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Conférence virtuelle; International audience; A new pattern reconfigurable 2×2 array antenna is proposed. The antenna has two modes of operation, Array Mode and Multiple-Input-Multiple-Output (MIMO) Mode. The single element antenna used is a pattern reconfigurable U-slot antenna with four pattern configurations. An average efficiency of 80%, a peak gain of 9.4 dB, and an overlapped −10 dB impedance bandwidth of 200 MHz around the resonant frequency 3.65 GHzare achieved. The size of the proposed antenna is 140×140×21 mm3 , which is suitable for small cell base-stations. For the MIMO Mode, the antenna has a maximum ECC of 0.06 between the four patterns and a minimum isolation of 12.9 dB between the four ports. For the array Mode, the antenna has a peak gain of 12.5 dB, and steering angles for 0 ◦ ≤ θ ≤ 30◦ in the planes at φ = 0◦ and φ = 90◦ Pattern reconfigurability is achieved using electrical switching. The used substrate is FR-4 with a dielectric constant of Epsilon_r = 4.4, and a loss tangent of tan δ = 0.02.

An electromagnetic field penetrating through an aperture or slot of a metallic enclosure generates many standing-waves due to the resonance inside the metallic enclosure, which results in reduced shielding performance. This paper examines the effect of absorbent material (absorber) to improve shielding effectiveness (SE) of large metallic rooms with apertures or slots. First, a theoretical formulation to extract the Q-factor of an absorber with any shape is proposed. Using this, the contribution of the absorber to the SE improvement of a shielded room with different sized circular apertures was investigated. Second, the resonant mode density inside the shielded room was classified into non-resonant, under-moded, and over-moded states with an increase in frequency, and the effect of the absorber in each frequency range was examined. The analysis was conducted through numerical simulation using a commercial full-wave simulator and experimental measurement using a fabricated actual shielded room and commercial absorbers. The accuracy of the analysis results was verified through the comparison of simulated and measured results. The analysis results ensured that the absorber was not effective in improving the SE in the non-resonant state of the metallic room. It was also confirmed that the absorber was effective in improving the SE in the over-moded state of the metallic room where a severe standing-wave occurs. In addition, the SE improvement level differed depending on the location of the absorber in the room.

We present a system that displays an image of any metal structure in a scene by the use of microwave radiation from a cavity resonator in a 10-GHz frequency band. An 80 mm x 80 mm mushroom-like electromagnetic band gap (EBG) structure was arranged, designed, analyzed, and integrated with an X band monopole antenna and the designed EBG monopole antenna has similar to 2-GHz bandwidth. Meanwhile, a cubic cavity resonator is constructed and an EBG grounded monopole antenna is located on one wall of the cavity resonator to create a narrow band radiation. The formed narrow band radiation from the cavity resonator reaches to the metal structure located in the scene. Backscattered radiation collected by a 8 to 12 GHz waveguide receiver that is located near the cavity to scan the whole scene and sweep the waveguide throughout the resonator plane performs to gather various transmission values from a scene. These various transmissions from the cavity resonator antenna to the waveguide receiver were used for imaging. In addition, tunability of the designed EBG structure is studied and presented. The designed structure has advantages such as easy design and fabrication, high accuracy performance, and compatibility to the other frequency regimes. In addition, the designed EBG plane is based on RLC circuit theory, which enables us to understand the antenna performance and EBG structure. This system can be integrated with various areas, such as medical imaging, military applications, weapon detections, security imaging purposes, stealth technology, and other appropriate applications.

