scholarly journals Adjustable circuits on semiconductor switching elements as a matching device in radar stations for outer space monitoring

2020 ◽  
Vol 30 (4) ◽  
pp. 79-86
Author(s):  
S. V. Kulikov ◽  
S. Yu. Ashchunin ◽  
V. O. Korolev ◽  
V. N. Aldokhina
Keyword(s):  
Antenna Arrays ◽  
Mutual Influence ◽  
Outer Space ◽  
Input Resistance ◽  
Load Resistance ◽  
Practical Significance ◽  
Phased Array Antenna ◽  
Complex Load ◽  
Detection Range

Formulation of the problem. When scanning in space by a phased array antenna (PAA), which consists of a large number of emitters, there is an interaction between them in the form of impedance. It affects the matching quality of the receiving-transmitting module of the PAA with the emitter and leads to significant losses of power and detection range of the radar station.Objective. Improving the quality of the PAA emitters matching when changing the position of the antenna directional pattern beam in space due to the use of adjustable super high frequency (SHF) matching circuits on the switching elements.Results. The article substantiates an increase in the functional capabilities of the development of adjustable matching circuits of super-high frequencies due to the use of switching elements in the device, which allow reducing the influence of factors caused by a change in the input impedance of the radiating element in phased antenna arrays. Based on the presented mathematical model, the change in the input resistance of the radiating elements is taken into account, which arises due to their mutual influence, and makes it possible to research the potential characteristics of controlled circuits when their structure and parameters change. The method of choosing the structure and parameters allows the device to be adjusted to the change in the input complex load resistance and ensure the minimum voltage standing-wave ratio.Practical significance. The proposed device allows for the calculation of implemented adjustable matching circuits, which, with existing materials and manufacturing technologies, provide a decrease in losses and an increase in range. An experimental model of microstrip design was developed based on the proposed device and a field experiment was carried out, which confirmed the correctness of the approach to the developed device.

scholarly journals IRRADIATOR WITH MINIMAL LOSSES OF PARABOLIC ANTENNA FOR RADIO MONITORING SYSTEMS OF INFORMATION CHANNELS OF RADIO RELAY COMMUNICATION LINES

2021 ◽  
pp. 24-30
Author(s):  
N. M. Karaschuk ◽  
I. A. Tsikalov ◽  
V. O. Savenko
Keyword(s):  
Circular Waveguide ◽  
Input Resistance ◽  
Outer Radius ◽  
Practical Significance ◽  
Detection Range ◽  
Radio Monitoring ◽  
Parabolic Antenna ◽  
Relay Communication ◽  
Communication Lines ◽  
Conical Horn

Analysis of the experience of modern struggle shows that the success of combat missions to sone extent depends on the timely detection of information from communication channels, in particular, radio relay communication lines. Increasing the detection range of the radio monitoring station can be achieved by using a mirror parabolic antenna with a radiation in the form of a conical horn with low losses due to the use of a matching device. The constructive decisions of matching devices are analysed and it is determined that most of them are resonant. The substantiation and selection of the design of the dielectric transformer with the length ( – wavelength in a round waveguide, m) for coordination of the conical horn irradiator in the whole band of its operating frequencies for the wave type is carried out. To achieve the goal, the methods of antenna theories and electrodynamics were used, in particular the theory of long lines. A mathematical apparatus has been developed for calculating the parameters of a dielectric transformer (the length ). It is stated that its impedance must be equal to the modulus of load resistance. The calculation of the value of the active transformed resistance according to the formula (10) always gives a positive value of the input resistance, the value of which is greater the greater the reactive load reactance. The reliability of the obtained formulas is confirmed by the convergence of units and graphs of dependences of the changes of the outer radius of the coaxial power line (its impedance), as well as the thickness and place of inclusion on the matching dielectric transformer . The practical significance of the research results lies in the possibility of improving the matching of a horn antenna based on a circular waveguide in the range of its operating frequencies for a certain type of wave.

Influence of the Aperture Edge Diffraction Effects on the Mutual Coupling Compensation Technique in Small Planar Antenna Arrays

2011 ◽  
Vol 57 (1) ◽  
pp. 115-120 ◽  
Author(s):  
Mariusz Zamłyński ◽  
Piotr Słobodzian
Keyword(s):  
Antenna Arrays ◽  
Mutual Coupling ◽  
Planar Antenna ◽  
Sidelobe Level ◽  
Edge Diffraction ◽  
Narrow Angle ◽  
Compensation Technique ◽  
Diffraction Effects ◽  
Linear Antenna Arrays

Influence of the Aperture Edge Diffraction Effects on the Mutual Coupling Compensation Technique in Small Planar Antenna Arrays In this paper the quality of a technique to compensate for mutual coupling (and other phenomena) in small linear antenna arrays is investigated. The technique consists in calculation of a coupling matrix, which is than used to determine corrected antenna array excitation coefficients. Although the technique is known for more than 20 years, there is still very little information about how different phenomena existing in a real antenna arrays influence its performance. In this paper two models of antenna arrays are used. In the first model the effect of mutual coupling is separated from the aperture edge diffraction. In the second model antenna both mutual coupling and aperture edge diffraction effects are included. It is shown that mutual coupling itself can be compensated very well and an ultralow sidelobe level (i.e. -50 dB) could be achieved in practice. In the presence of diffraction effects -46.3 dB sidelobe level has been attained, but radiation pattern can be controled only in narrow angle range (i.e. up to ±60°).

