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Pulsating mode of asynchronous motors operation is finding wide application in various electric drives. In this regard, the problem of creating mathematical models of a pulsating mode, taking into account the real factors, becomes urgent. These models will allow to optimize the process of designing of the pulsing actuators based on asynchronous motors. The article describes mathematical models of...
In this paper we overview the modern forecast methods of monthly sunspot numbers, such as McNish-Lincoln and Hathaway-Wilson-Reichmann standard curve-fitting. Their disadvantages are presented, leading us to the necessity of researching a new technique for the solar activity prediction. For the long-term forecast we propose to use the established nonlinear dynamo model based on negative effective...
The mathematical model of an acoustic field formed in an acoustic chamber with a noise-protective baffle is proposed. According to the experimental data, an analytic function that approximates the signal power spectrum at the receiving point is found. The parameters of the function that provide the best approximation for the given geometric dimensions of the resonator and the source signal frequency...
The paper deals with the estimation method of a carrier and time of arrival by chirp-like phase-coded sequence. The developed estimation method of the carrier and time of arrival is suitable for primary synchronization upon signal detection in phase and frequency modulation modems. This method is of less computational complexity relative to the realization of matched filter assembly. To implement...
The article compares the centrifugal pumping units electric drive dynamic characteristics at different rotational speeds of the main magnetic field. The tooth harmonics order is determined by the number of stator slots, which depends on the main magnetic field rotation frequency. Proposed mathematical model takes into account the tooth harmonics of the electric motor and the hydraulic parameters of...
This article presents simulation results for a mobile ad-hoc network running Dynamic Source Routing reactive protocol under the conditions of limited availability and heightened response times of network nodes. Authors conclude that dynamic source routing stops being efficient in large networks and propose a hybrid routing protocol that includes the proactive phase and uses availability criterion...
Static biometrie images are not private and may be copied to make a physical and digital stimulant without an owner being aware of it, therefore the search for efficient solutions of personal authentication via dynamic biometric characteristics is still in process. A series of computational experiments based on biometric data obtained through a handwritten signature and keystroke dynamics is carried...
We present Geographic Information System model, which is developed on the basis of metasystem approach and it is focused on application as monitoring system of complex object. The model is described on the basis of set-theoretic approach, functions according to scenarios, integrates, processes and monitors the space-time and coordinate information. The problem of acquisition and reversible compression...
The paper deals with the issues of measurement traceability based on uncertainty of measurements as an integral part of specific measurement technologies based of new information system. A short review of papers devoted to measurement traceability problem in modern conditions is described. It is proposed to further expand a concept of "special technical means" in carrying out of measurements...
Synchronous-in-phase electric drives are widely used in thermal-imaging and laser scanning systems due to high accuracy characteristics in a wide range of angular velocity control. The purpose of the article is to investigate the method of controlling an electric drive with phase synchronization under the reference signal jumps. The results of computer simulation modelling of the synchronous-in-phase...
Linear-quadratic problem for a time-invariant scalar continuous time system and a bound spectrum disturbance is considered. The problem is shown to be degenerate; and an algorithm of the regulator synthesis is presented.
In the paper, the hybrid model of electronic design document in the form of combining set-theoretical, graph-theoretical models and automata theory using mathematical apparatus of domain specific ontologies, which include models of structure and dynamics of life cycle of electronic design document is offered. The model considered in this paper can be applied in the process of creating the integrated...
The comparative analysis of the efficiency of processing of signals information parameters by the discriminators of tracking meters when exposed non-Gaussian broadband and band-limited noise is carried out. It is shown that when band-limited noise influences the discriminator, the efficiency of non-linear processing is higher and it the band-limited path and it increases with the increase of the signal/noise...
The relevance of the present study devoted to the development of a modern microcontroller measuring control system for linear displacements based on fiber optic and optoelectronic elements is shown. This is necessary for Russia to strengthen its defenses and create competitive technologies in the industrial sphere. The goal of the work was formulated as the implementation of structural synthesis and...
The quasi-likelihood algorithm detection of rectangle ultra-wideband quasi-radiosignal with unknown amplitude, initial phase and duration has been synthesized. The statistical characteristics of the efficiency synthesized detection algorithm — false alarm probability and probability of missing a signal, have been found.
This article presents the results of the magneto-electric machine's research of the wind energy conversion systems' (WECS) alternating current. Calculation of the researched machine was carried out with the latest version of the programs "Elcut 6.2 Professional" complex using. The operation's purpose was creation of the researched object's adequate geometric model, obtaining the machine's...
The article describes the hardware architecture of computational units for the construction of GLONASS / GPS navigation user equipment. The described possible route to improve of some architectures based on field programmable gate arrays (FPGAs).
A device for the detection of polymers is under the development. The use of ultrasonic waves for understanding the aquatic environment is undertaken in this work. The material presented explains how the waves behave for different samples (size, shape, composition) of polymers and the observation is the signature of the species under study.
This paper describes the experimental study of a synchronous magnetoelectric generator which magnetic system is based on the asynchronous motor: the stator of magnetoelectric generator is made up of induction machine with a number of poles pairs 2p=12, a cylindrical inductor (rotor) is composed of permanent magnets distributed on the rotor surface. The modeling of magnetic system was carried out using...
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