Purpose: This study aimed to first investigate synchronous (SYN) versus asynchronous (ASY) mode of propulsion and, second, investigate the wheel camber effects on sprinting performance as well as temporal parameters. Method: Seven wheelchair basketball players performed four maximal eight-second sprints on a wheelchair ergometer. They repeated the test according to two modes of propulsion (SYN ...

BACKGROUND It has been suggested that a higher intra-individual variability benefits the motor learning of wheelchair propulsion. The present study evaluated whether feedback-induced variability on wheelchair propulsion technique variables would also enhance the motor learning process. Learning was operationalized as an improvement in mechanical efficiency and propulsion technique, which are th...

NASA researchers recently demonstrated successful real-time fault detection and isolation of a virtual reusable launch vehicle main propulsion system. Using a detailed simulation of a vehicle propulsion system to produce synthesized sensor readings, the NASA team demonstrated that advanced diagnostic algorithms, running on flight-like computers, can, in real time, successfully diagnose the pres...

Full scale measurements of the propulsion power, ship speed, wind speed and direction, sea and air temperature, from four different loading conditions has been used to train a neural network for prediction of propulsion power. The network was able to predict the propulsion power with accuracy between 0.8-2.8%, which is about the same accuracy as for the measurements. The methods developed are i...

It has been shown that mature oocytes injected with nuclei from round spermatids collected from mouse testis can generate normal offspring and that round spermatids can develop in vitro. An undetermined issue is whether spermatids developed in vitro are capable of generating fertile offspring by nuclear injection into oocytes. Herein, we report the production of normal and fertile offspring by ...

Vampyroteuthis infernalis is a cosmopolitan cephalopod that lives in the oxygen minimum layer between 600 and 800 m depth. Morphometric and physiological studies have indicated that V. infernalis has little capacity for jet propulsion and has the lowest metabolic rate ever measured for a cephalopod. Because fin swimming is inherently more efficient than jet propulsion, some of the reduction in ...

It is vital to maintaining a constant direction during locomotion. Turning in walking is triggered by the impulse from the leg located outside its rotation axis. Then, the centre of gravity is relocated in the direction of an inside limb [1]. It is commonly believed that similar correlation can be observed in swimming. Greater propulsion forces produced by the right limbs cause turning left. Th...

Most of the long-reach inspection devices developed so far have a limitation in the reduction of their diameter when their length is increased. This limitation is due to the technology used to provide the actuation to the system. The use of water-jet as propulsion source is promising to be a solution for this problem. Currently different devices use water-jet as propulsion. However, none of the...

The U.S. Vision for Space Exploration calls for NASA to undertake human exploration of the Moon and Mars. This endeavor must be performed in an affordable manner in order to be successful. This thesis outlines a series of affordability strategies that could be considered as part of the Vision for Space Exploration. Analyses of specific options for affordable human Moon and Mars missions along w...

A detailed examination of the physics principles that underlie the operation of the GDM fusion confinement system is carried out in order to assess its transformation to a potential propulsion device. With an ion collision mean free path much shorter than its length, the plasma in GDM behaves like a fluid, and its escape from the chamber is analogous to the flow of a gas into vacuum from a vess...