2687-0517 11 1 2018 1-78

RAR RUS 7-17 Peter the Great St.Petersburg Polytechnic University Sivchek Igor cotgreat@gmail.com

Polytechnicheskaya, 29, St.Petersburg, 195251, Russia

Outphasing modulation in a series circuit with Сhireix compensation in class EF2 The paper presents a model of the radio transmitter output stage for generating signals with high peak-to-average ratio waveform (AM, single-sideband modulation, QAM), based on a series outphasing modulation circuit with Chireix compensation and class EF2 power amplifiers (PAs). The property of the class EF2 PA to maintain high efficiency when complex load resistance varies over a wide range is shown. It allows to preserve high efficiency of amplitude modulation at 15 times power back-off. Due to a higher power output capability than in a Chireix outphasing circuit with class E PAs, the proposed circuit can be widely used in broadcasting (short wave AM and DRM) and communication (WCDMA and LTE) transmitters with different output power levels and frequency ranges.   10.18721/JCSTCS.11101 621.396.61 transmitter output stage outphasing modulation Chireix compensation power amplifier (PA) class EF2 https://infocom.spbstu.ru/article/2018.56.1/ 01.pdf

RAR RUS 18-27 Gazpromneft STC Krasnov Fedor krasnov.fv@gazprom-neft.ru Institute for High Pressure Physics RAS Butorin Alexander Butorin.av@gazpromneft-ntc.ru Institute for High Pressure Physics RAS Mikheyenkov Andrey V. mikheen@bk.ru Reconstruction of medium reflectivity coefficients based on seismic data through machine learning Geological models of Digital oil fields (DoF) require information about structural properties of subsurface media. 3D models of structural properties of subsurface media are based on data from field seismic survey. Seismic survey is one of the few universal geophysical methods of obtaining information of the Earth subsurface. A reflected signal as a part of seismic data provides information of the properties of a medium through which it has passed. Reflectivity coefficients are determined by fluctuation of the medium’s elastic properties and serve as a basis for interpretation of seismic data as well as for prediction of geological structures. We have developed a new method of processing seismic data which allows to locate reflecting planes and compute values of reflectivity coefficients with high degree of precision. To resolve this problem, we have used the Semi-supervised learning method. The machine learning method made it possible to develop a mathematical model, optimize its parameters for synthetic data in order to further use the model for unmarked-up seismic data. The main novelty is in developing a learning algorithm using signal convolution and reflectivity coefficients’ regularization. The model we have developed demonstrated high precision for synthetic seismic data with high density of reflecting planes (103 planes per a second of trace). The resulting low level of errors allows significant improving of quantitative understanding of the subsurface structure based on seismic data and is a firm basis for building geological models. 10.18721/JCSTCS.11102 316.452 seismic data machine learning optimization problem reflection plane position signal processing dictionary learning https://infocom.spbstu.ru/article/2018.56.2/ 02.pdf

RAR RUS 28-37 Peter the Great St.Petersburg Polytechnic University Kvasnov Anton V. AntonKV@mail.ru The method of identifying radar target marks from active and passive stations by means of Z-test The article describes a method of identification of target marks received by combined passive and active radar stations. The method is based on Fisher's Z-test, which allows to statistically test the hypothesis of belonging (or separate observation) of detected objects. The basis of this method are the statistical distributions of bearings obtained with passive and active stations. A mathematical model of the Z-test is builton the basis of assumptions about the deviation of the distribution of the active station’s bearing from the distribution of the total population of the passive station. We have established the conditions providing the execution of the method, as well as the restrictions that do not allow to use the Z-test. We have considered an algorithm of consecutive application of the method and have conducted a simulation with MatLab 2012, which proved the method’s effectiveness in combined radar complexes. 10.18721/JCSTCS.11103 621.396.96 identification marks of the target radar information Fisher’s Z-test form of the target radar complex https://infocom.spbstu.ru/article/2018.56.3/ 03.pdf

RAR RUS 39-46 Peter the Great St.Petersburg Polytechnic University Igor G. igcher@spbstu.ru

