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The dynamics of changes in the surface morphology of recrystallized tungsten foil under the action of uniaxial tension was studied in situ by the methods of low-energy electron diffraction, electron Auger spectroscopy, atomic force microscopy, scanning electron microscopy, and energy dispersive scattering. It was established that, before the rupture of the sample, the multifractality–monofractality transition consists of several stages: the narrowing of the multifractal spectra of the singularities of the surface, the rotation of the structural blocks of the dominant (112) tungsten face, and the transition of the lattice of the dominant face into a diffractive-disordered state.

The features and generality of the effect of hydrostatic pressure and annealing on the surface relief of the contact and non-contact side of the Fe77Ni1Si9B13 metal glass ribbon are revealed. The relationship between transformation of the ribbon surface inhomogeneities under these effects and possible formation of nanocrystalline regions are analyzed. We found that the evolution of the surface inhomogeneities at the contact side of the ribbon after annealing procedure leads to appearing of discrete-sized fractions in these regions.

The effect of ultraviolet radiation and a strong electric field on the conductivity of structures based on two types of polymorphic gallium-oxide films is studied. Both types of Ga2O3 films are obtained by hydride vapor phase epitaxy on smooth and patterned sapphire substrates with the orientation (0001). In one and the same process, on smooth substrates, α-Ga2O3 films are obtained and, on patterned substrates, gallium-oxide films with regular structures perpendicular to the substrate containing alternating regions of α- and e-phases are deposited. Resistive structures based on two-phase films exhibit a transition from a state with low resistance to a state with high resistance under the action of radiation with λ = 254 nm and a strong electric field. The time of response to UV radiation is 5 s, and the recovery time is shorter than 1 s.

The effect of UV radiation and a strong electric field on the current–voltage characteristics of resistive structures based on polymorphic gallium oxide (Ga2O3) films is discussed. Ga2O3 films were deposited by the method of halide vapor phase epitaxy (HVPE) on smooth and patterned sapphire substrates with a baseline orientation (0001). α-Ga2O3 films grow on smooth substrates, and gallium oxide films containing α and e phases grow on patterned ones. A switching effect was detected in the metal/Ga2O3/metal structures based on two-phase films. When exposed to radiation with λ = 254 nm and a strong electric field, the structures pass from a low resistive state to a high resistive state.

Object and purpose of research. This paper discusses strength parameters of Project PV300VD mixed-navigation passenger vessel in order to describe feasibility assessment procedure for large ships with considerable bow overhang. Materials and methods. Following common methods of ship theory and design, as well as of naval structural mechanics, this study relies on Marine Engineering Bureau and LOTOS shipyard databases and on the rules of various classification societies.

Crystallization of NiTi ribbon metallic glass of equiatomic composition has been studied by x-ray structural analysis and atomic force microscopy. The surface of the original ribbon obtained by spinning contained only crystallites of impurity phases. As a result of exposure to annealing for 10 min at a temperature of 500°C, a phase transition has been observed in the form of Ni50Ti50 phase ordering. The parameters of inhomogeneities, roughness, fractal dimension, and values of multifractal formalism have been calculated in the analysis of the ribbon surface geometry. It has been found that all the above characteristics had local extremes after heat treatment at 500°C for 10 min. In particular, the minimum of the values of the widths of the spectra of singularities has been observed, indicating system monofractalization.

Ga2O3 layers with thickness from 10 to 86 μm were grown by halide vapor phase epitaxy (HVPE) on GaN(0001)/sapphire templates in a hot wall reactor at 570 °C, with the growth rate of about 3–4 μm h−1. The grown layers consisted of pure (001)-oriented κ-Ga2O3 polymorph with no admixture of β-Ga2O3 or α-Ga2O3 phases. The narrowest (004) X-ray rocking curves were observed for 13–20 μm thick κ-Ga2O3 layers. A further increase in thickness results in deterioration of the crystal quality which is indicated by the broadening of rocking curves. Electrical measurements of the thick layers revealed that they were n-type, with the concentration of shallow donors gradually decreasing from ∼1016 cm−3 to ∼1015 cm−3. Deep level transient spectroscopy (DLTS) measurements revealed the presence of deep traps with levels near Ec−0.3 eV, Ec−0.6 eV, Ec−0.7 eV, Ec−0.8 eV, Ec−1 eV, with the Ec−0.8 eV being predominant.

