Toroidal equilibrium and Dynamic Stabilization in a Screw Pinch

Stabilization in Dynamic Systems with Varying Equilibrium

System design often explores optimality of performance. What is optimal is, however, often not predefined or static in most cases, because it is affected by the context of operation, such as the environment or external system inputs. In this paper, we formulate the maintenance of optimality of performance in dynamical systems in terms of the standard notion of stabilization. For systems with ob...

An Intelligent Shell for the Toroidal Pinch*

1. I N T R O D U C T I O N LARGE SCALE STABILITY in a reversed field pinch is generally achieved by surrounding the plasma with a close-fitting highly conducting shell. Macroscopic instabilities must drive flux through the shell and this sets up eddy currents which generate an opposing field distribution. On short time scales the flux through the shell remains fixed and growth of the unstable m...

Study of bone-screw surface fixation in lumbar dynamic stabilization.

BACKGROUND We aimed to use the animal model of dynamic fixation to examine the interaction of the pedicle screw surface with surrounding bone, and determine whether pedicle screws achieve good mechanical stability in the vertebrae. METHODS Twenty-four goats aged 2-3 years had Cosmic ® pedicle screws implanted into both sides of the L2-L5 pedicles. Twelve goats in the bilateral dynamic fixatio...

Dynamic equilibrium mechanism for surface nanobubble stabilization.

Recent experiments have convincingly demonstrated the existence of surface nanobubbles on submerged hydrophobic surfaces. However, classical theory dictates that small gaseous bubbles quickly dissolve because their large Laplace pressure causes a diffusive outflux of gas. Here we suggest that the bubbles are stabilized by a continuous influx of gas near the contact line, due to the gas attracti...

Modeling the Parker instability in a rotating plasma screw pinch