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Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on

Issue 4 • Date April 2006

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  • IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control - April 2006

    Publication Year: 2006 , Page(s): 0_1 - 0_2
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  • [Inside front cover]

    Publication Year: 2006 , Page(s): 3
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  • [Back inside cover]

    Publication Year: 2006 , Page(s): 0_4
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  • Table of contents - Vol. 53 No. 4

    Publication Year: 2006 , Page(s): 5 - 6
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  • Information for Contributors with Multimedia Addition

    Publication Year: 2006 , Page(s): 665 - 669
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  • A multimedia example

    Publication Year: 2006 , Page(s): 670
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  • Call for Papers - Special Issue on High Resolution Ultrasonic Imaging in Industrial, Material and Biomaterial Applications 2006

    Publication Year: 2006 , Page(s): 671
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  • 2006 IEEE International Ultrasonics Symposium - First Call for Papers

    Publication Year: 2006 , Page(s): 672
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  • Single crystals and nonlinear process for outstanding vibration-powered electrical generators

    Publication Year: 2006 , Page(s): 673 - 684
    Cited by:  Papers (23)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (561 KB) |  | HTML iconHTML  

    This paper compares the performances of vibration-powered electrical generators using a piezoelectric ceramic and a piezoelectric single crystal associated to several power conditioning circuits. A new approach of the piezoelectric power conversion based on a nonlinear voltage processing is presented, leading to three novel high performance power conditioning interfaces. Theoretical predictions and experimental results show that the nonlinear processing technique may increase the power harvested by a factor of 8 compared to standard techniques. Moreover, it is shown that, for a given energy harvesting technique, generators using single crystals deliver 20 times more power than generators using piezoelectric ceramics. View full abstract»

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  • Modeling of ultrasonic wave propagation in integrated piezoelectric structures under residual stress

    Publication Year: 2006 , Page(s): 685 - 696
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (777 KB) |  | HTML iconHTML  

    The objective of this study is to understand the role of residual stress in piezoelectric layers in order to predict the performance of integrated structures. This is of particular importance in thick or thin film technology. Considering a bulk piezoelectric material, the Christoffel equation for a piezoelectric material is modified to take into account a uniform residual stress on a given cross section. A numerical study of its influence is carried out on the slowness curves and coupling coefficients of a lithium niobate material. In a second part, modified Christoffel tensor is used to calculate the dispersion curves of Lamb waves in a piezoelectric plate. The Lamb modes are found to be sensitive to the residual stress. In particular, it is shown how the behavior of the first Lamb modes is modified with residual stress. In a third part, these results are extended to a piezoelectric film laid down on a substrate in order to model the importance of these phenomena on the behavior of an integrated structure. The numerical study of guided waves in a lithium niobate plate is performed first, then the case of a lithium niobate film laid down on a silicon substrate is considered. View full abstract»

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  • Vibration of micromachined circular piezoelectric diaphragms

    Publication Year: 2006 , Page(s): 697 - 706
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1736 KB) |  | HTML iconHTML  

    The electrically and mechanically excited resonances in micromachined circular piezoelectric diaphragms have been investigated. The diaphragm structures were piezoelectric unimorphs consisting of Pb(Zr/sub 0.52/,Ti/sub 0.48/)O/sub 3/ (PZT) films and thermally grown silicon oxide (SiO/sub 2/) layers. For electrical excitation, ring-shaped interdigitated (IDT) electrodes formed on the top of the PZT layer were used to induce strain in the diaphragms. The diaphragm structures behaved much like circular membranes in which the membrane tension was /spl sim/206 N/m, at the fundamental modes. For higher modes, the resonance frequencies deviated from the theoretical values due to the finite stiffness of the diaphragms. Under mechanical drive, both symmetric and asymmetric modes were excited. However, for electrical excitation, the symmetric modes were dominant due to the symmetry of the driving IDT electrodes. At a pressure of 727 Torr, the quality factor was /spl sim/250, and this rose to 2000 at pressures below 1 Torr. When a forward bias was applied to the diaphragm, the membrane tension decreased, but under reverse biases the tension increased. However, because of repoling under reverse biases greater than the coercive field of the PZT film, the achievable increase in the membrane tension was limited. In the diaphragm structure, the nonlinear vibration was governed by geometric nonlinearity rather than material nonlinearity. In addition, evidence of non-180/spl deg/ domain wall motion of the PZT layer in released diaphragms was observed. View full abstract»

