In the ring laser, multiple passage through an active medium may be provided, in contrast to the linear laser, by a running wave. Each of the running waves may be provided generation. Generally, counterpropagating running waves are not similar in the ring laser. They differ in intensity, phase, frequency, polarization. This distinctions are called nonreciprocity. Features of the ring laser for various applications. They allow the development of frequency standards, laser giro, goniometer, analytical instruments. Ring laser offer advantages for linear-angular measurements and measurements of parameters of motion. Ways to optimize the parameters of ring laser are indicated.

Laser radiation has a wide application in molecules Raman lidar control and its concentration measurement in atmosphere under industrial regions for creation people good living conditions. Back scattering vibration Raman lidar equation computer simulation for iodine molecules and its heavy isotopes with YAG-Nd, cuprous vapor and excimer lasers have been made to choose optimal lidar system for studied molecules monitoring in atmosphere. Background stray sunlight power were calculated to determine the minimum molecules concentration at ranging distance up to 6 km.

Metal rolls surface laser testing and PC controlled bad rolls detection system is based on optical comparator for two laser beams normally incident on rotating roll surface. Its operation is in two scattered beams intensities variations consequently to changes in defect passing between beams for certain time duration or simultaneous changes due to random roll vibrations. PC signal filtering and data array statistical treatment allows to get scattering coefficients dispersion histograms with lower maximum and greater dispersion halfwidth for bad rolls.

The effective work of dust-absorber is characterized by the relation of target and entrance concentration of a dust and its dynamics changes and depends, as a rule on a technical condition. The optical tool IVA-3-M, made SPA STROMECOLOGY (NOVOROSSIYSK) according to THAT 21-4861014-12-90, allows to carry out automatic continuous diagnostics of a technical condition of a dust-absorber. In a basis of work of the tool a method integrated light scattering on particles moving in an air flow lays. It is carried out an uniform OIITHKO- electronic unit, which is established directly on a wall entrance and target of gas pipes and its target signal is defined (determined) by mass concentration of a dust. The check and adjustment of the tool IVA-3M was made on the special laboratory stand, carried out as dust air flow closed pipe.

Fast perfection of sensors has caused a significant growth of the usage of the methods of testing, based on the visualization. Among the most popular are the methods of visualization based on registration of the IR radiation of the object under investigation and x-ray examination. An increase of sensors characteristics is putting a demanding task to the development of the optic systems matching parameters of conventional detectors. The paper presents the results of development of some precise lenses, which are used in some complicated applications of thermovision and x-ray projection systems.

The accurate determination of the multielement sample composition by means of applied X-ray Fluorescence Analysis requires the use of versatile methods of graduation. Presented in the paper modification of the method of theoretical coefficients enables to reach an exclusively high accuracy's of analysis on the base of comparatively simple graduation formulas.

In this paper a stabilization principle of two-frequency laser with a phase-anisotropic resonator, enabling to get an instability value of the laser frequency of 1.10^-10, is discussed. A phase-anisotropic mirror, having a reflecting covering layer with a corrugating surface, makes it possible to get an increased value of the differential frequency of 4 MHz at the radiation power of 0,5 mW.

Remote interferometer sensor principles based on additional phase modulation of lead-in fiber wave theoretically discussed and experimentally verified in various schemes: two-beam, mode- mode and polarization interferometers. Sensitivity to different physical parameters was measured.

Design is considered and basic characteristics of single-frequency stabilized He-Ne laser for linear measurements are resulted. It is shown, that use of a double contour of a thermal control with constant reference temperature of lock allows to create a compact design and to reach stability about approximately 10^-10 and reproducibility about approximately 10^-8.

The passive ring laser resonator of square size with a side equal to 3.1 m is created in Sternberg State Astronomical Institute for the determination of the Earth angular rate. This work deals with the construction of the resonator and mode-watching system, estimation of the resonator parameters, the influence of the temperature variations on the mode structure, the control of the resonator perimeter, the influence of the nonplanarity and the light polarization on the quality factor and, thus, on the accuracy of the Earth rotation measurements.

