For quantum (q-deformed) groups the "left" and "right" three-dimensional complex vector-parameters have been introduced which obey to Fyodorov's simplest composition law. The commutation relations for quantum parameters have been obtained, and the quantum matrix of spatial rotation has been constructed.
The ground state of biexciton in quantum small-radius dots has been registered for the first time in experiments using selective mono- and bichromatic laser pumping. It has been found that in accordance with theoretical predictions the biexciton binding energy is positive and increases with decreasing size of the dot. (In cooperation with Kaiserslautern University, Germany and Arizona University, USA.)
The phenomenon of controlled focusing of ultrasonic beams in electro-strictional ferroelectric ceramics under the action of an inhomogeneous electric field of special configuration has been detected for the first time.
An important role has been established of steric factors in the formation of vibrational spectra of carbohydrates which determine differences in vibrational energy localization on the molecule skeleton at close or coinciding frequencies of normal vibrations. (In cooperation with Polish Academy of Sciences.)
The effect of the forbidden gap increasing (up to 40 %) due to quantum size effect for multilayer semiconductor/polymer structures fabricated by the successive vacuum evaporation has been established.
A method for measuring the complex nonlinear constants of waveguide films with the third order nonlinearity based on the analysis of the space distribution of electromagnetic field of a light beam reflected from the prism-film coupler is developed and realized in experiments.
Methods and means have been developed to improve the interferometric stability of holographic recording systems allowing relief-phase recording of interference structures to be performed on silver-free recording media by using coherent radiation in the visible spectrum rage. Experimental samples of reflective holograms were produced with the diffraction efficiency up to 50% in the spatial frequency range of 300--500 lines/mm.
The effective wave-front reversal (WFR) of free-lasing radiation in four-wave interaction has been realized in thin oriented liquid crystal (LC) layers activated with dyes. It has been found that a substantial increase in the WFR effectiveness occurs when the LC temperature approaches the temperature of the LC phase transition to isotropic state.
The physical and mathematical models have been developed for synthesis of intermetallic compounds on metal and semiconductor surfaces in chemically active liquid medium under the action of pulsed laser radiation. It is shown that under conditions of high-power pulsed laser irradiation the formation of shock waves in the liquid medium results in the considerable increase of chemical reaction rate and synthesis of complex semiconductor compounds of the CuInS type.
A technological process for formation of anodic aluminium oxide with through pores with the cell size of more than 0.4 mm has been developed. The grain formation process in molybdenum and vanadium films 100--300 nm thick deposited on such material was studied. It has been demonstrated that, other conditions being equal, micro- and nano-surface roughness exerts a major influence on the grain size in the course of thin-film coating deposition on aluminium oxide. A method has been proposed to form matrix autoemission structures with nanometer sizes of emission regions and its practical suitability was demonstrated.
A technology of parametric modelling of the design objects in the engineering intellectual geometry modelling has been developed, and the experimental version of the system based on this technology has been worked out. The system provides the interactive mode of creation, edition and parametrization of draft models of details and assemblies without participation of a programmer.
Effective algorithms for the single- and two-machine scheduling problems are proposed, and the NP-hardness for a number of such problems is established. In particular, a new class of scheduling problem was investigated where jobs are processed in batches and delivered to the customer together upon the completion time of the last job in the batch.
The fundamentals of a theory and a methodology of the engineering design of electromagnetic tablets for input of graphics information into computer using a nonius method of the measurement of coordinates were developed. On this base a number of high precision input devices with characteristics of the best world products has been designed, and the production of the devices was arranged.
An algorithmic and program model of phonemic speech recognition has been worked out. The phonemic approach to speech recognition provides the solution of one of the most complicated task of designing an intellectual interface -- converting the oral speech into the written text. The theoretical value of this approach is in the application of microsegmental analysis through synthesis. The practical value of the model lies in the creation of programming devices solving for the first time the task of speaker- and vocabulary-independent recognition of large massive with a large degree of reliability.
A general scheme based on the special representation of some semigroups in functional spaces for investigating the 'input-output' operator of wide class of the evolutionary systems has been developed. The stability, controllability and stabilization criteria for multiparameter discrete and difference-differential systems have been given as special realizations of proposed scheme.
