Laser radiation has a wide application in molecules Raman lidar monitoring and concentration measurements in atmosphere for environmental and scientific purposes. Back scattering vibrational Raman lidar equation computer simulation for hydrogen and iodine molecules and its heavy isotopes with YAG-Nd, copper vapor and eximer 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 detectable molecules concentrations at ranging distances up to 6 km.

Atmospheric gaseous molecules Raman lidar monitoring has a wide application for environmental and scientific purposes due to its concentration measurements possibility. Back scattering vibrational Raman lidar equation computer simulation for hydrocarbons molecules with copper vapor lasers have been made to choose optimal lidar system for studied molecules monitoring in atmosphere at ranging distance up to 6 km. Background stray sunlight power were calculated to determine the minimal detectable molecules concentration level at these ranging distances.

The lidar complex of equipment based on TEA CO₂ laser specially designed for atmospheric sensing, with automatic tuning on generation lines in the spectral ranges 9 - 11.3 and 4.5 - 5.6 micrometers has been described. Besides regular transitions 00⁰1 - 10¹0 (02⁰0), the laser is able to generate powerful (megawatt) pulses on hot band (01¹ - 11¹0) lines. Considerable extension of the spectral range to the short-wave region is attained due to effective TEA CO₂ laser second harmonic generation in nonlinear crystals. Taking into the real potentialities of the lidar complex in hand, using a package of spectroscopic data HITRAN, computer simulation of atmospheric transmission has been made. On this bases, by the method of differential absorption a method has been elaborated for measuring small concentrations of a large number of gases, including especially dangerous atmospheric pollutants CO, C₂H₄, etc. This method was tried out on medium paths (approximately 1 km) in the real conditions of Minsk. Small (background) concentrations of a number of atmospheric gases have been measured.

The emission from laser produced plasma has been employed as a source of soft X-ray radiation for nanotechnology. By incorporating high Z elements into low Z solid hosts, targets have been fabricated which, when illuminated with high power Nd:YAG laser pulses, emit a significant proportion of the incident energy in a narrow wavelength region, with reduced continuum emission in the adjacent spectrum. Such a source would be of considerable utility in a projection lithography setup, where the presence of multilayer optics prevents the use of broadband soft X-ray sources. Cesium, barium and cerium were incorporated into different targets, resulting in different peak wavelengths for the emission. 4d - 4f transitions in highly ionized species have been identified as being responsible for the narrow emission feature. In addition, efforts to reduce particulate debris from the target are reported.

The being advantages ofthe laser gyro against the precise gyro with rotating mass are the cost efficiency and the theoretical rapidity for practical systems. There have been unavailable the relevant publications on the laser gyro's necessary precision providing and also on its rapidity and on the nonstationary systematic errors excluding in real time. on the other hand it is known that output frequency of continuous wave linear laser is establishing, even in stationary conditions, during the transition time of 20 minutes up to 3 hour for different laser types '. Thus most traditional measurements with continuous wave laser are used in stationary conditions, when the counting of output characteristics is begun after the necessary transition time is gone 2 Since the output ofring laser is proportional to the active media generation frequency, the laser gyro has the nonstationary systematic error with the same value of the transition time. The investigations have been performed would be derived in the two groups. There are the laser gyro error's "mathematical models" and so-called "dynamic compensation methods" discussed in . The "dynamic compensation methods" are based on using of the temperature-depending elements in feed back system of the output signal. The both methods require the lasting measurements of laser gyro output in the stationary conditions to define the coefficients of the error model or to determinate the characteristics ofthe temperature-depending elements. These measurements must be repeated or the parameters must be automatically tuned for any other case. So it is unreasonable. The plasma heat regime influence on the precise ring laser output is considered in this work following to The case of the heat influence on the plasma without the dimensions changing is supposed. The thin effects, as modes drag, mode competition and radiation trapping ,do not be considered in order to the more clear idea. The each component of laser active media (electron gas, ion gas, excited atoms, etc.) has its own optical properties and puts its deposit in the ring laser output instability The analysis resulted in shows that, in case of constant electron and ion concentrations and when the frequency of electron-ion collisions is comparatively low, one obtains the Fresnel drag effect with electro-neutral atoms only.