We present the results of investigations of the technique based on the principles of laser interferometry for measuring the thickness of two-layers films. The actuality of this kind of measurements is a result of necessity to control the geometric parameters of such films in scientific research and industry. The method of measurement is based on the analyses of the dependence of reflection coefficient as a function of the incidence angle of the laser beam due to the interference. To measure such dependencies we had designed experimental setups, described in our articles. This apparatus gives an ability to make the measurements of dependence of reflection coefficient as a function of the incidence angle in the range of angles from 30 degree(s) to 60 degree(s). The temporal duration of a single measurement is less than 0.2 ms, the diameter of probing spot is 30 micrometers and illuminance is less than 1 mW/mm². Fast measurement of angle dependence allows to get many data points that give an ability to determinate the parameters of two-layers films with high fidelity and precision. The possibility to determinate film's parameters follows from the analysis of the character of theoretical dependencies of the reflection coefficient R as a function of thicknesses of two layers with the different incidence angle of the laser beam (theta) . It can be seen that the reflection coefficients considerable depend on the layers thicknesses and the incidence angle. It gives an ability to design a technique to ascertain the simple correspondence among the dependence R equals f((theta) ) and the parameters of the film layers. An efficiency of this method was experimentally tested. We performed a series of measurements using the semiconductor structures Si₃N₄/SiO₂/Si having different thicknesses of the films Si₃N₄ and SiO₂, produced by the concern `Integral' (Minsk). The analysis of experimental and theoretical results shows that the described techniques can be applied for measuring the parameters of the multi-layers structures.

The influence of time of cracks existence on damage threshold of transparent dielectric is discussed. The influence of one macrocrack on damage threshold is evaluated. The probability of laser-induced crack growth is established.

Optical methods which provide the possibility of non-destructive control of structure changes arising from ion-photonic technological processing find of wide application for investigation of silicon and AIIIBV semiconductor compounds being of major importance in micro- and optoelectronics. IR spectroscopy of implanted, diffusive and epitaxial layers gives a rich information about the composition and impurity distribution. The influence of diffusion parameters on reconstructed impurity distribution profiles and p-n-junction depth are investigated. The role of the lattice absorption in GaAs determined by the interaction of IR radiation with optical phonons is shown for reflection and transmission spectra. For a more accurate fitting of the calculated and experimental dispersion dependencies it is necessary to take into account the concentration dependencies of the effective mass m^* and the relaxation time (tau) of charge carriers. In this paper results of the computer simulation of IR spectra in the wide range of m^* and (tau) variations for GaAs are presented also. It was drawn a conclusion about physical permissible values of m^* and (tau) from the viewpoint of applicability of the IR diagnostics of semiconductor structures.

A new technique for imaging an inner structure of x-ray transparent materials and biomedical objects characterized by small density changes of their structure components is presented. The phase imaging is based on two principal phenomena-radiation refraction in a tested object and diffraction in highly perfect crystals used both for creation of an incident beam and for imaging. It is shown that a phase radiography providing possibilities of an opacification free investigation of biomedical objects soft tissues can be developed upon the technique reported here.

The contribution deals with studies on residual stresses and microhardness of laser hardened carbon steel surfaces. Laser hardening can greatly improve the wear and fatigue properties by inducing a hardened and compressed surface layer. Residual stress distribution across the hardened tracks were measured by means of x-ray diffraction. It has been found that compressive stresses exist in the hardened zone of all the specimens studied. The microhardness increased by as much as 350%.

Residual stresses evolution in plastic deformation process of aluminum alloy and 18.8 steel was studied by the x-ray method. The measurements were carried out on two structural levels. The tensor character of macrostresses and RMS (root-mean-square) microstrains was demonstrated experimentally. On this basis a mathematical model of the process is proposed. The model proposed was used for the study of the residual stress evolution in the shape memory alloys.

This report presents the results of theoretical study, performed in the atomic theory group in St. Petersburg State Technical University for last years, on electronic structure of small metallic clusters and their interactions with external fields.

Universal short-time behavior of the critical dynamics has been confirmed numerically for some simple statistical models. The critical initial increase of the magnetization has been observed and the new dynamic exponent (theta) has been measured. We report further about a new kind of measurement of all the static exponents and the dynamic exponent z from short- time dynamics.

An analytical expression for short-range pair potential in polyvalent metals has been derived in the framework of the pseudopotential model. The similarity between new expression and well- known Morse functions is emphasized. Moreover, it is shown that within actual region of inter-atom distances in metal these expressions are interchangeable. A validity of the nearest- neighbor approximation, i.e. prevalence of short-range interaction in the cohesion, was found to be a sufficient base for calculation of compression dependences of the Gruneisen parameters for certain polyvalent metals. Besides this, by the use of experimental data, reasonable values for the pseudopotential model parameters have been obtained.

