Motion Driven by Strain Gradient Fields

Motion Driven by Strain Gradient Fields.

A new driving mechanism for direction-controlled motion of nano-scale objects is proposed, based on a model of stretching a graphene strip linked to a rigid base with linear springs of identical stiffness. We find that the potential energy difference induced by the strain gradient field in the graphene strip substrate can generate sufficient force to overcome the static and kinetic friction for...

Vortex Motion Driven by a Background Vorticity Gradient

The motion of self-trapped vortices on a background vorticity gradient is examined numerically and analytically. The vortices act to level the local background vorticity gradient. Conservation of momentum dictates that positive vortices (“clumps”) and negative vortices (“holes”) react oppositely: clumps move up the gradient, whereas holes move down the gradient. A linear analysis gives the traj...

Nonsingular stress and strain fields of dislocations and disclinations in first strain gradient elasticity

The aim of this paper is to study the elastic stress and strain fields of dislocations and disclinations in the framework of Mindlin’s gradient elasticity. We consider simple but rigorous versions of Mindlin’s first gradient elasticity with one material length (gradient coefficient). Using the stress function method, we find modified stress functions for all six types of Volterra defects (dislo...

Existence and Measurability of the Solution of the Stochastic Differential Equations Driven by Fractional Brownian Motion

Matching Images by Comparing their Gradient Fields

We present a simple yet powerful method to per form point to point matching between two images The method uses an evidence measure whose value for a given displacement re ects both the similarity between two locations and the con dence in a correct match The measure is based on the gradient elds of the im ages and can be computed quickly and in parallel Accumulating the evidence measure for di ...