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

INFORMATION TECHNOLOGIES AND SYSTEMS, COMPUTING TECHNIQUE

5
Methods of creation of codes with summation focused on detection of errors in data vectors, are investigated. The ways to modify classic and modular sum codes are analyzed. It is noted that in some cases of a modified sum code building, it may be effective to choose the account module in the form of an arbitrary natural number M>2. An overview of the sum codes properties is presented; several previ-ously unknown features of modified sum codes with arbitrary account modules are established. The consideration concerns not only the features of detecting errors of different multiplicity, but also of differ-ent types (monotonous, symmetric and asymmetric). Detailed analysis is given to modified sum codes with arbitrary account modules having the best error detection characteristics in the code family with a specific module. The advantages and disadvantages of the code class in question are discusses. Pro-spects for cods application in solving the problems of synthesis of controllable automation devices and systems are formulated.
18
A method of balancing the sensitive element of pendulum accelerometer by laser evaporation of a metal is presented. The process of adjusting the balancing load of the micromechanical accelerometer for the lower and upper positions of the sensor element in relation to the vertical is considered. A physi-cal pendulum serves as a sensitive element of the device. When using a micromechanical pendulum accelerometer as a sensor, the threshold sensitivity determines the sensitivity of the micromechanical accelerometer to the slope of the base in the field of gravity. Calculated formulas for the lower and upper positions of the pendulum are derived. For the practical implementation of this method, it is proposed to use the technology of laser evaporation of material from the surface of the balancing load.

INSTRUMENTS AND SYSTEMS OF AUTOMATIC CONTROL

26
The problem of controlling a highly maneuverable aircraft capable of changing its position in space by modifying the velocity vector in magnitude or direction is considered. A rational algorithm de-veloped for governing an automatic flight control system that does not exceed the main operational limits is presented. For this purpose, in addition to channels for stabilizing the angular position, channels for limiting the specified parameters are included in the aerobatic circuit that controls movement around the center of mass of the aircraft. A method is proposed for ensuring the coordinated interaction of these channels in the switching mode by using a generalized system characteristic that allows describing the entire ensemble of output reactions of the system for all possible moments of change in the structure of the control part. The effectiveness of the proposed approach is confirmed by the results of modeling the synthesized system of automatic control of the angular position of the aircraft.
35
Results of development of a method for evaluating the accuracy of autonomous system of spacecraft navigation and orientation are presented. Advantages of the autonomous approach and the current state of the theory and practice of modeling the processes of functioning of autonomous spacecraft navigation systems are considered. The proposed method allows to provide a sufficiently high accuracy of ephemerides, which is maintained for a long time. Results of estimation of orbit parameters for various algorithms for solving navigation problems obtained with the use of the developed automated system of scientific research are demonstrated.

OPTICAL AND OPTO-ELECTRONIC INSTRUMENTS AND SYSTEMS

INFLUENCE OF STAND MODULE CHARACTERISTICS ON THE ERROR IN DETERMINING PARAMETERS OF VIDEO CAMERAS WITH MATRIX CMOS PHOTODETECTORS Dinh Ba Minh , Korotaev Valery Viktorovich, Alexander N. Timofeev, Yaryshev Sergey Nikolaevich
46
A structure of an experimental stand for studying parameters of serial digital video cameras based on matrix CMOS photodetectors is proposed. Requirements for the characteristics of the test bench elements in determining the uneven sensitivity of the photodetector section and evaluating the signal-to-noise ratio when changing the irradiation level and exposure time are justified.
HARDWARE AND SOFTWARE COMPLEX TO ASSESS THE COLORED STONES RAW MATERIAL QUALITY, ITS CLASSIFICATION AND CERTIFICATION Chertov Alexander N., Gorbunova Elena V., Peretyagin Vladimir Sergeevich, Artem A. Alekhin , Anastasia S. Kushkoeva, Yuriy M. Morozov
55
The necessity to move from subjective parameters for evaluating the quality of colored stones to objective ones is discussed. An automated hardware and software complex based on the methods of technical vision and image processing and intended for determining in quantitative form such indicators for assessing the quality of colored stones as "size", "color", and "purity" is developed. A description of the developed complex is presented. On the example of beryllium raw materials, the possibilities of quantitative evaluation, packaging and certification of analyzed samples of colored stones are shown. The proposed technical solution can be used by mining and jewelry companies, markets and auctions, gemological centers, and state authorities.

INSTRUMENT-MAKING TECHNOLOGY

METHODS FOR MOUNTING CRYSTALS IN THE SILICON TRANSISTOR STRUCTURES PRODUCTION Tagir A. Ismailov, Aishat R. Shakhmayeva, Biyke A. Shangereeva, Tazhutdin E. Sarkarov
61
Various methods of attaching crystals to semiconductor device housings are presented. The quality of solder contacts depends significantly on the formation of connections between the solder components and the metal coating. For soldering silicon crystals, POS-5 solder is used, which corresponds to the melting temperature and a narrow temperature range of solidification, which ensures that there is no shrinkage porosity in the solder joint. Results of tests of POS-5 alloy wire on solderability of transistor structure crystals are presented.
METHOD OF BALANCING THE SENSITIVE ELEMENT OF MICROMECHANICAL PENDULUM ACCELEROMETER Tkalich Vera L., Mariia E. Kalinkina, Pirozhnikova Olga I., Korobeynikov Anatoliy Grigorievich
70
A method of balancing the sensitive element of pendulum accelerometer by laser evaporation of a metal is presented. The process of adjusting the balancing load of the micromechanical accelerometer for the lower and upper positions of the sensor element in relation to the vertical is considered. A physi-cal pendulum serves as a sensitive element of the device. When using a micromechanical pendulum accelerometer as a sensor, the threshold sensitivity determines the sensitivity of the micromechanical accelerometer to the slope of the base in the field of gravity. Calculated formulas for the lower and upper positions of the pendulum are derived. For the practical implementation of this method, it is proposed to use the technology of laser evaporation of material from the surface of the balancing load.

SCIENTIFIC AND PRACTICAL DEVELOPMENTS

78
A method for estimating the wear resistance of materials on a friction tire is presented. The meth-od is based on the principle of embedding the disk in a flat sample and calculation of wear and specific pressure along the length of the formed chord on the top of the bar during the tests. An algorithm for cal-culating the wear resistance of materials is developed, which allows estimating linear, mass and volume wear along the length of the chord. Results of tests of samples of various materials for wear resistance, carried out with a constant load, but at variable pressure, are presented. The test conditions allow to test materials of any hardness and evaluate the relative wear resistance in a short period of time, taking as a reference a sample of one of the materials, such as steel 40.
84
The possibility of improving the aerodynamic quality and reducing the radar visibility of low-flying vehicles due to rounding the low-frequency components of sea waves in the vertical plane is considered. It is shown that it is possible to minimize the height of a low-flying vehicle near the sea surface due to vertical maneuvering, while maintaining a given level of safety, which allows improving the aerodynamic quality. The potential possibility of reducing the average height of the vehicle when driving in conditions of 4 - and 6-point irregular sea waves and the amount of re-loading that occurs during maneuvering are estimated by simulation. The proposed method can be implemented in the control systems of low-flying vehicles and used if it is necessary to minimize the speed and tolerance of long-term movement with minor overloads.