SPECIFIC FEATURES OF ALTERNATIVE COMMUNICATION WITH CHILDREN WITH SENSORY DISORDERS AND MULTIPLE DISABILITIES

2018 ◽  
Vol 28 (3) ◽  
pp. 1027-1030
Author(s):  
Gergana Todorova - Markova
Keyword(s):  
Sign Language ◽  
Mutual Influence ◽  
Multiple Disabilities ◽  
Educational Needs ◽  
Special Focus ◽  
Special Educational Needs ◽  
Alternative Communication ◽  
Sensory Disorders ◽  
Communication Situations

The article is focused on the communication with children with special educational needs. The main topic is alternative communication with children with sensory disorders and multiple disabilities. It explores the phenomenon of communication, citing current definitions developed by a number of authors, which place the emphasis on different aspects of this complex and multilayered process, with a special focus on alternative communication with the groups of special needs children mentioned in the title.The issue is investigated from a special pedagogical and from a social perspective.The author is especially interested in the exploration of the multiple strata of communication (the universal, functional and specific levels). Apart from the different forms, contents, methods and means of communication (the last of which is most commonly discussed in Bulgaria), the article is focused primarily on the important methodological issues related to this topic.One of these basic questions of methodology is the attempt not to place at the center of this process its bi-directional nature, its algorithm or code (sign language, Braille writing system, etc.), but instead to focus on the personalities of those involved in the interaction, their initiative, relationship and goals manifested in different communication situations (mutual influence, emancipation and therapy). Particular emphasis is given to therapy, i.e. the way of influencing the communication behavior of children with sensory disorders and multiple disabilities. It is not viewed as a unilateral process (stimulus-response), but as an interactive one, based on mutual influence. The relationship between the communicators is of utmost significance.Communication is characterized by a number of specific features. Those can mostly be found in the specificity of the communication situations (for example the interactive situations in the following pairs of communicators: deaf – hard of hearing; deaf – deaf; deaf-blind – deaf, etc.), in the presence of an intermediary (for example a sign language interpreter) and above all in the personalities of the communicators. They change the quality of communication. It is for this reason, and not just because of the different means of communication, that this interaction is defined as “alternative”, or more precisely, it is an alternative to the communication of children without disabilities.Based on the analyzed information, the author formulates a number of inferences and recommendations. The main conclusion is the following:When discussing alternative communication with children with special educational needs, the focus should shift from the specific means of communication towards the equally socially important quality of the complex process of communication, which is centered on the personality of the handicapped child.

Assessing the Quality of Management of Transformation Processes in Economic Systems

2020 ◽  
Vol 26 (9) ◽  
pp. 952-956
Author(s):  
M. V. Malyshkina ◽  
M. V. Miroslavskaya
Keyword(s):  
Systems Approach ◽  
Mutual Influence ◽  
Organizational Transformation ◽  
Quality Criterion ◽  
Economic Transformation ◽  
Economic Systems ◽  
Negative Consequences ◽  
Management Actions ◽  
Transformation Processes

Aim. The presented study aims to develop the methodology for assessing the quality of management of organizational transformation processes. Tasks. To achieve the set aim, the authors solve the following problems: determine the essence and content of socio-economic transformation, formulate quality assurance principles for the management of transformation processes, draw attention to the problem of selecting a unified quality criterion for the management of organizational transformation processes. Methods. This study uses general scientific methods of cognition, including analysis and synthesis. It also applies a systems approach to identify the major problems of assessing the quality of management of transformation processes, including the problem of selecting a unified quality criterion for the management of transformation processes and formulating the principles of ensuring the quality of management of transformation processes. Results. The global problem of managing transformation processes in the economic system consists in the complexity of the managed processes, which increases due to the multidimensionality, mutual influence, and the resulting uncertainty of interactions between the elements of the system. It is concluded that the methodology for assessing the quality of management of transformation processes is based on the principle of integrating separate measures to improve the quality of management of system elements into a single system of management actions and the principle of ensuring that management actions are primarily aimed at preventing possible negative consequences of the transformation of economic systems, i.e. reducing the potential impact of unfavorable events and their consequences. To assess the effectiveness of targeted management actions and productive actions aimed at organizing, controlling, and guiding the transformation process, the authors actualize the problem of selecting an adequate quality criterion for the management of transformation processes in economic systems and put forward a hypothesis about a possible unified criterion of management quality. Conclusions. The principle of integrating separate measures to improve the quality of management of system elements and the principle of ensuring that management actions are aimed at preventing possible negative consequences lie at the core of the methodology for assessing the quality of management of transformation processes in economic systems. The quality assessment methodology should be developed in the direction of finding a unified quality criterion for managing transformation processes in economic systems.

