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  • Calculation of the efficiency of optical radiation input of DFB and VCSEL lasers into a glass integrated optical waveguide

    The efficiency of optical radiation input of semiconductor lasers of various types into an integrated optical ion-exchange buried waveguide in glass was calculated using optical circuits based on spherical, hemi-cylindrical and hemispherical lenses. Calculations were made by using the method of ray tracing. The single-mode waveguide, used in calculations, is the glass (type K-8) waveguide, made by ion exchange with subsequent burying. The results of the calculations indicate a low efficiency of optical radiation input when using single lenses. The use of a pair of microlenses (collimating and focusing) makes it possible to significantly increase the efficiency of optical coupling, which is 79% for a VCSEL laser. Efficiency of input is limited by a sufficient low aperture of the glass waveguide itself - 0.12. For more precise simulations the race tracing method with wave correction was used. The wavelength of optical radiation for calculations is 1.3 micrometer. The use of a single spherical and cylindrical lens has the advantage for it’s simplicity, but will lead to a serious loss of power in the optical system and, correspondingly, an increase of signal attenuation. This is partly due to reason that when using a single cylindrical or spherical lenses, according to the geometry of the calculations, the optical radiation will not be focused at one point, and essential aberrations take place. Efficiency of coupling with the help of two lenses is limited at first, by numerical apertures mismatch and, at second, partial energy transfer to the rings of Airy disk. The ion-exchange waveguide is suitable for coupling with VCSEL lasers for application in planar waveguide concentrators, etc.

    Keywords: integrated optics, optical waveguides, ion exchange in glass, VCSEL laser, ray tracing method, ZEMAX

  • Self-consistent model of the sol-gel process of film formation on substrates with homogeneous precipitation of particles of hydrated oxides

    This article analyzes the regularities of precipitation of solid colloidal particles of hydrated metal oxides on the surface of various substrates. Two models of this process are proposed. The proposed α-model is a process of continuous nucleation of interaction centers, at random points of a free surface throughout the process. The proposed β-model provides for the instantaneous nucleation of these centers when they are randomly distributed over the entire surface of the substrate. Based on the proposed models, the average values of the following values are calculated: the thickness of the gel film; its roughness and specific surface area. The calculations carried out in the article showed that these parameters are universal functions of the degree of filling of the surface and do not depend on the specific model of the mechanism of the process.

    Keywords: modeling, homogeneous precipitation, formation of thin films, sorbents, catalysts, heat-resistant composites

  • Study of the bond strength of zinc electroplating with the surface of the machine parts from gray cast iron by planning a factorial experiment

    To ensure the stability of the galvanic deposition process and the high quality of the precipitate obtained, it is necessary to know the dependence of all processes on technological factors and modes. The degree of influence of technological factors on the behavior of machine parts made of gray iron, etching and deposition of zinc electroplating is not the same, so there is a need for electrochemical studies in the laboratory. The methodology of such studies has a General orientation and particular conditions in each case. The article describes in detail the method of electrochemical studies of gray cast iron in the sulfuric acid electrolyte of galvanizing during the restoration of machine parts by galvanic deposition of zinc coating. The basic conditions necessary for obtaining reliable comprehensive results that will determine the optimal conditions for galvanizing machine parts made of gray cast iron are considered.

    Keywords: technological factor, electrochemical studies, polarization curves, electrochemical cell, electrode, potentiostat

  • On the issue of additional distance education program " Use of information technologies in engineering, scientific, administrative and management activities» Part II

    The article presents information about the training program "Use of information technologies in engineering, scientific, administrative and management activities", developed within the framework of the project of the "Engineering open public forum of scientific and technological activities, social and technological entrepreneurship "rozmys", which is carried out using the grant of the President of the Russian Federation for the development of civil society, provided by the presidential grants Fund. The program is intended for a wide range of engineers and specialists of industrial enterprises, scientists, research engineers, University professors, specialists in the field of administrative and management activities. In it, participants are invited to master a number of professional competencies in the field of organizational management using computer modeling. Forms of training are distance video lectures and practical classes. For each topic, an intermediate test is carried out, and their results are put up a final assessment. Participants who have successfully completed the training receive a certificate confirming the passage of 16 hour refresher course on our program.

    Keywords: distance education, advanced training, organizational management, computer modeling, computer simulators

  • Mathematical model of electromagnetic interaction of red blood cells in a narrow capillary

    Red blood cells (RBC) roll like tractor caterpillars along narrow capillaries. On the erythrocyte surface there are charges that, when moving together with the erythrocyte membrane, create a magnetic field in the vicinity of the RBC. Discrete charges are distributed uniformly on the surface of the RBC, their number can reach several million and the charges move together with the RBC membrane. The surface of the RBC is approximated by a truncated cylinder. Discrete charges are located evenly over the surface of the RBC and move along closed curves that are rectangular trapezoids. A mathematical model has been constructed that allows calculating the intensity of the magnetic field produced by mobile charges located on the RBC membrane. According to the Bio-Savart law, the magnetic field strength can be calculated at some point in space if the coordinates and velocity of the charge are known, the distance from the charge to the point and the angle between the velocity vector and the radius vector connecting the charge and the point. If we assume in the first approximation that the medium is isotropic and magnetic currents are absent, then Maxwell's equations can be written out. These equations can be rewritten in the form of equations in finite differences, solving by numerical methods one can obtain distributions of electric and magnetic field strengths in the vicinity of the RBC. Calculations were carried out for different values of input parameters. In the case when the RBCs move through the capillary network, in which the narrow capillaries are located close to each other, the magnetic fields of the RBCs in different capillaries interact, and, as a result, we obtain a new distribution of the magnetic field strength in the vicinity of the capillary network, which varies with time.

