05.00.00 Technical science
-
SPECTRAL CHARACTERISTICS OF THE SINUSOIDAL MINIMUM (FREQUENCY) SHIFT-KEYING
DescriptionSignals with the sinusoidal minimum (frequency) shift-keying (SMSK) which impulse form depends on parameter µ are considered. Expression for power spectral density (PSD) of SMSK signals at various values of parameter µ is obtained. Results of PSD calculations and effective bandwidth of signals by various criteria are presented
-
RISK MANAGEMENT IN WOODWORKING
DescriptionThe article deals with urgent questions concerning activities of woodworking industries, which face tough economic situation. Nevertheless, these enterprises reveal a definite growth of output in some kinds of products, such as fuel pellets, window units, special timber assortments, etc. The problems about possible risks connected with equipment handling were identified, which has physical and intellectual wear, as most of it has been operating since 1980. On the basis of accomplished investigations of normative and technical sources the documents were specified, which establish safety regulations for operating equipment and requirements for risk assessment techniques. The necessity of their improvement is also determined. Taking into consideration peculiarities of management of woodworking production process, the analysis was carried out in order to estimate the factors, which influence the quality of mechanical treatment by the method of 5M. Following the observations and processing of statistical data it was established that equipment and personnel show the greatest impact on the quality of half-finished and final products. Risks evaluation method for woodworking industries is suggested with due account for equipment safety parameters, which includes determination of consequences, risk probability, risk level on scale factored “high”, “medium” and “low”. Much attention is paid to the items composed: rank matrix of two-factor model, with calculations of numerical values of risks, as product probability of occurrence and severity of consequences, and risk log. Three zones were appointed with the following risk levels: the first zone with weighting factor not less than 6, the second zone: 8-16, the third: 20-25. In course of investigation, it was detected that the highest risk factor, connected with equipment operation, is probability of mechanical injuries of hands and most possible – getting cuts. The flow chart of risks management during the woodworking production process is offered in accordance with all Union State Standard regulations R ISO 9001-2015 and GOST R ISO/MAC 31010-2011. The developed algorithm provides accomplishing performance of work on risks management in more available and short form with presentation of processing operations, actual doers, kinds of required normative documents and papers worked out within the enterprise
-
COMBINED SYSTEMS OF ELECTRICITY SUPPLY BASED ON RENEWABLE ENERGY SOURCES
DescriptionCurrently, there are widely used combined (hybrid) power systems in the world, made using renewable and conventional sources of energy. The article discusses a typical structural scheme of a combined system of electricity supply; it also shows the design and the characteristics of three types of structural circuit design of combined power systems and their main advantages and disadvantages. Peculiarities of the choice and calculation of parameters of the basic functional elements of the combined system have been presented. This study describes main characteristics of solar batteries and provides analytical expressions for the calculation of their main parameters. The main characteristics of batteries and the peculiarities of calculation of the capacity of storage batteries operating in autonomous systems have been listed. The features of selection of voltage inverters have shown that in addition to the nominal input and output voltage it is necessary to consider other characteristics that influence the work of autonomous power supply systems. It has been shown when it is desirable to use electromechanical generators to supply autonomous consumers. The types of structural solutions and the choice of the basic functional elements of combined power systems will increase the efficiency of their design
-
THE TASK OF FORECASTING OF PUBLICATION ACTIVITY
DescriptionIn the article questions of forecasting of publication activity and a problem of planning of actions on management of publicity activity of scientific collective are considered
-
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
-
MATHEMATICAL MODELING OF SPECIAL ELECTRIC DRIVES FOR THE EQUIPMENT OF OIL AND GAS BRANCH
DescriptionCreation of new types of special electric actuators for the oil and gas industry implies development of new approaches to simulation, design of the considered types of electric actuators. In addition, it requires development of new algorithms for creation of a complex of application programs of computer-aided design of special electric actuators. As process of simulation is quite labor consuming, it is offered to realize it gradually. In this article, the question of mathematical simulation of special electric actuators for the equipment of oil and gas branch using methods of electromagnetic conversion of energy is considered. Results of mathematical simulation were realized in the form of the program products, which are a part of system of computer-aided design
-
INNOVATIVE TECHNOLOGY OF DUALSTAGE OBTAINING RAW JUICE AND ITS PURIFYING IN SUGAR INDUSTRY
DescriptionThe typical scheme of sugar beet processing, used at most sugar beet factories in Russia has not been fundamentally changed for several dozens of years. As a result, the performance indicators of domestic beetprocessing enterprises are below the world average. The article considers the technology of two-stage extraction and subsequent lime-carbon dioxide raw juice purification with the separation of the preliming sludge and carrying out the carbonation treatment in one step. The theoretical foundations of a two-stage extraction of sucrose from sugar beet cossettes are described and the main criteria for its implementation are given. The chemistry of calcium compounds upon activation of a suspension of saturation precipitation, returned to a progressive preliminary defecation, is shown. On that the increasing of sedimentationfiltration properties of the preliming sludge is based that allows its separation on the existing equipment in based. The theoretical premises for carrying out saturation in a homogeneous liquid-liquid environment are given and practical principles for their realization are described. The comparative evaluation of existing and improved sugar beet processing technologies is carried out. The improved technology makes it possible to reduce the amount of raw juice while improving its purity, thereby reducing the consumption of auxiliary materials, fuel and energy resources, simplifying the technological scheme while improving the quality of the purified juice, namely, its higher purity, achieved by reducing the degree of transition of high-molecular compounds in it and increasing the effect of destruction of reducing substances
-
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
-
OPTIMIZING THE SHAPE OF A CENTRIFUGE ROTOR
DescriptionThe use of regenerated oils reduces the consumption of fresh oils for refilling, while oil filtration during the operation lengthens their service life and reduces the consumption of fresh oils for replacement. To restore waste oils, a variety of technological operations are used, based on physical, physicochemical and chemical processes. They are aimed at treating the oil in order to remove aging products and pollution from it. The studies have shown that the most effective means of recovering the quality of waste oils are small-size regeneration plants. The main difficulty in creating small-sized regeneration plants is the selection of a sufficiently effective, environmentally safe and economically justified method for the regeneration of waste oils, as well as its hardware design. This work is aimed at creating an efficient centrifugal cleaner
-
Description
The article examines the issues of increasing the efficiency of the system of technical operation of mobile agricultural machinery by means of monitoring the state of units and aggregates of the latter through diagnostics. The problems of complex diagnostics of diesel fuel equipment are investigated. The urgency of diagnosing a fuel injection pump without dismantling from the engine is shown from technical, economic and environmental points of view. The effect of operational malfunctions of some devices of fuel equipment on parameters of its operation as a whole is analyzed. On the basis of the analysis of diagnostic devices application, their grouping is suggested. The parameters to be studied in connection with peculiarities to decide whether it is possible to estimate the technical state of the fuel injection pump without dismantling from the internal combustion engine are indicated. Based on peculiarities of the fuel injection pump technical state estimation, a research program is developed and the results of the research are presented. Specific features of testing the fuel injection pump are indicated. Analysis of the results of the research shows that a smaller error in the change of the cyclic fuel feed rates supplied by the fuel injection sections takes place at the engine speed corresponding to the indicated power. The conclusion is made that the presented research results can be used as a basis for developing a technique (technology) for diagnosing the fuel injection pump without dismantling from the internal combustion engine