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  • Long-term monitoring of human respiratory activity

    This article reviews systems of respiratory activity registration in relation to sports medicine. Attention is devoted to the use of miniature accelerometers that record the movement of the chest, as the optimal method for the diagnosis of the respiratory parameters. Other methods are based on piezo-resistive sensors, pressure and airflow sensors, and airways resistance sensors. The authors' developed device based on three-axis accelerometer is proposed. It recognizes episodes of apnea with sufficient accuracy for long-term monitoring. The algorithm of the accelerometer data processing is described. In order to minimize noise impact on the useful signal it is necessary to transform the three-dimensional cloud of accelerometer data into a flat sector. Then the relation of gravity vector deviation angle and the nominal position in time is determined. This presented device due to its ability to transmit data via Bluetooth technology, after appropriate software development for mobile phone and the receiving terminal of medical professional, will be able to organize a simple ergonomic long-term remote monitoring of respiratory activity.

    Keywords: systems of respiratory activity registration, long-term remote monitoring, three-axis accelerometer

  • Local atomic and electronic structure of nanostructured condensed materials for rechargeable current sources on the basis of V2O5/Fe/LiF nanocomposite within charge-discharge cycle

    In this paper we study of the local atomic and electronic structure of nanostructured condensed material for rechargeable current sources on the basis of 15mas.%V2O5/Fe/LiF nanocomposite within charge-discharge cycle. Principle component analysis (PCA) of the series of Fe K-edge spectra collected during 1 st charge showing the concentrations of the components Fe, FeF2 and V[FeV]O4. We found the changes in the V oxidation state from the analysis of the experimental Fe K- and V K- XANES spectra. Total and partial density of states of components are presented.

    Keywords: nanostructured materials for rechargeable current sources, dynamics of local atomic and electronic structures, XANES, DFT

  • 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

  • Research of Nd:YAG laser processing on intense the deformed conditions in semiconductor structure

    Results of research of influence of  processing operations of Nd:YAG of the laser are presented in article, such as the speed of scanning and power of a laser beam on maximum temperature and the thermodeformed status in structure dye-sensitized solar cell. Dependences a component of a tensor of tension are received at various processing operations by means of numerical experiment. Results of researches showed that in intense the deformed status is depend on  temperature gradient more, then on coefficients of linear expansion of structure which in this structure differ slightly.

    Keywords: laser technologies, thermodeformed, numerical simulation

  • 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

  • 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

  • Term of self-bearing fiber-optical cable electrical conductance. Experimental information

    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

  • Transformational training and holistichesky approach in the information and educational environment of technical University

    Questions of modernization of higher education on the basis of development of structure of the hi-tech information and educational environment of technical college are considered. Transition to new structure of the educational IT infrastructure aimed at formation of open educational system, meeting modern requirements to engineering preparation is carried out. 

    Keywords: transformativny training, holistichesky approach, the information and educational space, the integrated system

  • Rationale for ways to increase efficiency operation of logging truck

    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.

  • 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

  • The parametric method of determining a phase difference of quasi-harmonic signals

    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

  • 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

  • Process Dynamics Modeling on the Base of Text Corpus Sequence Analysis

    The represented approach of dynamic process modeling is based on the technology of automatical semantic text analysis. An associative network is forming during text processing. Its key notions, including  lexical and psycholinguistic markers of the analyzed process, are ranked by theirs semantic weight. The weight being multiplied by marker status value at the scale of “good-bad” gives its contribution to the process stage characteristic. Transformation of the accumulated for all of the markers process characteristic from one period of time to another one is characterize a direction of the process.

    Keywords: automatical text processing, associative (homogenous semantic) network, process dynamic modeling, social processes, lexical and psycholinguistic markers