The article proposes an analytical description of the deformation diagrams of concrete and pre-stressed high-strength reinforcing steel used for development of calculation methods of reinforced concrete elements with combined prestressing. In the developed method of calculation is the rectangular stress distribution in the compressed area of the flexible reinforced concrete element is adopted actual curved that in the case where the relative height of the compressed zone of the cross section close to the boundary ξ ξR, significantly clarifies the calculation. With this purpose, the curve σв – EV, obtained at a Central compression of the concrete prisms.
Keywords: stress-strain diagram of concrete, stress-strain diagram of steel
Details are given as for the results of production researches of reliability of Tunnelling Combines KP21, produced by JSC Kopeisk Engineering Plant, in conditions of Almaznaya Mine of Coal Company "Gukovugol" when driving preparatory developments with section up to 16 sq.m and strength of country rock up to 7 units according to Protodyakonov Rock Strength Scale. The obtained data allowed to define average operating time before breakage, as well as to make the list of details and knots having the greatest effect on reliability of the combine. The results processed allowed to calculate numerical characteristics of empirical distribution, which are similar to numerical characteristics of a random variable: ensemble average, dispersion, average quadratic deviation, variation coefficient, etc.
Keywords: tunnelling combine of selective action, reliability, operating time before breakage
Technique of modeling operation of a loader on the basis of method of statistical tests is given in the article and the way of defining current specific expenses connected with operation of loader of a certain design and statement of tasks on their improvement is considered. Modeling the process of loader operation pursues the aim to define specific expenses of consumer on operating the car taking into account casual stream of refusals and restoration of operating state of separate knots and parts of the car at any moment of effective life, with possibility of making decision on efficiency of application of a certain machine design, as well as possibility of forecasting expected indicators of reliability and optimum terms of operation. Basic data and results of comparative analysis of expenses of consumer on operation of serial car 2PNB2 and new sample of MPNK car are given.
Keywords: modeling, method of statistical tests, specific expenses, mine loaders
The article describes the results of simulation of a five-channel inverter with scalar control the motor speed. Briefly describes the principles of a scalar control, the structure of the five-channel inverter, as well as five-channel method of controlling the inverter using the method of double-zero sequence voltage (DZV). The structure of the model and the simulation results, confirming the possibility of using a five-channel inverter with scalar control the motor speed is considered.
Keywords: motor, speed control, scalar control, five-channel inverter, Simulink
This article describes the features of the implementation of the control unit stepper motor rotate camera mobile robotic platform using domestic components. Structure of a vector controller for a stepper motor analyzed. Selection of the control of the microcontroller for stepper motor control system is produced. The block diagram of the control unit stepper motor was developed.
Keywords: mobile robotic platform, stepper motor, motor control, vector control, industrial electronics
The main maintenance of a diversification of production as activity of subjects of managing is considered. being shown in purchase of the operating enterprises, the organizations of the new enterprises, redistribution of investments in interests of the organization and development of new production on available floor spaces. The most important organizational economic targets of a diversification of management are presented by innovative activity of the industrial enterprise.
Keywords: heat transfer, coefficient of heat transfer, thermal conductivity, similarity criteria, electric analog, vertical pipe, fluid, air, hot-water boiler
The investigations of the crystal structure, grain structure and dielectric properties of high-temperature multiferroic Bi1-x LaxFeO3 were carried out over a wide concentration range x = 0.00-0.50.
Keywords: multiferroic crystal structure, grain structure, dielectric properties
The investigations of the crystal structure, grain structure and dielectric properties of high-temperature multiferroic Bi1-хPrxFeO3were carried out over a wide concentration range x = 0.00-0.50.
Keywords: multiferroic crystal structure, grain structure, dielectric properties
The work contains the approximation of the third boundary value problem of schemes of high order. The approximation of the operator of the convective and diffusive transport difference schem were obtained, which has the fourth-order approximation error. The discrete operator diffusive transport in the absence of the influence of the boundary was considered.The construction of schemes of higher order accuracy approximates the operator diffusive transport in the border nodes in the case of boundary conditions of the third kind with the second order of accuracy was found.
