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  • Mathematical methods for bearings of unmanned aerial vehicles identification in a group

    The questions of mathematical interpretation of results of trajectory measurements are discussed in terms of increasing the accuracy of identification of bearings of unmanned aerial vehicles during their movement in a "swarm" - a group. Variants of identification of horizontal and spatial bearings are offered. For each of the variants, criteria are proposed for identifying the belonging of the measured values ​​to the same object in the group and the conditions for achieving them. The situation of false positives is shown. It is determined that additional identification measures are needed to eliminate false bearing triads and uncovered ambiguities, including the use of combinatorial exhaustive search algorithms. For their study, it is necessary to develop an experimental statistical model with an algorithmic description of cause-effect relationships, which is a further development of this work.

    Keywords: " unmanned aerial vehicle, group of objects, bearing identification, horizontal bearing, spatial bearing, identification criteria, false notch"

  • Full-scale studies of the noise characteristics of the transport stream with a directional microphone

    The constructions of directional microphones of the "linear" type and the test procedure are described. On a controlled lane of the highway, full-scale studies of microphones produced by the authors were carried out. Thus, the relative error in the measurement of microphones No. 1 and 2 was found, which was 12.1 and 13%, respectively. The minimum error is detected with a microphone of the "linear" type No. 1, whose slots are located on the sides on four sides

    Keywords: transport stream, transport noise, passive acoustic detector, directional microphone

  • Repair of the bridge superstructures using alkilalkoksisilanovoy mixture and polymer fibers

    Repair of the bridge superstructures made to restore the performance of the facilities from damage incurred during operation. The main technical measures to improve the durability of structures buildings are reconstruction work on the prevention of water penetration from the roadway construction on the underlying design of superstructures and supports. Repair badly damaged sections of shelves extreme beams of the superstructure shall be mopping up indicators of acidity of not less than pH> 12 (concrete), followed by reduction of the dimensions of the concrete B30; F300 (in Spanish hlor.solyah.); W8 with pre-staging of additional rebar epoxy glue. Repair surface defects superstructures beams includes: To prepare and clean the defective concrete surfaces slabs beams superstructures sandblasting method, a chemical cleaning of the valve; Repair of surface defects of slabs beams non-shrink fast-hardening dry mix containing polymer fiber EMACO®90 and EMACO ®S88C; To restore the protective layer thickness of 20 to 40 mm is provided the use of a repair composition EMACO®S88S. For hydrophobic facades superstructures, attachments, etc. used water repellent water-based to protect concrete surfaces, which is designed for use on old and new concrete surfaces of bridges MASTERSEAL®303V.

    Keywords: repair; concrete bridge; superstructures; fittings; waterproofing; anti-corrosion coating; MASTERSEAL; EMACO

  • Analysis of factors affecting the wear resistance of asphalt concrete

    In the article the results of the analysis of the main factors affecting the wear mechanism of asphalt concrete pavements are given attention to the properties of the stone material and the binder. The questions of the influence of dust formed as a result of deterioration of coatings on the environment are considered.

    Keywords: asphaltic concrete, road surface, environment, wear products, wear resistance, wear factors

  • Teploognezashchitnye composition cement mortar on the basis of the distended vermiculite and the pumice

    Are represented the results of studies on the development of teploognezashchitnykh composition cement solution mixtures on the distended vermiculite and the pumice with the application of a multifunctional additive D -5. Are proposed the compositions of teploognezashchitnykh composition mortars, which make it possible to substantially improve the physicomechanical properties of solution mixtures and solution. The introduction of multifunctional additive D -5 to solution mixtures makes it possible to improve the properties of composition solution mixtures and to improve the characteristics of solution. The replacement of the fine dispersed fraction of the distended vermiculite d0,63 mm does not produce by pumice by the volume in the solution mixtures a noticeable increase in solution density, in this case their strength characteristics grow. The developed composition solution mixtures correspond to requirements ALL-UNION STATE STAN. 28013–98 and have low prime cost due to the use of the pumice

    Keywords: portland cement, the distended vermiculite, pumice, additive D -5, teploognezashchitnyy composition solution, transverse strength and compression, the mobility of mixture, exfoliation property, the density

  • Deformable flat supporting parts of bridges

    In this article we consider correspondence problem of the supporting parts containing deformable polymers used in the beam bridges (used in bridge constructing - лишнее, мне кажется). According to the shear diagram, supporting parts shall provide free angular and linear displacements of the beams' end faces sections. Otherwise gradual destruction of the nearby areas is possible. We study a rubber supporting part (RSP). Factors contributing to the deformation of the supporting part and their calculation with different algorithms, including the differential equation of the curved axis and Mohr method are given. The values of angular and linear deformations for the concrete reinforced bridge beam are calculated.

