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

INSTRUMENTS AND SYSTEMS OF AUTOMATIC CONTROL

PROBLEMS OF DEVELOPMENT OF CONTROL SYSTEMS OF GAS-PRODUCING COMPLEXES Sergey E. Abramkin, Dushin Sergey E., Dmitry A. Pervukhin
685
The problems arising in the development of control systems of gas-producing complexes are consi-dered and ways to overcome them are analyzed. It is noted that the unsteady and random nature of gas production processes affects the definition of the field development mode, assessment of technological parameters, optimization of gas production and treatment processes. The gas production complex is characterized by the presence of different types of reservoir filtration systems, simultaneous and separate production from several layers, different types of collection structures and gas treatment technologies. The objective function of the control system is defined as the assurance of a given performance under the conditions of hydrate formation prevention, which is achieved by providing the required gas indicators for moisture and hydrocarbons. By controlling the gas pressure at the outlet of the installation, the necessary conditions for the operation of gas transportation systems are created and the maximum use of gas reservoir energy and the capacity of the section of the main gas pipeline is ensured. A concept of cybernetic systems is proposed; this concept consists in formation of two interconnected and interacting in real time dynamic subsystems striving for self-organization. Within the framework of the concept, it is necessary to develop digital models of controlled gas production processes at gas wells, gas production in multi-layer deposits using a single well, rectification of multicomponent mixtures and multi-mode control systems, taking into account the analysis of a large array of data on modes.
693
The necessity of creating a system of air signals of an airplane with one fixed non-protruding re-ceiver of incoming air flow is substantiated. Features of the airborne signal system of an airplane with a fixed non-protruding receiver of the incoming air flow, which are based on an ion-tagged aerodynamic angle sensor and true airspeed with a static pressure receiver hole on its streamlined surface, are revealed. Algorithms for processing information in the measuring channels of the system are presented, methodical static errors of the system for measuring air signals of an aircraft with a fixed non-protruding receiver of the air flow and technologies for their reduction are evaluated, the causes of such errors are analyzed.

COMPUTER TECHNIQUE

QUANTUM FORMALISM METHODS IN INFORMATION RETRIEVAL AND PROCESSING OF TEXTS IN NATURAL LANGUAGES Bessmertny Igor Alexandrovich, Alexey V. Vasiljev, Koroleva Julia A., Alexey V. Platonov, E. A. Poleschuk
702
Creation of intelligent systems in the paradigm of logical decision-making requires formalization of knowledge in the form of ontologies, production models, etc. However, a rigorous formalization of knowledge is far from always possible due to the incompleteness, inaccuracy, and inconsistency of the data. In this regard, recently, the attention of researchers has shifted to extracting knowledge from natural language texts. Particularly noteworthy is the recently developing approach based on the use of quantum formalism to the objects of the macrocosm, which allows one to consider the uncertainty and inaccuracy inherent in the natural language. Numerous experiments conducted over the past 30 years demonstrate that the mathematical apparatus developed for modeling elementary particles also satisfactorily describes the behavior of people, which cannot be described by the mathematical apparatus of classical logic and probability theory. A review of the methods of processing natural language texts by means of quantum mathematics is presented. The methods are designed to eliminate the shortcomings of existing methods and means of information retrieval.
710
A hybrid transformation method is proposed for the problems of analyzing nonlinear dynamical sys-tems of polynomial structure. The method is based on polynomial transformations and allows for analyzing analytically the properties of stationary solutions for systems in normal and extreme operating conditions; for non-stationary (e.g., transition) solutions, it may be used in conjunction with the Runge-Kutta numerical method. The method has significantly less computational complexity than numerical methods of an equivalent degree of accuracy and does not require determination of conditions and domain of convergence of the approximate solution. It makes it possible to calculate characteristics of various technical objects under external periodic influences. As an example, the method of transformations is used to study a dynamic model of truck crane and to carry out the calculations for vibration-proof systems of boat motors.

