Arcless opening of direct current circuits in technical systems

Operation of the proposed DC circuit breaker consists in the fact that the closing of the thyristor in the DC power circuit with an inductive load results from opening the auxiliary circuit with a current value several fold less than the load current. The power and auxiliary circuits are connected by means of a current transformer having counter switch windings. After switching, the load is shunted by a diode and does not affect the transition process. Simulations and experimental tests of the DC circuit breaker model showed its performance capability, and the breaker can be used for switching in existing DC high current circuits with inductive loads

Assessment of commercial potential and prospects of carrying outscientific research from a position of a resource efficiency and resourcesaving

The growth of population leads to the fact that natural resources are being used op very fast. Making our world moreresource efficient is a way to achieve economic and social goals at lower cost. Thus, the implementation of any projectsignificantly depends on economic efficiency and its potential of technology. Nowadays there are different types ofimplementation of relay protection. Thus, to make a project successful it is necessary to choose the most modern, highdemand,knowledge-based variant of implementation of relay protection. In this paper comparative assessment of adesirable development of technological projects based on the implementation of relay protection on the power lines of220kV has been carried out. Moreover, SWOT analysis for microprocessor option of relay protection implementationhas been done

Company business start-up

Předmětem vybraného tématu pro moji Bakalářskou práci se stal projekt - otevření fitness klubu ve městě Volgograd pod názvem "Fit34Life". Cílem této Bakalářské práce se stalo psaní komplexního podnikatelského plánu s výpočty a ekonomickou efektivitou zavedení projektu. Pro dosažení cílů byly zadány následující úkoly: -Studie podnikatelského plánování -Rozbor struktury podnikatelského plánu. -Rozpracování podnikatelského plánu. -Hodnocení možných rizik budoucího projektu. -Studie ekonomických stran podnikatelského plánu. -Výpočet efektivity podnikatelského plánu. V práci byly použity praktické i všeobecně logické metody. Bakalářská práce objemem (rozsahem) 71 stran, se skládá z úvodu, dvou kapitol, závěru, seznamu literatury a přílohy. První kapitola "Teoretická část", odhaluje základní pojmy obchodního plánování a zkoumá také základní prvky metodiky přípravy podnikatelského plánu. Druhá kapitola "Praktická část", obsahuje podnikatelský plán na otevření fitness klubu, s výpočty ekonomické efektivity projektu s hodnocením potencionálního rizika. Téma rozvoje podnikatelského plánování je v Rusku momentálně velmi aktuální kvůli nedostatku zkušeností a informací. Různé aspekty obchodního plánování postrádají teoretický a metodologický základ, a to zejména v souvislosti s marketingovými výzkumy a organizačními plány, což snižuje kvalitu podnikatelských plánů. V řadě případů vede k nesprávným rozhodnutím. Pro rozvoj ekonomiky je důležité aplikovat moderní metody podnikatelského plánování.The subject of the study on the chosen topic was the project of starting-up a fitness club in Volgograd, entitled Fit34Life. The aim of bachelor work was to write a full-scale business-plan with calculations of economic efficiency of the project implementation. In order to achieve the goal following tasks were set: -Essence studying of business-planning; - Consider the structure of business-plan; -Development of a business-plan; -Evaluation of possible risks of the future project; -Studying the economic side of the business plan; -Efficiency calculation of the business plan. The practical method was used, as well as a general-logic method. Bachelor thesis is 71 pages in volume, consists of introduction, two chapters, conclusion, bibliography and supplements. The first chapter is Theoretical part reveals the basic concepts of business planning, as well as consider the main elements of the methodology of the business plan. The second chapter is Practical part includes a business plan to open a fitness club, with calculations of economic efficiency of the project and risk assessment. Modernity and the relevance of this work is that in Russia have not yet accumulated enough experience to develop business plans. Lack of theoretical and methodological development of various aspects of business planning, and especially those related to market research and organizational aspects, reduces the quality of the developed business plans and in some cases leads to wrong decisions. In this regard, the use of modern methods of business planning is an urgent task in modern conditions of economic development.The subject of the study on the chosen topic was the project of starting-up a fitness club in Volgograd, entitled Fit34Life. The aim of bachelor work was to write a full-scale business-plan with calculations of economic efficiency of the project implementation. In order to achieve the goal following tasks were set: -Essence studying of business-planning; - Consider the structure of business-plan; -Development of a business-plan; -Evaluation of possible risks of the future project; -Studying the economic side of the business plan; -Efficiency calculation of the business plan. The practical method was used, as well as a general-logic method. Bachelor thesis is 71 pages in volume, consists of introduction, two chapters, conclusion, bibliography and supplements. The first chapter is Theoretical part reveals the basic concepts of business planning, as well as consider the main elements of the methodology of the business plan. The second chapter is Practical part includes a business plan to open a fitness club, with calculations of economic efficiency of the project and risk assessment. Modernity and the relevance of this work is that in Russia have not yet accumulated enough experience to develop business plans. Lack of theoretical and methodological development of various aspects of business planning, and especially those related to market research and organizational aspects, reduces the quality of the developed business plans and in some cases leads to wrong decisions. In this regard, the use of modern methods of business planning is an urgent task in modern conditions of economic development