Some years ago we have built a dark-field microscope based on a catadioptric objective used as a dark-field condenser. The apparatus allowed to measure small (tens of nm) transverse displacements of light-scattering micro-objects, such as cell margins or intracellular particles. The principle of apparatus was the registration of the change in the intensity of light scattered from a moving structure that goes in or out the small scattering area (0.5 X 0.5 micrometers ). Recently, we have improved the method by equipping the microscope with a low power He-Ne laser. Highly coherent laser beam focused on the micro-object did not allow to form a real micro-image, but allowed to measure small displacements of the scattering structure via registration of the changes in the intensity of light scattered from the structure moving across the focused spot of laser light. Using the laser as a light source lead to an enhancement of the sensitivity of the apparatus, allowing the registration of displacements with amplitudes down to 1 - 2 nm.

reviously we reported the experimental observation [1] and theoretical simulation {2 of the drastic dependence of the state of polarisation of a neodymium laser passively Q-switched with a Cr4:YAG crystal (see Fig. 1 ,a) on relative orientations in the laser cavity of the passive switch (PS) and an partial polariser (PP). It has been shown that polarisation state of the laser is governed both by relative orientations of the Cr4:YAG PS and of the intracavity PP as well as by the energy density of a giant pulse (GP) in the switch. Complicate behavior of the polarisation state is due to an "interplay" between the PP action (which causes the linear anisotropy of the cavity) and that of the Cr4:YAG crystal (which causes the nonlinear anisotropy of the cavity). In particular, when the cavity parameters are chosen by a suitable manner, one should observe sharp. by 900,jumps ofthe GP polarisation azimuth, while only slight (1°) azimutal tuning ofthe Cr4:YAG crystal about the cavity axis takes place.

We are presenting a simple non-destructive method for characterizing SiC samples (Lely-crystals, CREE-substrates, and epitaxial films). With our method we observed ultraviolet differential reflection spectra of SiC samples and compared with pure Lely-crystal to estimate their structural quality. Our optical differential method is based on the experimental fact that doping of a crystal leads to appreciable changes of the optical fundamental absorption spectrum, which we interpreted as a uniform broadening and a shift of differential spectra. The broadening of absorption peaks can be caused not only by doping, but also by any defects of the crystal lattice (neutral impurities, clusters, micro-pipes and others), that destroy its periodicity. The shifts of these peaks inform us about the free carrier concentration. The experiment has shown we can detect minimum free carriers concentration up to n_min equals (N_D-N_A) equals 6 (DOT) 10¹⁵ cm^-3. Besides we can detect minimal frequency of impacts with lattice defects as v_min equals 3 (DOT) 10¹² s^-1. Converting to charged centers concentration it equals (N_D + N_A) equals 5 (DOT) 10¹⁶ cm^-3. Considering the small depth of light probe (less than 0.1 micrometers ) and delicacy of thin films, our contactless method is mostly applicable for its testing.

Experience of a group of researchers from Saint Petersburg State Technical University is summarized in this review. This work has been aimed at the synthesis of new non- traditional electron-optical systems for electron spectroscopy and mass spectrometry. The basis for it is the idea of the reversed electron-optical problem which leads to new original field structures and design decisions. In this paper, the theory is shortly described of the new charged particle energy analyzers called `Tutankhamon', `Arch', `Quasicone' and some others. Their calculated characteristics, such as energy dispersion, angular focusing, timing, etc., are given together with the real parameters of the devices which were made and tested experimentally. The applicability is discussed of the presented decisions to different fields of charged particle spectroscopy. The prospects for developing described methods are discussed and analyzed.

Previously developed approach [1 is extended to systems of noninteracting quantum particles in an external magnetic field. Feynman type series for grand potential, number of particles, internal energy and magnetization are derived. Numerical calculations at constant N for harmonically trapped systems of fermions and bosons in presence of the homogeneous magnetic field are carried out with the aid of both Feynman-type series and series over single particle states. Particular attention is paid to low temperature behavior of fermionic systems.

In 1989 Janssen, Schaub and Schmittmann have shown that universality and scaling hold already in the early stage of the dynamical evolution of statistical systems, if the system, initially at a very high temperature, is suddenly quenched to the critical temperature and then released to the dynamic evolution according to model A. This allows for a measurement of all the static and dynamic critical exponents and even for the critical point already in the short-time regime, i.e., far from equilibrium. Since the correlation length is still small here, the simulations do not suffer from critical slowing down, a problem encountered in the usual measurements in equilibrium. The concept has been successfully applied to a variety of statistical systems. We will report about recent results for the fully frustrated XY model, where the short-time approach is particularly efficient, since the standard cluster algorithm does not apply because of the frustration.

In this contribution we present the results of many-body calculations on electron photodetachment from outer subshells of Sn^- negative ion. The main attention is paid to the resonance feature near 5s subshell threshold related to the quasi-bound `5s5p⁴(⁴P)' state.

The states of an autolocalized electron in the field of an arbitrary intense electromagnetic wave are analyzed. By using the Kramers-Henneberger unitary transformation, the rapidly oscillating perturbation is transposed to the argument of a potential function. It is shown that the depth of the potential-energy well in which the electron is localized decreases monotonically with an increase in the strength of the external field. The analytic technique of a shifted 1/N expansion was used to express the position of the ground energy level as a function of the external-source intensity. The critical value of a parameter characterizing the external source is found for which the ground bound quasi-discrete electron energy level varnishes. The localized-to-delocalized-state transition is identified as a nonmetal-metal phase transition.

