The article describes the research of thermodurability of glass-carbon - one of the most promising carbon materials used in the production of luminophors and semiconductor materials, optical single crystals, etc. The aim of this work was to study the behavior glass-carbon in the course of thermo-cyclic testing. As a method of diagnostics of the birth and development of micro-cracks was used by the reception of signals of acoustic emission. It is shown that at heating in the samples glass-carbon there was a strong movement of dislocations in thermocyclic effects ,recognized in the signals of acoustic emission. As the number of pulses when heated above, than during the cooling of the sample, it is evidence of the accumulation of damages in the structure of the cyclic thermal processing glass-carbon samples. It is established, that the curves of the accumulation of defects at the pulses of acoustic emission, differ on the stage of heating and cooling. Proposed to use the curve of the aggregate accounts of acoustic emission pulses as a possible harbinger of destruction when heated glass-carbon of the product.
Keywords: acoustic emission, electrodeposition, the activity of the AE, the remote control.
In this paper a modification of logic element DC LUT FPGA is proposed for the purpose of the acceleration of diagnostics. Simulation of proposed modification was performed in the system NI Multisim 10 by National Instruments Electronics Workbench Group. Evaluation of hardware costs is also given.
Keywords: logic element, DC LUT, FPGA, diagnosis, reliability
The research of influence of periodical signal discontinuity on spectrum form is considered in the article. The numerical modeling of the system of discontinuous signals is performed. The spectrum of the system built from time discreet sampling is analyzed. The plots of the sample correlation coefficient between spectrums of continuous and discontinues signals are shown in the article. The research is needed for the development of digital measuring system for quartz plates frequency detecting.
Keywords: amplitude signal spectrum, discontinuous signal, quartz plates
The article is devoted to mathematical modeling of high frequency electrothermic of thermoplastics in relation to a technological system in the form of the component plate, including electrodes, insulators, the processed material, and the study of the influence of termoisolation on heating of the thermoplastic. In the article the mathematical model in the form of a system of nonstationary heat transfer in considering the internal heat sources with different boundary conditions and delivers its software.
The software provided in article enables to study the influence of geometrical and electrophysical parameters of technological systems of high-frequency heating of the thermoplastic. In this article the results of research of influence of termoisolation on the nature of the heating of the thermoplastic. Based on the calculations presented in numerical and graphic kind, identified the following areas of heating polymer: uniform heating, regional zones of thermal influence of insulators. Heat-affected zone is characterized by depth and temperature of the contacting surfaces. The thickness increase of insulators over a certain value does not change the zone of thermal influence of insulators, which allows to speak about effective from the energy point of view of the thickness of the insulator, the excess of which increase energy consumption, time of heating of the polymer.
Conclusion is made according to result of the study about the necessity of the presence and settings termoisolations when building technological processes electrothermic of polymers. The developed software allows a new approach to the study of the RF heating, ensuring minimal energy consumption while ensuring uniform heating details.
Keywords: electrothermics, thermoplastic, mathematical model, polymer, thermoinsulator, welding, drying, polyamide, high-frequency treatment
The article gives IT-companies and their software products review in the field of engineer analysis and calculation. The importance and intensive development of this sphere IT-companies through their works and service refining, that facilitates their new market segments introduction, is shown.
Keywords: CAE, engineering, intellectual property, IT-technology, software products, CAD
Application features of dynamic memory devices based on binary fiber-optic structures are researched in optimal filters of sequence of pulse signals.
The possibility of significant improvement of signal-to-noise ratio in optimal filters of sequence of pulse signals using non-recirculating binary structures compared to recirculators is proved.
Application of the technical solution based on the method of enhancing identity copies in binary fiber-optic structures allows to achieves the gain in signal-to-noise ratio of about 37 dB for 4096 copies processed, this corresponds to the gain of 22 dB compared to typical recirculator.
Keywords: binary fiber-optic structure, optimal filter, pulse sequence, signal-to-noise ratio
Coding of information using of pseudo-random sequences in quantum communication systems providing an operation with a low probability of single-photons detection is proposed. The results of statistical modeling of information extraction from the bit stream, received at different specified probability of detection based on the correlation properties of the M-sequences are demonstrated. It's demonstrated that the peak value of cross-correlation function for the M-sequence of 255 bits is on the average more than 2 times higher than the level of side lobes at the probability of single-photons detection 20%.
