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  • Principles of saving metal in reinforced concrete structures

    The question of economy of metal at production of building designs is considered. Measures for the organization of effective production in the current projects of high-rise and long-span buildings are proposed. Measures of increase of efficiency of construction are considered

    Keywords: organization of construction; economy of construction, production of building materials

  • Partial failure in the theory of reliability

    The concept of “partial failure” used in practice is analyzed as a state in which the possibility of continuing the operation of a technical device remains. It is argued that partial failures are widespread in the operation of technology, but unlike full failures, under which the continuation of work becomes impossible in any mode, not fully understood. A number of reliability indicators are proposed that take into account the specifics of partial failures and the possibility of continuing work when they occur. Attention is drawn to the fact that the decision to continue the operation of the device in the presence of a partial failure is associated with risks. The essence of the risks lies in the possibility of receiving damage in the form of further deterioration of the technical condition of the partially failed device. However, in many cases such a risk may be justified. The task of deciding on the continuation of the operation, in the conditions of a partial failure is a complex task of system analysis. Its solution will require the use of complex models compiled using modern methods of mathematical descriptions and research.

    Keywords: partial failure, reliability theory, reliability indicators with partial failure, risks of continued operation, making decisions on continuation of operation

  • The choice of an enclosing structure of a deep ditch in a zone of a transport tunnel at pointed building

    The modern problem of building of big cities consists that there is almost no place left for the free building. Therefore it is necessary to carry out so-called "pointed building" when construction is conducted in the constrained conditions. At the same time very often construction sites get to an area of coverage of the subway that causes particular difficulties at construction of constructions in deep ditches.

    Keywords: modeling, stress-strain, tunnel, subway, deep ditch, pointed building, ditch protection

  • The structure of epitaxial layers of narrow-gap solid solutions and compensation of defects

    The paper contains an analysis of the results of experiments on obtaining radiative structures based on gallium antimonide, formed by the method of thermal melt migration in a semiconductor matrix. The epitaxial process modes within the selected range were optimized for such parameters as the wavelength corresponding to the fundamental transition, a small lattice discrepancy, a small discrepancy in the coefficients of thermal expansion of the growing TP and the matrix. An original effect is described - an increase in the solubility of the Bi content in solid solutions, isoperiodic binary compounds A3B5 under conditions of a gradient temperature field. This effect allows a wide variation in the optical parameters of the element base of instruments based on solid solutions of GaSbBi / GaSb. The mechanisms of the generation of dislocations in a crystallized solid solution and the features of electrophysical and photoelectric parameters are analyzed. A structural solution of a light-emitting diode with strip geometry is proposed.

    Keywords: solid solutions, recrystallization, gradient liquid-phase epitaxy, thermomigration, indium antimonide-bismuthide, melt thickness, temperature gradient, components, growth coordinate, epitaxial layers

  • Physical properties of multicomponent narrow-gap solid solutions with mesostructure authors

    In this paper, the modeling of phase equilibria in multicomponent systems of A3B5 compounds was carried out and the compositions of the liquid phase equilibrated with a given solid solution were calculated. A model of excess thermodynamic functions is used, which takes into account the formation of associates in the melt near the solidus temperatures. The developed algorithm allows solving a direct problem (in which the input parameters are the growth temperature of the layers and the composition of the solid phase corresponding to the expected instrument characteristics) and the inverse problem (the growth temperature and composition of the solid solution are sought for the given liquid phase). The limiting concentrations of the alloying components, arsenic and bismuth, are determined. The structural and electrophysical characteristics of multicomponent semiconductor A3B5 heterosystems are discussed, the solid solutions of which crystallize from the liquid phase in a gradient thermal field. The mechanism for introducing impurities into the lattice of epitaxial layers of multicomponent solid solutions is described for the first time. With an increase in the thickness of the crystallizable film, the thermodynamically equilibrium substitution by antimony bismuth atoms is completed and the introduction of Bi atoms into the interstices takes place. The interaction of neighboring atoms with the valence electron shells of Bi becomes more symmetrical, which causes an increase in concentration. The concentration of film defects near its rear surface also increases. The obtained values of electrophysical parameters make it possible to draw a conclusion about the instrumental suitability of the materials under study.

    Keywords: solid solutions, mesostructure, antimonide, alloying, liquid phase, phase transformations, binary compounds, associates, lattice constant, multicomponent systems

  • Application of geoinformation systems in various directions during construction

    In the construction and use of software technologies, including roads, using GIS and CAD technology. We can also use technologies without data to work with attribute information. GIS is used to manage a large number of different-scale information on construction, reconstruction,etc.Any construction consists of several stages, including the construction of roads, starting, as we see from the planning, then the design and coordination of objects and putting it into operation. GIS during construction is considered in conjunction with all stages., at what first analyze the location of the object on the map. GIS in construction is one of the most important links in the overall planning system.

    Keywords: construction, geographic information systems, reconstruction,management, stages, planning, digitization, route, facilities, road

  • Factors of process quality of piggyback transportation

    The article discusses the application of the theory of qualimetry and product quality management for the creation and operation of piggyback transportation in Russia. Their implementation requires a comprehensive study of technical, technological, organizational, investment and legislative issues. The specificity of the provision of this transport service by rail in the regulatory aspect is shown. A multilevel system of factors influencing the quality of the process of railway piggyback transportation has been formed and substantiated. The first level factors that have the most significant impact include: personnel, materials, equipment, technology, organization and the external environment. These factors characterize the actions of production personnel, material support, the state of technical means and mechanisms, the technologies used, the managerial component, as well as the external environment in which piggyback transportation is carried out. Structural grouping of factors is presented in Ishikawa diagram. Three characteristics of the process quality of piggyback transportation are highlighted - safety, timeliness and cost effectiveness. The use of factors allows you to create a range of quality indicators and methods for their evaluation, as well as to develop measures to improve the quality of transport.