scholarly journals Influence of Parasitic Resistances on the Input Resistance of Buck and Boost Converters in Maximum Power Point Tracking (MPPT) Systems

Electronics ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1464
Author(s):  
Marcin Walczak ◽  
Leszek Bychto
Keyword(s):  
Input Resistance ◽  
Load Resistance ◽  
Maximum Power ◽  
Solar Panels ◽  
Maximum Power Point ◽  
Boost Converters ◽  
Pv Systems ◽  
Point Tracking ◽  
Pv Panel ◽  
Power Point

DC/DC converters are widely used in photovoltaic (PV) systems to maximize the power drained from solar panels. As the power generated by a PV panel depends on the temperature and irradiance level, a converter needs to constantly modify its input resistance to remain at the maximum power point (MPP). The input resistance of a converter can be described by a simple equation that includes the converter load resistance and the duty cycle of the switching signal. The equation is sufficient for an ideal converter but can lead to incorrect results for a real converter, which naturally features some parasitic resistances. The goal of this study is to evaluate how the parasitic resistances of a converter influence its input resistance and if they are relevant in terms of MPPT system operation.

scholarly journals Molecular Hydrogen Maintains the Storage Quality of Chinese Chive through Improving Antioxidant Capacity

Plants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1095
Author(s):  
Ke Jiang ◽  
Yong Kuang ◽  
Liying Feng ◽  
Yuhao Liu ◽  
Shu Wang ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Molecular Hydrogen ◽  
Practical Significance ◽  
Total Phenolic ◽  
Guaiacol Peroxidase ◽  
Storage Quality ◽  
Decay Index ◽  
Chinese Chive ◽  
Dpph Scavenging

Chinese chive usually becomes decayed after a short storage time, which was closely observed with the redox imbalance. To cope with this practical problem, in this report, molecular hydrogen (H2) was used to evaluate its influence in maintaining storage quality of Chinese chive, and the changes in antioxidant capacity were also analyzed. Chives were treated with 1%, 2%, or 3% H2, and with air as the control, and then were stored at 4 ± 1 °C. We observed that, compared with other treatment groups, the application of 3% H2 could significantly prolong the shelf life of Chinese chive, which was also confirmed by the obvious mitigation of decreased decay index, the loss ratio of weight, and the reduction in soluble protein content. Meanwhile, the decreasing tendency in total phenolic, flavonoid, and vitamin C contents was obviously impaired or slowed down by H2. Results of antioxidant capacity revealed that the accumulation of reactive oxygen species (ROS) and hydrogen peroxide (H2O2) was differentially alleviated, which positively matched with 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and the improved activities of antioxidant enzymes, including superoxide dismutase (SOD), guaiacol peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX). Above results clearly suggest that postharvest molecular hydrogen application might be a potential useful approach to improve the storage quality of Chinese chive, which is partially achieved through the alleviation of oxidative damage happening during the storage periods. These findings also provide potential theoretical and practical significance for transportation and consumption of perishable vegetables.

scholarly journals Mutual Influence of Psoriasis and Sport

Medicina ◽  
2021 ◽  
Vol 57 (2) ◽  
pp. 161
Author(s):  
Paolo Custurone ◽  
Laura Macca ◽  
Lucrezia Bertino ◽  
Debora Di Mauro ◽  
Fabio Trimarchi ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Physical Activity ◽  
Metabolic Syndrome ◽  
Mutual Influence ◽  
Sport Activity ◽  
Joint Involvement ◽  
Indirect Benefits ◽  
The Impact

The link between psoriasis and sport is a controversial issue. The topic has been poorly investigated, and nowadays there are many unsolved questions, dealing with the role of psoriasis in influencing the sporting habits of patients and, vice versa, the impact of sport activity on course, severity and extent of the disease, with particular regard to the indirect benefits on cardiovascular risk and metabolic syndrome. Moreover, the role of physical activity on patients’ quality of life and the potential limitations on physical activity due to joint involvement have not been well elucidated until now. In this narrative review we will try to provide answers to these queries.

