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  • Comparative evaluation of changes in reliability of methane-diesel and diesel cars, depending on seasonal conditions

    The paper presents the results of a study on the influence of seasonal conditions on the reliability of diesel and gas diesel vehicles. During the experiment were treated with statistical data on the failure of the two groups of trucks, methane-diesel and diesel operated under the same conditions. As a result of analysis found seasonal variations in the flow of failures between the two groups. Then the failures were divided into failures of components and assemblies cars such as engine, transmission gear and chassis of cars. This division has revealed the influence of seasonal conditions on the reliability of components and assemblies of diesel and gas diesel cars and their differences. Studies have shown the need for adjustment of norm in the planning of maintenance and procurement of spare parts for gas diesel vehicles.

    Keywords: Stream failure, gas equipment, seasonal conditions, the reliability of vehicles, maintenance and repair

  • Simulation of parallel operation of three-phase distribution transformers

    Modeling of parallel operation of distribution transformers with thyristor voltage and powe regulator are considered here. Models are made in Simulink. Structural model of parallel operation of two three-phase transformers is presented. Model allows us to study electromagnetic processes at phase by phase control.

    Keywords: three-phase transformer, parallel operation of transformer, simulation, Simulink.

  • Elements of geotechnical monitoring of underground constructions, enshrined concrete anchors

    There was a need for geotechnical monitoring during construction of underground facilities. The organization of monitoring control tensile forces in the concrete anchors. Comparison of experimental and calculated data, which revealed that the deviation does not exceed 19%. When using anchor embedment length limited in a large range of conditions in a rod anchor having critical internal forces. To increase the efficiency of anchors in their construction can be used in flexible elements of the anchor bolt assembly.

    Keywords: underground construction, monitoring, anchor well, tensile forces, the bearing capacity, the compliance node

  • Theoretical and experimental bases of assessment of the arched part transport tunnels using the method of acoustic resonance inspection

    The article presents the main results of theoretical and experimental research in the field of non-destructive testing and forecasting of geomechanical condition of the arched part of the transport tunnels. It has been shown that this goal can be to apply a method of acoustic resonance inspection. Methodology Research was registering the resonant response of the layered rock mass to impact mechanical excitation of an acoustic signal. Initiation and receive elastic vibrations produced in the lower layer of the breed. These technical and economic parameters allow to recommend Geophysical prediction described underground geophysical methods for wide industrial use during transport tunnels

    Keywords: geomechanical state geological environment, the array, evaluation, arched part, the transport tunnel spectrum, acoustic resonance inspection, prognostication, control, forecast, weakened mechanical contact

  • Scientific organization of labor as a factor of increasing the efficiency of agricultural enterprises

    This article provides the background necessary to use the basic principles of scientific organization of labor as one of the main factors of internal efficiency improvement of production activities of the enterprises. Set forth in article a brief history of the emergence of the scientific direction and the peculiarities of agricultural production left no doubt as to the necessity of implementation in the process of organizing the production of scientific organization of labor.

    Keywords: scientific organization of labor, scientific management, standardization of labor, stimulation of labor, delegation of authority, communications

  • Modification of Pan-Thompkinson’s real-time QRS detection algorithm

    The article discusses the Pan-Tompkins algorithm to detect QRS complexes in real time, when applied to a PC for analysis of records not in real time and pre-recorded. QRS complexes detection algorithm was published Dzhiapu Pan and J. Willis. Tompkinson in the journal IEEE Transactions on biomedical engineering, vol. BME-32, NO. 3 in March 1985. The algorithm has been designed for use in real time. Pan and Tompkinson developed an algorithm for real-time detection of QRS complexes of ECG signals. Algorithm for QRS complexes reliably recognize, by analyzing the inclination of the complex amplitude and width. Special digital bandpass filter reduces the number of false detections caused by different kinds of interference present in the ECG signal. This filtering allows the use of low detection thresholds, thereby increasing the sensitivity of detection. The algorithm automatically adjusts thresholds and parameters periodically to adapt to such changes ECG QRS morphology and as the heart rate. For standard recording duration 24 hours from the database MIT / BIH arrhythmia database, this algorithm correctly recognized 99.3 percent QRS complexes. However, this time the algorithm is rather outdated, as it was designed for computers that time. With certain modifications and current capabilities, parameters can improve the quality and speed of analysis. A modified version of the algorithm has been developed for use in the client software mobile multifunctional hardware-software complex and long-term cardiac monitoring ergonometrii. Better and more precise analysis of QRS complexes in the signal more accurately assess the state of the cardiovascular system of the person, which is an important factor in the treatment and diagnosis of heart disease in the early stages.

    Keywords: ECG, accurate analysis, detection of QRS, algorithm Pan-Tompkinson, cardiovascular system.

