Showing papers in "Ultrasonics in 2014"

TL;DR: After reviewing various techniques the paper concludes which source localization technique should be most effective for what type of structure and what the current research needs are.

TL;DR: Developments in air-coupled transduction and electronics are briefly treated, although the emphasis here is on methods of characterization and inspection, and in overcoming limitations inherent in the use of such a tenuous sound coupling medium as air.

TL;DR: This work reviews the several options available for the use of ultrasound, either to induce a direct physical effect (LIPUS, shock waves), to deliver bioactive molecules such as growth factors, or to transfect cells with osteogenic plasmids; with a main focus on LIPUS as it is the most widespread and studied technique.

TL;DR: Analysis of the mechanical behaviour and energy releasing characteristics of bedded-sandstone with bedding layers in different orientations revealed that the acoustic energy release is considerably higher in dry specimens than that of the saturated specimens at any bedding orientation, whereas specimens with steeply oriented bedding layer showed a comparatively less energy release under both dry and saturated conditions.

TL;DR: This review presents details of various studies on sonophoresis including the latest trends, delivery of various therapeutic drugs, sonphoresis pathways and mechanisms, and outlook of future studies.

TL;DR: This study has yielded a quantitative characterization strategy for fatigue cracks using embeddable piezoelectric sensor networks, facilitating deployment of structural health monitoring which is capable of identifying small-scale damage at an embryo stage and surveilling its growth continuously.

TL;DR: The simulation of ultrasonic assisted turning shows that UAT reduces the stress level on cutting tool during machining as compared to that of in continuous turning (CT) barring the penetration stage, wherein both tools are subjected to identical stress levels.

TL;DR: A mechanistic predictive model for cutting force in RUM of CFRP, based on the assumption that brittle fracture is the dominant mode of material removal, is developed and tested.

TL;DR: This paper proposes a novel method for suppressing the unwanted S0 mode based on the Poisson effect of the material by optimizing the angle of inclination of the equivalent transduction force of the Electromagnetic Acoustic Transducers (EMATs) used for generation and detection purposes.

TL;DR: The total focusing method is compared with the widely used time-reversal MUSIC super resolution technique in terms of its ability to resolve closely spaced scatterers in a solid, and it is shown that for the weak noise situation (SNR>20 dB), time-reaching MUSIC provides significantly enhanced lateral resolution when compared to the totalocusing method, breaking the diffraction limit.

TL;DR: 3D EFIT simulations of guided wave propagation in undamaged and damaged anisotropic and quasi-isotropic composite plates are described and volumetric delamination data acquired via X-ray microfocus computed tomography is directly incorporated into the simulation.

TL;DR: It is demonstrated that the UPV test can be reliably used for the estimation of the strength of CPB samples and was found to be particularly sensitive to fines content.

TL;DR: This paper investigates various types of coded waveforms that could be used for air-coupled ultrasound, using a pulse compression approach to signal processing, and shows that the optimum choice of modulation signal depends on the bandwidth available and the type of measurement being made.

TL;DR: This work suggests a promising use of SH-like guided modes for quantifying shear properties at adhesive interfaces, and shows that such waves can be used for inferring adhesive and cohesive properties of bonds separately.

TL;DR: The UPV test can be suitably exploited for the rapid estimation of the strength and quality of CPB samples even using small samples with concomitant benefits of reducing sample size.

TL;DR: An alternative double-sided arrangement of the periodic stepped pillars for an enlarged pillars' head diameter in the hybrid structure is introduced and the hole diameter is optimized to further lower and widen acoustic band gaps.

TL;DR: Harmonic generation from non-cumulative fundamental symmetric and antisymmetric modes in plate is studied from a numerical standpoint and the phenomenon of mode-interaction to generate sum and difference frequencies is demonstrated.

TL;DR: The results demonstrated the potential of high frequency guided waves for hidden defect detection at critical and difficult to access locations in aerospace structures from a stand-off distance.

TL;DR: A driving and measurement system has been developed to track the resonance of high power transducers and to stabilise their vibration velocity, which has the ability to monitor the operating and performance parameters of the ultrasonic transducers in real time.

TL;DR: This research presents a new technique for nonlinear Rayleigh surface wave measurements that uses a non-contact, air-coupled ultrasonic transducer; this receiver is less dependent on surface conditions than laser-based detection, and is much more accurate and efficient than detection with a contact wedge transducers.

TL;DR: The characteristic features and applications of linear and nonlinear guided elastic waves propagating along surfaces and wedges, and theoretical and experimental results on nonlinear wedge waves in isotropic and anisotropic solids are presented.

TL;DR: A Stiffness Reduction Method (SRM) has been developed that operates within a significantly reduced spatial domain, and has been shown to perform significantly better than ALID, with results confirmed by both numerical and analytical means.

TL;DR: The review shows a great ability of both US techniques to observe setting phenomena and to determine different milestones during the early age formation of CBM's microstructure, indicating that US methods could become standardized in the near future.

TL;DR: Two well-known nonlinear Kalman Filtering algorithms are presented to estimate the location of AE sources in anisotropic panels and it is shown that both EKF and UKF can provide a confidence interval of the estimated AE source location and can account for uncertainty in time of flight measurements.

TL;DR: The development of parallel fiber in cerebella cultures was clearly observed as the contrast in acoustic impedance, without staining the specimen, as the technique is believed to be a powerful tool for biological tissue characterization, as no staining nor slicing is required.

TL;DR: Models suggest that the reflection is a linear superposition of the reflections from each bend segment, such that sharp turns lead to a larger peak-to-peak amplitude, in part due to increased phase coherence.

TL;DR: The observations indicate that periodic shock-emissions from acoustically driven cavitation clouds provide a source for the cavitation subharmonic signal, and that shock structure may be used to study intra-cloud dynamics at sub-microsecond timescales.

TL;DR: The two paths flowmeter has been calibrated and validated on the test facilities for air flow in Shaanxi Institute of Measurement & Testing, and develops timing modules to determine the flight time of the acoustic signal.

TL;DR: When drilling CFRP/Ti stacks using RUM, cutting force, torque, and CFRP surface roughness were lower, hole size variation was smaller, CFRP groove depth was smaller), tool life was longer, and there was no obvious Ti exit burr and CFRp entrance delamination.

TL;DR: Energy analysis of an oscillating isolated spherical bubble in water irradiated by an ultrasonic wave has been theoretically studied for various conditions of acoustic amplitude, ultrasound frequency, static pressure and liquid temperature in order to explain the effects of these key parameters on both sonochemistry and sonoluminescence.