In this paper the problem of reliable along-track velocity estimation is addressed. It is known that the neglection of across-track accelerations can bias the estimates of along-track velocities, but up to now it is unknown which vehicle accelerations appear in real traffic scenarios. On this account an experiment to measure accelerations was conducted. The measurement results, which are presen...

Background: Little kinematic or kinetic information is available to understand risks associated with water skier falls. The present study assessed accelerations during low-speed falls and then contrasted these data against information obtained from automotive crash tests to better delineate risk of injury. The goal was to establish baseline impact information for low-speed falls during water sk...

Intralimb kinetics of the paw-shake response (PSR) were studied in four spinal, adult cats. Using rigid body equations of motion to determine the dynamic interactions between limb segments, knee and ankle joint kinetics were calculated for the steady-state cycles as defined in the preceding paper. Hindlimb motion was filmed (200 frames/s) to obtain knee and ankle kinematics. Responses of flexor...

During orbital spaceflight, the acceleration of gravity is reduced from one-G on the Earth’s surface to about 10–6-G in orbit. Nevertheless, the head accelerations associated with changing direction and with turning are unaffected. Therefore, the body must selectively adapt to the relative absence of gravity. As a result of this reorganization, astronauts frequently exhibit difficulty with bala...

Higher–dimensional theories imply that some constants, such as the gravitational constant and the strength of the gauge–couplings, are not fundamental constants. Instead they are related to the sizes of the extra–dimensional space, which are moduli fields in the four– dimensional effective theory. We study the cosmological evolution of the moduli fields appearing in brane world scenarios and di...