Contrary to the well-known method of rigid potential, based on superposition of atomic potentials, we suggest the method of a compliant (deformation) potential accounting for the elastic properties of distributed ion and electron charges. The elasticity of electron and ion media leads to the discontinuities in the electron-phonon spectrum at the boundaries of the Brillouin zones. For polar dielectric it causes to the discontinuities at the boundaries of the first Brillouin zone and to the total or partial suppression of electron-phonon scattering in this zone. For all crystals because of thermal `broadening' of the crystal planes it causes to the discontinuities at the boundaries of all Brillouin zones and to the partial suppression of electron-phonon scattering in the higher zones.

The method of a compliant (deformation) potential accounting the elastic properties of distributed ion and electron charges leads to the discontinuities in the electron-phonon spectrum at the boundaries of the Brillouin zones and to the suppression of electron-phonon scattering in senior zones. Both kinematical and dynamical electron diffraction theories is used to prepare counting procedure in the framework of this method. Presented results of the computer simulation by this procedure describes well some unexplained anomalous effects on experimental patterns.

Hydrodynamic equations including the effect of the quantum potential were analyzed and applied for the investigation of ballistic electron transport in inhomogeneous semiconductors. Spatial resonances and structures, optical oscillations of ballistic electrons are discussed.

Electron emission and luminescence associated with plastic deformation of ionic crystals have been studied. These phenomena are attributed to crossing of dislocations. Dislocation intersections are shown to result in color center generation; recombination of the centers gives rise to the deformation-induced electron emission and luminescence.

Some methods of electron, ion and photoelectron spectroscopy deal with very weak, strictly oriented beams of charged particles. Because of low beams intensity, these methods are substantially non-destructive, but on the other hand, the beam weakness limits severely their sensitivity and rapidity of spectra registration. Electron-optical characteristics of electrostatic potential (Phi) equals arctg(y/x) are considered. Compared to `traditional' fields used in energy analysis and monochromatization of electron beams, the potential (Phi) possesses some extra compressing feature. This gives additional possibility to enhance the entrance flows to be analyzed or monochromized, and as a result can allow to improve sensitivity and rapidity of some modern electron and ion spectroscopic methods.

We derive the equations describing the dynamics of an ensemble of atoms with (Lambda) - scheme of levels driven by two coherent resonant fields in a case when cooperative relaxation prevails over usual incoherent spontaneous emission. We investigate numerically temporal dynamics of mean values of the collective atomic operators. When the two-photon resonance condition is fulfilled then all atoms tend to be trapped in a coherent dark state, so coherent population trapping arises in a case of cooperative decay. Most important values characterizing this phenomenon such as the width of the black line and the time of initial transient stage of evolution are evaluated.

We present a theory of a new method for flame and combustion diagnostics. It is based on degenerate four wave mixing induced by pico- or femtosecond laser pulses. High reproducibility, substantially coherent nature of interaction, and possibility of simultaneous measurements on a short timescale in wide spectral range are the main advantages of the proposed method, which can be applied for investigation of rapid kinetic processes in dense and hot gaseous media.

Relations have been derived, that link the amplitudes of the experimentally observed magnetic resonance signals for various Zeeman sublevels of the H and D atoms with the electronic and nuclear polarizations of these atoms. Experimental data on the optical polarization of the H atoms in a helium-hydrogen mixture at T equals 300 K allowed one to determine the polarization degree of hydrogen spins, both electron and nuclear, which was found to be as high as (5 +/- 1)%.

The processes of the muonium and antimuonium creation on electron and positron intersecting storage rings are considered. The total cross section and the differential cross section via the muon-muonium invariant mass are calculated. The estimates of the modern accelerator possibility are made at LEP-2, FNAL (Tevatron-DIS) and HERA. The possibility of CPT invariance examination due to time life of muonium and antimuonium measurement is declared.