Purpose of the study: The aim of work is to know how the project activity development dynamics of first-year students of psychological and pedagogical departments could be arranged and prove suggestions of project activity development levels: reproductive, productive, constructive. Methodology: The content analysis method was used which collect data associates with the student's ability to project activities. Main Findings: The work describes results of forming experiment in which seventy-six first-year students of the Institute of Psychology and Pedagogy of Siberian Federal University took part, including 52 people from two experimental groups of psychology-pedagogy occupation and 24 persons from the control group of pedagogy occupation. The results show that the progress in project activity development of experimental group students is vastly different from progress in project activity development of control group students. Applications of this study: Theoretically grounded principles of the organization of the project activities of students in the article can be the basis for the development of specific methods for their implementation in practice. The development levels of project activities — reproductive, productive, and constructive — can be used to monitor the professional competencies of humanitarian students. Novelty/Originality of this study: the article proposes a system for organizing educational and professional activities of a student to build a transition from a student's activity according to a rigid, non-varied plan to a flexible, variable pedagogical project based on the principles of development. This opens up the possibility of becoming a dialogic type of student professionalism already in the process of its preparation.

The paper describes the analysis of long-term fluctuations of aquatic communities (phytoplankton, macrophytes, zooplankton, zoobenthos, fishes) influenced by abiotic factors (water level, salinity) in model lakes of the Onon-Torey plain in Russia. The cyclic succession series are elucidated. These series may provide a basis for monitoring and forecasting the state of the ecosystem for the researched lakes and for other similar lakes in Central Asia.

The article analyzes the rates of credit turnover by branches of the economy and by types of loans using indicators of the dynamic range, indices of average values and aggregate indicators. The purpose of the article is to provide a business case for efficiently managing credit resources in commercial banks based on a factor analysis of credit turnover by sector of the economy as a condition for optimizing a bank’s activities. The analysis of the literature shows that the management of credit resources in commercial banks is limited to the use of Western methods that are not adapted to the Ukrainian reality. The relevance of the article is the need to use the methods of economic and mathematical modeling to optimize the process of managing borrowed funds in the banking industry of Ukraine. Calculated average balances of credit investments. The article analyzes the hourly repayment of interest on loans by enterprises. Calculations of the volume of credit turnover are based on real indicators of the financial statements of Credit Agricole Bank. The study period was elected 2016-2017. Calculated the share of loans by industry in the portfolio of the bank. Defined one-day turnover on the repayment of bank loans by business entities. Calculated the duration of use of bank loans by business entities. The factors affecting the change in the rate of turnover of credit operations using the index method are analyzed. The index of the average duration of use of the loan of a constant composition is calculated. The average duration of use of bank loans by business entities has been determined. The structural change index, variable composition index, constant composition index, structure influence index are calculated. The article used the methods of factor analysis, probability theory, methods of economic and mathematical statistics. The effectiveness of borrowed funds management in the banking industry of Ukraine (on the example of Credit Agricole Bank) was confirmed by the data of a factor analysis of the loan turnover. The system of tasks solved by the proposed models includes the calculation of reasonable limits for attracting each type of resources and the effective interest rate to ensure increasing returns from the production of bank credit products and an increase in the share of the banking sector in creating the gross domestic product of the country. В статті проаналізовано темпи кредитного обороту по галузях економіки і за видами кредитів з використанням показників динамічного діапазону, індексів середніх значень і сукупних показників. Мета статті полягає в економічному обґрунтуванні ефективності управління кредитними ресурсами в комерційних банках на основі факторного аналізу кредитного обороту по галузях економіки як умови оптимізації діяльності банку. Опрацювання літератури засвідчує, що управління кредитними ресурсами в комерційних банках обмежується застосуванням неадаптованих до українських реалій західних методик. Актуальність статті полягає в необхідності використання методів економіко-математичного моделювання для оптимізації процесу управління позиковими коштами в банківській індустрії України. Розраховані середні залишки кредитних вкладень. Аналізується погашення кредитів суб'єктами господарювання. Розрахунки обсягів кредитного обороту спираються на реальні показники фінансової звітності Креді Агріколь Банку. Періодом дослідження обрано 2016-2017 роки. Розрахована частка кредитів по галузях у портфелі банку. Виконано розрахунки одноденного обороту з погашення банківських кредитів суб'єктами господарювання. Розрахована тривалість використання банківських кредитів суб'єктами господарювання. Проаналізовано фактори, які впливають на зміну швидкості обороту кредитних операцій з використанням індексного методу. Наведено розрахунки індексу середньої тривалості використання кредиту постійного складу. Визначено середня тривалість використання банківських кредитів суб'єктами господарювання. Розраховані індекс структурних змін, індекси змінного і постійного складу, індекс впливу структури. У статті використано методи факторного аналізу, теорії ймовірності, методи економіко-математичної статистики. Ефективність управління позиковими коштами в банківській індустрії України (на прикладі Креді Агріколь Банку) була підтверджена даними факторного аналізу оборотності кредитів. В систему завдань, що вирішуються пропонованими моделями, включається розрахунок обґрунтованих меж залучення кожного виду ресурсів і ефективної процентної ставки для забезпечення зростаючої віддачі від виробництва банківських кредитних продуктів та підвищення частки банківського сектора у створенні валового внутрішнього продукту країни.

