In many scientific and medical applications wavefront-sensorless adaptive optics (AO) systems are used to correct the wavefront aberration by optimizing a certain target parameter, which is nonlinear with respect to the control signal to the deformable mirror (DM). Hysteresis is the most common nonlinearity of DMs, which can be corrected if the information about the hysteresis behavior is prese...

Mechanisms of energy dissipation during solid-solid and solid-liquid friction are discussed. A conservative van der Waals adhesion force, when combined with surface imperfectness, such as deformation, leads to adhesion hysteresis (AH). When an asperity slides upon a substrate, the substrate is subjected to a loading-unloading cycle, and energy is dissipated due to the AH. Another mechanism, whi...

Atomic scale dissipation is of great interest in nanomechanics and atomic manipulation. We present dissipation measurements with a linearized, ultra-small amplitude atomic force microscope which is capable of measuring dissipation at chosen, fixed separations. We show that the dynamic dissipation in the noncontact regime is of the order of a few 10-100 meV per cycle. This dissipation is likely ...

A finite element approximation of the thin film limit for a sharp interface bulk energy for martensitic crystals is given. The energy density models the softening of the elastic modulus controlling the low-energy path from the cubic to the tetragonal lattice, the loss of stability of the tetragonal phase at high temperatures and the loss of stability of the cubic phase at low temperatures, and ...

Suucient conditions of existence and global asymptotic stability of a limit cycle induced by a relay with hysteresis feedback in a linear time-invariant stable system are derived. The criterion is based on inspection of the open loop step response, combined with estimations of certain measures of its variance. Unlike the well-known describing functions method, the proposed approach yields a rig...

Uniaxial tension-compression fatigue behavior of 3-mol%yttria-stabilized tetragonal zirconia polycrystals was investigated. Hysteresis in the stress-plastic strain curve featured cumulative plastic strain and weakened elastic stiffness. Fracture statistics in terms of cycle-to-failure depends strongly on the maximum stress and less on the stress amplitude. Preexisting processing flaws were iden...

The Direct Torque Control (DTC) is a high-dynamic and high performance control technique for induction motor drives which has been developed in the last two decades [1]-[8] as possible alternative solution to DC servo drives. In direct-torque-controlled adjustable speed drives the motor flux and the electromagnetic torque are the reference quantities which are directly controlled by the applied...

The origins of gate-induced hysteresis in carbon nanotube fi eld-effect transistors are explained and techniques to eliminate this hysteresis with encapsulating layers of methylsiloxane and modifi ed processes for nanotube growth are reported. A combined experimental and theoretical analysis of the dependence of hysteresis on the gate voltage sweep-rate reveals the locations, types, and densiti...

We use the Cellular Potts Model (CPM) to study the contact angle (CA) hysteresis in multiphase (solid-liquid-vapour) systems. We simulate a droplet over the tilted patterned surface, and a bubble placed under the surface immersed in liquid. The difference between bubbles and droplets was discussed through their CA hysteresis. Dependency of CA hysteresis on the surface structure and other parame...