purpose the objectives of this study include: (1) determination of the attenuation of strike acceleration that tae kwon do sparring safety pads provide from kicks from olympic style tkd fighters, (2) the sex and weight differentiation in acceleration achieved within the thorax model with the roundhouse kicks. methods this prospective, observational study utilized 15 olympic style fighters from ...

More than 100 years ago, Einstein’s special relativity demonstrated that time is a relative notion. The observed rate of a moving clock differs from the rate of a stationary clock. In fact, the observed rate depends on the clock’s velocity. All admissible velocities are bounded by the speed of light. These predictions of special relativity have been verified experimentally in several different ...

On the circular curve, lateral acceleration affects comfort. On the spiral, both lateral acceleration and jerk affect comfort.  The determination of maximum curving speed on the basis of lateral acceleration only is not critical because the lateral acceleration is proportional to the square of speed whereas jerk is proportional to cubic power of speed. The maximum speed on a curve is thus signi...

Movement of open containers containing liquid is considered. A simple linear slosh model is presented that captures the main features of the slosh phenomena. The open-loop acceleration trajectory is calculated using optimal control techniques. Both minimum-time and minimum-energy problems are solved with various constraints on the control and state trajectories. The calculated acceleration prof...

Quality of cardiopulmonary resuscitation (CPR) improves through the use of CPR feedback devices. Most feedback devices integrate the acceleration twice to estimate compression depth. However, they use additional sensors or processing techniques to compensate for large displacement drifts caused by integration. This study introduces an accelerometer-based method that avoids integration by using ...

Two types of acceleration techniques, H-matrix arithmetics and an H-matrix-based variable preconditioning (VP), as well their combination are applied to a linear-system solver in the shielding current analysis cracked high-temperature superconducting film. Although seems be most effective three results computations show that, from standpoint performance, neither VP nor is superior arithmetics. ...