Evolutionary Synthesis of Dynamical Object Emulator Based on RBF Neural Network

The combination of Genetic Algorithms (GAs) and Artificial Neural Networks (ANNs) has already resulted in researchers advancing in quite a few real world applications but it is in control that this alliance yields much appreciable benefit. The paper reports a Radial Basis Function (RBF) network training technique which joins together global strategy of GAs and a local adjusting procedure typical for RBF networks. While activation function window centres and widths are processed via a "slow" numeric GA, output-layer neurone synaptic weights are defined by a "fast" analytical method. The technique allows to minimize not only the network hidden-layer size but also the pattern set required for training the adequate dynamical object neuroemulator

Amplitude-Frequency Characteristic of a Neural Control Based DC Drive

The paper interprets characteristics of a neural-control-based DC servodrive in terms of the classical theory of automatic control. It also touches on the problem of choosing training patterns to synthesize a nonlinear PID-controller with a desired amplitude-frequency characteristic and analyses the efficiency of using for this purpose input signals in form of a step function and a harmonic one. Synthesis of the neurocontroller has been performed within the framework of a three-layer perceptron. To train it, a genetic algorithm has been developed

On Spin Calogero-Moser system at infinity

We present a construction of a new integrable model as an infinite limit of Calogero models of N particles with spin. It is implemented in the multicomponent Fock space. Explicit formulas for Dunkl operators, the Yangian generators in the multicomponent Fock space are presented. The classical limit of the system is examined

Phase coherent transport in (Ga,Mn)As

Quantum interference effects and resulting quantum corrections of the conductivity have been intensively studied in disordered conductors over the last decades. The knowledge of phase coherence lengths and underlying dephasing mechanisms are crucial to understand quantum corrections to the resistivity in the different material systems. Due to the internal magnetic field and the associated breaking of time-reversal symmetry quantum interference effects in ferromagnetic materials have been scarcely explored. Below we describe the investigation of phase coherent transport phenomena in the newly discovered ferromagnetic semiconductor (Ga,Mn)As. We explore universal conductance fluctuations in mesoscopic (Ga,Mn)As wires and rings, the Aharonov-Bohm effect in nanoscale rings and weak localization in arrays of wires, made of the ferromagnetic semiconductor material. The experiments allow to probe the phase coherence length L_phi and the spin flip length L_SO as well as the temperature dependence of dephasing.Comment: 22 pages, 10 figure