A change in the surface morphology of recrystallized tungsten foil under the effect of uniaxial tension in ultrahigh vacuum is studied by low-energy electron diffraction and atomic force microscopy. It is found by using low-energy electron diffraction that on the foil surface consisting of separate blocks with dominant face (112), there is a turn in orientation of the structural blocks. The analysis of the topograms of different areas of the side surface of a broken sample, obtained by atomic force microscopy, enabled the association of changes in the atomic structure of the surface layers of foil with a change in its relief by mechanical action.

The atomic structure and surface relief of thin cold-rolled platinum foils upon recrystallization annealing and loading under ultrahigh vacuum conditions have been studied by low energy electron diffraction (LEED), atomic force microscopy (AFM), and scanning tunneling microscopy (STM). The surface of samples upon high-temperature annealing and subsequent uniaxial extension of recrystallized Pt foils represents a fractal structure of unidirectional ripples on various spatial scales. The total fractal dimension of this surface is DGW = 2.3, while the fractal dimensions along and across ripples are D‖ ≈ 1 and D⊥ ≈ 1.3, respectively. The optical spectra of a halogen lamp and a PRK-2 mercury lamp were recorded using these rippled Pt foils as reflection diffraction gratings. It is shown that Pt foils with this surface relief can be used as reflection diffraction gratings for electromagnetic radiation in a broad spectral range.

Samples of Fe70Cr15B15 and Fe77Ni1Si9B13 amorphous alloy foils are loaded at tensile stresses of 0.2–1.2 GPa under constant strain or constant stress conditions. The submicroscopic profiles of the surface are recorded on a scanning tunneling profilometer. The “instantaneous” or extended (in time) transformation of the surface relief is statistically described by calculating the autocorrelation functions of the change in the relief height along two-dimensional scanning paths parallel to the loading axis. The autocorrelation functions thus constructed allow one to estimate the correlation radii of the surface profile, i.e., typical scales of relief components (holes, protuberances, flat regions). The performed analysis has revealed a considerable spatial correlation (∼2 × 103 nm) between the relief components in both initial (unloaded) foils. The application of the tensile load leads to an immediate increase in the roughness of the relief and a sharp decrease in the correlation radius. Subsequently, the relief does not remain stable and changes as a result of competing processes, such as microcrack growth, leveling of bends, and nucleation of kink bands. The behavior of the autocorrelation functions adequately reflects the transformation of the surface profile.

The effect of hydrostatic pressure and uniaxial compression on the relief of an amorphous Fe77Ni1Si9B13 alloy ribbon surface was studied using scanning tunneling and atomic-force microscopy. The fracture surfaces of samples were also studied. It is found that both the initial surfaces and the surfaces of samples subjected to hydrostatic compression or tension, as well as fracture surfaces, are fractal or multifractal, but their fractality parameters are different. Hydrostatic pressure decreases the surface roughness and the average fractal dimension of the surface on both sides of the ribbons. The dependence of the surface fractal characteristics on tension is more complex. Prior to the occurrence of a “critical event” on the surface (formation of a deformation band or a through crack), the Holder index and the half-width of the singularity spectrum decrease. The correlation is discussed between the fractal characteristics of the ribbon surface and those of a fracture surface, and the role of an excess free volume in the initiation of fracture of amorphous alloys is analyzed.

