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General relativity describes the physical force of gravity and its relation with the space-time structure. The fundamental physical insight behind the theory of general relativity is that the effects of acceleration cannot be distinguished from those of gravity. The presence of matter changes the geometry of space and acceleration is experienced in relation to that geometry. In particular, the geometry of space and time is dynamically governed by physical laws that are not independently given. Such a case is the fluid turbulence which remained unexplained for over fifty years within the framework derived from the classical Navier-Stokes theory. The physical and mathematical problem of the genuine turbulence remains an unsolved one. This paper considers the turbulence as a manifestation of non-Newtonian behavior induced by the gravity-like accelerations at the beginning of motion. The fluid particles with high accelerations exhibit in wall-bound flows with large Reynolds number a sort of structure-less, background turbulence. It is shown that the relativistic viewpoint may solve the present paradigmatic crisis of turbulence. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes a heuristic algorithm for near-optimal handling of the redundancy in robot mechanisms, applied to a 3D scanning platform consisting of a 6-DOF articulated robot arm which moves a laser sensor around a workpiece placed on a rotary table. The proposed method handles both static constraints, like avoiding joint limits, kinematic singularities or collisions, modelled using a configuration map viewed as a grayscale image, and dynamic constraints like velocity and acceleration. The algorithm is compared with Dijkstra algorithm, which gives the optimal solution, but is very slow, and with two other heuristics which are very fast, but give suboptimal solutions. [Copyright &y& Elsevier]