В статье представлен практический аспект неологизации лексической системы русского языка. На основе сплошной выборки из различных источников средств массовой информации проведен анализ неологизмов, вошедших в лексическую систему русского языка, но не всегда фиксируемых словарями. Дана характеристика неофразем и их классификация по фреймам и слотам. Подробно рассмотрены языки сферы менеджмента, IT-технологий и других социокультурных сфер, формирующих свои терминологические поля; представлены некоторые неологизмы, вошедшие в язык из новейшей сферы исследования, касающейся COVID-19. Еще раз подчеркивается гибкость лексической системы русского языка, не только привлекающую новые слова и фразы, но и активно трансформирующую их., The article presents a practical aspect of the neologization of the Russian lexical system. On the basis of a continuous sample from various sources of the mass media, an analysis of neologisms included in the lexical system of the Russian language, but not always recorded by dictionaries, is carried out. The characteristics of neophrasemes and their classification by frames and slots are given. The languages of the sphere of management, IT-technologies and other socio-cultural spheres that form their own terminological fields are considered in detail; there presented some of the neologisms that have entered the language from the latest research area regarding COVID-19. The flexibility of the lexical system of the Russian language which not only attracts new words and phrases but also actively transforms them, is emphasized once again.

Данная работа посвящена исследованию возможности создания волноводного ответвляющего фазовращателя для фазированной антенной решётки с последовательным питанием. В Ñ Ð¾Ð´Ðµ данной работы была построена модель волноводного ответвляющего фазовращателя в программе HFSS ANSYS. Возможности данной программы позволяют произвести моделирование фазовращателя с заданными параметрами Ð²Ñ Ð¾Ð´Ð½Ð¾Ð³Ð¾ сигнала, материала устройства, Ð³Ñ€Ð°Ð½Ð¸Ñ‡Ð½Ñ‹Ñ ÑƒÑÐ»Ð¾Ð²Ð¸Ð¹. В процессе моделирования производилось изменение размеров, положения и диэлектрической проницаемости щели. При изменении диэлектрической проницаемости менялся максимум частоты Ð²Ñ‹Ñ Ð¾Ð´Ð½Ð¾Ð³Ð¾ сигнала, в связи с чем производилось изменение длины щели для ÑÐ¾Ñ Ñ€Ð°Ð½ÐµÐ½Ð¸Ñ максимума в одном значении в начальном положение щели. После подбора начального положения щели при данной диэлектрической проницаемости, производилось смещение щели относительно начального положения на ±5 мм с шагом 1 мм. В результате каждого смещения производился анализ полученной модели и строился график S_31 параметра Ð²Ñ‹Ñ Ð¾Ð´Ð½Ð¾Ð³Ð¾ сигнала от частоты. В результате данной работы был зафиксирован сдвиг фаз Ð²Ñ‹Ñ Ð¾Ð´Ð½Ð¾Ð³Ð¾ сигнала относительно положения щели. Найдена практическая и теоретическая зависимость размера щели от её диэлектрической проницаемости. Волноводный фазовращатель используется в ÑÐ²ÐµÑ€Ñ Ð²Ñ‹ÑÐ¾ÐºÐ¾Ñ‡Ð°ÑÑ‚Ð¾Ñ‚Ð½Ð¾Ð¹ Ñ‚ÐµÑ Ð½Ð¸ÐºÐµ, в частости в ÑÐ¸ÑÑ‚ÐµÐ¼Ð°Ñ Ñ большим числом потребителей – для создания Ð½ÐµÐ¾Ð±Ñ Ð¾Ð´Ð¸Ð¼Ð¾Ð³Ð¾ распределения Ð½Ð°Ñ‡Ð°Ð»ÑŒÐ½Ñ‹Ñ Ñ„Ð°Ð· Ð¿Ð¾ÑÑ‚ÑƒÐ¿Ð°ÑŽÑ‰Ð¸Ñ Ðº ним сигналов. Так же используется в Ñ„Ð°Ð·Ð¸Ñ€Ð¾Ð²Ð°Ð½Ð½Ñ‹Ñ Ð°Ð½Ñ‚ÐµÐ½Ð½Ñ‹Ñ Ñ€ÐµÑˆÑ‘Ñ‚ÐºÐ°Ñ Ð¸ Ð´Ñ€ÑƒÐ³Ð¸Ñ ÐºÐ¾Ð³ÐµÑ€ÐµÐ½Ñ‚Ð½Ñ‹Ñ Ñ€Ð°Ð´Ð¸Ð¾ÑÐ¸ÑÑ‚ÐµÐ¼Ð°Ñ ., This work is devoted to the study of the possibility of creating a waveguide branching phase shifter for a phased array antenna with series power supply. In the course of this work, a model of a waveguide branching phase shifter was constructed in the HFSS ANSYS program. The capabilities of this program allow you to simulate the phase shifter with the given parameters of the input signal, device material, boundary conditions. During the simulation, the dimensions, position and dielectric constant of the slit were changed. With a change in the dielectric constant, the maximum of the output signal frequency changed, in connection with