A phase-field model is developed for predicting the polarization switching and domain structure evolution under an applied electric field in ferroelectric polycrystals. The model takes into account realistic grain structures as well as various energetic contributions, including elastic energy, electrostatic energy, and domain wall energy. A hysteresis loop – average polarization as a function o...

The bacterial flagellar motor plays a crucial role in both bacterial locomotion and chemotaxis. Recent experiments reveal that the switching dynamics of the motor depend on the rotation speed of the motor, and thus the motor torque, nonmonotonically. Here we present a unified mathematical model which treats motor torque generation based on experimental torque-speed curves and the torque-depende...

Hard-switching losses in three-level T-type (3LTT) bridge-legs cannot be directly estimated from datasheet energy loss curves, which are given for symmetric two-level half-bridge configurations only. The commutations a 3LTT bridge-leg occur between semiconductors with different blocking voltages and/or current ratings, and involve third semiconductor device the switching transition, contributes...

We present a method coupling multiple switching linear models. The coupled switching linear model is an interactive process of two switching linear models. Coupling is given through causal influence between their hidden discrete states. The parameters of this model are learned via EM algorithm. Tracking is performed through the coupled-forward algorithm based on Kalman filtering and a collapsin...

We present a method coupling multiple switching linear models. The coupled switching linear model is an interactive process of two switching linear models. Coupling is given through causal influence between their hidden discrete states. The parameters of this model are learned via EM algorithm. Tracking is performed through the coupled-forward algorithm based on Kalman filtering and a collapsin...

Switching dynamics of nanoscale ferroelectric capacitors with a radius of 35 nm were investigated using piezoresponse force microscopy. Polarization switching starts with only one nucleation event occurring only at the predetermined places. The switching dynamics of nanoscale capacitors did not follow the classical Kolmogorov-Avrami-Ishibashi model. On the basis of the consideration of two sepa...

the large amount of computation necessary for obtaining time optimal solution for moving a manipulator on specified path has made it impossible to introduce an on line time optimal control algorithm. most of this computational burden is due to calculation of switching points. in this paper a learning algorithm is proposed for finding the switching points. the method, which can be used for both ...

one of the most controversial and unresolved questions in bilingual first language acquisition (henceforth bfla) is whether bilingual children develop one mixed or two independent linguistic systems. many scholars in the lield of bfla arc in tavor of the one-system hypothesis (leopold 1970; swain and wesche, 1975; volterra and tacschner, j 987; grosjean, 1982; tacschncr, 1983: mclaughlin, 1984:...

This paper investigates the problem of switching performance optimal control for continuous-time controller switched systems. An extended bumpless switching technique is proposed via linear quadratic (LQ) optimal control and internal model principle. Then a sufficient condition for guaranteeing the switched closed-loop systems to be stable under bumpless switching is developed. Dwell-time and m...