05.00.00 Technical science
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SOURCES OF ELECTRICAL ENERGY OF AIRCRAFT ELECTRIC POWER SUPPLY SYSTEMS: CONDITION AND PERSPECTIVES
DescriptionAccording to its operating principles, generators of aircraft electric power supply systems do not differ from the similar generators of transporting and stationary systems, but have range of peculiarities: low weight and dimensions, high density of armature current, compulsory cooling (air and liquid), high frequency of rotor spinning. The article considers main requirements, imposed to generators of flight vehicle and the construction peculiarities and main physical and operational characteristics of generators applied in modern flight vehicles. It is suggested to use noncontact electrical machines as sources of electrical energy in the aircraft electric power supply systems: synchronous generators with impulses from permanent magnets and asynchronous generators with capacitive impulse. To improve physical and operational characteristics of generators and aircraft electric power supply systems it is suggested to refuse from permanent frequency spinning drivers which have low converters as stabilizer of voltage and frequency current of electrical energy source. The peculiarities of its operation are considered, its advantages and disadvantages. It is possible to improve characteristics of aircraft electric power supply systems by means of study of the electromagnetic compatibility of the main functional system elements and by means of application of non-contact electrical devices, applied in the guard and control systems, made on the basis of power and electronic devices
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POWER SOURCES OF OPERATION, CONTROL AND PROTECTION DEVICES
DescriptionCurrently operating in autonomous systems of power supply DC voltages power sources are secondary sources for operation devices, protection and control of generators, motors, stabilizers and inverters have relatively low operational performance. The work proposes to improve the weight and the size of power supplies to apply a high frequency link in their designs. We provide structural designs and the peculiarities of operation of secondary power sources with a high frequency link. This article discusses the fundamental electrical circuits of pulse regulators, converters based on resonant inverters and transformers with rotating magnetic field. The use of resonant inverters in power sources will significantly improve their weight and overall dimensions. In addition, the use of secondary sources of supply for transformers with rotating magnetic field will simplify their design and reduce the level of electromagnetic interference generated by semiconductor devices. The features of operation of pulsed regulators and prospective structuralschematics converters discussed in the article, performed on resonant inverters and transformers with rotating magnetic field, will increase the effectiveness of pre-work on the development of secondary power sources with improved operational and technical characteristics for devices of operating, control and protection
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TO THE ALGORITHM OF KNOWLEDGE, SKILLS AND HABITS REALIZING BY INFORMATIONAL TECHNOLOGIES
DescriptionGeneral algorithm of knowledge learning, skills and habits mastering in the process of academic discipline with the use of informational technologies is described in this article.
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TO ANALYSIS OF TECHNOLOGICAL AND TECHNICAL MEANS OF PREPARING HIGH GUALITY FORAGE
DescriptionAn original design of a piston press, performing material pressing, due to case design tapered piston and the matrix, has been proposed for the first time
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Description
The article investigates the possible pathways for the formation of crotonaldehyde in wine production in the result of the activity of wine yeast and lactic acid bacteria. It established that exposure to exhaust gases, noble rot, pathogens and pests on grape plant does not lead to the biosynthesis of crotonaldehyde in grape berry. The experimental data to identify probable pathways for the formation of crotonaldehyde during vinification has been presented. The effect of the test substance on the life of yeasts and lactic acid bacteria has been estimated
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TO THE QUESTION OF HARROWING AND SIMULTANEOUS FEEDING
DescriptionThe technology of cultivation of most crops provides pre - and post-emergence weeding of crops, and their feeding with the availability of soil nutrients. According to the used underlying technology, these operations are performed separately. The harrowing of crops after germination is necessary for weed control, the destruction of the soil crust for access of air to the root system and partial thinning of dense crops. Further destruction of weeds on crops are herbicides, high-quality entry which provide sprays. The latter can provide small and ultra-low volume spraying in high performance and environmental requirements. However, separate execution of technological operations for fertilizing and harrowing reduces the quality of work, increases the cost of production. The proposed combination of technological operations on a harrowing of crops different crops simultaneously with feeding plants solid mineral fertilizers. The combination of technological operations for one pass of machine-tractor unit in the field provides a reduction of the fleet, its capital intensity, the energy, cash costs, and hence competitiveness of products. The studies proposed new technical support processes, technological scheme of the multifunctional unit to combine the operations of feeding and harrowing of crops
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CHOOSING SOLAR PHOTOVOLTAIC PLANT
DescriptionPromising is the direction and, above all, in matters of energy saving and energy efficiency of Autonomous systems of power supply, the use of renewable sources-newable energy as a major source of energy for consumers in remote areas. Here priority is given to solar energy. Since solar radiation can be change place not only in heat and electrical. The article contains three main structural schematics of electricity supply with solar power plants. The features of their work are disclosed, as well as an algorithm for calculating solar energy systems, the sequence of which is to define the required parameters, the daily energy consumption by consumers of electric power, the calculation capacity of the battery, the choice of the inverter and determining the area of solar batteries. The article reveals the conditions that affect the calculation of the PV system. It is shown that the greatest efficiency, including economic and reliability we have at combined (hybrid) Autonomous system, which was carried out with both solar power and wind power and gas stations. The important matters of improving the reliability of solar systems are the introduction to the design of a new element of the base, and first and foremost, Autonomous inventors performed on a single-phase transformer with a rotating magnetic field
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THE PROBLEM OF CLASSIFICATION AND BASIC REQUIREMENTS FOR PROJECTING WIND-ELECTRICAL INSTALLATIONS
DescriptionThe article describes the principles of classification, as well as the basic requirements and features of wind power plants projecting
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TO THE QUESTION OF MODELING OF OSCILLATORY PROCESS BY MEANS OF OBJECT-ORIENTED PROGRAMMING
DescriptionIn this article, we have presented the study and implementation of the physical model of motion of two coupled pendulums with use of numerical methods. When building the model we were using the method of Euler solutions of differential equations, which displays pendulums visual motion, as well as building graphics of functions of speed, angle and acceleration depending on time with high reliability. We have generated equation of motion for generalized coordinates for the first and second mathematical pendulum. The generated application implements a physical model of a double mathematical pendulum, commit sustained oscillations with the ability to change the basic parameters: deflection angle, speed, mass and length of the rod in C++ language by programming environment “Embarcadero RAD Studio”. This application can be used as a model of a double mathematical pendulum in the study of oscillations, as a methodical manual and a virtual laboratory in physics, informatics and programming classes – for demonstration, study and create applications in the objectoriented C++ programming language
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Description
The work is scientific and practical in nature, same as the discussed process of optimization of power losses in power networks based on the use of the transportation problem, namely the rules of the minimum element of the transport matrix, which is a valid solution. The mechanism of the improvement of the obtained feasible solutions to the tasks focuses on using the potential method, assigning each row and column of the matrix their corresponding potential. Using a basic variable and manipulating the elements of the transport matrix according to a specific algorithm, we implement the construction of a new support plan. Based on the plan and its acyclic, we build two cycles and determine the values of the estimates between direct and indirect transportation costs per unit of output. The resulting algorithm makes it easy to program all computational operations and quickly obtain the result of the optimization of power losses in the design of the electricity network, thereby reducing the economic and technological costs. As a result of joint use of transportation problems and potential method, we could find the optimal solution based on improved solutions more efficiently, and a scheme of optimal electric network. As consumers, in practice, there may be urban and agricultural, industrial enterprises, regional and district subordination, including industrial, agricultural and individual customers