ISSN 0021-3454 (print version)
ISSN 2500-0381 (online version)
Summaries of the issue


The problem of Poisson distribution parameter estimation by results of theoretical researches and limited field tests is considered. In various problems, the Poisson distribution parameter characterizes average number of casual events occur in a set time interval, or average number of points falling into a given space area. The parameter value significantly affects the cost of the developed system and the possibility of its use for a specified purpose. While it is not possible to obtain a sufficient information for evaluation of this parameter during the tests of the system prototypes, invoking an information on the flow of system events accumulated prior to the tests is necessary. A solution to the problem of estimation of the Poisson distribution parameter based on joint processing of a priori information and limited experimental data is presented. 
SYNTHESIS OF POLYNOMIAL CONTROL LAWS FOR CONTINUOUS DYNAMIC OBJECTS Bystrov Sergey V., Grigoriev Valeriy V., Mansurova Olga K., Ivan M. Pershin
For continuous linear dynamic objects with a single inlet and outlet, a procedure of synthesis of polynomial (linear-quadratic) control laws is developed. The use of these control laws can improve the speed of convergence processes for large deviations while maintaining quality indicators processes for small deviations. Synthesis of control laws is based on the use of methods of optimal control theory by solving the Riccati type equation. The control laws are proved not to violate the asymptotic or exponential stability property depending on the type of stability adopted in design.


A standard structure is proposed for system of functional control on the base of logical complements method. The rules of calculation of logical complement functions are established; the rules make it possible to provide a total self-checking of the functional control system structure. Requirements imposed upon the logical device under control are formulated to ensure synthesis of a totally self-checking system of functional control.
A method for measuring aircraft roll with the use of horizontally polarized signals of a radio beacon positioned in a point with known coordinates is considered. The beacon signals are received by an on-board antenna with a polarization modulator implemented in its UHF channel. The modulator is constructed as a rotating circular waveguide section with a half-wave phase plate. The roll angle is determined by the phase of the fourth harmonics of polarization modulation frequency at the output of the single-channel radio receiving device.


Cutting mode parameters for fine milling of hard materials on a multi-axis machining centers in production of space device parts are studied. Interdependence of the treatment process characteristics having the greatest impact on occurrence of parasitic vibrations in the cutting zone is revealed. The influence of cutting speed on parameters of the vibrating activity of the milling system in high speed milling mode is demonstrated. Vibratory activity that occurs during titanium alloy processing with milling machining center is investigated. The energy dissipation coefficient for vibration velocity is determined based on analysis of the data obtained using vibro-compensator in the process of fine milling. Dependence of the loss factor is derived considering the effects for high-speed machining of titanium alloys with application of the damping elements. Basic results of the study of dynamic processes occurring during end milling at high frequency and affecting the dimension processing errors are presented.
ANALYSIS AND SYSTEMATIZATION OF 3D PRINTING DEFECTS Filippov Alexander N., Kopasov Evgeny A., Ivashkova Ksenia P.
Current problems of additive technologies are considered. The importance of automating solution to the problem of elimination of defects of parts produced using 3D printing. A classification of the defects by their origin is presented. Developed facilities. An optional menu for searching instructions used to find a solution to the problem based on the string of the virtual space of the process data is developed.


USING LASER-INDUCED MICROPLASMA FOR MULTILEVEL PHASE PLATE FABRICATION Rumkevich Vladimir S., Roman A. Zakoldaev, Maxim M. Sergeev, Galina K. Kostyuk
Application of the method of processing of transparent materials with laser-induced microplasma to create a multilevel phase plate on fused quartz surface is demonstrated. Optimization of the method for the existing laser system "Minimarker 2" based on Yb-fiber laser with a nanosecond pulse duration (50-200 NS) is described. A software is developed which allows to link parameters of laser treatment with deep relief microstructures, as well as to generate a multilevel phase plate in automatic mode. Based on the results, samples of layered phase plates with binary and discrete structure for testing with He-Ne laser setup are recorded. Comparative analysis of binary and discrete phase plates applied as homogenizers of He-Ne laser radiation is carried out. It is shown that a more uniform distribution of intensity in the beam cross-section is achieved by using discrete phase plate. The proposed method of laser writing of diffractive elements is reported to allow manufacturing of phase plates with a relief depth from 0.1 to 15.0 μm with a step of 50 nm and the minimum size of the cells of 200 μm.
Harnessing of hybrid servers with heterogeneous architecture and computing modules consisting of universal processors, programmable logic integrated circuits, and graphic processors is discussed. The use of heterogeneous architecture is reported to allow to improve efficiency of the solutions of the tasks realized in data processing centers such as web applications, search and indexing of data bulks, hosting of physical and virtual servers, routing, parallel and "cloudy" computation. Results of evaluation of the effectiveness of several applied problems with parallel computing are provided, the problems include: matrix multiplication; operations with big data; search of substrings in data stream in real time on the template which show efficiency of the use of heterogeneous hardware computing environments for their solution. The architecture of heterogeneous multiprocessor hardware and software (MHS) constructed on the basis of an open telecommunication platform and the micro TCA/AMC standard is described; a prototype of the complex has been developed and created in the frames of the project "Development and Organization of Hi-tech Production of Energy Efficient Multiprocessor Hardware-software Server Complexes for the State and Enterprise Information Systems and Data Processing Centers".
GENERALIZED INDICATORS OF ELECTROMAGNETIC DEVICES WITH LEVITATION ELEMENTS Abdullayev Yashar R., Kerimzade Gulshen S., Mamedova Gulaya V., Piriyeva Nadjiba M.
For design of electromagnetic devices with levitation elements (EU with LE) the generalized indicators are established: values of current in the modes of current and efforts, carrying power, the working course, electromagnetic pressure, time of start-off, electromagnetic rigidity and loading capacity. Analytical expressions for the generalized indicators which contain dimensionless quantities are derived to simplify calculations of the proposed indicators and create interrelations between the parameters in explicit form. Recommendations to design of various EU with LE are developed.


