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
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
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 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
This paper outlines the implementation of computer model of second-order visual mechanisms that are specific to spatial contrast modulations, and represents the results of testing the model. Computer simulation is based on "Filter-Rectify-Filter" model with some important additions. The inhibitory parts of receptive field of simulated mechanism are non-selective to orientation and spatial frequency of texture elements. Texture modulated by orientation or spatial frequency does not reduce flank inhibition and does not activate the mechanism. Unmodulated texture also does not cause activation of the filter because the flanking inhibition will be equal to or exceed the excitation. However, increasing the contrast in the center and reduction it on the flanks leads to the activation of the second order mechanism.
Keywords: Second order visual mechanisms, image filtering, texture, spatial modulation, computer simulation
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
In the article authors examine specificities of internal components behavior changing in fiber-optical cable under influence of strong variable uniform electromagnetic field. There are some process variations proposed for describing of obtained results.
Keywords: fiber-optical cable, electrothermal degradation, kevlar, conductivity, open fiber-optical cable, partial discharges, water treeing
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
In this work experimentally investigated the possibilities of the new method of obtaining adjustable roughness on metal surfaces electrothermal influence of mobile cathode spots in vacuum arc discharge. Presents the results of processing of various surfaces using this method. Proposed working modes of processing of metal surfaces with the aim to receive as minimum and maximum roughness.
Keywords: roughness of metal surfaces, vacuum arc discharge, cathodic spots
An analysis of the problem of increasing the efficiency of the functioning of the logging trucks for hauling timber to the lower timber depots and consumers. Proposed technical solutions for of raising cross-trains in complex natural and industrial environments.
Keywords: Active semi-trailer used forestry, passableness, prosary operation.
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
The method of digital parametric measurement of the phase shift of signals with slowly varying amplitudes of the same slowly varying instantaneous frequencies was proposed. The numerical simulations and experiments on the developed hardware and software system were carried out. The error of measurement the phase difference of harmonic signals in the experiments were not more than 0,00001 radian. The method can be used in applications where the measured value is expressed in terms of the phase difference of quasi-harmonic signals.
Keywords: quasi-harmonic signal, phase shift, real time measurements, hardware and software system
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
Proposed by parallel implementation structures aloritmicheskih simulating year-round circulation of water bodies. The research evaluation of computation time, find the optimal algorithm for the implementation of independent calculations for multi-core processors to reduce the computation time.
Keywords: parallelization of computations, thermohydrodynamics modeling of water objects, multi-core processors
In modern conditions, of particular importance is the need to form a model of the reproductive system of the regional economy, adequate objectively existing level of technological development, trends involvement in every phase of the reproductive process of innovative products, intellectualization of human activity, as well as the new requirements of economic globalization of world economic relations. In this regard, there is a need for a management model reproductive potential, focused on the balanced development of all the subsystems of the regional economy, taking into account the factors of integration and globalization of the world economy.
Keywords: balance, reproductive potential, production function, the economy of the region