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  • 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

  • Optical refraction and model methods of taking into account its influence on the characteristics of the range-finding channel of the laser tracking locator

    Laser tracking locators have certain drawbacks, among which there is a strong influence of the atmosphere on their energy and precision parameters, the process of aiming a narrow beam at the object, etc. High requirements for locators (the error of measuring the range to a few centimeters) lead to the need to take into account the state of the atmosphere on the route for application Corrections in the measurements. In particular, the phenomenon of refraction leads to a significant distortion of the signal. To reduce the error of distance measurements it is advisable to use methods to compensate for the effect of refraction or to take it into account and use the correction coefficients. The article shows that the effective solution to this problem in the absence of the possibility of obtaining operational and accurate information about meteorological parameters is the use of parallel laser probing of the atmosphere. More promising in this case is the use of laser methods for controlling atmospheric parameters, which we described and experimentally investigated at the Chauda, ​​Feodosiya, and the Republic of Crimea provinces. The obtained atmospheric data were used to create a mobile laser-television locator for external-trajectory measurements of the descent of the aeroelastic systems "Kafa" and were installed both on the ground and on an air balloon. The trajectories of the descent of balloons and cargo parachute systems were studied.

    Keywords: Laser tracking locator, ranging channel, atmospheric effect, refraction, model compensation method, laser probing

  • Dispersion method of static and dynamic refraction accounting for the range-finding channel of the laser tracking locator

    Refraction has a strong influence on the accuracy parameters of the range-finding tract of laser tracking locators and the process of directing a narrow laser beam onto the object. High requirements for locators (the error of measuring the range to a few dozen centimeters) lead to the need to take refraction into account for making corrections to the measurements. Significant distortion of the signal leads not only to the phenomenon of static refraction, but also dynamic. To reduce the error of distance measurements it is advisable to use methods to compensate for the effect of static refraction or to take it into account and use the correction coefficients. The article shows that the most effective solution to the problem of refraction in the presence of a dynamic component is also the use of parallel laser probing of the atmosphere, but it must be carried out at two different wavelengths. In this case, the main method of calculating the correction factors is the dispersion method, which makes it possible to reduce the relative measurement error to 106. The use of laser methods for controlling atmospheric parameters, including two-wave and two-frequency ones, was described by us and experimentally investigated at the Chauda, ​​Feodosiya, and the Republic of Crimea fires on YAG: Nb3 + IZ-25 lasers and continuous lasers . The obtained atmospheric data on the LT-5Z laser were used to create a mobile laser-television locator for external-trajectory measurements of the descent of the aerial systems "Kafa +" and were installed both on the ground and on an air balloon. The flight trajectories of balloons and the descent of cargo parachute systems were studied.

    Keywords: Laser tracking locator, ranging channel, atmospheric effect, static refraction, dynamic refraction, dispersion compensation method, laser two-wave probing of the atmosphere

  • Mathematical modeling of refrigeration using vortex tubes in vegetable stores

    in the article the questions of modeling of thermal effects in vortex tubes with application software, for example, CFD-complex is Studied. Discusses the practical applications of thermal effect in vortex tubes, is proposed using the process of refrigeration in vortex tubes for climate control in vegetable stores with the aim of improving the safety of the products. This article is of interest to a wide circle of readers, dealing with issues of simulation software packages.

    Keywords: heat effect, cooling, heating, microclimate, modeling, CAD software program, 3D model. CFD-complex is Studied, FlowVision

  • Monitoring the thermal efficiency of a regenerative air heater rvp-54

    The article discusses the methodology of assessing the technical condition of the regenerative air heater RVP-54 on power boilers Naberezhnye Chelny CHP on the basis of the results of the monitoring of the thermal efficiency. In article the algorithm of monitoring and evaluation of the thermal efficiency of regenerative air heater, allows in real time to compare actual performance with previous values and to eliminate the revealed violations.

    Keywords: Naberezhnye Chelny CHP, energy boiler, regenerative air heater RVP-54, technical condition assessment, commissioning and configuration, thermal calculation, temperature difference, heating surface, thermal efficiency, heat losses

  • A numerical method for solving systems of linear algebraic equations based on the metric algorithm

    The article describes the problems of mathematical modeling of large systems. Scientific novelty of the work consists in the implementation of a new numerical method for solving systems of linear algebraic equations. This method is based on a targeted random search and stochastic calculations whith using of cloud technologies.