We present the first findings of the quantized conductance, EPR-EDEPR and NMR techniques which reveal the spin-dependent confinement and quantization phenomena in the silicon quantum wires created by the electrostatic ordering of the self-assembly dipole boron (B⁺-B^-) centers. These C_3v symmetry dipole impurity centers are regularly arranged along the edges of self-assembly longitudinal and lateral quantum wells (LQW and LaQW) which are naturally formed in the p⁺-diffusion profile inside ultra-shallow silicon n⁺-p⁺-p and n⁺-p⁺-n structures. A negative magnetoresistance that is evidence of the spin-dependent weak localization in self- assembly quantum wells at low electric fields is studied. The presence of natural quantum-size contacts inside self-assembly quantum wells is exhibited using the quantized conductance technique in weak magnetic fields.

The rheological model of new generation, generalizing numerous variants of the multisurfaces theories of plastic flow, is offered to consideration. By virtue of the unique mechanism of cross-links (or, in other words, interaction of plastic yield surfaces) and taking into account reasons of the thermodynamic correctness, it appears possible, within framework of simple (from the point of view mathematics) equations to describe thin qualitative behavior effects of material with shape memory. Even in the elementary case (which is discussed in this article) model allows to describe behavior of ferrous alloys, effects of pseudo-elasticity and the shape memory. The additional offers, permitting jumps in the theory parameters (mathematical analogue of phase transaction) allow more precisely to satisfy with experimental data. This model has shown acceptable results at cyclic deformation.

An approach is presented to describe the mechanical behavior of shape memory alloys undergoing a fcc-hcp phase transformation. Previously encouraging results have been obtained within the frames of the structure-analytical theory. They were achieved by introducing specific limitations on the maximum allowable size of martensite and austenite crystals. The model described in this report differs by the averaging procedure which is organized in a way to account for the symmetry of fcc and hcp lattices as well as the symmetry of the transformation strain tensor. The results of modelling have shown that symmetrical considerations can explain the transformation plasticity (strain accumulation due to a transformation in a stressed specimen) while direct or reverse transformations, the incompleteness of the strain recovery in the subsequent reverse or direct transformation and the asymmetry of the mechanical behavior for these two transformations. A qualitative agreement with experiments on Fe-Mn alloys (except for the scale of the asymmetry between direct and reverse transformations) has been achieved, the errors of modeling being probably connected with the dislocation plasticity not accounted for in the model.

The considerable amount of experimental facts showing step-by-step interchange of primary and secondary sliding during plastic deformation of metals is known. Analysis of numerical solutions of evolution equation for models allows to speak about a possible self-organization in dislocation subsystem for which quantitative description of the spatial dimension value D_f is proposed.

The kinetics of thermal breakdown of a dielectric is investigated by the computer simulation method using the 2D model of a dielectric with heterogeneous structure. The material is assumed to be placed in an external homogeneous electric field and is divided into the cells of different local electric field strength. The output, redistribution, and dissipation of heat from the cells are taken into consideration. It is supported that overheating of a cell leads to its destruction, and the breakdown takes place when two electrodes are joined together by a continuous chain of damaged cells. The correlation between the damage kinetics and the dependence of the average temperature of a dielectric on time is found. The equation connecting the breakdown time, material properties, and operating conditions is suggested.

Computer simulations of isolated unperturbed hydrocarbon molecules of C₁₈ with 1-5 methylene-interrupted cis double bonds have been carried out using Monte Carlo method based on the continuum model; the energy of nonbonded interactions, torsion and electrostatic terms have been taken into account. The molecule-fixed coordinate system (with the axes along principal axes of inertia of each molecule conformation) has been used. The orientation distribution functions (rho) (9) of C-H-bonds (9 is the angle between the bond and the axis), order parameters S relative to the maximum molecule span axis have been calculated. The widths of functions (rho) (9) (factor of bond `fluctuations') turned out to be dependent on the segment chemical structure and position, fluctuations increase from the center of the chain towards the terminals, all things being equal. The orientation distributions (rho) (9) of C-H bonds flanking the double bond are the most narrow, the functions (rho) (9) of CH₂- groups located between two double bonds are the most wide.

Molecular dynamics simulations of some lipid monolayers with unbranched polyene chains have been carried out. The simulation system consists of 24 lipid molecules arranged in a rectangular simulation cell, with periodic boundary conditions in the surface plane (X, Y directions). An sn-1-stearoyl (18:0) diacylglycerols that contained fatty acyl chains with (1) 22 carbon atoms and 6 double bonds cis in the sn-2 position-docosahexaenoyl (22:6(n-3) cis) and (2) 20 carbon atoms and 4 double bonds-cis n the sn-2-position-arachidonoyl (20:4(n-6) cis) have been studied at temperatures of 295 K. It has been shown that some important properties of bond ordering of hydrocarbon chains of lipid molecules in monolayer are similar to those of the isolated lipid molecules.

