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  • Comparative study of the catalytic activity Pt/C and PtхNi/C materials in the oxygen electroreduction

    The catalytic activity of Pt/C and PtxNi/C electrocatalysts prepared by  borohydride methode was studed. It was established that the specific activity  of fresh prepared Pt3,7Ni/C  catalyst  in oxygen  electroreduction  reaction is higher in compare with Pt/C material. After treatment of Pt3,7Ni/C material in the hot acid  nickel in the surface layers of nanoparticles was dissolved and the composition of nanoparticles was changed to Pt5,6Ni. The electrochemical surface area of the Pt5,6Ni catalyst and specific activity was slightly decreased after corrosion treatment. 

    Keywords: platinum electrocatalysts, corrosion stability of the nanoparticles, fuel cells, X-ray diffraction, borohydride synthesis

  • Development of a universal database structure and properties of chemical compounds to build models "structure-property" based on heuristic algorithms

    The problems of building the architecture and design of the database structure for the storage of the structure of the chemical compounds and their analysis using heuristic algorithms
    Proposed the structure of the database that allows you to store information about the structure of chemical compounds with varying degrees of detail. This approach simplifies forming of the structural descriptors used to build models of "structure-property" based on the genetic algorithms.

    Keywords: database architecture, chemicals, data mining, heuristics

  • Evaluating the effectiveness of building software for sonar information systems, using a configurable software framework

    This paper examines the effectiveness of the software framework developed by the authors for the task of  sonar information systems software design. This is done by a theoretical estimate based on the data obtained during the actual production process, as well as practical by rebuilding the software using the skeleton. Fixed a set of indicators on which to judge the complexity and evaluated there . Finally, an assessment of the results of the experiment and draw conclusions about the direction of further research.

    Keywords: software design, sonar information systems framework, performance evaluation

  • Evolutionary approach to modeling of the distribution processes

    Considered the proposed approach to the allocation of resource flows. The approach developed on the basis of the method of bee colonies. Experimentally determined the dependence of the error of the algorithm of the problem dimension. Shows the dependence of the distribution of resources from a number of iterations, and the power of the swarm, and dynamics approximation of the distribution to the optimum.

    Keywords: optimization, distribution, collective adaptation, evolution, the error of the algorithm

  • Algebraic Analysis of Cryptographic Security Systems

    The research of algebraic cryptanalysis method was carried out in this work. Systems of the equations for tables of various sizes of nonlinear transformations of substitution for simplified model of GOST28147-89 algorithm are received, also we solve a one of this systems by a XL method. During this work we produced a program, which has realised a generation and solving of system of equations describing nonlinear transformations of substitution. We analysed a nonlinear systems of equations and calculated a value of complexity of XL method for eight blocks of substitution.

    Keywords: Algebraic cryptanalysis, XL method, nonlinear transformations of substitution, linearization nonlinear systems, Gauss elimination method, a cryptographic key, GOST28147-89 encryption algorithm

  • UV photodetector based on nanorods and zinc oxide films

    With the use of pulsed laser deposition and carbothermal synthesis а photosensitive structure on the basis of the Schottky barrier Au/ZnO(nanorods)/ZnO(film)/ZnO(nanorods)/Au was obtained. The parameters of the carbothermal method of synthesis of nanorods ZnO were optimized. Under directly applied bias of 7V current sensitivity of luminous flux for this photodetector is observed in the UV and visible regions of the spectrum, and is 0.14 A/W - for 325 nm and 0.18 A/W - to 405 nm, which means that this structure has the ability of potential applications in various fields for the control of UV radiation (for example, for the monitoring of solar UV radiation, control of UV radiation in air and disinfecting water devices).

    Keywords: ZnO nanorods, Schottky barrier, photodetector, photosensitivity

  • Catalyst-free thermal synthesis of ZNO nanocrystals from zinc vapor by low temperature

    ZnO nanorod arrays have been synthesized on silicon wafers by chemical vapor deposition (CVD) technique with different  temperature modes, without metal catalyst.  With this method   vertically aligned ZnO nanostructures  were grown at the quite low temperatures.  Modification of the method allowed to place silicon substrates in areas with different  ratios of concentrations of the molecules in the vapor phase. Photoluminescence spectroscopy and electron microscopy studies have shown that morphologies and optical properties of nanorods depends on different ratios of concentrations of the molecules in the vapor phase.

    Keywords: ZnO nanorods,chemical vapor deposition (CVD), photoluminescence

  • Pulsed laser deposition of ZnO nanostructures

    The arrays of ZnO nanorods were obtained on the sapphire substrates by means of pulsed laser deposition under the high pressure of argon. The conditions of synthesis were optimized, and their influence on the morphology of  ZnO nanostructures were revealed. It is shown that the concentration of oxygen vacancies in ZnO nanorods can be changed by regulation of the synthesis temperature from 850 to 915 °. This process can be controlled by the ratio of intensities of the photoluminescence emission in the visible and ultraviolet regions. So, it allows to create nanostructures for UV photodetectors or chemosensors depending on the temperature choice.