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  • Phase-noise reduction in surface wave oscillators by using nonlinear sustaining amplifiers

    Publication Year: 2006 , Page(s): 707 - 715
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (844 KB) |  | HTML iconHTML  

    Nonlinear sustaining amplifier operation has been investigated and applied to high-power negative resistance oscillators (NRO), using single-port surface transverse wave (STW) resonators, and single-transistor sustaining amplifiers for feedback-loop STW oscillators (FLSO) stabilized with two-port STW devices. In all cases, self-limiting, silicon (Si)-bipolar sustaining amplifiers that operate in the highly nonlinear AB-, B-, or C-class modes are implemented. Phase-noise reduction is based on the assumption that a sustaining amplifier, operating in one of these modes, uses current limiting and remains cut off over a significant portion of the wave period. Therefore, it does not generate 1/f noise over the cut-off portion of the radio frequency (R-F) cycle, and this reduces the close-in oscillator phase noise significantly. The proposed method has been found to provide phase-noise levels in the -111 to -119 dBc/Hz range at 1 KHz carrier offset in 915 MHz C-class power NRO and FLSO generating up to 23 dBm of RF-power at RF versus dc (RF/dc) efficiencies exceeding 40%. C-class amplifier design techniques are used for adequate matching and high RF/dc efficiency. View full abstract»

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  • Sol-gel transition in agar-gelatin mixtures studied with transient elastography

    Publication Year: 2006 , Page(s): 716 - 723
    Cited by:  Papers (3)
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    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (973 KB) |  | HTML iconHTML  

    Using the shear wave propagation in solids, the transient elastography technique has been developed to assess the elastic properties of soft tissues. Here, a new approach of transient elastography allows assessing the viscoelastic properties of soft tissues. In this paper, the method is used to follow-up the sol-gel transition of an agar-gelatin mixture noninvasively. The shear wave velocity and shear wave attenuation through the mixture were continuously monitored in the audible range of frequencies (from 50 Hz to 200 Hz). The observed changes in velocities and attenuations as a function of frequency confirmed the validity of the Voigt's model to describe the gel at its stable mechanical state. By a simple inverse problem approach, based on the one-dimensional (1-D) Helmholtz equation, the elasticity and the viscosity of such a mixture were recovered as a function of time. The results obtained are in good agreement with the literature and theoretical predictions. Overall, they demonstrate the high sensitivity of the transient elastography measurements to the rheological parameter changes in agar-gelatin mixtures during gelation. View full abstract»

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  • Modeling and phantom studies of ultrasonic wall shear rate measurements using coded pulse excitation

    Publication Year: 2006 , Page(s): 724 - 734
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (839 KB) |  | HTML iconHTML  

    Wall shear rate (WSR) is the derivative of blood velocity with respect to vessel radius at the endothelial cell (EC) surface. The product of WSR and blood viscosity is the wall shear stress (WSS) that has been identified as an important factor for atherosclerosis development. High echo signal-to-noise ratio (eSNR) and high spatial resolution are crucial for minimizing the errors in WSR estimates. By transmitting coded pulses with time-bandwidth product greater than one, high eSNR from weak blood scatter can be achieved without increasing instantaneous power or sacrificing spatial resolution. This paper summarizes a series of measurements in a straight tube (5-mm diameter), constant velocity flow phantom using a 10 MHz transducer (60% bandwidth, f/1.5) imaged with a 72° Doppler angle, 125 MHz sampling frequency and 1 kHz pulse repetition frequency. Measurements were made using a frequency-modulated (FM) code, phase-modulated (PM) codes, and uncoded broadband and narrow band pulse transmissions. Both simulation and experimental results show that coded-pulse excitation increases accuracy and precision in WSR estimation for laminar flow over a broad range of peak velocity values when compared to standard pulsing techniques in noise-limited conditions (eSNR < 30 dB). The code sequence arid its length are selected to balance range lobe suppression with eSNR and echo coherence enhancements to minimize WSR errors. In our study, the combination of an eight bit Optimal coded pulse with a Wiener compression filter yielded the highest WSR estimation performance. View full abstract»

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  • Noise reduction for Doppler ultrasound signal based on the adapted local cosine transform and the garrote thresholding method

    Publication Year: 2006 , Page(s): 735 - 745
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2101 KB) |  | HTML iconHTML  