    Keywords: bearing, adjustable bearing, deformation, bridges, bridge beam, shear strains, angular displacement, linear displacement, crumple.

  • Interdisciplinary foundations of the development concept for the city transport system (based on the transport sections of the Yekaterinburg Master Plan project for the period up to 2025)

    The article is devoted to the topic of interdisciplinary balance in the solution of problems of the urban transport systems development. On the example of the concept of the transport system in Yekaterinburg development, the authors suggest ways of introducing interdisciplinary research: the author's multi-criteria system for assessing the transport system is proposed. The introductory part of the article is devoted to the formulation of the main goals and tasks of the development of transport systems in the Russian city. When considering the transport system in Yekaterinburg, it is proposed to use the zoning of the city's territory to formulate strategies for its development, taking into account local conditions. Also, the authors propose to take into account at the project level various international trends in the development of transport systems.

    Keywords: transport systems, master plan, urban planning, interdisciplinary research

  • Analysis of the physical processes occurring in the lubricating layer of gas-dynamic bearings

    Examples of bearings with hydrodynamic wedge are mapped to specific features of the incompressible lubrication (drip liquid) and compressible (gas). Due to the physical nature of the processes occurring in the gas lubricating layer. The main advantages of axial and radial gas dynamic bearing with spiral mikrokanale, which was the most widely and effective used not only as bearings, but also as the best contactless seal.

    Keywords: lubrication layer, hydrodynamic wedge, pressure, load capacity, helical grooves, optimal parameters

  • “Rozmysly” public open engineering forum of scientific and technological activities, social and technological entrepreneurship

    The project for creation of the first in Russia Engineering Forum of scientific and technological activities, social and technological entrepreneurship “Rozmysly” is presented, this forum develops the principles of an open public interdisciplinary electronic environment. The substantiation of the social significance of the project is given. The new project implies involving an even wider range of practitioners, research engineers, young scientists, applicants, graduate students, students and even senior pupils in scientific engineering knowledge by providing them with the opportunity to publish, read and discuss the results of promising research and development works, engineering solutions, inventions and rationalization or innovative proposals in the form of an electronic preprint. Conceptually, the project represents a new culture of scientific publications based on global and mini Internet platforms. It is shown that the basic advantage is achieved through the implementation of an open access initiative. From the date of publication, the material is available for the widest possible range of readers. The project is a kind of an interdisciplinary scientific and technological engineering forum.

    Keywords: site, Internet platform, engineering forum and storage, open access, preprint, foresight

  • Two-dimensional model of the distribution of the magnetic field between erythrocytes in a narrow capillary

    The article deals with the movement of erythrocytes along the narrow capillaries with a diameter smaller than the erythrocyte diameter. Red blood cell in narrow capillary has tank-treading motion. The erythrocyte rotation frequency reaches several dozen revolutions per second. Electric charges located on the surface of the erythrocyte, move together with the erythrocyte membrane and create a magnetic field in the surrounding space. A two-dimensional model of erythrocyte movement along narrow capillaries was constructed. If the erythrocyte surface area and erythrocyte charge are known, then the density of charges on the erythrocyte membrane can be determined. The magnetic field strength of a moving charged particle can be determined if the particle charge, the particle velocity, the distance from the particle to the point at which the magnetic field strength is determined, the angle between the direction of the particle velocity and the direct connecting particle, and the point at which the tension is determined are known. The total strength of the magnetic field of several moving charged particles is defined as the vector sum of the magnetic field strengths of the individual moving charged particles. In the two-dimensional model it is assumed that the red blood cells are rectangles that move along the capillary, and the erythrocyte membrane is the sides of the rectangle. Discrete charges are located on the sides of the rectangle and move either clockwise or counterclockwise. It is possible two variants. Their membranes either rotate in the same direction or in opposite directions. Calculations were carried out for both variants and at different rates of rotation of erythrocyte membranes (from 0 to 50 revolutions per second) and distances between red blood cells. It is shown that at distances between erythrocytes smaller than the two capillary diameters, the influence of neighboring red blood cells can be neglected (the difference is less than 3%).

