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  • Modelling of rods with defects with different types of fastening

    The task of identification of defects in rods with different variants of fastening. In the basis of lies method parameter identification based on an analysis of the frequencies and parameters of natural modes of the structure. Built model of the rod design has defects fluctuations, using finite element of the complex 

    Keywords: Defect, damage, rod, the oscillations of the cantilever rod

  • The studying of oscillations of the corpulent cantilever rod model with a defect

    Defined criteria for identification of defect parameters, on the basis of the analysis of the different modes of own fluctuations, with the use of finite element modal calculation console corpulent model of a rod with a single defect. Developed finite element model of a universal complex . Considered corpulent (3-d) model on the basis of 3D finite element Solid92. When solving the problem considered on 26 oscillation modes depending on the size of the defect and its location.

    Keywords: Damaged, defective, swing, cantilever, frequency

  • Consensus Protocol in Asynchronous Networks with Failures

    Consensus problem involves a system of processes, some of which may be faulty. A fundamental problem of fault-tolerant distributed computing is for the reliable processes to reach a agreement on a same decision. One approach to achieving such agreement is for processes to vote and agree on the majority value. In the absence of faults, this works fine, but the vote even one faulty process can swing the outcome. In this paper we present some result of analysis of a mixed-failure model, where t processes may fail, b out of which is the Byzantine failures and remaining c is crash processes. In a asynchronous model of computation for several distributed problems it turns out that a collection of N processes can tolerate c crash failures if 2c < N, while robustness against b Byzantine failures requires 3b < N. Our algorithm rely on a weak definition of the Byzantine failures which disallows them act as a dead or a crash processes and can tolerate the 2(N – 2c)/3 failures.

    Keywords: fault tolerance, distributed algorithms, asynchronous networks, byzantine failures

  • Microwave band-pass filter on waveguides of complex cross-section, integrated into a multilayered chip with SIW technology

    The possibilities of waveguide elements realization in the structure of multilayered integrated chips of centimeter and millimeter ranges with SIW (Substrate Integrated Waveguide)-technology application are considered. The approaches allowing effectively using in new structures the algorithms and techniques of the electrodynamic analysis and synthesis of passive devices on classical all-metal waveguides are offered. Advantages of use in SIW structure the waveguides of complex cross-section are considered on the example of the microwave band-pass filter.

    Keywords: A.A. Gadzieva, V.V. Zemlyakov, S.V. Krutiev

  • Analytical and experimental studies to determine the effective temperature difference of heat exchange boreholes with coaxial collector

    The results of the heat transfer processes studies in the heat exchange borehole (BHE), equipped with coaxial collector in order to establish the influence of its design parameters, the properties of the rock mass, mode and duration of the coolant flow to the effective temperature difference. The resulting analytical equation for the effective temperature difference in the conditions of unsteady heat transfer experimentally verified in a lab BHE and can be used in the design of these BHE systems in specific geological and technical conditions. Use the resulting equation for the inverse calculation can be counted the diameter and the depth of the BHE, as well as the duration of the coolant circulation in the coaxial collector. The advantage of such approach is the consideration of the main factors that influence the of the effective temperature difference.

    Keywords: borehole heat exchanger (BHE), effective temperature difference, coaxial collector, heat pump, low-potential energy

  • Improvement of methods for extending the life cycle of the technical condition of long-exploited water conveyance facilities

    In this article the basic parameters required for residual life assessment and life extension of the technical condition of water or long operated facilities. Inlet water or prolonged use many facilities design elements out of order it - complete destruction of concrete structures water conveyance structures, the formation of defects, normal operational performance of the design water conveyance facilities, such as violation of butt joints, as well as the destruction of the individual elements of the structure, etc. During the development of methods for extending the life cycle of water conveyance structures are obtained by the use of impervious geotextile cover that make for a correct evaluation of residual life of structures may extend its operational life cycle. The question arises of the need for correct and timely manner and to assess the remaining amount of the carrying capacity of water conveyance structures, to evaluate the technical condition and extend its life cycle. To do this, we can apply the proposed impervious geotextile cover. 

    Keywords: hydraulic structures, water-conducting structures, life cycle, residual life, technical condition

  • Winter concreting technology with flexible heating elements

    The article discusses the use of surface mats for thermoelectric heat treatment of concrete in the winter and complex additives. At the same destructive processes in the material does not occur and reduced thermal treatment.

