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The number of deaths caused by traffic accidents remains high, in spite of the development of many kinds of safety technologies. It is difficult to absorb the impact energy sufficiently in many cases. We suggested that the impact energy can be further absorbed by adjusting the deformation resistance of the material of the structure instantaneously. Furthermore, we developed an impact-reduction setup...
During coagulation, blood changes from liquid to gel, and the clot viscoelastic properties continue modifying until fibrinolysis. Ultrasound (US) was used in this work to trace the time-changing shear modulus, μ, during plasma clotting, based on the vibration signature induced by an impulsive acoustic radiation force (iARF) on a sphere embedded in a plasma sample along its clotting process induced...
Acoustic droplet vaporization (ADV) is a process when a droplet is converted into a gaseous bubble under ultrasound (US) stimulation. Our previous study has shown that the mechanical force generated by ADV can release drugs and disrupt vessels. It would result in the streaming intact droplets leaking into tissue. In addition, the intact droplets may occur ADV process by subsequent US stimulation....
Elasticity values reported by shear wave elastography techniques for Breast tissue/mass are a combination of elasticity and viscosity at the frequency with peak shear wave energy; thus, resulting in overestimation of tissue elasticity. To better estimate shear elasticity and to understand the role of shear viscosity in suspicious breast masses at different frequencies, the frequency dispersion of...
Contact manipulation using a micropipette is widely used for cell culture and evaluation. However, the operation efficiency and the damage on the cells depend on the individual skills. A technique for manipulating a micro biological material with high accuracy and selectivity is required. Our group has been investigating noncontact ultrasonic manipulation techniques using acoustic standing wave. In...
Microbubbles (MBs) are widely used in clinical site as contrast agents in ultrasound imaging due to its eminent responsiveness to several MHz band. In recent years, ultrasound drug delivery system (DDS) using MBs are widely researched to achieve selective medication to the targeted diseased part. In the condition of high number density of bubbles to enhance the performance of DDS, it is essentially...
Microbubbles (MBs) are widely used in clinical site as contrast agents in ultrasound imaging due to its eminent responsiveness to several MHz band ultrasound. In recent years, ultrasound drug delivery system (DDS) using MBs are widely researched to achieve selective medication to the targeted diseased part. In the condition of high number density of bubbles to enhance the performance of DDS, it is...
Imaging technologies that allow assessment of the elastic properties of soft tissue provide clinicians with an important asset for several diagnostic applications. A quantitative measure of stiffness can be obtained by shear-wave (SW) elasticity imaging, a method that uses acoustic radiation force to produce laterally-propagating shear waves that can be tracked to obtain the velocity, which in turn...
In transversely isotropic (TI) materials, mechanical properties differ along versus across the axis of symmetry (AoS). The degree of these directional differences has been interrogated by ultrasound-based measures of shear wave velocity (SWV) and ARFI peak displacements (PD) acquired along versus across the AoS. When performed using a conventional linear array transducer, such measurements require...
Although we have already experimented to bend a thin catheter with acoustic radiation force using a single transducer, it is necessary to develop a method to bend a catheter to an arbitrary direction because installation position of ultrasound transducers on body surface is limited to adopt to various shape of in vivo blood vessel. Therefore, we examined to bend the thin catheter to the perpendicular...
Pulling optical force discovered recently in the theory and experiment has drawn great attention owing to its counterintuitive nature and promising applications. Pulling force originates from the enhanced forward light scattering that in accordance with the momentum conservation conveys light momentum to particles in the backward direction. The amplified forward scattering is achieved through the...
Ultrasonic welding of carbon paper and proton exchange membrane (PEM) for membrane exchange assemblies (MEAs) of fuel cells (FCs) is a viable technology to replace hot-pressing, which may be time consuming and energy inefficient. Ultrasonic spot welding of carbon paper and PEM is investigated in order to understand the bonding mechanisms and obtain the suitable processing parameters. Micrographs of...
Lightweight structures find more and more applications in both vehicle and ship industries. To meet a growing demand, a variety of different types of joisted panels have been developed during the last few decades. One of the problems to deal with is the assessment of the acoustic performances of such panels once they are already mounted in their final place. In this case, it can be of importance to...
The HUE tablet, presented in this work, leverages ultrasonic friction reduction and electrovibration to enhance the dynamic friction range of its surface. Prototypes using a single friction-modulation approach are numerous, but none offer the option to perform friction-switching above and below a base level on a single platform. In applications involving active touch, the ability to dynamically change...
The objective of the project is to develop a model for the capacitive ultrasonic transducer described in the Ladabaum et al., [1] paper. The main element of the transducer is a metalized silicon nitride membrane suspended on a rigid support above a heavily doped silicon bulk. The cavity under the membrane is vacuumed. When a voltage is applied between the metalized membrane and the bulk, the Coulomb...
We report an approach to controlling friction forces on sliding human fingertips in order to produce simultaneous vibrations across an exceedingly broad range of tactile, audible, and ultrasonic frequencies. Vibrations in the skin can be felt directly by the fingertip, and vibrations in the air can be heard emanating from the proximity of the finger. We introduce and detail an experimental apparatus...
The human body represents the most important topic for many researchers. In our days, the science complexity demands the involvement of many resources and the coordinated team work of doctors, engineers, and other specialists. In the case of dental medicine, due to the nature of teeth material, their dimension and geometrical position, very important problems, like fractures, cannot be studied with...
Paper presents analytical and numerical results of evaluation utmost levels of vibroactivity for sources arising out of electrodynamical interaction of currents flowing through current-carrying elements in different electrotechnical devices and systems. It has shown that values of forces, arising out of such interaction, cannot be informative criteria for evaluations of such sources' vibroactivity...
Piezoelectric vibration cell penetrating technology has been proved to be a useful technology in biomanipulation field. It helps biomedical operators obtain a slight damage to cells and get a high cell injection success rate in manipulation. But conventional piezo-driven injection equipments still have some problems limit their applications. Large scale harmful lateral vibration and complex manipulation...
Locking devices play an important role in robots and assist suits in terms of energy management and miniaturization. In this work, we develop a new locking device for a flat belt that can lock the belt at arbitrary positions and has a simple design that requires no driving parts. According to a mechanical analysis of a flat, overlapped-belt structure, the locked and unlocked states of a flat belt...
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