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  • Determination of deflections of beams with corrugated web with the shear strain

    This article is devoted to the analytical determination of deflections of beams with corrugated web. The reduced shear modulus which must be considered when determining the components deflection from of the shear strain in the beam with corrugated web is defined. Applying the energy method in the form of the Ritz, the problem of determining deflections with considering of bending strain and shear strain is solved. This article, as an example, is considered simply supported beam on both sides of constant and variable cross-section and are given to the final formulas according with three kinds of loading. The results of the calculation of the numerical examples for the three main shapes of corrugated web are submitted. Numerical results with great accuracy are consistent with calculations based on the finite element method.

    Keywords: beams, corrugated web, energy, work, deflection, shear strain

  • 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

  • Algorithm of a «problem about transfer»

    The algorithm of a problem about transfer in a higher educational institution by results of Uniform Graduation Examination in view of various groups of introductory tests, priorities of receipt on a speciality,  the minimal lowest passing scores in subjects of groups of introductory tests and estimated figures of reception in high school is considered. The algorithm is realized on the basis of database Mirosoft Excel and programming language Visual Basic for Applications.

    Keywords: group of introductory tests, the candidate of transfer on a speciality, the applicant of transfer for a speciality

  • 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

  • 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.

  • New designs and technologies of files on the basis of application of solid coatings

    The article presents the new technologies and design tools for опиливания of machine parts. A number of new technical solutions in the field of innovative Metalworking tool for опиливания parts of machines, with a complex of technical and economic advantages over existing analogues. Shows the five variants of constructions and technologies for the production of files and надфилей, based on the use of hard coating. New tools are characterized by a low-cost, low labour-intensiveness of manufacturing and high performance.

    Keywords: tribology, the filing of a painful, spraying, carbide coatings, wear, self-sharpening, reversible cutting plates

  • Development of sensors based on ferroelectric films for hybrid sensor systems

      In this work researches of structural and electrophysical properties of ferroelectric films of lead zirconate titanate (PZT) which afterwards is planned to apply in hybrid sensor systems are done. Values of capacities of the received samples are in the range from 200 to 1100 pF, the range of thickness of the received films is 300-1000 nanometers. X-ray analysis showed direct dependence of the quantitative maintenance of crystalline PZT in film structure from partial pressure of oxygen in the camera. By results of research the range of polarization of samples are in the range 0,06 – 2,2 µC/cm2, and values of calculated piezoelectric modules are in the range 0,04*10-12 – 13,3*10-12 C/N.

    Keywords: sensors, segnetoelektric films, touch systems, piezoelectric modules.

  • A method of numerical modeling of spectrometric systems of gas sensors

      A principle of spectrometric systems of gas sensors was described. A model and a method of numerical modeling of spectrometric gas sensor with the combined radiator-receiver of infrared radiation on the basis of the punched semiconductor thermoresistor were proposed.

    Keywords: spectrometric gas sensor, model, method of modeling

  • Reducing energy consumption of household refrigerating appliances by intensifying the cooling condenser

    We propose a method for cooling the condenser compression refrigerator, including the use of melt water wetting the surface of the water condenser. The water is directed into the groove in the middle part of which is the tube condenser coil, and the water flows by gravity to the tribes of the inclined groove, wetting the surface of the trough and tube condenser. Remains of meltwater routed to the tank on the compressor.

    Keywords: Household refrigerating appliances, water, cooling, condenser, reducing energy consumption

  • The study of the dynamic characteristics Installations for jetting processing surface

      In this article the mathematical model dynamic process installations for blast cleaning the surface, and clearly showed the graph of the transition process, given the theoretical integer parameters yield in the specific process conditions.

    Keywords: Fluid Technology, a dynamic characteristic of the drive, nozzle - gate, jetting processing surface

  • Priority problem green building in Rostov-on-Don

    To create in Rostov-on-Don, ecologically effective, technologically advanced and durable green plantings to solve the problem: 1. Create a variety of trees for landscaping cities and towns; 2. Determine the principles of green plantings, ensuring their maximum environmental efficiency. In the steppe zone of Russia should use the structure of the park, with a high proportion of dense plantings (400 trees per hectare) of long-lived trees of the first magnitude.

    Keywords: green building, greening cities, assortment of trees, ecologically effective green plantings, the steppe zone

  • Micropower selective amplifier in basis in radiation-hard process technology ABMK_1_3

    Classical implementation of active selective amplifiers (SA) are usually associated with design sophisticated active elements (operational amplifiers) that consume relatively large power from their universality. This paper present the active SA based on an analog array chip ABMK_1_3, that have high level of radiation resistance to the flow of neutrons and accumulated dose of radiation. This SA implemented on the basis of a voltage-to-current converter with a minimum number of transistors and low consumption static current. Efficient use of current amplifier can be explained by use frequency dependent symmetric chains in a feedback loop. This property provides the independence of the pole frequency f0 = fp on the gain of the active element, as well as maximizing the quality factor.
    The basic analytical expressions that establish the relationships between the SA and the characteristics of active and passive components are given. The relations that help minimize sensitivity of parameters SA to instability properties of the components are considered. Simulation results of desired SA are shown.  

    Keywords: selective amplifier, bandpass filter, active RC-filter, analog array chip, radiation hardness

  • Multidiagnostics system for patients with postural deficits and algorithm for recognizing stabilographic signals

      Work is connected with the synthesis of information behavior of groups of autonomous intelligent agents of biomedical research, and machine learning methods to ensure the reliability of the forecast increase in their behavior using multi-agent systems based on the use of bionic principles, methods and models of swarm intelligence. Developed multi-agent system simulates the behavior of groups of autonomous intelligent agents developed methods to meet the proposed criteria of reliability, differing form the structure of the system and developed a set of specialized agents that provides the capability to model a group of biomedical robotics using autonomous intelligent agents. Classifier of stabilographic signals on the basis of Parzen method was developed. These data indicate that the auxiliary symptoms resulting from multidimensional scaling much more informative initial attributes.

    Keywords: Intelligent agent, multidiagnostics, Parzen classifier