which the slit length was changed to maintain the maximum at one value at the initial position of the slit. After selecting the initial position of the slit for a given dielectric constant, the slit was displaced relative to the initial position by ± 5 mm with a step of 1 mm. As a result of each offset, the resulting model was analyzed and a graph of the S_31 parameter of the output signal versus frequency was plotted. As a result of this work, the phase shift of the output signal relative to the position of the slot was recorded. A practical and theoretical dependence of the gap size on its dielectric constant has been found. A waveguide phase shifter is used in microwave technology, in particular in systems with a large number of consumers - to create the necessary distribution of the initial phases of the signals coming to them. Also used in phased array antennas and other coherent radio systems.

In this study, a dual-port wind-energy conversion system has been proposed. A double-fed permanent-magnet synchronous generator (DFPMSG) forms the central part of the system, where the concentrated single-layer winding configuration of the generator enables electric and magnetic isolation between the ports. DFPMSG has two three-phase terminals out of the stator; one is connected directly to the grid, whereas the other is tied to the grid through a back-to-back converter. This study investigates design issues caused by the DFPMSG port with a direct grid connection. The unique design issues of the proposed system include determining the slot/pole combination using wind data and determining the minimum reactive power requirement for the port with a direct grid connection. Next, the load-sharing capability among the ports of the proposed system is presented through a detailed investigation of three schemes. Experimental work is presented for a 5-kW prototype DFPMSG system to illustrate the isolation among the ports, minimized reactive power demand on the port with direct grid connection, and load-sharing ability among the ports for different control schemes., Scientic and Technological Research Council of Turkey [117E785], This work was supported by the Scientic and Technological Research Council of Turkey under Contract 117E785.

Был проведен анализ Ð½Ð°Ñ Ð¾Ð´ÑÑ‰Ð¸Ñ ÑÑ в общем доступе Ð´Ð°Ð½Ð½Ñ‹Ñ Ð½Ð° тему Ñ Ð°Ñ€Ð°ÐºÑ‚ÐµÑ€Ð¸ÑÑ‚Ð¸Ðº материалов упругого пазового уплотнения стержней обмотки статора генератора. Рассмотрены основные проблемы в изоляции статоров такие, как вибрационное искрение и пазовые разряды. Были сделаны выводы о Ð½ÐµÐ¾Ð±Ñ Ð¾Ð´Ð¸Ð¼Ð¾ÑÑ‚Ð¸ разработки методики определения Ñ Ð°Ñ€Ð°ÐºÑ‚ÐµÑ€Ð¸ÑÑ‚Ð¸ÐºÐ¸ Ð²Ð¾Ð»Ð½Ð¾Ð¾Ð±Ñ€Ð°Ð·Ð½Ñ‹Ñ ÑÑ‚ÐµÐºÐ»Ð¾Ñ‚ÐµÐºÑÑ‚Ð¾Ð»Ð¸Ñ‚Ð¾Ð²Ñ‹Ñ Ð¿Ñ€Ð¾ÐºÐ»Ð°Ð´Ð¾Ðº к изгибающим нагрузкам. Разработана методика, по которой проводились дальнейшие испытания. В Ð»Ð°Ð±Ð¾Ñ€Ð°Ñ‚Ð¾Ñ€Ð½Ñ‹Ñ ÑƒÑÐ»Ð¾Ð²Ð¸ÑÑ Ñ помощью разрывной машины MARK-10 были проведены исследования адгезионной прочности при статическом изгибе Ð²Ð¾Ð»Ð½Ð¾Ð¾Ð±Ñ€Ð°Ð·Ð½Ñ‹Ñ ÑÐ»ÐµÐºÑ‚Ñ€Ð¾Ð¸Ð·Ð¾Ð»ÑÑ†Ð¸Ð¾Ð½Ð½Ñ‹Ñ Ð¸ Ð¿Ñ€Ð¾Ð²Ð¾Ð´ÑÑ‰Ð¸Ñ Ð¿Ñ€Ð¾ÐºÐ»Ð°Ð´Ð¾Ðº для уплотнения обмотки статора Ð²Ñ‹ÑÐ¾ÐºÐ¾Ð²Ð¾Ð»ÑŒÑ‚Ð½Ñ‹Ñ Ð³ÐµÐ½ÐµÑ€Ð°Ñ‚Ð¾Ñ€Ð¾Ð². Получены и проанализированы данные, результаты представлены в виде Ð³Ñ€Ð°Ñ„Ð¸Ñ‡ÐµÑÐºÐ¸Ñ Ð¸Ð·Ð¾Ð±Ñ€Ð°Ð¶ÐµÐ½Ð¸Ð¹, а также ÑÑ€Ð°Ð²Ð½Ð¸Ñ‚ÐµÐ»ÑŒÐ½Ñ‹Ñ Ñ‚Ð°Ð±Ð»Ð¸Ñ†., The analysis of publicly available data on the characteristics of the materials of the elastic grooved seal of the generator stator coil rods was carried out. The main problems in the isolation of stators, such as vibration sparking and grooving discharges, are considered. Conclusions were drawn about the need to develop a methodology for determining the characteristics of wave-shaped glass-fiber gaskets to bending loads. A methodology was developed for further testing. Under laboratory conditions, the MARK-10 bursting machine was used to study the adhesive strength under static bending of wave-like electrical insulation and conductive gaskets for sealing the stator winding of high-voltage generators. The data were obtained and analyzed, the results are presented in the form of graphical images, as well as comparative tables.

