The problem of generation and existence of large-scale vortices in the ionosphere is analyzed in this paper. Some exact solutions of the magneto-hydrodynamic (MHD) equations have been found and new invariants have been constructed allowing to descover mechanisms of generation of large-scale vortices and planetary waves in the electroconducting atmosphere under the action of non-conservative Cor...

We analyze the scepticism on the hydrodynamic turbulence in Keplerian astrophysical disks expressed in Balbus and Hawley 2006 and show the failure of arguments of the paper. Recently Balbus and Hawley 2006 (BH06) have shown time-dependent three-dimensional nonlinear wave solution when considering a local Keplerian flow. Authors have demonstrated that the linear wave solution derived in Johnson ...

We consider planar and spatial autonomous Newtonian systems with Coriolis forces study the existence of branches periodic orbits emanating from equilibria. investigate both degenerate nondegenerate situations. While Lyapunov's center theorem applies locally in nondegenerate, nonresonant context, our result provides a global answer which is significant also some cases. apply abstract results to ...

Motion observed in a rotating frame of reference is generally explained by invoking inertial forces. While this approach simplifies some problems, there is often little physical insight into the motion, in particular into the effects of the Coriolis force. To aid in the understanding of three-dimensional inertial forces, motion on a rotating sphere is considered from the points of view of an in...

In this paper we present two controllers for robots that combine terms for the compensation of gravity forces, and the forces of friction of motors and gearboxes. The Low-Friction Zero-Gravity controller allows a guidance of the robot without effort, allowing small friction forces to reduce the free robot motion. It can serve to aid users providing kinesthetic demonstrations while programming b...

The phase difference between the oscillations of Coriolis flowmeter (CFM) arms is main experimentally observed parameter during measurements liquid flow rates in pipelines. Usually, steady-state and known dependences rate measured shift are assumed. However, these conditions met with a sufficient accuracy only for homogeneous single-phase flows. For inhomogeneous multiphase flows, correction ne...

We present an experimental analysis of the effects of gravity level on the formation and rise dynamics of bubbles. Experiments were carried out with millimeter-diameter bubbles in the hypergravity environment provided by the large-diameter centrifuge of the European Space Agency. Bubble detachment from a nozzle is determined by buoyancy and surface tension forces regardless of the gravity level...

A global, bi-homogeneous, observer for a class of 1-DOF mechanical systems with Coriolis and centrifugal forces, dry viscous frictions non-vanishing bounded uncertainties/perturbations is proposed, ensuring predefined upper bound convergence time. The options acceleration are discussed in simulation example.

As a countermeasure to the debilitating physiological effects of weightlessness, astronauts could live continuously in an artificial gravity environment created by slow rotation of an entire spacecraft or be exposed to brief daily "doses" in a short radius centrifuge housed within a non-rotating spacecraft. A potential drawback to both approaches is that head movements made during rotation may ...

The centripetal force generated by a rotating space vehicle is a potential source of artificial gravity. Minimizing the cost of such a vehicle dictates using the smallest radius and highest rotation rate possible, but head movements made at high rotation rates generate disorienting, nauseogenic cross-coupled semicircular canal stimulation. Early studies suggested 3 or 4 rpm as the highest rate ...