Polytechnicheskaya, 29, St.Petersburg, 195251, Russia

Peter the Great St.Petersburg Polytechnic University Kotlyarov Vsevolod vpk@spbstu.ru Implementation of nonlinear programming second order methods on the basis of recurrent estimation algorithms A method of goal function second derivatives approximation is developed. It is based on the recurrent least squares method and the modified Kaczmarz algorithm. The technique allows to use highly effective methods of second order, for example, Newton type without additional computational costs to build finite difference approximations of derivatives or other direct methods of derivative calculation. The developed technology is focused on solving convex and non-convex nonlinear programming problems. The two approaches to constructing a recursive procedure for estimating second derivatives can be applied to second-order methods of nonlinear programming. Thus, the starting point of the Hessian is computed (approximated) directly, for example on the basis of finite difference approximations of derivatives. Next, while running the chosen second-order method, the matrix of second derivatives is consistently updated and refined based on the proposed technologies, allowing the significantly reduce the computational costs. 10.18721/JCSTCS.11104 681.3.06 recurrent least squares method; the modified algorithm of Kaczmarz; nonlinear programming; nonconvex problems; the second order optimization methods https://infocom.spbstu.ru/article/2018.56.4/ 04.pdf

RAR RUS 47-64 Solomenko Institute of Transport Problems of the Russian Academy of Sciences, University National Technology Initiative 2035 Seliverstov Yaroslav maxwell_8-8@mail.ru University of Civil Aviation Gergel Gleb Glebgergel@yandex.ru Institute of oriental manuscripts of Russian Academy of Sciences Seliverstov Sviatoslav amuanator@rambler.ru Peter the Great St.Petersburg Polytechnic University Nikitin Kirill execiter@mail.ru Improvement of intellectual transport systems by mobile technologies and procedures of analysis of social activity of urban population We have analyzed cellular communication as part of intelligent transport systems to collect information on traffic flows and mobility of the population. A model of the monitoring system of social activity of urban population is developed in the set theory interpretation. The reliability of the model is demonstrated on the example of the mobile application «City Navigator». The application is developed in the Xcode 9 environment in Swift 3, and the data analysis system is developed in Python 3.X. The application allows to assess the quality of urban system objects and take into account the infrastructure, transport, consumer, location, mediaevents (photoregistration) and news recommendations (comments) of user activity, and draw users’ GPS tracks in accordance with the USCCTEI and ICD-10 with the classification of interobject relations. The possibility of integrating a mobile application with transport modeling and control systems is demonstrated. The practical guidelines for further use of mobile applications as part of intelligent transport systems are indicated.   10.18721/JCSTCS.11105 656, 007; 004.81, 614.8; 007; 51-7, 351; 351. intelligent transport systems mobile applications for transport transport correspondence matrices transport activity chains smart city transport behavior transport monitoring traffic classification https://infocom.spbstu.ru/article/2018.56.5/ 05.pdf

RAR RUS 65-74 Peter the Great St.Petersburg Polytechnic University Baydina Tatiana baydinatanya2401@gmail.com Peter the Great St.Petersburg Polytechnic University Burdakov Sergey control2@compmech.spbstu.ru Control of self-oscillations in contact interaction of a robot with a treated surface under nonlinear friction The article considers the problem of position-force control of the «robot – tool – detail» system movement, which is typical for machining operations. The tool is installed in elastic suspension, which provides force sensing of the robot. The robot, in accordance with the technological task, moves at a certain speed along the surface with a predetermined pressure to it. The non-linear nature of friction under elastic suspension of the tool and a small (creeping) speed of movement of the robot along the surface can cause frictional self-oscillations in the system. This can lead to a non-uniform motion with short-term stops of the tool. In this article, we have investigated the conditions under which this effect occurs by use of mathematical and computer simulation methods. Furthermore, it is shown how the frictional self-oscillations can be suppressed by another nonlinear effect, vibrational (pulse) smoothing. The way of making this process adaptive within the framework of a regular control system by use of a logical switching device is proposed. In the future it is planned to use artificial neural networks for these purposes. 10.18721/JCSTCS.11106 681.51 system «robot – tool – detail» force sensing position-force control contact interaction nonlinear friction Stribeck effect creeping speed self-oscillations pulse smoothing adaptation https://infocom.spbstu.ru/article/2018.56.6/ 06.pdf