Keywords: Schemes of high order, diffusion, diffusion transfer, discrete operator, approximation, boundary conditions, boundary value problem, finite-difference scheme
The work contains the construction and software implementation of related software systems designed for mathematical modeling of processes occurring in coastal water systems. The space-two-dimensional model of sediment transport in shallow waters allows to forecast the dynamics of bottom topography changes by reason of the movement of water and solid particles, to take into account the porosity of the soil, the critical shear stress at which begins the movement of sediment, turbulent exchange, dynamically changing geometry of the bottom, wind currents and friction on the bottom. The mathematical model of motion of a multicomponent air, takes into account factors such as the transport of pollutants and heat; the effect of vegetation; change in the coefficient of turbulent exchange; water transfer from the liquid to the gaseous state and others.
Keywords: multiprocessor computer system, grid equations, suspended solids, sediment
The calculation of the stress-strain state of the digital carrier panel antenna array mounted on the ship's match. Calculations are performed in the static case, when different types of pitching at a constant angular speed and variable angular speed. It is shown that the effect of roll has a significant influence on the stress-strain state of the panel, and its account at a variable angular velocity is a prerequisite for carrying out these calculations
Keywords: "carrier board, the pitching of the ship, the angular velocity, angular acceleration, stress, strain, statistics "
The relationship between the affective and cognitive components of attitudes in relation to a surrounding cultural landscape is investigated on a concrete example. The functions of distribution of perception level for cultural infrastructure are calculated on the basis of the experimental results obtained in May-June, 2015 by questioning among students of DonSTU. The emotional component was determined by technology of semantic differential. The primary data were processed in the nonlinear model developed within the catastrophe theory. The cognitive component was found by a technique of direct poll with the subsequent factorization by a classical method and allocation of key parameter. The difference in affective and cognitive perception of cultural infrastructure is discovered. At the group level the number of respondents which declared positive and strongly positive cognitive assessment are 10% more than for emotional one. With neutral perception, on the contrary, is 7% more on an affective indicator. In general on group the cognitive assessment is overestimated, the average level of emotional perception of infrastructure is 0,14 and cognitive is 0,27 (on a scale from -1 to +1). At the individual level these indicators among themselves practically don't correlate (Pearson's coefficient is 0,2).The received results say that the standard technique of direct poll at research of a cultural landscape is limited and it should be supplemented with the analysis of emotional perception. Such analysis for the considered audience is provided in work.
Keywords: cultural attitudes, affective component, cognitive component, questioning, semantic differential, nonlinear model, theory of accidents, function of distribution, perception assessment
The expert system for practical use by doctors in hospitals is designed The systems is solve the problem of classification opinions on the gestosis development and degree during pregnancy risk. Multi-factor knowledge base derived based on the results of studies analyzed in the work, and includes a set of genomic and post-genomic signs of pregnancy complications. The main users of the system (doctors, researchers and patients) and their requirements for software implementation of the developed expert system. Structure of expert decision support system in the evaluation of the risk of preeclampsia, comprising components (characterizing developed information systems belonging to the class of expert systems), the functions and subjects were created. The types, feature space feature descriptions and attributes the knowledge base of these patients. The generalized algorithm of the system and the possibility of its further development were given.
Keywords: Expert system, knowledge base, requirements analysis, Statistical classification, feature space, gestosis, preventive diagnostics, a personified medicine
The paper introduce modern information about localization of function of human cerebral cortex from the viewpoint of brain’s structure.
Keywords: brain, cerebral cortex, contex cerebi, neocortex, cytoarchitectonics, functional map of cere-bral cortex, localization of function of cerebral cortex, sensomotor centers
Synthesis of the TiO2 nanoparticles was carried out by sol-gel method. The optimal conditions for stable TiO2 gel obtaining was determined. The resulting samples were studied by IR spectroscopy. Studies have shown the presence of chemically and physically bounded water in TiO2 powders, dried at 125 ° C. Studying of the influence of the pH on the acid-base properties of the surface of the resulting TiO2 powders was performed by indicator method.
Keywords: TiO2 nanoparticles, sol-gel method, acid-base properties, indicator method, infrared spectroscopy, pH of the medium