    Keywords: system of linear algebraic equations, cloud computing, self-organization, metric

  • "The study of the effect of vector random loads on beams "

    The transverse vibrations of the beams of a constant cross section are taken into account, taking into account the damping. We consider random oscillations of a beam under the action of vector kinematic and dynamic effects. The examples show the influence of correlation coefficients on the standard deviations of the cross sections of a beam. The internal forces in the form of bending moments and transverse forces are determined. An example of an action of a random process with a latent periodicity is given

    Keywords: Beam, damping, deflection, bending moment, shear force, random process, spectral matrix, correlation, vector, matrix, transfer function

  • The functional structure's connection of facilities for disabled people with a stepped system of cultural and consumer services

    The interrelation of pedestrian accessibility of facilities for disabled people with the functional composition of these facilities is considered, a methodology for formalizing such a relationship

    Keywords: architectural typology, invalids, pedestrian accessibility, objects of specialized services, stepped system of service

  • Brightness control in computer graphics: nonlinear aspect

    The ability to change brightness contrast of images with the help of some graphic packages’ tool is studied. In parallel the influence of this tool on hue and saturation of forming the image pixels is investigated. It is shown that tool as a whole is of little use for brightness contrast informative control, because in a number of packages it cannot provide brightness contrast gain, in others - does not keep hue and in all - deforms a saturation that threatens with loss of the graphic information transferred by saturation contrasts. Corresponding artifacts are considered and discussed.

    Keywords: nonlinear brightness control, brightness contrast, colour hue and saturation, graphic information integrity, artifacts

  • Design features of the new regulating valves straight-through type

    Regulating the flow of liquids in pipe systems is carried out by different types of control valves. In the petroleum and chemical industries the most widely regulating valves straight-through type. However, in many constructions of valves of this type the problem of cavitation is not resolved completely. With the aim of reducing the negative impact of cavitation on the valve body and pipeline the authors have proposed and developed new designs of valves uniflow type organization of the fluid flow in internal cavities which helps to reduce cavitation effects.

    Keywords: transportation, fluid valve, regulating, cavitation, flow, valves

  • Methodology for conducting field experimental studies on the landslide slopes and road designs on them using vibro-measuring complex

    The method of in situ experimental studies on the landslide slopes and road designs on them using vibro-measuring complex

    Keywords: The landslide slope, experiment, microseismic vibrations, monitoring of dynamic deformation, vibrometry, model

  • Computer modelling of X-ray images obtained with mobile customs inspection systems

    The algorithm for computer simulation of x-ray images of mobile inspection systems is considered. Educational software which implements this algorithm is described. The goal is to develop the software that not only allows to view the final x-ray image but to design complex scene of 3d objects in interactive way and then use it to render the x-ray projection. The parameters required for precise and realistic x-ray image simulation are considered. They are the objects geometry and position, size and position of the detector and radiation source, the beam energy and other characteristics. Next, the algorithm and formulas for projection of 3D object onto detectors pane are given. Then, the algorithm for calculation of pixel color in greyscale is provided. It is based on traditional ray tracing algorithms like z-buffer used in computer graphics. The input data is the scene of complex 3D objects designed with built-in 3D editor in stereolithographic format. The file in stereolithographic format is used both to store the scene geometry and the characteristics of materials associated to its objects. The distance traveled by the beam inside the object is calculated using the ordered list of the mesh nodes of the object. As the basis of this algorithm is the law of attenuation for X-rays the attenuation coefficients stored in database are also used. Finally the picture of example 3D scene with hidden prohibited goods and rendered x-ray image with these goods visible are provided.

    Keywords: computer modelling, computer graphics, computeraided drawing, x-ray, ray tracing, cargo control, stereolithography

  • Stiff problem with the exponential nonlinearity for testing of mathematical modeling systems and circuit simulators

    The improvement of methods of electronic devices simulation is currently ongoing, so development the tests for these methods is the actual task at the present time. The goal of this paper is to develop the original test problem for efficiency assessment of numerical methods of ordinary differential equations solving and methods of numerical analysis of transients in electronic circuits and systems. The test problem is presented as mathematical model and electronic circuit too. Test problem and technique of estimation of numerical analysis algorithms’ accuracy proposed in the present paper can be used in circuit simulators and in computer mathematics programs to test both known and new simulation methods for electronic circuits and systems with various dynamics, including stiff and/or nonlinear circuits.

    Keywords: numerical methods, electronic circuits, transient analysis, ordinary differential equations, stiff systems

  • Multilayer 1d-periodic absorbing structures in the optical range

    In the present work a new trends in the development of absorbent materials are described. The results of calculation of scattering and reflection patterns for multilayer structures are presented. Parameters of the structures with highest absorption are evaluated. Analysis of obtained theoretical calculations is presented.

    Keywords: resonance absorption, metamaterials, plasmons, nanophotonics, nanostructures, reflectance

  • Algorithm and its program realization to control the hue contrast of digital images

    Graphic information carried by hue contrast is actualized, mathematical description specificity of hue as the basic colour characteristic is investigated, theoretical bases of hue contrast control are stated, original algorithm and program for images hue contrast control are described, resolution of the offered method is experimentally estimated, scope of the created software product possible applications is outlined, efficiency of its application in expert problems is shown.

    Keywords: graphic information, hue contrast, contrast control, algorithm and program realization, latent images