Molecular dynamics simulations of the lipids with unbranched polyene chains, (18:0)/(18:1(n- 9)cis), (18:0)/(18:2(n-6)cis), (18:0)/(18:3(n-3)cis), (18:0)/(20:4(n-6)cis), (18:0)/(22.6(n-3)cis), have been carried out. The potential energy function set used included the energy of nonbonded interactions, deformation of bond lengths (bond-stretching), valence angles (angle- bending), torsion angles, out-of-plane fluctuations of the double bonds and the carbonyl groups. All the hydrogens were treated explicitly. A polar head group was treated as an effective sphere with a Van der Waals interaction with the chain atoms. At temperatures about 300 K the mean number of conformational transitions per torsional angle in polyenoic acyls is higher than those for stearoyl. Some structural and dynamical properties of the molecules (the distribution of angle between `long' axes of the molecule two hydrocarbon tails) have been discussed.

In this contribution, we report on a study of the self-organization of comb-shaped polymer liquid crystal (PLC) chains into condensed globules and their disintegration using molecular dynamics method. We have found that a globule structure is formed in several stages: at first, a primary structure (stripe domains) comes into being as a result of sided chains attachment to the main chain, the second stage is associated with dimensional transformation of the stripe domains into 2D liquid-crystal-rich sandwich domains, during the third or aggregation stage a condensed globule forms from the domains, in the fourth stage this globule transforms to a loose globule which is disintegrated in the fifth stage, and during the sixth stage the disintegrated globule exhibits Brownian motion of its constituents. As in the case of longitudinal PLC chains, the self-organization stages of comb-shaped PLCs can be identified with the help of a temperature, pair correlation functions, and an anisotropy factor. By analogy with the longitudinal PLCs self-organization, it is found that two types of LC domains are formed during the self-organizations of comb-shaped PLC chains, namely, stripe and sandwich domains.

In this contribution, we report on a study of the compression of a crystalline polymer. This process is computer simulated by the method of molecular dynamics using the bead model. The initial crystalline structure is obtained by the self-organization procedure. The structure contains 500 beads and consists of two crystalline globules. Macroscopic characteristics like the stress-strain relation, temperature change during deformation, and mesoscopic characteristics like displacements, velocities, and paths of layer-averaged beads as well as microscopic changes are investigated. It is found that the stress-strain diagrams consist of three parts. The first part is due to elastic deformation, the second part is associated with laminar and turbulent flow of the layer-averaged beads, and the third one is related to periodic turbulent flow. These modes of motion correlate with the movement of polymer chain segments leading to the transformation of the initially perfect crystalline structure into a highly orientated one. On the basis of the observed structure changes, a constitutive equation is suggested. The equation describes work-hardening of polymer crystals under compression.

Load-induced submicroscopic defects of the surfaces metals were studied with a scanning tunnelling microscope. The methodological aspects of microscopy investigation of loaded metal samples in air and nitrogen were examined in detail. Defects shaped like in a print of a triangular prism are observed to form on the surface of polished and annealed samples of Cu, Au, Mo and Pd. Original defects were 5, 15, 22 and 18 nm deep on surfaces of Pd, Cu, Au and Mo and 50 - 100 nm wide and long. The vertex angles of prism were approximately equals 70⁰ in Pd, Au and Cu surfaces and approximately equals 50⁰ or approximately equals 90⁰ on Mo surfaces. Concentrations of the defects grows, reaches a maximum value and decreases. Then there are emerged new defects which depth is 2 - 3 times more than the original one. Their concentration grows, reaches a maximum value and decreases. The following type of defects of larger sizes create on the surface, their concentration grows, reaches a new maximum value and decreases, and so on. All defects have the form much like the original defects and their deep is a multiple the original defect deep.

