scholarly journals Control of Valve Converters with Natural Current Characteristics

2018 ◽  
Vol 155 ◽  
pp. 01047 ◽  
Author(s):  
Sergazy Mendybayev ◽  
Yermek Sarsikeyev ◽  
Dameli Kapanova
Keyword(s):  
Reactive Elements ◽  
Electric Force ◽  
Current Characteristic ◽  
Current Converter ◽  
Characteristic Features ◽  
Current Characteristics ◽  
Valve Converter ◽  
Modulating Functions ◽  
Parametric Source

The article considers the valve converter with a natural current characteristic, which is called the current of parametric, for which the primary is not the source of the electric force but a parametric source of current, to the output of which connected to the counter-parallel thyristor sets assembled on the bridge scheme. The control of thyristors in the current converter is carried out taking into account the characteristic features of the parametric source, to avoid overvoltage on its reactive elements, analyzed algorithmic and modulating functions of the system borne temporary diagrams.

scholarly journals Mathematical models of the electric arc of variable geometrical parameters based on static voltage-current characteristics

2019 ◽  
Vol 84 ◽  
pp. 02012
Author(s):  
Antoni Sawicki
Keyword(s):  
Mathematical Models ◽  
Cross Section ◽  
Electric Arc ◽  
Geometrical Parameters ◽  
Arc Length ◽  
Current Characteristic ◽  
Dynamic Character ◽  
Voltage Current Characteristic ◽  
Current Characteristics

The paper presents the Schellhase and Pentegov models utilizing static voltage-current characteristics for representing processes occurring in the electric arc. In the approximations of these characteristics variation in geometrical parameters, i.e. arc length and cross-section is taken into account. A modification of the Voronin-type models is also proposed, introducing a static voltage-current characteristic. In this way, it is possible to take into account distortions of the arc geometrical parameters of the static and dynamic character.

Single-pulse method for measuring the current-voltage characteristics of solar panels

2019 ◽  
Vol 1-2 (99) ◽  
pp. 24-29
Author(s):  
K.M. Bozhko ◽  
N.M. Zashchepkina ◽  
M.O. Markin ◽  
O.M. Markina
Keyword(s):  
Short Circuit ◽  
Single Pulse ◽  
Operational Parameters ◽  
Solar Module ◽  
Current Characteristic ◽  
Digital Oscilloscope ◽  
Solar Battery ◽  
Voltage Current Characteristic ◽  
Current Characteristics ◽  
Solar Batteries

Purpose: The purpose of the paper is to substantiate the new method of measuring the voltage-current characteristics of solar batteries based on the use of a digital oscilloscope and a special linear sweep device. Design/methodology/approach: To solve this problem, a test bench was developed on the basis of a solar radiation simulator. Findings: Practically it is proved that within the duration of a single pulse of 40 μs, it is possible to measure the voltage-current characteristics of an SB with a short-circuit current of up to 5.8 A. Research limitations/implications: The method is relevant for all types of solar batteries, but the measurements were carried out on serial samples of mono and polycrystalline silicon with a nominal output power of 30 to 140 W and a voltage of 12 V. Practical implications: The method can find its practical application in the development of an intelligent solar module. The technology of the intelligent module is based on the periodic removal of information on the operational parameters of the solar battery based on the measured voltage-current characteristic. Originality/value: Experimental confirmation of the effectiveness of the single-pulse measurement method of the voltage-current characteristic of a solar battery based on a linear current sweep.

Ultrastructural modification of cellular interactions in cancer tumor

1978 ◽  
Vol 36 (2) ◽  
pp. 318-319
Author(s):  
N. P. Dmitrieva
Keyword(s):  
Cancer Cells ◽  
Human Thyroid ◽  
Adjacent Cell ◽  
Main Role ◽  
Cellular Interactions ◽  
Electron Microscopic ◽  
Cancer Tumor ◽  
Normal Human ◽  
Characteristic Features

One of the most characteristic features of cancer cells is their ability to metastasia. It is suggested that the modifications of the structure and properties of cancer cells surfaces play the main role in this process. The present work was aimed at finding out what ultrastructural features apear in tumor in vivo which removal of individual cancer cells from the cell population can provide. For this purpose the cellular interactions in the normal human thyroid and cancer tumor of this gland electron microscopic were studied. The tissues were fixed in osmium tetroxide and were embedded in Araldite-Epon.In normal human thyroid the most common type of intercellular contacts was represented by simple junction formed by the parallelalignment of adjacent cell membranees leaving in between an intermembranes space 15-20 nm filled with electronlucid material (Fig. 1a). Sometimes in the basal part of cells dilatations of the intercellular space 40-50 nm wide were found (Fig. 1a). Here the cell surfaces may form single short microvilli.