The production of neutral vector mesons (rho) ⁰, (omega) ⁰, p⁰ in hadron-hadron collisions is considered as a method of the proof of quark existence in virtual state and the quark fractional charge examinations. The estimates of considered process cross sections are given. The separation from other hadron processes is discussed.

We present the findings of the quantized conductance in a modulated quantum wire. The energy dependence of the transmission coefficient through a smooth and modulated quantum wire is analyzed to define the role of elastic back scattering process in the formation of the conductance oscillations and the current staircase. We demonstrate the oscillations of 1D conductance plateaus as a function of drain-source voltage that are evidence of the interference effects caused by varying the energy of ballistic holes in the modulated quantum wire electrostatically created inside the silicon self-assembled quantum well. The Aharonov-Bohm (AB) rings prepared inside the silicon self-assembled quantum wells are used to study the interference of ballistic carriers tunneling through parallel quantum wires as a function of their length and modulation which are revealed by varying the external magnetic field and the drain-source voltage. The AB double-path interferometer defined by the quantum point contacts from the leads is found to exhibit the periodic oscillations in the quantized conductance that are evidence of the magnitude and phase of the transmission coefficient through the quantum wire embedded within the AB ring's arm.

We present the first findings of high efficient Er³⁺- related electroluminescence ⁴I_13/2 yields ⁴I_13/2 from self-assembled silicon nanostructures with sizes varying from 1.0 to 10 nm that are naturally prepared as a subsequence of quantum-size n^--p junctions. The built-in electric field induced by these n⁺-p junctions is found to result in the Stark effect that perturbs strong sp-f mixing due to the electron-hole localization on the Er³⁺-ions incorporated into nanostructures. This spatial confinement is shown to cause ultrafast energy transfer to the erbium-related centers which increases with decreasing size of nanostructures thereby enhancing the electroluminescent efficiency.

We present the findings of single-electron transport through the Ag-related center as a quantum dot weakly coupled by tunneling junctions with the silicon quantum wire which is formed at the Si (100) surface by the crystallographically- oriented chain of the adsorbed silver atoms. The quantum dot of this art is shown to be variable thereby demonstrating the quantum staircase in forward bias and to change a position as a function of charge states revealed by the Coulomb single-electron charging in reverse bias. The effects observed seem to be due to a field-dependent asymmetry of the barriers isolating the Ar-related center from the silicon quantum wire.

The possibility to determine simultaneously a wide range of the characteristics of solid surfaces is of great importance in studying their electronic properties. In material science, surface physics and emission electronics it is particularly interesting to get at the same time information about elemental composition, chemical state and work function distribution ofthe surface under investigation. Up to a present, these surface parameters have been determined separately, under nonidentical conditions. The composition and chemical state ofthe surface are usually studied by different kinds of electron spectroscopy most often -by Auger electron spectroscopy (AES); the absolute value ofwork function and its relative distribution along the surface are measured by the raster electron-beam method 2 Both methods allow to determine the local surface parameters mentioned above with practically the same spatial resolution ( -100 im2).

Molecular dynamics simulations of six monolayers composed of the molecules 2,3-diacyl-D-glycerolipids that contained stearoyl in the position 3 and stearoyl, oleoyl, linoleoyl, linolenoyl, arachidonoyl or docosahexaenoyl in the position 2 have been carried out; 1.5 nanosecond simulations were performed at T equals 303 K for the monolayers of unsaturated molecules and at T equals 326 K for saturated one. The average areas per lipid molecule over the simulations were 65.6 angstroms² in 18:0/18:0-monolayer, 66.2 angstroms² in 18:0/18:1(omega) 9cis-monolayer, 66.1 angstroms² in 18:0/18:2(omega) 6cis-, 67.4 angstroms² in 18:0/18:3(omega) 3cis-, 70.6 angstroms² in 18:0/20:4(omega) 6cis- and 71.4 angstroms² in 18:0/22:6(omega) 3cis-monolayer. The C-H bond orientation distributions and C-H bond order parameters profiles about the monolayer normals have been calculated. The bond orientation distribution function widths turned out to be depended on both the segment location in the chain and the segment chemical structure. The computer simulation data indicated the widths of the distributions of CH₂-groups located between the double bonds of polyunsaturated chains to be much greater than that of C-H bonds of double bond carbons (broadening effect).

The method of molecular dynamics is used to study the formation and self-organization of different configurations of double helics. Calculations are performed in the frames of so called beads-on-a-string model with the help of a set of long-range anharmonic pair potentials obtained in the previous investigations. It is found that two different types of double helices, which consist of intertwined or inserted into each other helical chains, are formed from initially straight bead chains. The type of helix formed depends on the competition of weak interactions along the single chains and between them. In the case of rather long double helices, both types can undergo `shape' transformation.