Keywords: quantum communications, single-photon detector, maximum length sequence
Thermal treatment of Fe-Co-V as an instrument to improve soft-magnetic material devices quality
The process of optimizing the thermal treatment Fe-Co-V alloys used in the magnetic torque motors is studied in order to improve the magnetic properties. It is shown that to achieve high and stable magnetic properties of the alloy it must be annealed in vacuum using inactive coatings. Regime of the annealing process depends on the quality of the original alloy. Quality verification is carried out by measuring the magnetic properties of the control samples . Identifying optimal annealing regime is based on the analysis of a phase diagram of Fe-Co alloy. In connection with that the research of influence of the heating rate , maximum temperature and holding time , cooling rate on the behavior of the magnetic parameters of the control samples is carried out. It was found that the improvement of the magnetic properties is achieved by increasing the exposure time to 6h at the cooling rate of 100 °/hr. As a result a reduction of the coercive force (60 ÷ 50 ) A / m to (28 ÷ 32 ) A / m and increased magnetic induction of technical saturation from (2,0 ÷ 2,10) Т to (2,20 ÷ 2.26 ) T. for Fe-Co-V alloy are achieved. Research of the exposure time and the cooling regime caused a decrease in coercive force of the Fe-Co alloy.
Keywords: Heat treatment , the annealing conditions , Fe-Co-V, technical saturation induction , the coercive force
By self-propagating high-temperature synthesis (SHTS) prepared fine powder оf La2-xSrxNiO4 composition , which is used to obtain dense ceramics exhibiting the properties of n-type semiconductor. Prolonged annealing of the samples resulted in a decrease of the conductivity on the order of 3-4, and the changing nature of the dielectric spectrum: dielectric constant ε' has a stable value of 4·104 Hz in the range of 0,4 − 1·105 Hz .
Keywords: dielectric constant, phase separation, nikelate of strontium lanthanum, self-extending high-temperature synthesis
According to the signal theory vocal speech presents a non-stationary random process due to time variation of its main characteristics. A special emotional impact is gained during ensemble and choir performances. The article provides the correlation analysis results and the autocorrelation function of ensemble singing calculated, taking into account the non-stationary nature of acoustic signals. The studies have shown that there is a certain visual resemblance between correlation portraits of a non-professional student ensemble and a non-professional solo singer. At the same time the correlation portrait of student and professional co-performance tends to a professional singer correlation portrait. This helps to make a quantitative assessment of an ensemble’s professionalism which, alongside with a vocal teacher’s subjective assessment, can provide an objective view on singers’ voices condition to optimize the academic voice training process in an ensemble, which is important when using this voice assessing method in music schools, colleges and universities.
Keywords: Vocal speech, acoustic signal, ensemble singing, choir performance, non-stationary random process, autocorrelation function, quantitative assessment
Based solutions of avalanche transit diode amplifier for under the influence of microwave amplitude- modulated optical signal at the p-n junction diode is determined by the response of the amplifier , while a detector device characteristic. We investigate the influence of numerous system parameters on product detection.
Keywords: frequency response; avalanche diode; amplifier; detector; Microwave amplitude modulated optical vibration .
The article presents the results of experimental investigations of carbon fabric electrodes for recording electrical biosignals. Experimental studies of carbon fabric electrodes showed good results both in conductivity and usability, for example, for further integration into clothing, that indicates the high quality of carbon fabric electrodes and promising for further uses for cardiac monitoring.
Keywords: Electrodes, carbon fabric, electrical biosignals, cardiac monitoring.
There is an important task to improve timber complex. It is a search of efficient using wood. The research results of energy reserves capacity running on a regularized round timber production technological line for wood construction are given in the article. The research suggests that 40 – 45 percent wood resources using on regularized round timber production technological lines are waste. This capacity can use for manufacturing different energy products: firewood, chip fuel, fuel pellets, fuel briquette. The research made on the plant (limited liability company “Biogrant”) in Karelian Republic.
Keywords: Woodworking, cylindering, technological line, wood costraction, energy reserves, fuelwood, firewood, chip fuel, fuel pellets, briquette
Calculation of coefficient of operating conditions of the pipeline is presented in article for the West Siberian region. Dependence of service life of the pipeline on this coefficient is presented. The data of samples witnesses received in laboratory of nondestructive control, confirming relevance of this subject are provided.
Keywords: corrosion, wall thickness, standard service life, pipeline, coefficient of working conditions, diameter, pressure, settlement resistance.
the problems of moisture (cooling) in the mass-transfer apparatus at different parameters of fluid spray and varying the magnitude of the influence of the electric field in the zone of the spray.
Keywords: heat and mass transfer, mist dispersion, electroaerosol, electrostatic dissipation.