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In the paper, two integral strategies of active filtration in the reference frame of the two-wattmeters method are proposed, which are different from known ones by the simplicity of implementation, increased accuracy, and speed. The formula for calculating the energy-saving effect from active filtration in a three-phase three-wire power system in the conditions of unbalanced load and line voltages is derived. Experimental studies show that the proposed integral control strategy of active filtration with a reference vector of line asymmetric voltages provides the best energy-saving effect but generates asymmetric mains currents. The most promising is the proposed integral control strategy of active filtering with a reference vector of direct sequence line voltages, which provides almost the same energy-saving effect, symmetric sinusoidal currents of the network, and minimal ripple of power consumption.

Edge Computing (EC) is a paradigm introduced to support the end devices with the execution of computation intensive tasks while maintaining their intended Quality of Service (QoS). To achieve this, one or more Edge Servers (ES) with powerful capabilities are placed in a close proximity to the edge devices to provide the assistance needed. In order to do that, EC utilizes the concept of application offloading, which is the idea of moving the computation intensive tasks to be computed on a more powerful server. The act of offloading is not always a beneficial choice due to the aspect of availability of involved resources and data communication between devices. Therefore, to achieve a successful offloading process, the offloading decision making needs to answer the four questions of when, what, where and how to offload. In this paper, we investigate the “When to offload?” question, which is concerned with whether the offloading process results in a positive gain in performance or not. To strengthen our conclusions, we use empirical observations in a real setup running a set of emulated applications.

The main challenges of the first Internet of Things generation were related to communication latency due to high physical and logical distance between end devices and server resources, vulnerability for network problems along the long routes as well as power consumption management. Thanks to the unveiling of the latest wireless technologies like 4G and 5G, WiFi 5 and 6 as well as BLE, the last-mile connection performance - communication latency in particular - is taking a huge leap, and therefore introducing new possibilities for industrial applications. However, many open challenges remain. These include smart and efficient analysis of massive data, automated management of the full life cycle of IoT devices, etc. The newest developments in Artificial Intelligence, massive softwarization and virtualization, technologies beyond 5G and WiFi 6 give hope for the unveiling of new potentials. This talk uncovers the above dynamics.

The paper presents a design of a dual-polarized integrated lens antenna (ILA) dedicated to outdoor point-to-point systems operating in the 57–64 GHz frequency range. The ILA primary feed is based on a combination of a dual-polarized aperture coupled microstrip antenna (ACMA) patch and a low-profile metal adapter with a circular waveguide opening that corrects the patch radiation to provide effective illumination of the lens collimating surface and therefore high aperture efficiency of the antenna. A hemielliptical lens is made of high-density polyethylene (HDPE) and has a diameter of D = 120 mm needed to provide a high gain and cover large communication distance. Characteristics of the ILA were optimized using full-wave simulations and confirmed by the dedicated measurements of the fabricated antenna samples. Measurement results demonstrate that the designed dual-polarized ILA in the 57–64 GHz frequency range provides a gain value of 36–36.8 dBi with a reflection coefficient of > 10 dB and isolation between orthogonal linear polarizations exceeding 35 dB. In addition, the designed ILA has been integrated with a millimeter-wave monolithic microwave integrated circuit (MMIC) transceiver for operation in point-to-point systems with time-division duplexing (TDD).

The work is devoted to pilot modeling of the reaction of society to technogenic and biological sudden environmental influences. For the description, the methodology of the socio-technical landscape is used, which reflects the development of certain social practices in the digital and technical environments. At the bifurcation points of the evolution of the socio-technical landscape, the phenomena of the "Black Swan" and "Boomerang Blow" arise - a powerful impulse effect on the landscape. There is an urgent problem of predicting reaction reactions. The aim of the work is the development and pilot study of a self-organizing algorithm of structural-parametric identification of transients. Impacts of a technical and biological nature are considered as objects of research: the development of the use of artificial intelligence and computer technology in medicine and the spread of COVID 19. Models for countries: UK, Russia and Uzbekistan are given. It is shown that the reaction of the sociotechnical landscape is acceptable described by homogeneous differential equations of the second degree with a complex exponentially harmonic function on the right side. The most adequate mathematical models are given. This work was supported by the Russian Science Foundation grant # 19-18-00504.

Main goal is to enable better real time recommendations for trip support in time-location amplitude with social distancing reality in urban area. This paper describes main modern tendencies for the design and development of urban route planning recommender systems. In this research the difficulties and unsolved problems were analyzed for development and use of location-besed mobile recommender systems for social distancing. This paper focuses on project of development of mobile location-based recommender system with context evaluation.

The paper analyzes the analytical expression for active current of the electrical railway power system in the two-wattmeter method reference frame (TWMRF) to obtain the condition of unit power factor. Besides, as the main contribution of this paper, the optimal compensating strategy for railway power conditioner was proposed that suited for the random fluctuated two-phase loads to satisfy the power quality standard. The proposed control strategy differs from the based on instantaneous pq-theory one by absence of dual coordinate transformation which simplifies the construction of the control system, as well as increases its accuracy and speed. The correct functioning of the proposed strategy has been proven by the coincidence of theoretically substantiated and experimentally obtained dependencies of instantaneous active and reactive powers.

The paper presents the topology of a system of power generation connected to a grid based on two doubly-fed induction generators (DFIG) with selective current harmonic compensation capabilities. The scheme uses a grid-side converter supplying DC voltage with two rotor-side converters. A grid-side converter is linked to the network as well as each of the rotor-side converters are associated to the respective generator rotor. DFIG's basic control algorithm aims primarily to obtain maximum power output of wind at variable wind speeds. The possibility of improving the electric energy quality within the power of the converter is realized by compensating the grid current harmonics. The control purpose of the rotor-side converter is to generate a maximum of active power and improve quality of power. The harmonic components of the current are distributed for compensation by two generators separately. To demonstrate the usefulness of the scheme the whole generation system is simulated. The results of simulation are presented.

The paper describes a wideband dual-polarized MIMO antenna designed for 5 GHz Wi-Fi communication networks. The antenna consists of two orthogonally linearly polarized 4x4 planar arrays with dipole-like radiating elements providing enhanced bandwidth. Apertures of the two arrays are overlapped by disposal of the corresponding PCBs one above the other that makes the MIMO antenna as compact as a single-polarized one. The antenna is integrated into a water-proofed enclosure with a plastic radome and has two output N-type connectors. Measurement results confirm good impedance matching (reflection coefficient is less than -10 dB) and high cross-polarization isolation of more than 23 dB in the 4.9-6.0 GHz frequency range with 17.5-18.5 dBi gain level. The beamwidth of the antenna is 17-20 deg. in both azimuth and elevation planes. High antenna gain provides increased communication distance (up to several kilometers) of the radios typically needed for any outdoor fixed wireless access applications while the antenna has been primarily developed for trackside communication networks in subways. Thus, it is already used in Moscow metro to provide high-throughput Internet access to passengers.

The problem of long-range space communications systems with high-capacity channels is topical due to a series of deep space projects being currently implemented, such as international missions Exo-Mars and Millimetron. To maximize the rate of the data transfer in space communications systems, antennas with maximum available dimensions are used to provide reasonable capacity. We are offering an approach to increase the capacity of data transfer channels by use of a combination of a large antenna and wide-bandwidth, high-capacity, low-noise, high-frequency cryogenic receivers. When the communication is performed in the millimeter waveband the atmospheric propagation becomes the essential limiting factor to the use of the channel. The theoretical estimations of capacity limits under different atmospheric conditions for diverse hardware and the results of experiments are presented.