By means of the molecular dynamics method using pair interaction potentials calculated within the framework of the pseudo-potential theory the rapid quenching process is simulated. The short-range order and atomic structure of Ni₈₀B₂₀, Ni₈₀Zr₂₀ and Zr₈₀Be₂₀ alloys in amorphous state are investigated. Total and partial radial atomic distribution functions, nearest interatomic distances and coordination numbers are determined. It is found that amorphization both in transition metal-metalloid and in metal-metal alloys occurs according to the unified formation mechanism of low-dimensional nanometric dendritelike aggregates. For each type of atoms the velocity distributions and spectra of vibrational states are received. The non-standard behavior of amorphous alloys is supposed to be connected with disturbing thermodynamic canonicity states, caused by the presence of nanocrystal heterogeneities of composition.

Molecular dynamics simulation is used to predict the structure factor of metallic alloys in the liquid state. Whereas the experiment does not easily and cheaply allow one to determine the partial structure factors, numerical simulation is able to get them provided the interaction potentials are known. The effective ion-ion forces are deduced from the electron-ion interaction. Then, the partial structure factors of Na-K, Na-Rb and Na-Cs are calculated, at equiatomic composition, and the influence of the size rate between the atoms of each component is studied.

Neutron irradiation of HTSCs creates a wide spectrum of defect sizes. In this work, the influence of small defects on the critical temperature and critical current density J_c is investigated. The characteristic behavior of T_c and J_c under this treatment is satisfactorily explained by a theoretical model considering the creation, migration and annihilation of small defects in the oxygen sublattice.

Using the sputtering version of the Monte-Carlo (MC) computer code TRIRS (TRansport of Ions and Recoils in Solid) we studied the collision sputtering processes under ion bombardment of a structureless target. Basically, the TRIRS calculation procedure is similar to the one used in the well known TRIM code. The important feature of the TRIRS with respect to other similar MC codes is the elaborate design of the particles trajectories, i.e., the scattering angle is calculated exactly using a scattering integral; the asymptotic trajectories of particles are computed taking into account a `time integral' for the specific interatomic potential used in calculation; during low energy events not only binary collisions, but also many-bode interaction may be taken into account. Comparing the calculation results and experimental data, we can see that TRIRS code is more realistic than TRIM in modeling the low-energy interatomic collisions, which dominate in sputtering processes. The special dynamic version of TRIRS code (DYTRIRS) was used to study the sputtering in the course of high-fluence irradiation when the target may be modified during irradiation. The high-fluence effects in preferential sputtering have also been discussed.

The (SiC)1(AlN) system is being extensively investigated due to the full miscibility of the two constituents, SiC and A1N, their good thermal and lattice matches, and the the possibility of modifying the band gap of the resulting structure over a wide range of 2.9 eV (6H-SiC) to 6.2 eV (2H-AIN) [1]. From a practical viewpoint, the solid solutions of SiC and A1N are promising materials for advanced high-temperature electronic and optoelectronic devices. One novel method of producing thin layers of(SiC)1(AlN) potentially suitable for microelectronic applications is the use of N and Al co-implantation into 6H-SiC at elevated temperatures followed by annealing, i.e. ion-beam synthesis. Hitherto, to the best of our knowledge, there has been only one report on the formation ofburied (SiC)1(AlN) layers in 6H-SiC by ion-beam synthesis [2]. This work is an attempt to model the fundamental processes that occur when 6H-SiC is implanted at elevated substrate temperatures with high doses of N and J ions to form thin buried layers of (SiC)1(AlN) having predetermined composition and dimensions. Results from the calculations have been correlated with those obtained by Rutherford backscattering/ channelling spectrometry (RBS/C).

We present parallel algorithms for molecular dynamics, which are suitable for a small number of processors. These parallel methods are based on a spatial decomposition of the simulation box, that takes advantage of a linked-cell list. The test of the algorithms is conducted, in the case of the Axilrod-Teller fluid at constant pressure, by evaluating the speed-up induced by the various communications schemes involved. These methods seem promising for studying complex physical properties, i.e. the dynamics of the glassy states and the structure at liquid- solid interface, which requires respectively long time scale simulations on small systems and large simulation boxes.

In this contribution, I report on a molecular-dynamics algorithm for the simulation of the self- organization of longitudinal polymer liquid crystals on the fully-distributed computer system. The peculiarities of the hardware and software for this system are discussed. It is shown that the parallelization of algorithm is carried out by the distribution of all the particles incorporated into a macromolecule among several processors connected to each other in the framework of selected virtual topology and by the parallel execution of several program copies by these processors. The timing of execution at the system of different processor numbers is discussed.

