Telfor Journal Vol.16 No.2 (2024)

Content

A. V. Gevorkyan

Topic:: Applied Electromagnetics
Abstract: In this paper presents the design and radiation characteristics of a stepped printed dipole antenna array element. The array element is designed to operate in the 5G millimeter wavelength (mm-Wave) range (from 24.25 to 27.50 GHz). In the required frequency band, the value of the VSWR does not exceed 1.30. The value of the realized gain ranges from 4.53 to 5.59 dB. The overall dimensions (width × depth × height) are 6 mm × 6 mm × 2 mm. Based on it, a model of a 4 ×4 antenna array was developed. Its radiation characteristics were compared with the characteristics of the arrays of the differently shaped dipole antennas (a horizontal flat, a horizontal flat with matching inserts, a vertical flat, and a volumetric). It is shown that the stepped shape of the dipole makes it possible to obtain the best characteristics.
Keywords: 5G communications, antennas, broadband antennas, dipole antennas, microwave antennas, millimeter waves.
Full Text: Stepped Printed Dipole Antenna Array Element
Page(s): 20-25
Doi: 10.5937/telfor2302020G

E. D. Chueva, E. A. Demin, E. A. Fedorova, and E. G. Baranova

Topic:: AI
Abstract: The main goal of the study is to determine whether artificial intelligence can create mathematical and simulation models of the automatic room heating system, and therefore test the abilities of artificial intelligence in the field of engineering sciences. The scientific novelty of the article is the development of a simulation model of an automatic room heating system with relay temperature control using artificial intelligence. To fully and comprehensively disclose the purpose of the study, elementary physical laws are provided that describe the processes of heat transfer and thermal conductivity of the air in a confined space, such as Joule-Lenz's law or Ohm's law and describe the foundations of the theory of automatic control, and in particular the role of necessary links and negative feedback. Based on the operation of the built models, graphs of the resulting temperature are given, on the basis of which the operating time, the maximum achieved temperatures and the switching time of the heater are based.
Keywords: automatic room heating system; artificial intelligence; energy efficiency; data analysis; modelling.
Full Text: Comparative Analysis of Efficiency of Automatic Heating Systems Developed with the Help of Artificial Intelligence and Human
Page(s): 26-31
Doi: 10.5937/telfor2302026C

I. Vujović, M. Koprivica, and Ž. Đurišić

Topic:: Telecommunications Networks
Abstract: Different types and different size photovoltaic (PV) systems are in use. Assuming that these systems are equipped with some of the: internet of things (IoT) devices, intelligent electronic devices (IED), phasor measurement units (PMUs) and that they are properly communicate with control center, or that inverters in the PV systems contain network interface cards (NIC-s) which are connected to the control center through network, a solution for infrastructure of the monitoring and management (M&M) system is proposed. The main parts of the system are cloud infrastructure on which supervisory control and data acquisition (SCADA) system is implemented, network that connects all parts of cloud together and enables connections, through proprietary links or service providers networks, to the distributed devices as well as to the inverters at PV sites. Time synchronization between the central part of the SCADA system and devices at PV systems sites enables obtaining precise moments of the events occurrence and timely response. All parts of the SCADA system and network must be secured from the inside and outside threats.
Keywords: PV system, SCADA, network, time synchronization, security.
Full Text: Implementation of the SCADA based Infrastructure for Distributed PV Systems Controlling
Page(s): 32-37
Doi: 10.5937/telfor2302032V