Background. This study aimed to analyze core muscle fatigue effects on the kinematic parameters change during volleyball jump serve. Methods. The participants were sixteen experienced male volleyball players with average age, height, and body weight of 24.6 ± 1.8 years, 1.85 ± 1.6 m, and 79.5 ± 3.5 kg, respectively. This study utilized two high-resolution video cameras, a drone video, a lactat...

In CAVE-like environments human locomotion is significantly restricted due to physical space and configural constraints. Interaction techniques based upon stepping in place have been suggested as a way to simulate long range locomotion. We describe a new method for step detection and estimation of forward walking speed and direction in an immersive virtual environment. To calibrate our system a...

The nonlinear responses of ship rolling motion characterized by a roll damping moment are of great interest to naval architects and ocean engineers. Modeling and identification of the nonlinear damping moment are essential to incorporate the inherent nonlinearity in design, analysis, and control of a ship. A stochastic nonparametric approach for identification of nonlinear damping in the genera...

Here we explain a much avoided phenomenon in the evolution of speed sports for men and women: The world records in running tend to be set by black athletes and in swimming by white athletes. We show that this phenomenon is predictable from physics. Locomotion is a ‘falling-forward’ cycle, in which body mass falls forward and then rises again. Mass that falls from a higher altitude falls faster,...

The practical use of realistic models in bioelectromagnetism is limited by the time-consuming amount of numerical calculations. We propose a method leading to much higher speed than currently available, and compatible with any kind of numerical methods (boundary elements (BEM), finite elements, finite differences). Illustrated with the BEM for EEG and MEG, it applies to ECG and MCG as well. The...

Experiments were performed on a neuro-musculo-mechanical model of a lamprey, to explore the strategies for controlling swimming speed. The muscle component of the model was based on previous experiments on isolated lamprey muscle. The patterns of muscle activation were those found in EMG studies on swimming lampreys. The fluid mechanics were modelled with G.I. Taylor's simplification. Tail beat...

Waves of spanwise velocity imposed at the walls of a plane turbulent channel flow are studied by Direct Numerical Simulations. We consider sinusoidal waves of spanwise velocity which vary in time and are modulated in space along the streamwise direction. The phase speed may be null, positive or negative, so that the waves may be either stationary or traveling forward or backward in the directio...

This paper puts forward a fault isolation method for nonlinear dynamic systems. The method based on nonlinear observers and using parameter partition. It fits many kinds of nonlinear dynamic systems and its fault isolation speed is satisfying.

In this paper we investigate residue number system to binary converter algorithms for special moduli sets. A new five moduli set proposed is shown to exhibit high speed forward and reverse conversion properties. The architectures are memoryless and area efficient.

in this paper, the temperature distribution in workpiece and microstructure of welded zone in friction stir welding of aluminum 1100 alloys and the effect of the tool rotational speed on these parameters have investigated experimentally. also feed forward back propagation neural network has been used to predict the temperature of the workpiece during the welding process by considering the proce...