The approach describe in the paper unifies three main approaches to the development of hypermedia systems: language, screen and information based. The approach presumes providing a small set of conventional standard tools for this development and a wide range of tools for generating non-standard user's interface elements and control mechanisms for navigation. The concept and implementation details of development tools for these elements in HyperF system are considered.

This article presents a technique for computer control of a power boat movement in real-time marine trainers or arcade games. The author developed and successfully implemented a general technique allowing intellectual navigation of computer controlled moving objects that proved to be appropriate for real-time applications. This technique covers significant part of necessary behavioral tasks that appear in such titles. At the same time the technique forms a part of a more general system that involves control of less complicated characters of another nature. The system being an open one can be easily used by an action or arcade programming to improve the overall quality of characters artificial intelligence style.

In this article is presented an algorithmic approach to a problem of real-time visualization of foam arising in the stern part of the boat when it moves along the water surface. This problem usually appears during marine trainer's development. For solving of this problem a general method was developed. In this method two algorithms are used. The first algorithm generates procedural texture of foam using particle system as a model. The second algorithm uses this texture as an input data and renders it according to the boat movement parameters. This algorithm works 4 - 5 times faster than the first algorithm and could be used in real-time applications. The method presented in this article is a general method and it could be used for modeling fuzzy objects such as flame, clouds, etc.

This article presents some basic algorithmic solutions for some problems of texture mapping. All ideas that are discussed below were successfully implemented in an application, that allowed to produce interactive texture mapping and 3D texture painting. The market products that provide same capabilities are described. This tool was a part of system of 3D tools created for design and quality improvement of 3D models. The problems that are discussed herein refer algorithms of texture mapping. The most interesting is the geometrical correction of `seam' artifact of texture mapping for cylindrical and spherical mapping modes and `pole' artifact when using spherical mapping mode. Ebert and the others discussed the idea of the origin these artifacts, but he had not proposed solutions for those problems there. The method of geometrical correction that I suggest below may not be used in all cases because it changes geometrical description of a model. This is not always acceptable, but in some cases especially when the quality of model is more significant than model geometrical complexity, we can widely use method of geometrical abundance.

This article is dedicated to coordinate system binding problem. Such tasks appear during collection of geometrical information from different type of source data input system. The purpose of that binding is providing current transformation of geometrical objects coordinates during digitalization. This approach is used in geoinformation systems for first step information handle. It is a digitalization of source material. Article considers two approaches of this one: affine mapping and perspective mapping.

The investigation is devoted to the recognition of 3D object structure on the basis of the object pictures. Recognition problem is solved as statistical one, since the nature of the structures are stochastic most likely. In its turn the images are damaged with noise. Any structure under recognition is assumed to be a trajectory of a stochastic markovian process. A priori necessary information is the set of the values of the markovian process parameters to determine uniquely the general population of all structures for current recognition session. The significance level as input parameter serves to recognize certain domain of the general population the recognized structure matches with prescribed probability. Our method (algorithm and software) could gain wide-spread acceptance in object visual control, ecology monitoring, as well as to resolve the problem of some alive object growth description, i.e. plants and trees growth.

This article presents a mathematical model of forecasting of the stop-price on the securities auction, where an eminent places an issue among investors. The distribution function of the stop-price is the asymptotically normal function. It is proved with the help of two theorems that are represented in this article. Besides, it is represented formulas for the mean and the variance of the stop-price in two cases. The first case is when all auction participants are the same, and the second case, when auction participants are divided into two groups (large and small investors).

A new stochastic model of tumor growth is developed. The main goal of the investigation is to get some estimates of observable and unobservable parameters of tumor growth process under given assumptions of malignant cell behavior. The model allows to come over some difficulties encountered in reaching the above-mentioned goal by methods of stochastic branching processes theory, i.e. if the independence hypothesis is not valid. The principal phenomena of cellular level were taken into account to simulate cell population development: cell proliferation, reproduction, reproductive type of cell death and apoptosis. The model allows as well to simulate tumor treatment: radiotherapy and/or drug administration. The treatment is considered as a stochastic process of damage accumulation and reparation into malignant cell. This approach to biological phenomena modeling is extremely fruitful to test statistical hypothesis on the nature and mechanisms of tumor growth, in particular, on tumor growth latency.