Showing papers in "Ultrasonics in 2009"

TL;DR: The paper demonstrates that artificial neural networks can be successfully used in modelling the velocity-strength relationship and enables us to easily and reliably estimate the compressive strength of concrete by using only the ultrasonic pulse velocity value and some mix parameters of concrete.

TL;DR: The results from acoustoelastic measurements on the seven-wire steel strands show the potential and the suitability of the proposed guided wave method for evaluating the stress levels in the tested seven- wire steel strands.

TL;DR: An improved automatic TOF picker based on the Akaike information criterion (AIC) has been developed and successfully adopted into CURE, and allows it to generate reliable quantitative values reliably.

TL;DR: A general theoretical approach to the development of zero-thickness encapsulation models for contrast microbubbles is proposed, and it is shown that the use of the nonlinear theory for shell viscosity allows one to model the "compression-only" behavior.

TL;DR: It was found that the stiffness matrix required to describe the effect of axial load is proportional to the mass matrix, which makes the extension to existing software trivial.

TL;DR: It has been shown that time reversal can be used to achieve temporal recompression of Lamb waves under broadband signal excitation and the broad band excitation can also improve the resolution of the technique in detecting closely located defects.

TL;DR: A new automatic determination technique of the first arrival times of AE signals is presented for thin metal plates based on Akaike's information criterion and uses a specific characteristic function, which is sensitive to change of frequency in contrast to others such as envelope of the signal.

TL;DR: Developing acoustically active nanoemulsions for camptothecin encapsulation to circumvent delivery problems and illustrate a drug-targeting effect is illustrated.

TL;DR: It is shown that, as the acoustic pressure amplitude is increased, the resonance frequency of a lipid-shelled microbubble tends to decrease in comparison with its linear resonance frequency, and the conclusion is drawn that the further development of shell models could be improved by the consideration of nonlinear rheological laws.

TL;DR: The goal is to define design strategies for implementing several spatially separated ultrasonic manipulation functions in series for use in advanced particle or cell handling and processing applications.

TL;DR: An equation of radial oscillation for an encapsulated bubble near a plane rigid wall is derived and the equation is then used to simulate the echo from a layer of contrast agents localized on a wall, showing that the fundamental spectral component of adherent bubbles is perceptibly stronger than that of free bubbles.

TL;DR: Adapted signal processing technique are presented to evaluate the coherent phase and group velocities and also the coherent attenuation parameter, and the sensitivity of these three parameters with the properties of concrete is discussed, as well as the necessity to use coherent waves to obtain accurate results.

TL;DR: The results suggest that the free radicals, produced by water sonolysis, have an important role in the changes of structural order.

TL;DR: A comparative study of methods based on the wavelet transform for improving the signal-to-noise ratio in ultrasonic non-destructive testing of materials with a coarse-grained structure.

TL;DR: The outcome of this research indicates that once fully developed and calibrated, the combined acousto-optic system will constitute a universal reference tool in the wide, 100 MHz bandwidth.

TL;DR: The present work extends the analysis of the radiation force to the case of a high-order Bessel beam (HOBB) of positive order m having an angular dependence on the phase phi and derives the general expression for the Radiation force function YJm,st(ka,beta,m)<0), which is the radiationforce per unit characteristic energy density and unit cross-sectional surface.

TL;DR: Three angle independent vector velocity methods for blood velocity estimation can yield quantitative insight into flow dynamics and visualize complex flow patterns, which potentially can give the clinician a novel tool for cardiovascular disease assessment.

TL;DR: The findings of this study indicate that ultrasound treatment induced the activation of nuclear factor-kappaB as an early stress response in Sarcoma 180 cells and can provide a basis for explaining the synergistic effect of ultrasound and hematoporphyrin.

TL;DR: The results show that for x-y mode waves, the stop bands are easily formed in the materials with triangular pores, but hard for square ones, while a critical porosity exists for the formation of the absolute band gaps.

TL;DR: The study confirmed BUSS's capability to discriminate between stages of bone atrophy and in particular to distinguish early changes induced by osteoporosis.

TL;DR: A critical analysis of potential performance of previous ultrasonic research trends for temperature estimation inside materials, using different processing techniques proposed in frequency, time and phase domains and a very small quadratic tendency appeared in the results obtained from experimental echo registers.

TL;DR: The attenuation model implemented in this code to give an account of wave scattering phenomenon through polycrystalline materials is described to provide a quantitative proof that taking into account the attenuation in the ATHENA code dramatically improves the results in terms of the amplitude of the echoes.

TL;DR: The results presented in this research show that VA allows seed detection within a human prostate regardless of their orientation, as well as imaging intra-prostatic calcifications.

TL;DR: A theoretical analysis of thickness vibrations in piezoelectric plates of crystals with 6mm symmetry is performed and thickness vibrations frequencies and modes as well as impedance are calculated and examined.

TL;DR: It is shown that it is possible to restore in vivo ultrasound images using an assumed point-spread function and hence it is concluded that an exact point- spread function is not necessary for enhancing ultrasound image quality by deconvolution.

TL;DR: The experimental results show that all four configurations realized powder microfeeding and dosing but the characteristics, in terms of minimum flow rate, dependence on voltage amplitude and uniformity of dose varied considerably.

TL;DR: The obtained results show that the propagation velocity has the same behaviour of the saccharose concentration, putting in evidence the possibility of monitoring the process state by measuring the ultrasound propagation velocity.

TL;DR: Finite element simulations and results of experiments conducted under well-controlled conditions in a water tank on a series of seeds indicate that the seeds can be detected at any orientation with VA, whereas pulse-echo ultrasound is very sensitive to the seed orientation.

TL;DR: Results show that ultrasonic vibration significantly reduces the sliding friction force, and the texture of the contact surface of the food affects the intensity of ultrasonic transportation effects.

TL;DR: Results indicate that high frequency ultrasound is capable of measuring enamel thickness to an accuracy of within 10% of the total enamel Thickness, whereas currently there is no clinical tool available to measureEnamel thickness.