength, broadband focusing in an aperiodic air coupled ultrasonic lens. A near field probe is used to detect well defined resonances from 75 to 125 kHz. The spatial resolution at each of the resonant freq ... [Appl. Phys. Lett. 100, 214102 (2012)] published Tue May 22, 2012.
Reflection and refraction of sound on smoothed boundaries.
Nick Maltsev
Asymptotic solutions for the system of Euler equations for small motions of compressive fluid are received for two liquid half spaces divided by smoothed transition of sound velocity and density from one half space to another. Vertical Green function is integrated by Fast Field Program for differen ... [POMA 14, 070007 (2012)] published Mon May 21, 2012.
On near-field acoustical inverse measurements of partially coherent sources
Alan T. Wall, Kent L. Gee, Tracianne B. Neilsen, and Michael M. James
The sources of jet noise have been investigated through the use of near-field array measurements. An understanding of spatial coherence properties in the jet near field leads to insight about source composition. A metric called coherence length is a useful tool for summarizing near-field coherence ... [POMA 11, 040007 (2012)] published Mon May 21, 2012.
Noise attenuation by sonic crystal barriers made of microperforated units
Victor M. Garcia-Chocano, Suitberto Cabrera, and Jose Sanchez-Dehesa
This work studies the absorptive properties of periodic arrays of microperforated cylindrical shells. Structures made of cylinders 3 meters height have been constructed and their reflectance and transmittance spectra are measured in open air at normal incidence. A broadband strong attenuation is fou ... [POMA 15, 015001 (2012)] published Fri May 18, 2012.
Internal visualization of finished guitars and their sound
Jesus A. Torres, Gabriel Hernandez, Alejandro Granados, and Abel Garcia
The internal structure of two classical guitars (using a near infrared transmittance technique) and typical sound spectrums from each were compared. Both guitars were crafted by Paracho luthiers: one with carbon fiber reinforcements, and the other one with traditional Torres design. For the experime ... [POMA 11, 035005 (2012)] published Fri May 18, 2012.