The complete description of the joint allocation of the Lyapunov characteristic exponents, the exponential indices, the Vinograd central and the Bohl general exponents on the set of ordinary linear differential systems with coefficients bounded on the positive semi-axis is obtained. It allows one to establish an interconnection between the stability (or instability) of differential systems under different classes of perturbations.
An obstruction to the Hasse principle for the Brauer groups of function fields of wide class of algebraic varieties such as products of the Severi--Brauer varieties and products of smooth projective quadrics was computed. It was founded the conditions under which the Hasse principle for the Brauer groups of function field of a given variety of the above type is valid.
The methods for designing and analysis of the main types of bit-level systolic arrays and the methods for mapping of iterative algorithms of linear algebra into fixed size systolic arrays are proposed. It allows one to design the time-optimum special-purpose systolic arrays for the solution of many problems of numerical analysis and signal processing when the very fast computation are required.
A self-consistent theory of autonomous and nonautonomous laser systems with regards to vector character of electromagnetic field was developed and its feasibility to the investigation of nonlinear dynamics of such systems was demonstrated. There were found such new polarization dynamic phenomena in laser as the autovibrations of radiation polarization parameters, the parametric polarization resonance, and the increase of rotation frequency of polarization azimuth at periodical modulation of anisotropy directions and others.
With the aim to optimize the operating regimes of high-intensity vacuum ultra-violet resonance radiation sources by using the intracavity laser spectroscopy method, the dynamics of high-current pulsed electric discharge in the closed volume in nobel gas (helium, xenon) under lowered pressure has been ascertained, the role of evaporated material form a quartz tube wall on a local thermodynamic equilibrium fulfillment and levels populations of gas medium species has been elucidated.
The decay parametric instability of a stimulated forward scattering l0 --> l1' + s was investigated. It is shown that decay conditions for this process are fulfilled for a pair of space points in a two-dimensional inhomogeneous plasma, that is the cause of excitation of the coherent parametric phenomenon -- the absolute instability.
In terms of the earlier proposed model, implying the existence of bistable oxygen sublattice in the oxide HTSC compounds, the experimentally observed temperature hysteresis of ultrasonic wave distribution rate in such compounds has been interpreted. It is shown that the hysteresis is specified by the interaction of metastable oxygen sublattice with the basic lattice resulting in the change of elastic constants of the latter and, as a consequence, in bistable behavior of the ultrasonic wave over a wide temperature range (60--270 K).
A method of automated analysis and indexing of texts in a natural language through the terms of a standard vocabulary-tezaurus which uses the base of logical formulae of the bases/fragments of words to recognize notions has been developed and implemented via software.
Algorithms and methodology for visual software design, coding and testing on the basis of unified program models and general approach to unit, integration and regression testing have been developed.
The functioning algorithms, language interface and software for data-searching systems with the bases of full-text documents of heterogeneous structure containing texts, images and structured alphabetic-numeric data have been developed.
The optical and electronic information channel capacities are considered and compared on the basis of Bose--Einstein and Fermi--Dirac statistics. It is shown that quantum effects play an important but essentially different roles for both types of channels at information rate ³1012 bit/s, i.e. the level reachable by electronic supercomputers up to date. At information rate by 1013 bit/s the energy price for transmitting/processing one bit of information is 3--4 order of magnitude less for photon (boson) channels as compared with electronic (fermion) ones. A general expression for fermion information channel capacity has been obtained in the case of arbitrary dimensionality of signals. This expression results into the classical Shennon formula at low power of input signals.
The propagation of gaussian light beams in the vicinity of the optical axes of the biaxial gyrotropic crystals is investigated. The possibility of focusing and diffractionless propagation of light is shown.
The concept of 'spatial amplification' which is based on transverse effects in optical bistability is proposed and experimentally proved. With the help of 'spatial amplifier' the possibility is experimentally shown to detect weak optical signals with the power that is 107 -- 108 times less than the power of noise.
Source: "Main Results of Fundamental Research.1992--1993". Eds. A.M.Goncharenko and N.N.Kostyukovich. Academy of Sciences of Belarus, Minsk, 1994
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