    In this paper, a novel approach, using the adapted local cosine transform combined with the non-negative garrote thresholding, is proposed to remove noise from the Doppler ultrasound signal. In the proposed approach, the local cosine transform is first performed on the signal of interest followed by a search algorithm to select the best basis. Then the coefficients of the obtained best basis are thresholded based on the non-negative garrote thresholding method. By means of the thresholded coefficients of the best basis, the signal is reconstructed. In the simulation study, the estimation precisions of the mean frequency waveform and the spectral width waveform are studied for the signal after denoising. The simulation and clinical results have shown that the proposed approach is superior to ones based on the wavelet transform, especially under low signal-to-noise ratio (SNH) circumstances. View full abstract»

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  • Evaluation of the effect of preload force on resonance frequencies for a traveling wave ultrasonic motor

    Publication Year: 2006 , Page(s): 746 - 753
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (586 KB) |  | HTML iconHTML  

    In this paper, a novel method of numerical computation of the natural frequencies, depending on the most important running parameters for an ultrasonic motor, is described. The analyzed configuration by the Space Division of Alenia Spazio, Rome, within an Italian Space Agency (ASI) development program, is the flexural traveling wave one. The dynamic equations for the stator and the rotors of the ultrasonic motor are assumed into a differential system, whose equations are coupled by terms that represent interface generalized forces. In order to calculate natural frequencies of the motor-coupled terms of the equations are worked out with respect to the variables of the degrees of freedom. Hence, the mass, damping, and stiffness matrix for the whole system are obtained, then resonance frequencies, depending on the most important running parameters such as axial preload of the motor, are calculated. The results are compared with numerical ones, obtained by a finite element modeling (FEM) model, showing a good agreement. View full abstract»

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  • Laser ultrasound measurement and finite-element simulation on the dispersion behaviors of acoustic waves propagating along wedges with bilinear cross sections

    Publication Year: 2006 , Page(s): 754 - 760
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (933 KB) |  | HTML iconHTML  

    In this research, dispersion behaviors of anti-symmetric flexural (ASF) modes propagating along the tip of a bilinear wedge (BW) are investigated. A BW has a cross section with two apex angles, as opposed to a linear wedge (LW) whose cross section has a single apex angle. In the literature, many studies regarding the dispersion behaviors of ASF modes have been reported for LWs, but not for BWs. In this study, laser ultrasonic measurements and finite-element numerical simulations are used to investigate the dispersion behavior of BW-ASF modes. It was found that a BW-ASF mode arises as a result of mode coupling between two LW-ASF modes of the same order corresponding to the two apex angles of the BW. View full abstract»

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  • Measurement of low-frequency ultrasonic wave in water using an acoustic fiber

    Publication Year: 2006 , Page(s): 761 - 767
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (346 KB) |  | HTML iconHTML  

    An acoustic fiber sensor for measurement of ultrasonic waves, which used the approximate Raman-Nath diffraction effect where light diffraction waves were generated in an optical fiber by strain due to the ultrasonic waves, was proposed and examined. In order to characterize the acoustic fiber sensor as a basic study, measurements of low-frequency ultrasonic waves in water were examined using a step index fiber operating as a detection sensor. The results showed that characteristics of detected signals agreed with the theoretical prediction based on Fraunhofer diffraction. This indicates that our proposed fiber sensor can be used for the detection of low-frequency ultrasonic waves as well as the transmission of light diffraction signals. View full abstract»

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  • The application of time-frequency analysis to the air-coupled ultrasonic testing of concrete

    Publication Year: 2006 , Page(s): 768 - 776
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1242 KB) |  | HTML iconHTML  

    Air-coupled ultrasound has been used for the nondestructive evaluation of concrete, using broad bandwidth electrostatic transducers and chirp excitation. This paper investigates the benefits of using time-frequency analysis in such situations, for both waveform retrieval and imaging in the presence of low signal levels. The use of the short-term Fourier transform, the wavelet transform, and the Wigner-Ville distribution all are considered, in which accurate tracking of the ultrasonic chirp signals is demonstrated. The Hough transform then is applied as a filter. An image of a steel reinforcement bar in concrete has been produced to illustrate this approach. View full abstract»

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  • On the development and testing of a guided ultrasonic wave array for structural integrity monitoring

    Publication Year: 2006 , Page(s): 777 - 785
    Cited by:  Papers (4)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (858 KB) |  | HTML iconHTML  