This article describes the experience of modeling the frame of the e-learning terminology system. The theory of frames is analyzed to build this model, and the method of frame analysis of e-learning terminology is applied. Frame-based modeling is a way of interacting and gaining knowledge about an entity, while situational conceptualization involves understanding how entities interact with each other. The terminological system of e-learning is investigated from the point of view of the semantics of frames, since a frame is a semantic structure in which the bulk and content of the cognitive structure is concentrated in the process of its verbalization. Thus, the purpose of this study is to build a frame model for the e-learning terminology system. To achieve this goal, a number of objectives are realized in this research: identifying the basic concepts that underlie the terminology system of electronic education, categorizing terms according to the identified basic principles and constructing a frame scheme for the entire studied professional sphere. We believe that the considered frame modeling of the e-learning terminological system is an effective tool for systematize the terminological system and a way of presenting professional knowledge of the studied area for the following reasons. Frames, taken as representations of stereotyped knowledge in a filled-slot format, can act as definition models, offering more consistent and flexible representations of conceptual structure. The definitions of the terms can be considered as representations of the minimum knowledge that serve as an outline for each category. Definitions, as a template for conceptual content, activate broader conceptual frameworks in the form of frames that reveal the prototypical structure of the conceptual description of an object., Данная статья посвящена описанию опыта моделирования фрейма терминологической системы электронного обучения. Для построения данной модели анализируется теория фреймов и применяется метод фреймового анализа терминологии электронного обучения. Фреймовое моделирование представляет собой способ взаимодействия и получения знаний о сущности, а ситуативная концептуализация включает представление о том, как сущности взаимодействуют друг с другом. Терминологическая система электронного обучения исследуется с точки зрения семантики фреймов, так как фрейм это семантическая структура, в которой основной объем и содержание когнитивной структуры концентрируется в процессе ее вербализации. Таким образом, цель данного исследования заключается в построении фреймовой модели терминосистемы электронного обучения. Для реализации поставленной цели в данной работе решается ряд задач: выявление базовых концептов, лежащих в основе терминосистемы электронного образования, категоризация терминов согласно выявленным базовым принципам и построение фреймовой схемы всей изучаемой профессиональной сферы. Полагаем, что рассматриваемое фреймовое моделирование терминологической системы электронного обучения является эффективным инструментом упорядочивания терминологической системы и способом представления профессиональных знаний изучаемой области по следующим причинам. Фреймы, взятые как представления стереотипных знаний в формате заполненных слотов, могут действовать как модели определений, предлагая более последовательные и гибкие представления концептуальной структуры. Определения терминов можно рассматривать как представления минимальных знаний, которые являются контуром для каждой категории. Определения, как шаблон концептуального содержания, активируют более широкие концептуальные структуры в форме фреймов, которые раскрывают прототипную структуру концептуального описания объекта.

