Wyniki 1-2 spośród 2 dla zapytania: authorDesc:"Aigul SYZDYKPAYEVA"

Implementation of dual-frequency resonant vibratory machines with pulsed electromagnetic drive DOI:10.15199/48.2019.04.08

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At present, the systems with regulated modes using the control and feedback facilities are becoming more and more widespread. The implementation of such systems is very relevant problem for effective operation of vibratory machines with resonant modes. This is due to the influence of technological factors on the dynamics of their oscillatory system, in particular on its amplitude-frequency characteristic [1-4]. In order to balance this effect out, the amplitude and frequency control is used. It allows to eliminate structural inaccuracies (errors), to provide stable characteristics due to the effect of a changing load. The publications [4, 5] are devoted to solving this problem. In terms of introduction into practice, the resonant machines should be designed using an alternating current electromagnetic drive. This is due to the following factors: ─ high reliability and durability due to the lack of elements and pairs (couples) of mechanical friction; ─ simplicity of the machine starting up and stopping due to the absence of influence of the mechanical system on the drive dynamics, which is not typical for machines with an electromechanical drive using the effect of Sommerfeld [6]. Nevertheless, the vibratory resonant machines with single-frequency modes are of limited use [7]. The systems with two operation frequencies are much more effective [8- 10]. In addition to the technological advantages of dualfrequency resonant systems, it is also necessary to take into account higher dynamic stability in comparison with single-frequency systems [11]. The dual-frequency systems based on the combined ball-inertial vibrator may also be promising at the present time [8]. The proposed design allows to use the resonance mode at the same frequency due to the use of the Sommerfeld effect. However, such a vibrator has the disadvantages of the mode regulation since the changing of the harmonic amplitude value at this frequency [...]

A model of destructive processes based on interval fuzzy rough soft sets DOI:10.15199/48.2019.04.23

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Complex systems containing territories with natural and artificial objects as well as a multitude of interacting processes, which evolve in space and time, can be considered as geoecotechnogenic systems (GETS). Some processes arising within GETS are destructive because they give rise to a danger and risk to the certain valuable objects causing their destructions and can often lead to critical situations or emergencies. Solving decision support problems in disaster situation requires real-time geographic information systems (GIS) containing a spatial model of confined space (area of interest, AOI), where the destructive processes take place, as well as adequate models of the destructive processes exposed onto the spatial model. However, the most of the destructive processes are poorly observed and their spreading over the AOI is weakly modeled, so developing decision support systems (DSS) is a complex and nontrivial task, which becomes more complicated due to uncertainty of information, a wide geographically distribution of events and, as usual, a lack of time [1]. The efficiency of decision-making strongly depends on the availability of online disaster monitoring tools aimed at the real-time computation of the most important parameters related to the spreading of the destructive processes. Today, a suite of the most modern methods and techniques, such as remote sensing, GIS, geospatial analysis, unmanned aerial vehicles (UAV), can be synergistically used to build GIS-based DSS. Remote sensing techniques allow generating a full range of data for disaster monitoring [2], which have a form of streams of great volumes that come from sensors on a continuous basis at a high rate and should be analyzed in a real-time [3]. UAVs can effectively perform long-time missions to obtain remote sensing data [4]. However, due to the instrumental inaccuracy and distortions caused by vibrations, remote sensing information obtained from UAVs[...]

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