In this contribution we report on a method of incorporating electronic degrees of freedom into interatomic interactions. The method leads to new temperature dependent potentials which are obtained on the basis of synthesis of quantum and statistical mechanics. The method allows to model temperature dependent processes such as phase transitions, deformation at different temperature, self-organization.

In this contribution we report on a study of a common cellular regulatory unit with positive feedback loop: self activating gene. The system was described by the chemical kinetics theory, that provides a set of ordinary differential equations. Analysis of them allow us to consider the self activating gene as a nonlinear convergent oscillator with the potential function in the form of a third degree polynomial. The model developed is convenient for applications in description and analysis of a wide range of biological processes.

With increasing IC packing density IC manufacturing processes are becoming more and more complex and tolerances of process parameters more critical for production yield and product reliability, and thus the economic viability of the IC manufacturing. At the same time IC structures can no longer be treated as 1D or even 2D. Therefore statistical multi-dimensional simulation of IC technology accounting for fluctuations of process parameters becomes more and more important. We present preliminary results of the statistical performance of the response surface methodology applied to numerical process and device simulation for the evaluation of the influence of random process fluctuations on the device performance.

Molecular dynamics calculations are performed, by using a parallel algorithm, to study the supercooled liquid and the liquid-glass transition of xenon. To investigate the competitive role of the three-body interactions, we present and discuss our results for the pair correlation function, the specific heat at constant volume, as well as the mean- square displacement and the velocity autocorrelation function. The three-body contribution, which is found to give properties that predict very closely the available experimental results, plays an important role in describing the physical properties in supercooled and amorphous states and is found to have the effect of increasing the glass transition temperature.

Both the static and dynamic properties of liquid caesium are investigated for a thermodynamic state near the melting point. The effective pair potential is calculated with the Fiolhais et al. pseudopotential initially developed for the solid state. The static structure factor is determined within the hybridized mean-spherical approximation and the dynamic structure factor owing to the viscoelastic approximation. The results obtained are in good agreement with the experimental measurements reinforcing the ability of this pseudopotential to be transferable from the solid state to the liquid state.

The method of molecular dynamics is used to compute the binding energies of different configurations of vacancy clusters in (alpha) -iron. Calculations are performed with the help of long-range oscillating pair potentials found on the basis of a model pseudopotential approach. For improving the convergence of the lattice sums, a space window is introduced. It is found that in the range from divacancy to 27-vacancy various atomic configurations are formed which can be considered as nuclei of dislocation loops, voids, and new-type crystal lattices. Nickel addition to (alpha) -iron leads to increase in the binding energy of mobile vacancy clusters. The increase is accompanied by dimensional transition with the resulting formation of immobile clusters.

Different configurations of self-interstitial atoms (SIA) in (alpha) -iron and their interaction with the voids have been studied by molecular dynamics method. Pairwise interatomic potential was calculated on the basis of pseudopotential theory. According to the results obtained, the most energetically preferable configurations of the SIA are <111> dumb-bell and crowdion. Migration energies of these stable configurations along their axis are very small and do not exceed 0.01 eV. It was shown that under the stress field of the void nucleus, containing 9 vacancies, crowdion may athermally migrate and, as a result, be captured by the void nucleus from considerably large distance. The form of the trajectory for crowdion athermal motion depends on the orientation between radius vector of the crowdion center and its axis. In dependence on the crowdion axis orientations in relation to the void nucleus, 2- or 3-D athermal motion of an interstitial takes place. Modeling of crowdion interaction with a large void additionally has shown that the interaction between the crowdion and elastic field of the void can cause its athermal motion, which resulted in the crowdion capture by the void. The distance of such a `pulling' of a crowdion into a void can reach several diameters of the void.

The nucleation of interstitial dislocation loops in (alpha) - iron under irradiation has been studied a the molecular dynamics method. Pair interatomic potential was calculated on the basis of the pseudopotential theory using the Animalu form-factors and the dielectric function of Vashista and Singvi. In order to decrease a computational error associated with the cut off of the potential, a special procedure was applied. On basis of the results obtained, the microscopic mechanisms of formation of different interstitial loops are proposed. The results of the modeling are in a good qualitative agreement with experimental data.

