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  • 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

  • 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

  • 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

  • Features a selection of piezoceramic sensors for monitoring the structural unit of waterpipe supply systems

    Features of sampling of the piezoceramic transducer for the arrangement of structural monitoring of water supply systems are in-process observed and calculations of basic performances of the sensing transducer (material PZT-5A) are led

    Keywords: piezoceramic transducer, ultrasound, monitoring, structure, extending, water supply systems

  • The development of effective fiber-reinforced concrete structures for underground construction

    The most promising technologies of concrete and reinforced concrete for the underground construction and transport. The studies with the inclusion of concrete and steel and polypropylene fibers. The factors affecting the strength and modulus of deformation materials. The conclusion about the need to study the effectiveness of the concrete with a combined reinforcement.

    Keywords: Concrete and underground construction, fiber, strength, modulus of deformation

  • 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

  • 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

  • A description of the potential function for the more accurate equation of lines motion

    In the present work proposes a specified description of potential functions when the free spreading  in the two-dimensional turbulent flow of planning. In contrast to previous decisions, new parameter satisfies the continuity of flow when the flow flowing  from rectangular tubes on the discharging  track  

    Keywords: final line of motion, lines of equal potential, horizontal rectangular tube, diverting from the mainstream flow

  • 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

  • Raman spectroscopy as a method for structure analysis of individual carbon nanotubes

    In this paper a systematic study of individual single-walled and multi-walled carbon nanotubes was performed by Raman spectroscopy and high-resolution electron microscopy. We have presented the geometrical and electronic structure analysis on the examples of two tubes: individual single-walled and double-walled nanotubes. The role of different environmental effects and their influence on the final structure assignment are discussed. Moreover, we have shown that the Raman spectroscopy gives reliable estimations of the nanotube diameters and the conductivity. Given a non-destructible character of Raman spectroscopy, we may conclude that it is one of the most efficient methods for structure analysis of carbon nanotubes.

    Keywords: Carbon nanotubes, Raman spectroscopy, electron microscopy

  • Parametric model of pseudorandom sequence generator by OrCAD

    This article describes the model of the pseudorandom sequences (PRS) generator developed in OrCAD program suite.The described model is applicable for radio systems modules circuits simulation that are using in the operation a PRS. The PRS generator implementation in OrCAD make possible to change PRS parametres immediately in the program, without using other software. A model specificity is that it is parametrised. Parametrization facilitates model control and that is reduce to a minimum necessary manipulations for changing of PRS type. The model is constructed on the basis of circuitry implementation of the linear feedback shift register (LFSR). For adjustment of model it is enough to instal code words setting starting state a LFSR, parametres of a signal of a clock source and to specify register tap output. As an example, used a 16-bit LFSR to create maximum length PRS, tap sequence {0, 5, 9, 13}. Emulation results are presented.

    Keywords: pseudorandom sequence, PRS generator, LFSR, OrCAD, circuit simulation