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An approach is presented to describe the mechanical behavior of the shape memory materials. On the one hand it uses the basic concepts of the structure-analytical theory proposed by V.A.Likhachev and V.G.Malinin which are the formulation of the constitutive equations of the phase transformation and martensitic unelasticity for micro regions and the orientation averaging of micro strains to obtain the macro strain. On the other hand the averaging procedure is arranged in a way to account for the crystal symmetry of the material. Results are presented of the computer simulation of pseudoelasticity, shape memory effect and active straining of a shape memory material with a thermoelastic martensitic transformation. These are stress-strain diagrams at various temperatures, temperature dependencies of the martensitic unelastic strain. All the results show good qualitative agreement with the experiments in which dislocation plasticity does not play a significant role.

We carry out a comparative analysis of performances of a cellular communication system with adaptive modulation and coding (AMC) and a system with power control (PC). It is shown that the performance of an AMC system is higher than the performance of a PC system for an arbitrary probability density function of the signal fading. To achieve identical throughputs of the two systems, the mean transmitted power for PC must be greater than that for AMC. For identical mean transmitted powers, the throughput of an AMC system is always greater than that of a PC system. We consider code division multiple-access (CDMA) systems with arbitrary numbers of fading time-taps (paths), having a statistically independent Rayleigh fading of signals from path to path. The influence of self-interference on AMC and PC performance is studied. This self-interference results from the nonideal path separation in the receiver.

We report measurements of the self-focusing and self-deflection of argon ion laser light for PLZT 11/65/35 ceramic samples. The results are interpreted in terms of a nonlinear refractive index and a thermal lens model. The far-field patterns of a thermal lens and self-deflected light beams are presented.

We report measurements of selftransparency effects in PLZT 8/65/35 ceramics for various wavelength of laser radiation λ = 0. 5+6 νm. The results are interpreted in terms of thermally induced phase transitions, thermal lens and photorefraction in PLZT. Optimal conditions for the light-by-light control in PLZT 8/65/35 are achieved and discussed.

We report the first observation and investigation of the non-linear effect of light scattering in PLZT ceramics. The presented experimental results of light-induced transparency of the strongly scattering state in polarized PLZT 8/65/35 ceramics are explained in terms of phase transition to weak scattering state induced by Ar+ laser beam.