Physical and chemical properties of ultrathin suicide films are of considerable interest because of their reduced coordination and symmetry lead to important changes in crystallographic and electronic structure with respect to the same material in the bulk. These suicides are characterized by a very low Schottky barrier to n-type Si combined with a small electrical resistivity and are therefore, attractive for Si based technology '.Since interface with Si is buried by an overlayer and its structure depends on the materials and conditions during formation, it is difficult to clarify atomic structure of the interface. Hence, it is important to know the atom arrangement at the metal-silicon region in order to clarify the electronic structure of real interfaces. The formation of silicide films on silicon is accompanied by atom adsorption on surface, metal atom diffusion into silicon lattice, forming and diffusion of point defects which are taken into account in all above mechanisms. For example, the formation of Pd2Si on silicon generates point defects, which diffuse into silicon substrate and promote the diffusion of buried dopant layers. Peculiarity of this process is characterized by asymmetric diffusion of buried marker layers and surprisingly low diffusion process temperature (near 200°C). Buried marker layers move toward the silicon surface. This anomaly is explained as the result of silicidation process. The similar diffusion phenomena (asymmetric diffusion of buried Sb-doped p-n-p-junctions) occured during Co and Ti silicide formation. These low-scale effects may be adequately investigated by means of molecular dynamics (MD) method. Here we present some of preliminary results of low-energy silicide formation technology simulation carried out by this method

The problem of building 3D models of various types of topological surfaces aimed at their visualization is considered. Up-to-date 3D graphics language (Open GL, VRML, Java3D, etc.) allow users to represent any spatial surface as a polygon mesh approximating the surface. A general approach to generating the mesh is described, where coordinate values of the polygon vertices are calculated with a regular algorithm. Most topological surfaces have peculiar points where a special algorithm has to be applied. The following problems are discussed in the paper: what types of the peculiar points exist; how many of them are on surfaces of various type; how to reduce their number and how to change the regular algorithm in their neighborhood. The paper is illustrated with screen images of typical models such as sphere, torus, hyperboloids, Klein's bottle, etc.

Intuitive interaction with computer systems can be enhanced by letting the user manipulate physical objects. In this paper we describe a novel input system, allowing the user to specify translations and rotations by manipulating cardboard shapes. A camera records the shapes' configuration. Some optimized image recognition algorithms, based on the Hough transform, are used to collect positional and orientational data concerning the cardboard shapes. This information is translated to manipulations on virtual objects in the application.

One of the most difficult problems in the marine trainer development is visualization of the moving boat. This problem consists of two separate subtasks: • development of the realistic physical model of a moving boat • modeling of various phenomena accompanying boat movement such as water foam arising in the stern part of the boat The significance of the realistic physical model of the boat movement is intuitively clear while the importance of the second problem requires some explanation. The boat movements along water surface looks quite unnaturally without water foam even though it is based on the exact physical model. Therefore the problem of visualization of water effects accompanying boat movement is as important as boat movement modeling itself. The article presents an algorithmic approach to a problem of visualization of water foam arising in the stern part of a boat. The foam is not a conventional object for 3D graphics technology. As most other natural phenomena such as fire smoke, etc. it could be hardly represented with a bounding surface, as it is usual for solid shapes. The frame rate in marine trainers should be greater then 20 frames per second so strong time restrictions should be applied to the visualization algorithms. Due to this restrictions it is impossible to use a straightforward physical processes modeling. Instead the new approaches are needed aimed on visual similarity rather then physical accuracy.

This article is dedicated to the research of geometry level of detail technology for systems of real-time 3D visualization. The article includes the conditions of applicability of the method, overview of existing approaches, their drawbacks and advantages. New technology guidelines are suggested as an alternative to existing methods.

Virtual reality systems gained a wide expansion nowadays. They appear as three-dimensional trainers and simulators, video games, various visualization systems, virtual www-spaces and so on. The area of applications for such systems is rapidly expanding, which is supported, in the first row, by a quick development of appropriate hardware and software tools. The main task in virtual reality systems is allowing a user to effectively be present in the space, navigate through it and also to interact with the space, objects and characters (intelligent agents) embedded in the created synthetic space. One of the tasks raising on building virtual reality system is a creation of behavioral animation (or simply behaviour) of intellectual agents. The behaviour represents actions that are usually described with terms of natural speech, having social, psychological or physiological meanings, and that are not necessarily trivial in reducing to actual animation, i.e. movement of effectors, skeleton etc. [1]

There were analyzed some approaches to user interface design. Most existing interfaces seem to be difficult for understanding and studying for newcomers. There were defined some ways for designing interfaces based on psychology of computer image perception and experience got while working with artists and designers without special technique education. Some applications with standard Windows interfaces, based on these results, were developed. Windows environment was chosen because they are very popular now. This increased quality and speed of users' job and reduced quantity of troubles and mistakes. Now high-qualified employers do not spend their working time for explanation and help.

A distributed computing system with time-critical applications is studied in this paper. The stochastic model was suggested to estimate the level of QoS even in the presence of faults. This paper examines the behavior of schedules in stochastic environment characterized by random processor failures that may delay execution of tasks and cause the actual situation to deviate from a specified schedule. The author intend to understand the behavior of schedules under uncertainty and to formulate scheduling problem into a convex program.

In the article the normalization of samples, distributed under continuous low is described. The direct and inverse transformation shown for the cases when the distribution function of a sample is known and unknown. The mismatch of this transformation for second case is discussed too.