    Keywords: ZnO nanorods, laser deposition, PLD, photoluminescence

  • Processing of spatial information about the boundaries of sanitary zones of waste landfills on the basis of fuzzy logic

    The method of application of fuzzy logic to solve the problem of spatial planning using geographic and information systems is described. The spatial arrangement of objects on the map is used as input factors of the solution, to find which a model of the spatial descriptions of objects using a bitmap representation is constructed. The way of formalizing fuzzy judgments about positional relationship of objects and the system of inference making based on the fuzzy logic methods is developed. An example of using the method described in this article to determine the sanitary protection zone of industrial waste landfill in the territory of the Republic of Bashkortostan is given

    Keywords: fuzzy logic, geographic information systems, the problem of territorial planning, disposal of industrial waste, protection zones

  • The method of constructing a hierarchy of criteria on the basis of ontological analysis system

    The paper describes a method to build Jerah krietriev for solving decision making in the management of complex multivariable systems based on functional decomposition . The result of functional decomposition takes the form of an ontology -based posnroennoy deskriptinvyh logic to build a hierarchy of concepts. The advantage of this method is the ability to use it for semi-structured systems. The result of the ontological analysis of the functional structure of the system is the taxonomy, including a description of the processes , organizational structures, and indicators of quality of running processes . When referring to this ontology by using the proposed request is generated hierarchy of indicators , based on the processing of values ​​is carried out and decisions .

    Keywords: ontological analysis, systems analysis, ontology, descriptive logic

  • About research of the onboard integrated control system by aircraft with correction of coordinates

    The work is devoted to the study of algorithms of control subsystem as part of the integrated onboard control system of the aircraft and used in the final part of the trajectory. Algorithms of control subsystems are synthesized on the basis of the theory of optimized delta-transformations of the second order using the principle of the inverted pendulum on a cart. The studies based on the simulation using the developed software model, allowed to estimate as the impact dispersion, and the contribution to it of various subsystems.

    Keywords: terminal control, aircraft, on-board integrated control system, optimized delta transformation of the second order, autonomous short range radionavigation system, simulation, software model

  • Technology works with increased soil ground water retaining structures

    In this paper the technology of repair of ground water retaining structures soil mixture improved quality with and without soil mixture install.Use soil mixture , improved sharps and ensure the return of ashes (repaired ) slopes and ridge structures of high strength (up to 13-15 MPa) and water resistance , thus increasing the effectiveness and quality of the repair work and increased resistance to the elements of the structures induced defect . The presence of the bran soil mixture not only enhances the strength of 30-40% , but also gives a significant increase in water and frost (20-30 %), which prevent or substantially reduce the infiltration of water through the filtration body water retaining structures , since high strength and frost soil-concrete being laid on a slope ( in the recovery slope failure ) and groove (at soil dumping and capacity to or in excess of the design marks ) will reliably protect the body of the dams ( dams ) of the drawdown , erosion , buckling , suffusion , and other deformities.

    Keywords: technology, dribble feed , soil mixture, sift, cement, fly ash, dam, construction and repair operations, soil mixture installation, factors plan of the experiment, the regression equation

  • Comparative analysis of the syntactic parsers organization

    The article describes peculiarities of modern syntax parser systems and problems originating in text analysis. As a result of comparative analysis the authors propose a unified approach to processing of unstructured texts in Russian and English which combines morphology and syntax processing. The developed syntax analysis system, using verbs’ valency dictionary, samples of minimal structural schemes of sentences and samples of conjunctions, allows choosing predicative structures of sentences in the text, realizing initial semantic analysis due to semantic content of predicate’s actants and building trees of syntactical subordination of sentences. The derived trees hold elements of tree of constitutives and tree of dependences. The proposed samples and rules organization allows resolving some of the problems of modern parsers. And the use of verbs’ valency dictionary allows reducing the number of sentences syntax analysis variants.

    Keywords: automatic text processing; syntax parser; morphological analysis; structural text elements

  • Modeling of MOSFET parameters in a wide temperature range

    The temperature dependencies of the main parameters of p-channel MOSFET model in a temperature range 20 ... 300 K are measured. The universal formal four-parametric model, which allows approximating all experimental temperature dependencies with the relative error less than 1 % is proposed. The model is intended for the MOSFETs which are applying in low-noise amplifiers of the radio-receiving devices of an optical and infrared range on astronomical satellites, radio telescopes and space observatories. The presented results can be used to simulate the temperature modes of MOSFET amplifiers in SPICE-type electronic simulators. The solution of this problem will predict uptime device when the temperature changes in the cases of emergency or extraordinary situations and also will allow optimizing the choice of refrigerant and increasing the reliability of the amplifier in the conditions of cryogenic temperatures.

    Keywords: MOSFET, MOSFET parameters, cryogenic temperature, parameters measurement, temperature dependencies

  • A method of providing of ecology and technical security at traffic areas

    This article is devoted to reviewing of crusted composition, based on natural minerals: magnesium chloride (bischofite) and glauconite, as a method of providing an ecological and technical security at traffic areas. In one of the main parametres of road safety - the coefficient of coupling revealed the advantages of using of eco composition over other commonly used anti-icing agents.

    Keywords: crusted eco composition, icemelter, coefficient of adhesion, accident rate, ecological security, technical security