  • Preparation and study of the optical properties of arrays of Au nanoparticles on the surface of thin films of ZnO

    Research of possibility of management of morphological parameters of arrays nanoparticles Au (form, the size, density of superficial distribution) of the thin films of ZnO received on a surface by method of the pulse laser deposition (PLD) with subsequent annealing in the inert atmosphere was conducted. It was experimentally established that increase of the average size of Au nanoparticles leads to the plasmon peak broadening and its shifting to the red region. Nanoparticles with diameters 17, 25, 31, 37 and 40 nm have plasmon absorption maximums at wavelengths 570, 590, 605, 610 and 620 nm, respectively. With the increase of the average nanoparticle size nm to a certain value rise of maximum in absorbtion spectra at wavelengths 570, 590, 605 and 610 followed by its decrease at 620 nm is observed. The highest value of the intensity at/in the absorption maximum corresponds to the average diameter of the nanoparticles of 37 nm. Optimal conditions for synthesis of isolated arrays of Au nanoparticles on the surface of ZnO thin films with high maximum of plasmon absorption were experimentally found. Obtained results can be used to increase the sensitivity of the photodetectors and solar cells based on zinc oxide or chemosensors based on Raman amplification effect near the gold nanoparticles.

    Keywords: nanoparticles of Au, arrays of isolated nanoparticles, plasmon resonance, a photodetector, photosensitivity, ZnO film

  • Multilevel system of distributed control smart grid

    Recently becoming urgent problem of managing distributed processes of production, transmission and consumption of energy. This fact is associated with the emergence of a significant number of generators and the possibility of a primary control on all elements of the grid. In this connection, in proposed three-level distributed power grid management, which includes the upper level of segmentation networks, distributed control average frequency and power level and a lower primary control. The methods of control for each of the above levels, the results of simulation.

    Keywords: smart grid management system, distributed control, frequency control and power.

  • Use hidden Markov models at synthesis of stochastic algorithm of the solution to the problem

    This paper, based on the content of the axioms for the randomized algorithm, considers the collection of using correct algorithms at synthesis for solving the problem of probabilistic hidden Markov model. Application of this model allows forming algorithm with its flexibility according to a substantial situation for ensuring structural and functional stability of the program realizing this algorithm. We found that randomization of the algorithm, increasing its flexibility and efficiency, does not improve its risk compared with the corresponding deterministic algorithm. The synthesis of the algorithm based on hidden Markov model implies that the available observed data is used to determine hidden parameters of the most likely sequence of states, determining the synthesized algorithm. At the first strategy step, the "back and forth" algorithm is used to evaluate how well the model matches with the input data of the synthesized algorithm. At the second stage, the given hidden Markov model with the space of hidden states, initial probabilities of presence in state i and probabilities of transition from state i to state j, and basing on the observed states and using the Viterbi algorithm, the Viterbi path is found. At the third strategy stage, the hidden Markov models are corrected by optimizing the parameters of the model using the Baum-Welch algorithm.

    Keywords: hidden markov model, "back and forth" algorithm, viterbi algorithm, Baum-Welch algorithm

  • Modeling of state support mushroom

    The article presents a mathematical model of state support for producers of fresh cultivated mushrooms

    Keywords: The production of fresh cultivated mushrooms, state support and regulation of production, economic-mathematical model

  • Determination of reliability indices of the "operator -mining machine - environment" method of functional networks

    The paper considers method of estimating reliability indices of activity excavator operator with functional circuits. Been calculated the probabilities of error-free performance of three groups of workers (high-sufficient and satisfactory).

    Keywords: operator, man-machine system, the method of functional systems, excavator, functionaries kompozitsionery, functional diagrams

  • The selection of materials and technologies of printing on the surface

    The article provides an overview of different technologies for applying images onto a flat surface of the workpiece mechanical dot-impact photo printer on the basis of practical experience, reasons for marriage and remedies, types of material.point-impact photo printer and suggest methods to eliminate it.

    Keywords: workflow, photo printer, a dot-impact engraving, image distortion parameters blanks

  • Cognitive cultural and leisure installations of students of DGTU on the middle of 2015.

    Results of poll of students of the Don state university about a cultural complex of the Rostov region are given in article. The main cultural and leisure installations of respondents, their relation to cultural infrastructure of Rostov-on-Don and area, their main cultural interests are shown. On the basis of these data conclusions are drawn on the level of satisfaction of cultural requirements of students.

    Keywords: cultural complex of the Rostov region, cultural requirements, sociocultural elements, cultural services

  • Hall gradiometer

    The article deal with gradiometer is designed for remote nondestructive testing of various purposes pipelines. Gradiometer sensor consists of two Hall-effect transducers three-component magnetic field placed at a distance of 1950 mm from each other. The specialized algorithm for reducing transducer’s bias error is used. The gradiometer sensor’s orientation relative to the pipe axis is determinate by the digital microelectromechanical system. The results of measuring the gradient of the magnetic field induction, module, and the coordinates of the sensor are displayed on the LCD display and saved on non-volatile storage.

    Keywords: magnetometry, nondestructive testing, gradient of the magnetic field, the Hall sensor, magnetometer, gradiometer, magnetogram

  • Comparison of Raman amplification parameters in photonic crystals of different configuration

    The optimization of multilayered one-dimensional nonlinear structure of Raman amplifier of optical signals consisted of alternate active nonlinear metal layers and passive dielectric has been studied. The amplification of the reflected and passed field energy was calculated for different structure types. The effective replacement of passive layers by active media in the middle and in the end of structure has been demonstrated.

    Keywords: raman scattering, amplifier, photonic crystal, nonlinear effect, photonic bandgap