The gas-turbine powers and power plants (GTP) are widely used in diversified industries, such as the power engineering, aircraft and transport. In previous years the main direction of their development was increasing the parameters of a thermodynamic cycle: gas temperature in front of a turbine and pressure ratio. However, in the last few years the possibility of increasing the gas-turbine plant efficiency at the expense of such parameters growth has diminished considerably because the thermodynamic cycle parameters came nearly to their theoretical limit. Most clearly it can be seen on an air gas-turbine engines example, in which the gas temperature level in front of the turbine has reached 1800 C. In these conditions, the main development trend for GTP is to increase the units efficiency in all operational modes. One way out is the complex nonconventional scheme GTP designing. in which there are additional units and channels switching the flow of a propulsive mass in different operational modes. The gas-turbine engines which have a high performance at small subsonic, and at large supersonic flying speeds are developed in aviation. Such GTP is called a variable-cycle engines (VCE). Among them, there are not only electric generator driving GTP, but also steam heating GTP for building heating system, and compressed air generators. Since the load distribution in all these directions can change during the work, such power GTP need to have a rather complicated scheme. As an example, let us consider the project of a variable-cycle engine for a perspective supersonic airplane, a VCE with a common fan turbine. When designing such gas-turbine engines, the significant problem is the compatibility of all the units power characteristics at large quantity of structurally geometrical limitations on them. The units must have not only high efficiency values, but also to be matched with each other on power parameters: power, consumption of a propulsive mass, rotational speeds, and also on design and geometrical parameters -diameters, number of stages etc. For this purpose, the program complex of a computer-assisted design of complex scheme GTP is developed, EACAD. These programs for modeling different engines with the purpose to ensure the compatability of all the units parameters in the most of Designer Bureaues are made anew for each particular scheme or for the several similar schemes. The EACAD developers have given large attention to the possibility to design and to calculate the schemes of gas-turbine engines without any limitations on their structure. EACAD allows to make the GTP scheme, to determine the main GTP parameters (thrust, power, specific ftiel consumption etc.), and also to determine the main geometrical sizes (provisional length, area of cross sections). The engine scheme is injected into a printer.

Thermal wave measurements on 6H-SiC with a particular emphasis on Al⁺ and Al⁺/N⁺ implanted 6H-SiC was carried out. The 6H-SiC wafers were implanted at different substrate temperatures. The photothermal measurements of the conversion coefficient K and the reflectivity R show a strong dependence on the implantation temperature. This result is discussed in relation to Rutherford backscattering spectrometry/ion channeling measurements. The behavior of the reflectivity in dependence on the implantation conditions could be modelized by using a simple two layer optical model. The carried out investigations of the implanted SiC demonstrate, that photothermal methods are suitable for both research and on- line production use.

The element sensitivity factors method and the factor analysis are the most important methods for quantification of Auger depth profiles. The present paper puts forward a criterion for the decision in which cases the use of factor analysis is necessary for the quantification. The presented criterion uses the fact, that changed chemical bonds via sample depth are connected with changed element sensitivity factors. A chosen SiC-Si sample was investigated by Target Factor Analysis. The influence of data pretreatment like data selection, normalization and filtering are discussed.

The process of copper nanoclusters evolution in amorphous films, formed by co-sputtering of Cu and SiO₂, has been investigated theoretically. Bulk copper diffusion during sample annealing after fabrication have been described by kinetic equation set and cluster size distribution function have been obtained. The reasonable agreement of theoretical and experimental results has been achieved. The values of bulk copper activation migration energy have been estimated. For investigating clusters formation with different copper content method of molecular dynamics have been developed. Both methods have reasonable agreement for low time diffusion.

Monte Carlo study of the transport of non-relativistic electrons in the matter is presented. The simulations were made using a new computer code TRELM (Transport of Electrons in Matter) which is recently developed by authors. This code is based on individual scattering technique which make allows one to trace each electron history taking into account both elastic scattering and electronic energy losses. The main objectives of this work are to calculate imparted energy distributions in the target and related parameters at low-energy electron beams irradiation as well as to investigate formation of the heavy ion track due to secondary delta-rays transport processes. It is found that calculated data are in reasonable agreement both with previous similar results and with recently obtained new experimental data on observations of heavy ions tracks shapes in nuclear photoemulsion near ion stop-point.

The fundamental processes that occur when SiC is implanted at elevated substrate temperatures with high doses of N⁺ and Al⁺ ions to synthesize buried layers of (SiC)_x(AlN)_1-x have been investigated. The influence of the mechanical stress induced by formed clusters of interstitials has been taken into account by adding a special term to the expression of current density of defects in the set of differential equations. The satisfactory agreement of simulation results and experimental data is obtained. The theoretical treatment has enabled one to determine the role of internal stress field on the evolution of defect distribution.