OPTICAL AND OPTO-ELECTRONIC INSTRUMENTS AND SYSTEMS

STUDY OF PHASE PLATES ERRORS IN A STOKES POLARIMETER Dmitrу E. Kukushkin, Bakholdin Alexey V., Victor D. Bychkov, Gennady G. Valyavin
717
An optical schematic of the Stokes polarimeter developed for the high spectral resolution spectro-graph of Large Telescope Azimuthal is presented. The passport errors of the phase plates used in the polarimeter are given. A model of the phase plates operation based on Muller matrices is described and discussed. A comparison of the model with the results of measurements of the fabricated phase plates is carried out. The instrument polarization of the manufactured phase plates is estimated. Произведена оценка инструментальной поляризации фазовых пластин. As a result of numerical simulation, the er-rors of the Stokes parameters measurements are obtained.
729
Optically induced defects in photorefractive crystals are studied. The possibility of application of polarization-interference method is considered. The experimental conditions for studying photoinduced defects in lithium niobate crystals by analyzing the polarization interference are formulated. A technique is proposed that allows for determination of the photoinduced birefringence value of a crystal in the region of the induced defect by the level of light intensity transmitted through the system. Schematic diagram of an experimental setup for studying the kinetics of the photoinduced defects formation in uniaxial crystals is presented.
734
The quality function is proposed to use as a target function in calculation of interference coating pa-rameters. An algorithm is presented which determines the design of interference coating to provide a specified energy reflectance or transmittance in a certain wavelength range, with the additional condition of insensitiveness or low sensitiveness of the spectral characteristics to deviations in the layers’ parameters. The proposed algorithm efficiency is confirmed by analysis of obtained coating design.

SCIENTIFIC AND PRACTICAL DEVELOPMENTS

741
In St. Petersburg Nuclear Physics Institute, on the basis of the WWR-M reactor, a high-flux source of ultracold neutrons is created with liquid deuterium as a pre-moderator of reactor neutrons. Results of calcu-lations of liquid deuterium convective flow in the source's deuterium capsule are presented depending on the heat flux and boundary conditions. The structure of the flow, temperature field, and velocity of liquid deuterium in the source of ultracold neutrons are numerically studied. The possibility of providing the thermal regime of a deuterium chamber with a heat flux power of up to 850 watts is proven. The dependence of the flow structure on the boundary conditions is analyzed. The influence of this dependence on the velocity field and heat flux is revealed.
749
A control over parameters of the internal special thread of the nut part included in the design of a roller screw transmission of an electromechanical drive is a difficult metrological task and is possible only using modern coordinate measuring equipment. The main problems associated with the control of the parameters of high-precision internal thread are considered. Methods of controlling the parameters of the internal thread are analyzed, measuring equipment that meets the accuracy requirements is selected, a method for evaluating the parameters of the internal special thread of the nut part is developed. The presented technique allows a full assessment of the thread parameters (pitch, average diameter, and the profile in axial section) based on the use of a contour meter with a double-sided probe. An algorithm of the analysis of the thread contour using the measured parameters is described.
DEPENDENCE OF THE REFRACTIVE AND ABSORPTION INDICES ON NANOSCALE LIQUID FILM THICKNESS Nickolay V. Novozhilov, Nickolay Yu. Sdobnyakov, Ilya D. Rodin
758
Based on the spectrum analysis of the ellipsometry angles obtained with photometric spectral ellipsometer «El`f», an investigation of size dependences for the refractive index and absorption index of nanosized ethanol film deposited on a silicon substrate and a glass substrate is performed. The refractive index is found to decrease monotonically with the film thickness in the thickness range under investigation. In the region of 85–140 nm for the glass substrate and 120–150 nm for the silicon substrate, a rather sharp decrease in the absorption coefficient was observed with a decrease in the film thickness. It is assumed that for the refractive index such an effect occurs only in the range of smaller film thicknesses.