    Keywords: "mathematical model, magnetic field, erythrocytes, narrow capillaries, magnetic field strength "

  • Progressive construction technologies in cramped conditions of urban areas

    Modern urban development policy pays special attention to the application of new and well-known technologies in the development of underground spaces of historically developed urban areas. Rational use of urban areas occurs up and down, without expanding the boundaries of urban areas. Technology "slurry wall" in the development of underground space continues to rapidly gain popularity. The use of this method allows to solve the problem of construction in cramped conditions and is one of the most popular in modern urban development practice

    Keywords: rational use of urban underground space, advanced construction technologies in cramped conditions

  • The estimation of exploitation technological efficienПитухин А.В., Шиловский В.Н., Скобцов И.Г., Киселев С.А.

    The paper deals with the investigation of exploitation technological efficiency of metall-cutting machine tools. The main goal of this study is to determine more advanced way of choice of equipment and to organize metall-cutting machine tools rational maintenance. Classification of basic and optional evaluative measures is presented in the first part of the paper. The research methodology provides the estimation of exploitation technological efficiency by calculation of the complex evaluative measure. The results of comparative estimation of two metall-cutting machine tools (Okuma LB 4000 EX, CTX Gamma 2000) are presented in the last part of the paper. According to evaluation result, Okuma LB 4000 EX stands at a higher level of exploitation technological efficiency.

    Keywords: exploitation technological efficiency, comparative estimation, complex evaluative measure, methodology, data analysis

  • The theory of step support of sliding with the incompressible and compressed lubricant

    On the basis of Reynolds's equations for thin layers of viscous Newtonian liquid laws of distribution of pressure are found in the incompressible and compressed bearing layers of a step support. For achievement of physically clearer comparison of lubricant properties and the bearing ability of two different lubricant environments the flat model of a step support is used. The algorithms of calculation of carrying power and rigidity of both lubricant layers allowing to pass to statement and the solution of problems of optimization of dimensionless geometrical parameters and comparative integrated characteristics of hydrodynamic and gasdynamic step support of sliding are received.

    Keywords: lubricant layer, viscosity, pressure, density, Reynolds's equations, splines, Petrov's number

  • Process perfection for searching inefficient SQL-requests in the Oracle

    Introduction: The paper discusses methods to solve the problem of searching inactive queries for Oracle Databases in example . If there are no clear reasons for Deterioration of performance, database managers need to analyze very large amounts of statistical information provided by database management. The aim of study: to visualize the information, it is proposed to perform initial intellectual analysis the formation of a parameters model for the query to classify and Separate set of requests. Scope of work . Each query is described by three sets of parameters: specified query execution plan parameters, real implementation plan parameters, and the characteristics of the implementation environment. its consider according to the characteristics, purpose and importance of each set of parameters and the methods to get them .its depends of selection the parameters to use in SQL query model ,query execution conditions and data base settings (DBS). Moreover, its depends on fails in the nature of the system for client programs. Problem statements. The problem is formulated by the dynamic formation in the inactive SQL query model from some of sets parameters that already contained identifiers. Conclusion: The proposed of this approach will speed up the search for inactive queries and can be extended to others databases, with consider their characteristics.

    Keywords: SQL, query, DBMS, Oracle, inefficient SQL query, grouping, clustering

  • Broadband attenuator with electronic control

    In article a modelling and experimental survey of the controlled attenuator in a frequency range 2 - 4 GHz is performed. It is received the minimum attenuation no more than 3.5 dB, the maximum attenuation not less than 56 dB at a current 3.8 mA. The amplitude-frequency characteristic unevenness at a current 3.8 mA does not exceed 3 dB. The attenuator design is made in the form of the hybrid module. The attenuator is intended for adjustment of transfer constant of the microwave receiver.

    Keywords: attenuator, pin-diode, amplitude-frequency characteristic, control current