El alcance de las nuevas tecnologías en telecomunicaciones ha traído consigo nuevos retos para la industria como la implementación, diseño y construcción de nuevas antenas. La quinta generación de las tecnologías de telefonía móvil (5G), está fundamentada en sistemas basados en ondas milimétricas, por lo que este proyecto tiene como objetivo diseñar y simular una antena de ranuras no resonante basada en guías de onda metálicas rectangulares para operar en el rango de los 60 GHz, con gran ancho de banda. Se obtiene el diseño de la antena a través de la implementación de una herramienta en Matlab, empleando la síntesis Chebyshev con el fin de determinar la distribución de corriente de cada elemento del array. Con base en esta información, se obtienen su diagrama de radiación teórico y las dimensiones físicas de la antena, las cuales se simulan con el software CST Microwave Studio, obteniendo su diagrama de radiación y las pérdidas de retorno, que, al compararlas con el diagrama de radiación teórico, se observan resultados satisfactorios, que permiten validar la herramienta implementada. En este proyecto se ha descrito el diseño de un array de ranuras lineales, no resonante, el cual fue validado con el software CST Microwave Studio. Se desarrolló una herramienta implementada en Matlab, para el diseño de antenas de ranuras lineales no resonantes en guía de ondas, con resultados satisfactorios, teniendo en cuenta que, a la frecuencia de diseño, que fue de 60 GHz, las mínimas variaciones en las dimensiones de la antena, cambian significativamente sus parámetros. Se encontró que el criterio de diseño de Chebychev es apropiado cuando se requieren arrays directivos y lóbulos secundarios decrecientes. Se verificó que las antenas de ranuras no resonantes presentan un gran ancho de banda. The scope of new technologies in telecommunications has brought with it new challenges for the industry such as the implementation, design and construction of new antennas.The fifth generation of mobile telephone technologies (5G), is based on systems based on millimeter waves, so this project aims to design and simulate a non-resonant slot antenna based on rectangular metal waveguides to operate in the 60 GHz range, with high bandwidth. The design of the antenna is obtained through the implementation of a tool in Matlab, using the Chebyshev synthesis in order to determine the current distribution of each element of the array. Based on this information, its theoretical radiation diagram and the physical dimensions of the antenna are obtained, which are simulated with the CST Microwave Studio software, obtaining its radiation diagram and return losses, which, when compared with the diagram of theoretical radiation, satisfactory results are observed, which allow to validate the implemented tool. In this project, the design of a non-resonant linear slot array has been described, which was validated with the CST Microwave Studio software. A tool implemented in Matlab was developed for the design of non-resonant linear slot antennas in waveguides, with satisfactory results, given at the design frequency, which was 60 GHz, the minimum variations in dimensions antenna, significantly change its parameters. The Chebychev design criterion was found to be appropriate when directing arrays and decreasing secondary lobes are required. Non-resonant slot antennas were verified to have a high bandwidth.