APPLICATION OF MODERN GEODETIC TECHNOLOGIES AND SATELLITE POSITIONING SYSTEMS IN THE SURVEY OF RAILWAY STATIONS

The article presents methods of shooting train stations when performing a tool check of plan and profile station tracks in accordance with existing regulations. The normative requirements, measuring means, shortcomings of existing technologies of instrumental check of the plan and a profile of station ways and possibilities of the modern technologies based on 3D models and pos-sibilities of their application for the Railways are considered. The necessity of the presentation of railway tracks and infrastructure in digital form (3D) is substantiated. The concept of digital data on railway track and elements of infrastructure should be invested not by picket, but by three-dimensional geodetic coordinates, which will allow the railway track and its elements to be dis-played in digital space. Fragments of reporting documentation are shown. The perspective developments for full-scale survey of station ways made on the basis of UAV and complex "Profile" are considered, the results of experimental and methodical works received in 2018g on railroad ZS are given, positive conclusions are drawn.</jats:p

CREATION OF ELECTRONIC VERSION OF SCALE PLANS OF RAILWAY STATIONS

This article describes the stages of creating electronic versions of scale plans of stations, using measurements obtained by various geodetic tools and complexes. The features of processing of ma-terials obtained by complex "Profile"are described. The General algorithm of formation of the scale plan of railway stations is shown. In the course of all processing of materials the railway way is con-sidered as the uniform massif consisting of points of an axis of the way having both planned posi-tion, and high-rise. This approach allows you to fully analyze the plan and profile of the station path as a separate element of the station, and its relationship with other objects. Perform automatic calcu-lation of picketage, spacing and dimensions of buildings.мThe problems of data export to the geoin-formation database of the West Siberian railway are indicated.</jats:p

Computational and experimental studies of hydrodynamic instabilities and turbulent mixing: Review of VNIIEF efforts. Summary report

The report presents the basic results of some calculations, theoretical and experimental efforts in the study of Rayleigh-Taylor, Kelvin-Helmholtz, Richtmyer-Meshkov instabilities and the turbulent mixing which is caused by their evolution. Since the late forties the VNIIEF has been conducting these investigations. This report is based on the data which were published in different times in Russian and foreign journals. The first part of the report deals with calculations an theoretical techniques for the description of hydrodynamic instabilities applied currently, as well as with the results of several individual problems and their comparison with the experiment. These methods can be divided into two types: direct numerical simulation methods and phenomenological methods. The first type includes the regular 2D and 3D gasdynamical techniques as well as the techniques based on small perturbation approximation and on incompressible liquid approximation. The second type comprises the techniques based on various phenomenological turbulence models. The second part of the report describes the experimental methods and cites the experimental results of Rayleigh-Taylor and Richtmyer-Meskov instability studies as well as of turbulent mixing. The applied methods were based on thin-film gaseous models, on jelly models and liquid layer models. The research was done for plane and cylindrical geometries. As drivers, the shock tubes of different designs were used as well as gaseous explosive mixtures, compressed air and electric wire explosions. The experimental results were applied in calculational-theoretical technique calibrations. The authors did not aim at covering all VNIIEF research done in this field of science. To a great extent the choice of the material depended on the personal contribution of the author in these studies

Computational and experimental studies of hydrodynamic instabilities and turbulent mixing (Review of NVIIEF efforts)

This report describes an extensive program of investigations conducted at Arzamas-16 in Russia over the past several decades. The focus of the work is on material interface instability and the mixing of two materials. Part 1 of the report discusses analytical and computational studies of hydrodynamic instabilities and turbulent mixing. The EGAK codes are described and results are illustrated for several types of unstable flow. Semiempirical turbulence transport equations are derived for the mixing of two materials, and their capabilities are illustrated for several examples. Part 2 discusses the experimental studies that have been performed to investigate instabilities and turbulent mixing. Shock-tube and jelly techniques are described in considerable detail. Results are presented for many circumstances and configurations