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Jet Methods in Time-Dependent Lagrangian Biomechanics
In this paper we propose the time-dependent generalization of an `ordinary'
autonomous human biomechanics, in which total mechanical + biochemical energy
is not conserved. We introduce a general framework for time-dependent
biomechanics in terms of jet manifolds associated to the extended
musculo-skeletal configuration manifold, called the configuration bundle. We
start with an ordinary configuration manifold of human body motion, given as a
set of its all active degrees of freedom (DOF) for a particular movement. This
is a Riemannian manifold with a material metric tensor given by the total
mass-inertia matrix of the human body segments. This is the base manifold for
standard autonomous biomechanics. To make its time-dependent generalization, we
need to extend it with a real time axis. By this extension, using techniques
from fibre bundles, we defined the biomechanical configuration bundle. On the
biomechanical bundle we define vector-fields, differential forms and affine
connections, as well as the associated jet manifolds. Using the formalism of
jet manifolds of velocities and accelerations, we develop the time-dependent
Lagrangian biomechanics. Its underlying geometric evolution is given by the
Ricci flow equation.
Keywords: Human time-dependent biomechanics, configuration bundle, jet
spaces, Ricci flowComment: 13 pages, 3 figure
Near-lunar proton velocity distribution explained by electrostatic acceleration
The observation of parallel ion velocity in the near-lunar wake approximately
equal to external solar wind velocity \emph{can} be explained within
uncertainties by an analytic electrostatic expansion model. The one-dimensional
model frequently used is inadequate because it does not account for the moon's
spherical shape. However, application of a more recent generalization to
three-dimensions of the solution along characteristics predicts higher
velocities, and is probably sufficient to account for the SARA observations on
the Chandrayaan-1 space-craft.Comment: 1 figure, 1 tabl
Gravity stabilized flying vehicle Patent
Hovering type flying vehicle design and principle mechanisms for manned or unmanned us
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