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

INFORMATION TECHNOLOGIES AND SYSTEMS

415
The problem of prioritization in single-channel queueing system with non-uniform flow of demands is considered for the case of certain constraints on probability of permissible service time excess for demands of various classes. A solution to the problem is obtained in the class of queueing disciplines with mixed priorities specified in the form of priority matrix. The matrix elements represent the type (relative or absolute) and the level of priorities for demands of various classes. The algorithm of prioritization is based on purposeful search of queueing disciplines, the system productivity serves as the discipline effectiveness indicator.
421
Results of investigation on recognition of signals with similar time-and-frequency structure are presented. Arranged sequences of signals wavelet coefficients are proposed to be used as indicators for the signals recognition. Feasibility of wavelet coefficients synthesis based on frame transforms is justified. Computer simulation data are analyzed. Basic stages of the algorithm realizing the proposed approach are determined.
ERROR ESTIMATION FOR A FAST METHOD OF SPECTRAL ANALYSIS Nuraddin Ya. Mamedov, Namik T. Abdullaev, Gunel S. Agaeva, Dzhapharova Ainur N.
428
A method of spectral analysis is proposed for digital processing of measuring signals. Theoretical expressions for relative error of measuring signal transformation are derived. Sharp estimates of the error depending on differential and spectral properties of the measured signal are obtained. Application of the estimates makes it possible to justify the proposed method and to assure the desired accuracy of its realization.
APPLICATION OF FACTORIAL SYSTEM TO COMBINATORIAL PROBLEMS SOLVING Vladimir I. Polyakov, Skorubskiy Vladimir I, Ekalo Yury V.
436
Properties of the factorial number system are analyzed and several new fields of its application to combinatorial problems in programming and computer systems design are considered. Factorial numbers may be univalently enumerated with decimal or binary integers and interpreted as permutations of elements of any type. Decoding of binary-coded record of permutation in the factorial number system makes it possible to relate each permutation to a unique distribution of discreet objects (elements, references, etc.) in a specific discreet space. Permutations and distributions may be used in solving the problems of automation of design and commutation of calculating system channels, as well as in data protection.
443
A method of the speech signal parameterization providing emotion-tolerant and speaker-invariant feature vector is proposed. The method makes use of the cepstral coefficients defined on an ExpoLog frequency scale on the base of on a linear-prediction power spectrum. The described feature vector is applied for emotional speech recognition based on hidden Markov models. Experimental results demonstrate that the use of the proposed method improves emotional speech recognition efficiency by 5,9 %.
451
An algorithm for determining the initial states of the shift registers with linear feedback, incorporated into the device generating Gordon—Mills—Welch sequences, is developed.

ELECTRONIC AND ELECTROMAGNETIC DEVICES

458
Mechanical transient processes in single-engine and two-engine three-mass mechanisms of executive axes of servo drives of support-rotating systems are considered. Vector – matrix mathematical models describing the processes are proposed. Formulas for calculation of resonance frequencies are presented, the model data are confirmed by results of spectral analysis of the transient processes carried out with the use of MatLab package. Transformation of initial models with the use of electric analogy method allows calculating parameters of equivalent two-mass models of two-engine servo drives with three-mass mechanisms of the axes. The results provide a basis for selection of structure design and development of rigorous method for synthesis of control systems of telescope servo drives with two-engine three-mass mechanisms of the axes.
464
A circuit of high-frequency commutation of capacitors allowing for smooth variation of their equivalent capacitance is studied. A limiting continuous model of equivalent capacitance regulation circuit is developed. Results of digital modeling demonstrate practical equivalence of the model and actual circuit for the case of high enough commutation frequency.

OPTICAL AND OPTO-ELECTRONIC INSTRUMENTS AND SYSTEMS

MONITORING OF OPTICAL PROPERTIES OF CARBAMIDE AQUEOUS SOLUTIONS WITH THE USE OF INDUSTRIAL REFRACTOMETRY Vasiliy Artemiev, Nikolay P. Belov, Lapshov Sergey N., Andrey V. Smirnov, Sherstobitova Alexandra S., Yaskov Andrey D., Odnovorchenko Pavel V.
473
Concentration and temperature dependences of the refractive index, n(md, t), of carbamide aqueous solutions, as well as the index temperature factor, dn/dt , are measured. Industrial model of refractometer designed for monitoring of concentration of carbamide aqueous solutions in production line, and programmable method of the refractometer adjustment and calibration are described. Interpolation expressions for the refractive index ad its temperature coefficient are derived. Results of numerical simulation of short-wave absorption spectra are presented.
478
A method for determining the position of small arm sight line is proposed. The method is based on correlation between relative coordinates of target mark image and absolute coordinates of referent light beam.

INSTRUMENT-MAKING TECHNOLOGY

CONTROL OVER RASTER IMAGE CONTRAST IN LASER MARKING: TECHNOLOGICAL PROCESS MODELLING Yulmetova Olga S., Shcherbak Alexander G. , Veiko Vadim Pavlovich, Raliya Yulmetova, Shcherbak Sergey A.
485
A method is proposed for evaluation of conditions and variation interval for laser surface treatment parameters in laser marking of raster images on spherical electrostatic gyroscope rotors. The method makes it possible to manage the raster image contrast at retained accuracy of hundredths of a micrometer. The contrast simulation code is developed on the base of a model of contrast management process in the form of successive stages associated with the procedure of choosing the optimal approximating function. Nonparametric approximation is used at the first stage, when only the most general information on the dependence under investigation is available. At the second stage the model of the dependence is supposed to be known, a parametric approximation is performed and a quantitative indication of the model parameters is carried out. Application of the proposed model for laser marking for the general case and for a particular labeling of thin-film coating of titanium nitride is justified. A family of curves defining the contrast dependence on the laser power for various stoichiometric composition of titanium nitride TiNx (x = 0,80—1,00) is presented. Results of the practical use of the technology are presented.
492
A parallel-axis toothed gear with approximate tooth profile is studied. The problem of optimal choice of geometric parameters in the absence of edge contact is solved with the use of calculations performed on the base of developed model of rod-toothed transmission.

BRIEF NOTES

498
Practicable results of investigation of a five-layer quarter-wave antireflection coating are presented. The coating is shown to exhibit a low reflectance in the visible and near infrared spectral ranges.
501
Error of object location by optical-electronic position-control system with polychromatic equisignal zone with the use of the dispersion method is considered. A component of the error which may not be eliminated is found. The component is shown to depend on the system optical parameters, distance to the object under control, and the used wavelengths. Results of numerical simulation reveal a possibility to reduce the error component by optimization of the optical system parameters.