The analysis of the effect of initial semi-insulating gallium arsenide quality on microwave ion-implanted metal- semiconductor field-effect transistors (MESFETs) parameters has been carried out. The leakage current method, `photofield-effect transistor with bias on substrate' technique for MESFET structures on GaAs wafers, Hall measurements, optical absorption, photoluminescence, ellipsometry have been used for evaluating semi-insulating gallium arsenide quality. The criteria for sorting initial semi-insulating gallium arsenide as material applicable to direct ion implantation in the process of microwave MESFETs and integrated circuits fabrication have been developed. The possibilities of prognosticating MESFET parameters and their thermal stability are defined by the compensation scheme taking into consideration the presence of deep impurity levels, deep level concentration and peculiarities of their distribution along ingot length and along wafer diameter as well as deep level redistribution during annealing.

In recent years, microstructure engineering has gamed significant attention, with the goal being to develop predictive tools which quantitatively link the operational parameters of an industrial process to the properties of the product it makes. Recent emphasis has been on developing microstructure models for hot strip rolling of advanced low and ultra low carbon steels [1 -3]. To improve mechanical properties of these steels, cooling paths have to be designed which optimize the ferrite microstructure resulting from the austenite decomposition. Accelerated cooling on the mn-out table of a hot strip mill has become an accepted tool to refme ferrite grain size by lowering the austenite-to-ferrite transfonnation temperature. Although phase transformations in steels have been investigated more extensively than those in any other material, there is still a considerable need to gain insight into the nucleation and growth mechanisms of ferrite under industrial cooling conditions. The present paper summarizes approaches to model the transformation kinetics utilizing nucleation and growth theories for ferrite.

Synthesis of Cordierite was carried out by solid state reaction sintering of oxides and Andean mineral precursors. Strong mechanic mixing was employed, with and without bismuth oxide added as a flux. Powder x-ray diffraction patterns were taken after sintering at different temperatures, in the range from 900 degree(s)C to 1400 degree(s)C. A comparative analysis was performed to investigate the phase formation dynamics for compositions with bismuth contents of 0, 5 and 13 %wt Bi₂O₃. Hexagonal (alpha) -Cordierite was obtained after sintering at 930 degree(s)C under the appropriate conditions. The behavior of the distortion index (Delta) with the sintering temperature reveals how the cordierite order-disorder polymorphism is affected by the bismuth addition. The resultant structure became more ordered with increasing sintering temperature. From the distortion index behavior and DTA measurements it can be observed that all the thermal events are shifted to lower temperatures for increasing bismuth contents. A preliminary study on sintering kinetics is presented from dilatometric measurements. The addition of bismuth would act as a catalyzer, through a liquid phase sintering process, by increasing the reaction rate and lowering the diffusion barriers.

Small-angle x-ray scattering and electron Auger spectroscopy were used to study the distribution of the excess free volume and the chemical composition of the surface layers of amorphous alloy ribbons. The relationship between these structure parameters and the surface crystallization characteristics of amorphous alloys is analyzed.

The durability of materials realizing shape memory effect testifies that the accumulation of defects of a crystal structure in this process occurs more slowly in comparison with irreversible deformation. The attempts were undertaken to simulate process of generation of a field of stresses in process of martensite transformations, but they did not prove to be true by experimental data. In offered work the attempt of an experimental research of a residual field at a structural microlevel is undertaken. Meaning complex phase structure interfering to a choice of two orders reflection from family of planes or frequently even of two peaks from one phase, as a first approximation investigated root-mean-square (RMS) microstrains and coherent block sizes analyzing one diffraction peak. In case of necessity used also separation of the overlapped peaks of different phases.

Simultaneous measurements of electrical resistivity and unelastic strain accumulation in Ti - 49.5 at. %Ni undergoing two-step B2 yields R yields B19' martensitic transformation were performed. To exclude the influence of specimen size changes during the deformation all experiments were made in torsion. It was detected that noticeable part of strain recovery after heating under a stress and active deformation in martensitic state takes place before the start of the reverse transformation and obviously is connected with twinning. At the same time the two-way shape memory effects are caused by the martensitic transformation.

Diamond films deposited on various substrates were characterized nondestructively by Raman spectroscopy and X- ray diffraction (XRD) to evaluate their stress states and film quality. The X-ray diffraction method is further divided into two methods, i.e., the low incident beam angle X-ray diffraction, and Clemens-Bain method for the textured films. The whole-pattern-fitting structure refinement method, or called `Rietveld method' was adapted in XRD method to improve its accuracy. The film adhesion, film morphology and film structures including its non-diamond carbon content, crystal size, texture coefficient, film thickness and surface roughness were also examined. The correlations between structure and residual stress of the films on various substrates and under various deposition and pretreatment conditions were analyzed. The feasibility of nondestructive evaluation the film quality and stress states, and the origins of the residual stress of the films were discussed.19

Multilayer coatings of (Ti, Al) N_x, (Ti, C)N_x and (Nb, C)N_x with bilayer thickness of 0.8 - 8 nm have been deposited by reactive sputtering on stainless steel substrates. Vickers microhardness measurements in the load range of 3.10^-3 to 1 N were performed using a self- adjusting tester. It has been shown that in order to obtain the true hardness of multilayer coatings on a softer substrate, the indentation depth should not exceed about 10% of the coating thickness. Indentation criteria for polycrystalline, amorphous and nanostructured multilayer coatings are compared. The obtained criterion for multilayer coatings is close to that for amorphous films.