ENTREPRENEURIAL ACTIVITIES MODELING IN THE HOSPITALITY INDUSTRY BASED ON THE USE OF LAND CADASTRAL VALUATION INDICATORS

2017 ◽  
Author(s):  
Raisa Kozhukhіvska ◽  
◽  
Оlena Sakovska ◽  
Keyword(s):  
Financial Support ◽  
Hospitality Industry ◽  
The State ◽  
Practical Significance ◽  
Time Intervals ◽  
Main Disadvantage ◽  
Entrepreneurial Activities ◽  
The City ◽  
Cluster Level

The article examines the organizational basis of modeling entrepreneurial activities in the hospitality industry based on the use of indicators of cadastral assessment of land. The analysis of practical aspects of updating the results of cadastral assessment of lands of settlements of Cherkassy region has been carried out. It is stated that the cadastral assessment should take into account market situations and trends as much as possible. For the territories of localities the term of actualization in the context of revaluation should be minimum and economically justified. It is designated that the updating of the results of the state cadastral assessment of land requires significant modernization aimed at improving the quality of land assessment work and adequate replenishment of budgets at all levels. The mechanism and features of performance of works on actualization of the state cadastral estimation of the lands of settlements in the territory of Cherkassy region have been analyzed. As a result of the study, it has been found that the main disadvantage of modeling the cadastral assessment of land settlements is: the duration of time intervals between rounds of revaluation, which causes rapid aging of information. The reason for this case is related with the financial support of the works and their scale. Mechanisms for prompt updating of information on the value of land for entrepreneurial activities in the hospitality industry in Cherkassy region have been proposed. The considered method of determining the normative monetary valuation of land takes into account the most important indicators of this industry and is practically significant in collecting information and calculating all indicators in conducting cadastral valuation of land for entrepreneurial activities in the hospitality industry of Cherkassy region. The practical significance of the study is to assess the cadastral condition of land and calculate the specific cadastral value of the city of Uman, as the territory where the hospitality industry is the most developed in Cherkassy region. Due to the clarification of the specific indicator of cadastral value, the price of one square meter of such objects will increase which will allow to proportionally increase the tax component and increase the profitability of budgets at the cluster level

scholarly journals Politicization of Religion in Theoretical and Terminological Understanding

2021 ◽  
Vol 1 (1) ◽  
pp. 27-40
Author(s):  
M. Kh. Abdullaev
Keyword(s):  
Mutual Influence ◽  
Human Life ◽  
Religion And Politics ◽  
Political Activity ◽  
Practical Significance ◽  
The Political ◽  
Spiritual Values ◽  
Theoretical Understanding ◽  
Political Role ◽  
The Rich

The article is devoted to an actual interdisciplinary problem at the intersection of political science and religious studies – the discourse of the political in religion, the politicization of religion, the artificial transfer of purely spiritual values, phenomena and categories into the political field in order to use religion for political purposes. The author considers the problem from two angles: (1) the politicization of religion for mercenary purposes and (2) the clergy’s political activity based on a deliberately politicized religious teaching that has a strong political platform (ideology) at its core. This study is purely theoretical, and nevertheless the author undertakes a number of empirical digressions in order to demonstrate how the politicization of religion manifests itself in the socio-political sphere of human life. Thus, the main problem of the study should be designated as a theoretical understanding and disclosure of the practical significance (i.e., risks and effects) of the religion politicization’s negativity and how it could effect on religious groups. The article identifies the objective factors of the mutual influence of religion and politics, the presence of strong political origins in a number of creeds, and the rich historical experience of the political role of faith in society.

scholarly journals Development of methods for equalizing level networks

2020 ◽  
Vol 21 (1) ◽  
pp. 58-65
Author(s):  
Ekaterina N. Esina ◽  
Vladislava V. Likhodeevskaya
Keyword(s):  
Measurement Accuracy ◽  
Closed Loop ◽  
Mutual Influence ◽  
Parametric Method ◽  
Network Configuration ◽  
Nodal Points ◽  
True Values ◽  
Intensive Development ◽  
Method Of Adjustment

The article is devoted to comparison of methods of calculating the approximate elevations of nodal points when adjusting leveling networks by strict and non-strict methods. Ensuring geomechanical monitoring of the mutual influence of constructed and operated objects is important in the intensive development of underground space of megacities, the construction of unique objects and structures. In the course of the research, mathematical models of level networks were developed and presented in the form of a closed loop and a set of open polygons. Analysis of modeling allows to determine the feasibility of applying the knot method by Professor V.V. Popov instead of the parametric method of adjustment. It is established that the quality of the results of strict equalization depends entirely on the quality of measurements, since deviations from the true values do not exceed the measurement error. The research has shown that it is possible to simplify the processing of monitoring data and evaluation of various configuration options for leveling networks, using algorithms for calculating approximate marks of nodal points. This makes it easier to process monitoring results and evaluate various network configuration options while ensuring the required level of measurement accuracy.

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