    Keywords: сoncrete thermoelectric mats complex chemical additives, heat treatment

  • Raman spectra on three phase transitions of perchlorate of natrium

    The analysis of temperature dependence of frequencies of lines  is conducted active in the spectrums of combination dispersion of  perchlorate of natrium. The theory analysis of spectrums is conducted.

    Keywords: Perchlorat of natrium, anion, spectrums of combination dispersion, phase change

  • Flexible piezocomposites with mixed connectivity phases in the system

      Laboratory technology was developed to fabricate flexible piezocomposites with ferroelectric phase - polymers having signal reception factorv • gv 5000 • 10-15 m2 / N. The values of the given coefficient were achieved by switching from a probabilistic (spontaneous) percolation to a correlated one in the process of forming material. This made the production of 0-1–3 piezocomposites, in which a part of piezophase has 0 connectivity, and the other part – 1 connectivity possible. To improve the efficiency of piezocomposite polarization before their manufacturing the surface of piezophase particles, which were obtained by the partial destruction of the porous frameworks, was treated with coupling agent, which did not only improve the polymer adhesion to piezophase, but also allowed the removal of water from the particle surface. The latter effect reduced the value of interfacial conductivity, i.e. prevented the voltage drop of the polarizing field. Matching of polymer conductivity and piezoceramic particles by determining the optimal polarization temperature was carried out as well.  

    Keywords: piezocomposites, percolation, connectivity, electrophysical properties

  • Nonfinancial financing of construction sector entities: Theory

    Credit availability to construction sector entities determines for thin-capitalized construction firms the possibility of survival during the crisis and of efficient growth during the economic recovery. The main lenders for construction sector entities are commercial creditors (suppliers) and banks. Although their credit policies are similar, debt to commercial creditors dominate in the balance sheets of borrowers, because of customary business practices in construction industry and regulatory distinctions.

    Keywords: information asymmetry, agency theory, trade credit

  • An algorithm for finding the linear functional quality of complex technical systems with varying degrees of competence of experts.

    This article describes an algorithm for finding the linear functional quality that describes the order of preference on a set of technical systems. The basic idea, which implements the algorithm is to break the complex solutions of the preference (for many variables) into a number of simple solutions (in pairs of variables), followed by a formal synthesis of the overall solution.

    Keywords: The algorithm for finding the linear functional quality of the order of preference on a set of technical systems, formal synthesis, the numerical value of the degree of competence of the individual experts

  • Monitoring and evaluation of the strength of concrete at the plants of precast and ready-mix concrete

    Provides a method of representation of the scheme of control and evaluation of concrete strength at the factory. The method does not require detailed text-th maintenance, differs with visibility and convenient for workers of the construction laboratories.

    Keywords: Сontrol of the selling of concrete strength, the party of commodity concrete mixture, the party of the precast concrete and reinforced concrete, the required concrete strength

  • Capital structure determinants of construction companies

    This paper presents key capital structure determinants of construction companies and their impact on fund raising and financing mix formation in accordance with the conditions of construction activity. It was found that profitability and tangibility have a positive effect on leverage, risk - the negative and the effect of company size, assets growth rate and taxes is ambiguous.

    Keywords: capital structure determinants, profitability, risk, taxes, tangibility, construction companies

  • A hybrid evolutionary algorithm for solving linear systems of equations describing the circuits

    The article describes the main problems of circuit simulation. The problem of solving ill-conditioned systems of linear algebraic equations (SLAE) of large dimension. The modified algorithm is a linear algebraic solutions. Described a hybrid evolutionary algorithm for solving linear systems based on the proposed modified method. The results of the pilot study and comparison of the algorithm with the algorithms based on the traditional methods for solving linear algebraic equation, which confirm the advantages of the hybrid evolutionary algorithm.

    Keywords: Genetic operators, evolutionary algorithm, the system of linear algebraic equations, computer-aided design.

  • Methods of forming the technical and economic indexes of reconstruction program

    The article describes the methods of forming the program of technical and economic feasibility of reconstruction. The program is based on the technical and economic calculations which justify the need for its development. It is important to take into account the technical and economic indices which provide a minimal amount of construction works. During the development of technical and economic parameters, it is necessary to take into account the organization of construction, the terms of energy saving, heating, water supply, drainage and industrial waste water, human resources, the environment, the effectiveness of capital investments. All questions are considered for the perspective of the development of science and technology.

    Keywords: site renovation, technical-and-economic indexes