    Keywords: transport, piggyback, piggyback traffic, transport service, process quality, factor, Ishikawa diagram

  • Optimal physical parameters choice of ice melting in the contact network DC

    The physical process features at the point of contact of the electric rolling stock current collector and the contact wire in the system of traction power supply of DC Railways are considered. The choice of parameters of the combating icy frost formations on the wires of the contact network by melting ice method is justified

    Keywords: physical process, an electric arc, melting of ice, the estimated coefficients, the choice

  • Numerical simulation of laser annealing of a thin amorphous silicon film for solar cells

    Numerical modeling of the temperature distribution during heating (annealing) by a pulsed Nd: YAG laser of an amorphous silicon (a-Si) film on the surface of an AZO glass substrate is carried out. The simulation was performed on the basis of a numerical solution of the heat equation in the Matlab program to determine the energy density of the laser radiation necessary for crystallization of the a-Si film. For a wavelength of 1064 nm, it was obtained that the temperature at the surface of the a-Si film reaches a maximum value at a time point of 146 ns with a laser pulse with a Gaussian time-shape. It is shown that for the crystallization of an a-Si film with a thickness of about 800 nm with laser radiation with a nanosecond pulse duration, the optimum energy density is 600-700 mJ / cm2 when the temperature across the thickness of the a-Si film corresponds to 550-1250 ° C.

    Keywords: Numerical simulation, laser annealing, temperature distribution, a-Si film, solar cell

  • Numerical research and optimization of the shape of an axisymmetric body in an aerodynamic flow

    In this paper, a numerical study of the optimized body shape with minimal aerodynamic drag has been carried out. A computational experiment involves the transition from the study of a real object to the study of its mathematical model, for the study of such processes, a full-scale study of which is impossible, for some reason is difficult or expensive. The conditions for comparing the forms of bodies in a computational experiment are that they are kept constant for all bodies: the volume and shape of the working area; distances from sources, drains and centers of bodies; gas flow rates; body mass and other secondary characteristics besides just the very shape of the surface.

    Keywords: aerodynamic resistance, optimized body shape, numerical simulation, computational experiment, temperature field, convective heat transfer

  • Means of knowledge representation and data extraction for mining situations

    In this paper, an analysis of the problems and tasks arising from the design of situational awareness tools has been carried out. As a result, it has been established that the approaches in this area do not satisfy the requirements for modern intelligent tools for operational decision support for the reasons for the lack of methods and tools reflecting the dynamics of information processes and a distributed information processing architecture with weakly structured properties. The methods of operating and extracting knowledge from semistructured dynamic information are proposed.

    Keywords: Situational awareness, poorly structured data, temporal information, dynamic structures, intellectual analysis

  • Approaches to solving the problem of introducing the digital economy (including digital energy) in the Russian Federation

    The paper discusses the technological barriers arising from the transition to a digital economy, in particular in the housing sector. The technological barrier consists generally of three components. The first component is that the development of IT technologies requires the initial accumulation of a large amount of data. Metering devices for this task are not suitable due to their functional tasks. The second component is the lack of interest on the part of end users. The third component is information security. One approach to solving the problem is to apply and implement the BigData concept.

    Keywords: Semenistaya E.S., Leonova A.V.

  • Model of a dynamic neuron with state memory

    The problems of synthesis of a model of dynamic neuron with state memory (DNSM) are considered in the paper. The introduction of a special additional parameter into the model of a neuron, defined as a state parameter, is substantiated. It is indicated that the parameter of the state of the neuron has the ability to vary with time depending on the nature of the information processes that occur in neighboring neurons of the network. This parameter in a certain way accumulates information about the history of the behavior of the neuron in accordance with the entered formal descriptions. The concept of a "strained neuron" is introduced, taking into account the above. This concept characterizes the degree of influence of a given neuron on the neurons surrounding it. On the effects of time-varying parameters of the state of neurons, it is proposed to implement the process of self-evolution of the network directly during its operation. A variant of the analysis of the structure of the neural network, created on the basis of the proposed model DNSM. The topological representation of a neural network in the form of a graph model allows formalizing the interaction of neurons in a network with each other, both in time and in space. For this, the concept of k-space is introduced, which determines the degree of proximity of neurons to each other. The degree of proximity of neurons allows one to formalize, in the form of mathematical relationships, the procedure for the exchange of information between neighboring neurons in a network. Mathematical relationships that formalize these processes are given. A variant of the structure of the hardware design of DNSM, focused on implementation using FPGA technology, is proposed.

    Keywords: dynamic neuron with state memory, connectionist model, self-evolutionary mechanism

  • Numerical study of the propagation of nonlinear waves on the surface of a viscous liquid

    A nonlinear boundary value problem on the propagation of surface waves in a layer of viscous incompressible fluid of infinite depth is considered. Equations of motion and boundary conditions are written. The solution of the problem is found by the small parameter method. An expression for the damping decrement of the wave oscillations is obtained. The program code in C++ for the numerical study of the propagation of nonlinear waves on the surface of a viscous liquid is developed.

    Keywords: viscous liquid, slabowska fluid, nonlinear surface waves, the damping rate of waves, phase velocity, frequency wave

  • Modeling of temperature regulation system in the bioreactor for cultivation Chlorella microalgae

    The paper considers the bioreactor for cultivation of Chlorella microalgae. The indicators of the process quality and the description of the bioreactor design are given. The computation of the transfer function of the system to maintain the temperature of water in the main tank by the method of Rotach is calculated

    Keywords: automation, bioreactor, biotechnology, Chlorella, system of regulation, transfer function calculation, Rotach method