High spatial resolution AEM observations of yttrium segregation in chromia scales grown on Co-45%Cr

1986 ◽  
Vol 44 ◽  
pp. 518-519
Author(s):  
K. Przybylski ◽  
A. J. Garratt-Reed ◽  
G. J. Yurek
Keyword(s):  
Spatial Resolution ◽  
Outer Surface ◽  
Maximum Concentration ◽  
High Spatial Resolution ◽  
Reactive Elements ◽  
Chromia Scales

The addition of so-called “reactive” elements such as yttrium to alloys is known to enhance the protective nature of Cr2O3 or Al2O3 scales. However, the mechanism by which this enhancement is achieved remains unclear. An A.E.M. study has been performed of scales grown at 1000°C for 25 hr. in pure O2 on Co-45%Cr implanted at 70 keV with 2x1016 atoms/cm2 of yttrium. In the unoxidized alloys it was calculated that the maximum concentration of Y was 13.9 wt% at a depth of about 17 nm. SIMS results showed that in the scale the yttrium remained near the outer surface.

Development of 200kV ultrahigh-resolution analytical electron microscope

1989 ◽  
Vol 47 ◽  
pp. 108-109
Author(s):  
T. Kaneyama ◽  
M. Naruse ◽  
Y. Ishida ◽  
M. Kersker
Keyword(s):  
Electron Microscope ◽  
Optical Constants ◽  
Materials Science ◽  
Objective Lens ◽  
The Finite Element Method ◽  
Ultrahigh Resolution ◽  
Analytical Electron ◽  
Analytical Electron Microscope ◽  
Characteristic Features ◽  
Better Than

In the field of materials science, the importance of the ultrahigh resolution analytical electron microscope (UHRAEM) is increasing. A new UHRAEM which provides a resolution of better than 0.2 nm and allows analysis of a few nm areas has been developed. [Fig. 1 shows the external view] The followings are some characteristic features of the UHRAEM.Objective lens (OL)Two types of OL polepieces (URP for ±10' specimen tilt and ARP for ±30' tilt) have been developed. The optical constants shown in the table on the next page are figures calculated by the finite element method. However, Cs was experimentally confirmed by two methods (namely, Beam Tilt method and Krivanek method) as 0.45 ∼ 0.50 mm for URP and as 0.9 ∼ 1.0 mm for ARP, respectively. Fig. 2 shows an optical diffractogram obtained from a micrograph of amorphous carbon with URP under the Scherzer defocus condition. It demonstrates a resolution of 0.19 nm and a Cs smaller than 0.5 mm.

Tolerance is theoretical and practical principles

1996 ◽  
pp. 13-23
Author(s):  
Mykhailo Babiy
Keyword(s):  
Religious Diversity ◽  
The Other ◽  
Nodal Points ◽  
Characteristic Features ◽  
The One ◽  
Ukrainian Society

Political ideological pluralism, religious diversity are characteristic features of modern Ukrainian society. On the one hand, multiculturalism, socio-political, religious differentiation of the latter appear as important characteristics of its democracy, as a practical expression of freedom, on the other - as a factor that led to the deconsocialization of society, gave rise to "nodal points" of tension, confrontational processes, in particular, in political and religious spheres.

Hard and light gamification in education: Which one to choose?

2020 ◽  
Vol 1 (1) ◽  
pp. 20-27
Author(s):  
E. V. Karmanova ◽  
V. A. Shelemetyeva
Keyword(s):  
Computer Games ◽  
Educational Process ◽  
Course Development ◽  
Learning Technology ◽  
Training Course ◽  
Resource Requirements ◽  
E Learning ◽  
Characteristic Features ◽  
Game Elements