Evolution of the orientation distribution function inside individual grains has been examined by local X-ray technique. The material studied was aluminum polycrystal with a mean grain size about 0.5 mm. It was shown that existing theoretical models can not predict reorientation of the grains examined. This is due to the fact that a local grain neighborhood effects stronger than an initial grain orientation on grain rotation. The strong orientation spread occurs inside the grains. The observed regularities of the spread are interpreted in the terms of grains subdivision by dislocation boundaries.

A modification of the multisurface theory of plasticity with one active surface of equal plastic compliances was executed. While the modification a character of a loading path was taken into consideration. The constitutive equation give the possibility to make a prediction calculations when either loading or strain path (in whole strains) is known. Also the modification of structural model was executed. The predictions of theories were compared with test results (both authors' and known from publications) of two-parameter loading on steel and copper tubular specimens. The calculations using one surface theory of plasticity with kinematical hardening were also made. Last results were in worse agreement with experimental data than the other theories predictions.

Based on the rheological 1D model the properties of a generalized elastoplastic material are described in this paper. This model is used to analyze the behavior of cable- in-conduit superconductors under cyclic transversal loading. The modification of elastoplastic model is described by introducing the dependence of the elastoplastic properties on the magnitude of the stress. The constitutive equations are explicitly deduced. The parameters of the model are selected according to experimental data. The constructed theoretical diagram illustrates the potentialities of the model.

Starting from the basic equations of the 3D continuum a shell theory will be derived, considering geometrically and physically nonlinear effects, transverse shear strains and thickness stretching. Motion is described using a material description with convected coordinates. This means the independent variables are the material coordinates (theta) ⁱ of the material points P and the time t. Due to the specifics of this description the shape of the coordinate lines, the base vector system and the metric are dependent on space and time. In this case a rate formulation of the field equations proves to be useful, which leads to a nonlinear initial-boundary value problem. The nonlinearity is implied in the initial value problem whereas the boundary value problem is linear in terms of displacement rates.

The current paper presents finite element evaluations of brittle fracture parameters for subinterface and interface cracks in composite materials. It consists of two basic parts: in the first part the description of virtual crack closure integral methods is given and the finite element realization of this method is also presented. Second part of the work deals with the numerical analysis of different interfacial and non-interfacial cracks in heterogeneous media. The discussion of the obtained results is performed and the conclusions are drawn.

This paper presents new finite element (FE) approach to modeling edge effects in beam sandwich structures. Developed approach is based on the mixed 2D and beam FE models conjuncted by means of the penalty function method. Several tests of sandwich beams and frames bending with different boundary conditions and laminate types were solved in order to verify the accuracy of new FE methods, algorithms and software based on the mixed 2D & Beam FE models. The influence of penalty factor on the spectral condition number of stiffness matrix and on the residual norma of solution/constraint for the different isotropic and sandwich structures was investigated. The FE analysis of real sandwich beam joint is presented. Results of this analysis show the advantages of the developed approach.

In this work a fully coupled model for the dynamic analysis of partially saturated plastic soils including water and airflow is presented. The innovative contribution of this research mainly consists in the extension of the model to the dynamic analysis of porous media with two simultaneously flowing immiscible fluids. The model adopts the solid displacements and the pressures of fluids as primary unknowns from which all the other local quantities are derived. The governing equations are presented in form of partial differential equations, then the algebraic form is derived by finite element discretization in space and using the Newmark method for the time integration. The model has been validated with respect to documented experiments on partially saturated soil in quasi-static condition. Moreover applications of the numerical model in dynamic conditions have been developed and the results are commented and compared with experiments of various researchers where available.

A new combined approach to analyze a physiological state of the human shank is developed. Investigated vibration research complex records resonance curve of the shank tissues automatically for different kinds of vibration excitation and for various positions of the foot. A special computer model is implemented for the estimation of the experimental data, for a priori prognosis of the bio-object behavior and its dynamic characteristics in the case of various kinds and of different degrees of injury. The method is described by the viscous-elasticity non-homogeneous 1D continuum equation. It is solved by finite element method. The problem in shank cross-section is solved by boundary element method. The analysis of computer simulated resonance curves makes it possible to understand the experimental data correctly and to check the diagnostic criteria of the injury.