The influence of isothermal annealing on the chemical composition, microstructure, and surface relief of ribbons of an amorphous Fe77NiSi9B13 alloy was studied using Auger electron spectroscopy and transmission electron, atomic-force, and scanning tunneling microscopy. It is established that an annealing below the glass transition temperature results in a boron enrichment of the ribbon surface layer on the side of the ribbon that was not in contact with the roller during quenching. On both sides of a ribbon, islands of crystallized material 2–5 μm in size appear consisting of nano-and microcrystals of α-Fe on the roller-contacting side and of iron boride on the opposite side. The surface relief on the roller-contacting side of a ribbon and that on the opposite side are shown to differ in terms of their spectral and fractal characteristics after annealing. The effect of the chemical composition and excess free volume of the surface layer on the formation of islands of crystallized material and surface relief is discussed.

The effect of mechanical tension on the multifractal characteristics of the lateral surface of a Fe77Ni1Si9B13 amorphous alloy is studied by scanning tunneling microscopy (STM). It is established that, at small loads, the surface is smoothed out much as a crumpled sheet of paper is smoothed out under tension. With an increase in the load, there appears a tendency to the formation of a fractal structure on the surface.

The effect of uniaxial tension in a wide range of applied stress (0–3 GPa) on the surface topography of an Fe77Ni1Si9B13 amorphous alloy was studied by scanning tunneling microscopy. It was found that the distributions of the surface defects with respect to lateral and vertical dimensions exhibit a change manifested by an increase in the proportion of large-scale defects and in the fractal dimension of the surface with increasing load. It is suggested that this surface relief is formed by a diffusion mechanism and that the observed effects are involved in the fracture focus nucleation on the sample surface.

The present work was to build a model of a virtual information space, its functioning is ensured by the creation and implementation of integrated enterprise systems management automation with the latest hardware and software. To achieve the objectives of a specific innovation project and to meet increasing business demands in a competitive environment, you can define different ways to optimize at the expense of modeling the individual stages, as individual sub-projects.

Interferometric methods of sinusoidal, single-frequency phase modulation and two-frequency phase modulation have been investigated and compared as applied to displacement measurements and wavefront testing. A procedure of an experimental estimation of the periodic error which is a basic component of a systematic error of interferometric systems is developed. It is shown that the conventional single-frequency phase modulation method is preferable when it is desirable to have extreme resolution or maximum accuracy, while the method of two-frequency phase modulation will be more rational when small dimensions and weight of the device are of basic concern.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A laser instrument for straightness and alignment measurements with the sliding reflector is described. The instrument provides straightness testing with accuracy of 2im/m at the smoothing time of 3 s.A new method of suppression of the disturbance caused by air turbulence is suggested.

The beam angular divergence meter with CCD camera intended for beam quality test of the excimer laser has been developed. Maximum diameter of laser beam under test is 110 mm. The resolution of the instrument corresponds to diffraction limits. Wavelength region is within the limits 200-1100 nm. Preliminary meter testing has been carried out using the commercial ILGI-503 repetitively pulsed nitrogen laser and the LGN-105 CW He-Ne laser. Performance of the instrument has been demonstrated to be satisfactory both for CW operation mode and pulse operation mode.

A white-light source is used so that good interference occurs only when the two paths are equal, that is, when both primary mirror’s segments are the same distance away from the interferometer, e.g. with a double-image prism in the adaptive telescope. When observing a small step between surfaces with comparable reference dimensions, interference fringes are usually formed in white light that are perpendicular to the boundary line between the surfaces. An interferometer with white-light source is based on a prism design that includes a rectangular prism with a beamspliter hypotenuse face to which an additional prism is cemented to form a double-image compound pentaprism. It makes possible to monitor the step between the elements of a compound primary mirror more simply than in an interferometer with Kosters prism. This is because of the almost complete compensation of the optical path length in a system with counterpropagation of the interfering beams. Preliminary phasing of primary mirror segments during assembling process may be accomplished with help of a such ambiguity sensor. The experimental investigations with visual control showed a possibility to recognize displacement of 1/20 wavelength. This investigation was fulfilled at the special test bench with high resolution laser interferometer. The interferometer resolution is 1 nm.

Phase modulation interferometer with the phase difference computed from the ratio of the first and second harmonics amplitudes has been developed. Signal distortions and deviations of measuring conditions against normal conditions are analyzed and appropriate corrections are made. The instrumental error of small displacement measurements is equal to +/- 0.8 nm (0.95). The digital readout interval is of 1 nm.

The synthesis of carboxylic derivatives of the tricyclic hydrocarbons adamantane and trimethylenenor-bornane by the treatment of the hydrocarbons with formic acid and vinylidene chloride in a mixture of sulfuric and nitric acid is described.