### REVIEW

RING PULSE GENERATORS IN DIGITAL INFORMATION DEVICES
Valery A. Chulkov

5

An overview of the development of ring pulse generators for digital measuring transducers is presented. Among others, devices based on user-programmable gate arrays are considered. Basic structures of the ring oscillators are presented, as well as design options of their cascades with the ability to control delay time and, therefore, stabilization and regulation of the frequency of the pulses. Methods and technical implementation of digital and analogue adjustment of vibration frequency with the use of advanced interpolation are described. Recommendations on construction of time—code converters based on the valve matrix programmable by the user are formulated.

### DEVICES AND SYSTEMS OF AUTOMATIC CONTROL

METHOD OF ACCELERATED SIMULATION OF NETWORK SWITCHING NODES
Kutuzov Oleg I. , Tatarnikova Tatiana M.

23

An approach is proposed for decomposition of switching node into virtual commutation channels connecting the transmitting and receiving node ports. The developed simulation model of a specific data transfer path between the ports of the switching node preserves the interrelation of parameters and transmission processes between all node ports. The proposed approach allows to reduce dimension of the switching node simulation model. By the example of virtual switching channel, as an analog of the switching node, it is demonstrated that application of the layered modeling method speeds up the modeling process. Presented results show the efficiency of joint application of the layered approach and the reduction of the switching node model dimension.

APPLICATION OF FUZZY AND NEURO-FUZZY CONTROLLERS
IN THE CONTROL SYSTEM OF TWO-MASS OBJECT WITH NONLINEAR DISTURBANCES
Dmitry V. Lukichev , Kuzin Aleksey Yu, Galina L. Demidova, Sergey Yu. Lovlin, Ivan Zhdanov

32

A method of synthesis and analysis of control algorithms based on fuzzy logic and neural networks is presented. A two-mass electromechanical system with a nonlinear perturbation in the form of a dry friction torque is used as an example. Behavior of the synthesized system under the influence of the wind torque is studied. Robustness of the systems with variation of the second mass inertia as a parametric disturbance is analyzed. The analysis of the obtained results allows to estimate the expediency of application of the considered algorithms.

### COMPUTING TECHNIQUE

CORRECTNESS OF MARKOV MODELS
WITH DISCRETE STATES AND CONTINUOUS TIME
Shcheglov Konstantin A, Shcheglov Andrey Yu

40

Questions of correctness of Markov models with discrete states and continuous time characterized by independence of input random events are investigated. It is proved that the countable model is correct if it realizes the requirements formulated in the work. Requirements are formulated and approaches to the transformation of the accounting model into a correct final model with and without losses are substantiated.

MERGING OF SEMANTIC NETWORKS BASED ON EQUIVALENCE OF TOPOLOGIES
Pismak Alexey E., Klimenkov Sergey V. , Tsopa Evgeny A, Artem Yu. Slobodkin, Vladimir V. Nikolaev

50

A method realizing of semantic graphs merging algorithm based on features of their topologies is presented. The method application results in creation of a semantic network of high connectedness formed from two heterogeneous sources.

### OPTICAL AND OPTO-ELECTRONIC INSTRUMENTS AND SYSTEMS

VISUALIZATION OF GAMMA-RAY SOURCES
USING THE SCINTILLATION METHOD AND CODING APERTURE
Vasilieva Anna V., Victoria A. Ryzhova, Vasiliev Alexander S

56

Theoretical aspects of gamma image formation based on the scintillation method with the use of solid-state silicon photoelectron multiplier and coding aperture are considered. The physical processes occurring in the scintillator under the action of ionizing radiation and leading to generation of visible radiation are discussed. The effective cross sections of the photoelectric effect, Compton scattering, and electron-positron pair generation are calculated depending on the gamma-quantum energy. Parameters of several scintillation crystals with different physical properties and gamma-ray attenuation efficiency are presented. Principle of operation of the coding aperture intended for formation of gamma image is considered, and ways of realization of its various configurations are described. A block diagram of a gamma-radiation visualization system providing high visibility and efficiency of gamma sources monitoring is proposed.

NEW FAST ALGORITHMS FOR RESTORING OBJECTS IMAGES SMEARED AT AN ANGLE
Sizikov Valery S , Andrey A. Sergienko, Nina G. Rushchenko

69

Two new fast algorithms for solving ill-posed one- and two-dimensional Fredholm integral equa-tions of the first kind by Tikhonov regularization are presented. In both algorithms, the speed increase of solving integral equations of convolution type is achieved by using fast Fourier transform and preliminary calculation of several spectral functions. The difference between this work and the previous ones is that the image smearing is considered at an angle with respect to the horizon, which requires special approaches. The proposed algorithms can be used to quickly restore images from blurred images of moving objects. A numerical example of a fast (about 1 s) restoration of an angle-smeared image of an aircraft is given.

### INSTRUMENT-MAKING TECHNOLOGY

FEATURES OF MACHINERY EQUIPMENT FOR COMPLEX WINDING OF OPTICAL FIBER
Vyacheslav A. Loparev, Kiselev Sergey S., Shilin Mikhail M.

78

The factors that complicate the winding of fiber-optic cable, in particular rocket fiber, such as fiber stiffness and sensitivity to mechanical stress, are considered. For complex winding of the optical fiber, a variant of the machine is proposed. An experimental winding has been performed using the proposed equipment. Distinctive features of the developed machine are winding along the cone forming with the use of a clamping roller and a binder, control of tension and position of fiber laying. These solutions make it possible to form a frameless contour of a fiber-optic micro cable that is resistant to external mechanical influences.

IMAGE OF THE SURFACE PROFILE AS A GRAPHIC CRITERION OF ITS ROUGHNESS
Gibadullin Ilsur N., Valetov Vyacheslav A.

86

A method of estimation and control of surface roughness of instrument parts using graphical criteria is proposed. In particular, image of surface profile may be used as the criterion. To implement the method, a special software is developed to qualitatively assess the degree of similarity of profiles of the surfaces under consideration. Results of the study of application possibility of the developed technique to real surfaces obtained by various processing methods are presented.

ELECTROMECHANICAL GRIPPER WITH FORCE SENSING SYSTEM
Margun Alexei A., Bazylev Dmitry N, Zimenko Konstantin A., Polina D. Vakhviyanova

93

An electromechanical underactuated gripper with flexible joints and a force sensing system is presented. The gripper is characterized by small size, weight, and energy consumption, which allows it to be used on mobile robotic devices. The key advantage of the developed device is the expansion of the field of application due to the proposed force sensing system enabling operation with fragile and inelastically deformable objects, as well as with objects of complex geometric shape. Another feature of the proposed gripper is the use of additive technologies for manufacture of parts that provide rigidity and structural integrity.