Comparative analysis is presented for two alternative ways to create optical waveguide on the base of spatial profiles of refractive index in quartz glass experimentally obtained by femtosecond treatment. Advantages and disadvantages of the two methods in creation of the waveguide core with enhanced refractive index and the cladding with reduced refractive index are discussed. Numerical simulation is employed to analyze the influence of the most significant perturbations observed in the experiment on the basic parameters of the waveguide: the effective refractive index, diameter and shape of the mode distribution, input and output losses for the approval of the mod with standard optical fibers. The following main disturbances affecting the femtosecond record are considered: local decrease in the peak intensity of the laser radiation causing a local reduction of the induced refractive index, and local deviation of the focus point from the desired path for characteristic size of 2 microns. The results of the study can be used to record femtosecond waveguides with reduced losses by scattering, and to increase the repeatability and reliability of the micromachining technology.
EFFICIENCY OF BRAGG GRATING INSCRIPTION BY ArF EXCIMER LASER RADIATION DEPENDING ON ORIENTATION OF BIREFRINGENCE AXIS OF ANISOTROPIC OPTICAL FIBER Varzhel Sergey V., Petrov Andrei Anatolievich, Arkhipov Sergey Vladimirovich, David A. Palanjyan, Munko Anna S., Smirnova Yulia D., Kondakova Nadezhda S.
Recording of fiber Bragg grating by ArF excimer laser radiation is investigated. The record schematic under consideration uses of phase mask method and the possibility of pre-orientation of the birefringence axes of the anisotropic optical fiber. Results of type II fiber Bragg gratings inscription by a single ArF excimer laser pulse in an anisotropic optical fiber with elliptical stress cladding at enhanced concentration of germanium dioxide concentration in the fiber core are obtained at various orientation of birefringence axis. Comparative analysis of the results demonstrates that type II Bragg grating inscription is more effective at the fiber with elliptical stress cladding slow birefringence axis positioning perpendicularly to the laser beam propagation direction. Besides, preorientation of the birefringence axes of the anisotropic optical fiber before the fiber Bragg grating inscription is an effective way to reduce the polarization extinction ratio on the induced optical fiber diffraction structure.
FIBER BRAGG GRATINGS INSCRIPTION USING TALBOT INTERFEROMETER AND KrF EXCIMER LASER SYSTEM Alexey I. Gribaev, Varzhel Sergey V., Kirill A. Konnov, Stam Arseny M., Idrisov Ravil F., Slozhenikina Yulia I.
An experimental setup for the fiber Bragg gratings inscription using Talbot interferometer is described. A KrF excimer laser system CL-7550 of the type “Master Oscillator – Power Amplifier” by Optosystems Ltd., Russia, with enhanced spatial and temporal coherence is applied as the UV radiation source in the experimental setup, which includes laser beam transportation optical system and Talbot interferometer. To ensure the effective recording, the laboratory setup also includes spectral width control system based on Fabry Perot interferometer, laser beam energy distribution control system, monitoring system of laser pulse energy density on the optical fiber, and control system of optical fiber to the laser beam relative position: spectral width control system, based on Fabry-Perot interferometer; laser beam energy distribution control system; monitoring system of laser pulse energy density on the optical fiber; and control system of optical fiber to the laser beam relative position. Results of type I fiber Bragg gratings inscription in single-pulse and multi-pulse modes are presented. Dependence of spectral characteristics of fiber Bragg gratings on various recording conditions are analyzed. A method for experimental investigation of optical fiber relative photo-refractivity is described.
LASER PROCESSING OF GLASSY CARBON TO OBTAIN THE EFFECTIVE EMITTING STRUCTURES Ivan A. Popov, Tatiana N. Sokolova, Elena L. Surmenko, Yury V. Chebotarevsky, Bessonov Dmitry A., Shesterkin Vasiliy I.
Special techniques and algorithms of laser forming of emitting structures on the glassy carbon SU-2000 surface are described. The structures of pillar-shaped tips with semicircular apexes and the structures of separate needle-shaped tips with a high aspect ratio are considered. Formation of the tips on the plate is carried out in several stages, each of which used a separate bypass program of the treated surface by the laser beam and different processing parameters. To create the pillar-shaped tips the sequential layerby-layer laser milling is carried out: on the first stage a truncated cone with a flat top is formed, on the second a rounding is created, on the third micro-structuring of the surface of spherical tips is performed. Formation of needle-shaped tips is carried out also in three stages: firstly, the rough milling of the tip cylinder is carried out, on the second stage of thin processing the needle-shaped tip is milled, and on the third stage laser cleaning of the tip surface is implemented. As a result, the matrixes of microtips are obtained with packing density N≈2×105 cm-2 on the spherical apexes of field-emission cathodes and the needle-shaped tips with an aspect ratio about 500.