    The prototype of a guided ultrasonic wave array for the structural integrity monitoring of large, plate-like structures has been designed, built, and tested. The development of suitably small transducers for the excitation and measurement of the first antisymmetric Lamb wave mode A/sub 0/ is described. The array design consists of a ring of 32 transducers, permanently bonded to the structure with a protective membrane, in a compact housing with the necessary multiplexing electronics. Using a phased addition algorithm with dispersion compensation and deconvolution in the wavenumber domain, a good dynamic range can be achieved with a limited number of transducers. Limitations in the transducer design and manufacture restricted the overall dynamic range achieved to 27 dB. Laboratory measurements for a steel plate containing various defects have been performed. The results for standard defects are compared to theoretical predictions and the sensitivity of the array device for defect detection has been established. Simulated corrosion pitting and a defect cut with an angle grinder simulating general corrosion were detected. View full abstract»

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  • DNA immobilization and SAW response in ZnO nanotips grown on LiNbO3 substrates

    Publication Year: 2006 , Page(s): 786 - 792
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (468 KB) |  | HTML iconHTML  

    DNA immobilization enhancement is demonstrated in a structure consisting of ZnO nanotips on 128° Y-cut LiNbO3.The ZnO nanotips are grown by metal-organic chemical vapor deposition (MOCVD) on the top of a SiO2 layer that is deposited and patterned on the LiNbO3 SAW delay path. The effects of ZnO nanotips on the SAW response are investigated. X-ray diffraction and scanning electron microscopy are used to analyze the ZnO nanotips, which are of single crystalline quality, and they are uniformly aligned with their c-axis perpendicular to the substrate surface. The photoluminescence (PL) spectrum of the ZnO nanotips shows strong near bandedge transition with insignificant deep level emission, confirming their good optical property. DNA immobilization enhancement is experimentally validated by radioactive labeling tests and SAW response changes. The ZnO nanotips enhance the DNA immobilization by a factor of 200 compared to ZnO film with flat surface. DNA hybridization with complementary and noncomplementary second strand DNA oligonucleotides is used to study the selective binding of the structure. This device structure possesses the advantages of both traditional SAW sensors and ZnO nanostructures. View full abstract»

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  • Ultramultiple roundtrips of surface acoustic wave on sphere realizing innovation of gas sensors

    Publication Year: 2006 , Page(s): 793 - 801
    Cited by:  Papers (1)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2151 KB) |  | HTML iconHTML  

    A thin beam of wave usually diverges due to diffraction, which is a limitation of any device using such waves. However, a surface acoustic wave (SAW) on a sphere with an appropriate aperture does not diverge but is naturally collimated, realizing ultramultiple roundtrips along an equator of the sphere. This effect is caused by the balance between diffraction and focusing on a spherical surface, and it enables realization of high-performance ball SAW sensors. The advantage of ball SAW is most fully appreciated when applied to a very thin sensitive film for which the multiple-roundtrip enhances the sensitivity, but the attenuation loss is not very large. It is exemplified in a hydrogen gas sensor that realizes a wide sensing range of 10 ppm to 100% for the first time, and realizes relatively fast response time of 20 s without heating the sensitive film. View full abstract»

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  • New equivalent lumped electrical circuit for piezoelectric transformers

    Publication Year: 2006 , Page(s): 802 - 809
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (690 KB) |  | HTML iconHTML  

    A new equivalent circuit is proposed for a contour-vibration-mode piezoelectric transformer (PT). It is shown that the usual lumped equivalent circuit derived from the conventional Mason approach is not accurate. The proposed circuit, built on experimental measurements, makes an explicit difference between the elastic energies stored respectively on the primary and secondary parts. The experimental and theoretical resonance frequencies with the secondary in open or short circuit are in good agreement as well as the output "voltage-current" characteristic and the optimum efficiency working point. This circuit can be extended to various PT configurations and appears to be a useful tool for modeling electronic devices that integrate piezoelectric transformers. View full abstract»

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  • Errata - High power universal piezoelectric transformer

    Publication Year: 2006 , Page(s): 810 - 816
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (540 KB) |  | HTML iconHTML  

    First Page of the Article
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Aims & Scope

IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control focuses on the theory, design, and application on generation, transmission, and detection of bulk and surface mechanical waves.

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Editor-in-Chief
Steven Freear
s.freear@leeds.ac.uk