The article is devoted to the implementation of gamification methods in the educational process. The characteristic features of light and hard gamification are presented. The appropriateness of using gamification when applying e-learning technology is considered. Classification of courses based on hard gamification taking into account the technological features of development is proposed: courses-presentations, courses — computer games, VR/AR courses. The article also illustrates the use of various game elements of easy gamification using the example of the module “Level up! — Gamification” of the Moodle LMS. The capabilities of this module can be used in an electronic course by any teacher who has the skills of working with the Moodle.The authors present the analysis of the development of a training course in sales techniques using hard and light gamification technologies, where the course development was assessed for its complexity, manufacturability, and resource requirements. The results of the analysis showed that the development of courses using hard gamification requires much more financial and time-consuming than the development of courses using light gamification.The article evaluates the results of the educational intensiveness intense “Island 10–22”, held in July 2019 in Skolkovo, in which 100 university teams, teams of research and educational centers, teams of schoolchildren — winners of competitions, olympiads, hackathons (“Young Talents”) participated. The results of the intense confirmed the effectiveness of the use of light gamification methods in adult training. Thus, the conclusions presented in the article reveal a number of advantages that light gamification has in comparison with hard gamification.

Budget as an Instrument of Reproduction of Bureaucracy in Russia

2006 ◽  
pp. 87-96
Author(s):  
Yu. Shvetsov
Keyword(s):  
The State ◽  
Economic Consequences ◽  
Material Base ◽  
Characteristic Features

The article considers the problem of bureaucratisation of the state and the most important social and economic consequences of this phenomenon. The essence of bureaucracy has been revealed, characteristic features of its functioning in Russia have been analyzed; the material base of bureaucracy and its dominating status in the society have been substantiated. The conclusion has been made that the process of changing the role of the budget to serve the interests of bureaucracy is being accomplished.

Tendencies of Forming a Multistructure Economy in Uzbekistan

2019 ◽  
Vol 5 (12) ◽  
pp. 305-311
Author(s):  
M. Ashurov ◽  
Yu. Shakirova ◽  
O. Turdibekov
Keyword(s):  
Corporate Governance ◽  
Private Sector ◽  
Modern Corporation ◽  
The Republic ◽  
Characteristic Features

The article discusses some issues of the formation of a multistructure economy in the Republic of Uzbekistan. The authors performed an analysis of the processes of privatization and privatization in the country. The general tendencies of privatization by stages and results are revealed and generalized. The characteristic features of the stages of denationalization are studied. The formation of the private sector and on the basis of this form of joint stock companies. The need for improving the mechanism of corporate governance in a modern corporation is highlighted.

CAPRICCIOʼS GENRE IN MANDOLIN MUSIC AT THE END OF THE 19th – THE EARLY OF THE 20th CENTURIES (for example of the concert pieces by С. Munier)

2019 ◽  
pp. 60-71
Author(s):  
N. V. Bashmakova ◽  
K. V. Kravchenko
Keyword(s):  
19Th Century ◽  
Analytical Methods ◽  
17Th Century ◽  
Point Of View ◽  
Historical Approach ◽  
The Creation ◽  
Characteristic Features ◽  
Concert Works ◽  
In The Beginning ◽  
The 19Th Century

The purpose of this article is process of analyzing in reference to concert capriccio by C. Munier for mandolin with piano («Bizzarria», op. 201, Spanish сapriccio, op. 276) from the point of view of their genre specificity. Methodology. The research is based on the historical approach, which determines the specifics of the genre of Capriccio in the music of the late 19th and early 20th centuries and in the work of C. Munier; the computational and analytical methods used to identify the peculiarities of the formulation and the performing interpretation of the original concert pianos for mandolins with piano that, according to the genre orientation (according to the composerʼs remarks), are defined as capriccio. Scientific novelty. The creation of Florentine composer,61mandolinist-vertuoso and pedagog C. Munier, which made about 300 compositions, is exponential for represented scientific vector. Concert works by C. Munier for mandolin and piano, created in the capriccio genre, were not yet considered in the art of the outdoors, as the creativity and composer’s style of the famous mandolinist. Conclusions. Thus, appealing to capriccio by С. Munier, which created only two works, embodied in them virtually all the evolutionary stages of the development of genre. In his opus of this genre there are a vocal, inherent in capriccio of the 17th century solo presentation, virtuosity, originality, which were embodied in the works of 17th – 18th centuries and the national color of the 19th century is clearly expressed. Thus, the Spanish capriccio is a kind of «musical encyclopedia» of national dance, which features are characteristic features of bolero, tarantella, habanera, and so forth. The originality of opus number 201 – «Bizzarria», is embodied in the parameters of shaping (expanded cadence of the soloist in the beginning) and emphasized virtuosity, which is realized in a wide register range, a variety of technical elements.

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