    Keywords: mathematical model, algorithm, magnetic field strength, electromagnetic interaction, erythrocyte, narrow capillary

  • Computer model of a fiber-optic sensor for measuring transverse pressure based on a two-frequency optoelectronic generator

    The article demonstrates a computer model of a fiber-optic sensor implemented on the basis of a two-frequency optoelectronic generator (OEG) for measuring lateral pressure. In the loop of the optoelectronic generator, a fiber Bragg grating (FBG) with a phase shift is applied to which a transverse pressure is applied to guide the birefringence and create two orthogonally polarized transparency windows, which leads to the generation of two optical frequencies. The difference frequency of the beats between the two optical frequencies lies in the microwave range and depends on the magnitude of the pressure applied to the FBG. It was modeled that the sensitivity and the minimum detectable pressure are ~ 10 GHz / (N / mm) and 2.5 × 104 (N / mm), respectively. The high frequency and stability of the generated microwave component of the optoelectronic generator provide an extremely reliable and highly accurate measurement. Frequency survey allows the system to operate at high speed. In addition, the measurements are insensitive to changes in the ambient temperature and the wavelength of the optical carrier.

    Keywords: transverse pressure, fiber optic sensor, fiber Bragg grating with phase shift, birefringence, optoelectronic generator, two-frequency optical signal with microwave frequency difference frequency

  • Mathematical modeling and restoration of optico-acoustic parameters of an air-gas stream on a turbomachine nozzle cut. Results of modeling

    The present article is devoted to development and a research of the distributed fiber systems of aero acoustic control of parameters of an air-gas stream on a cut of a nozzle of turbomachines. The main emphasis is placed on development and to a research of the distributed fiber systems on the basis of control methods the using multiplexed fiber-optical sensors of control of parameters of an air-gas stream on a cut of a nozzle of the turbomachines using advantages of optical methods of information transfer and the device for his realization. The principles of creation of the complex systems of aero acoustic cartography complemented with methods and measuring instruments of gasdynamic parameters of a stream in a flowing part and on a cut of a nozzle of the turbomachines directed to increase in informational content and level of algorithmization of nondestructive control of a condition of working shovels and providing data acquisition in the conditions of parametrical and structural uncertainty of an air-gas stream as on controlled internal sections of a flowing part, and on output section on a turbomachine cut are defined. Problems of placement of points of control and restoration of spatial distribution of the field of measurements in discrete set of points separately are considered. Restoration of the acoustic field of turbomachines is implemented according to measurements at the exit of WATERS, only using statistical approach. Restoration of the field is presented in the form of continuous functions of spatial coordinates by results of measurement in discrete set of points in the presence of aprioristic information on properties of the measured fields. Statistical approaches for determination of coordinates of sensors and an error of restoration on the example of one model problem of control of the field of the radiation created by the continuous exclusive radiator are used. Results of calculations show that existence of correlation between coefficients of decomposition of the field of radiation on functions, leads to reduction, necessary for achievement of the set accuracy of restoration of number of sensors.

    Keywords: distributed fiber systems, аero acoustic control, acoustic field, process simulation, recovery

  • Investigation of nonlinear waves on a surface a magnetizing liquid of infinite depth

    The problem of the propagation of nonlinear surface waves in a magnetized liquid of infinite depth is solved. The dependence of the frequency of wave oscillations on the magnitude of the magnetic field strength is shown in the graphs. Trajectories of motion of particles of liquid are found. The effect of a magnetic field on the height of a wave is investigated. The results of the study can be used to calculate various technical devices and technological processes.

    Keywords: surface waves, magnetizable liquid, magnetic field, wave number, frequency of wave oscillation, magnetic field intensity

  • Numerical simulation of laser annealing of a thin amorphous silicon film for solar cells

    Numerical modeling of the temperature distribution during heating (annealing) by a pulsed Nd: YAG laser of an amorphous silicon (a-Si) film on the surface of an AZO glass substrate is carried out. The simulation was performed on the basis of a numerical solution of the heat equation in the Matlab program to determine the energy density of the laser radiation necessary for crystallization of the a-Si film. For a wavelength of 1064 nm, it was obtained that the temperature at the surface of the a-Si film reaches a maximum value at a time point of 146 ns with a laser pulse with a Gaussian time-shape. It is shown that for the crystallization of an a-Si film with a thickness of about 800 nm with laser radiation with a nanosecond pulse duration, the optimum energy density is 600-700 mJ / cm2 when the temperature across the thickness of the a-Si film corresponds to 550-1250 ° C.

    Keywords: Numerical simulation, laser annealing, temperature distribution, a-Si film, solar cell

  • Design of information system of Parking lot operation optimization

    The article analyzes and simulates the business processes of Parking within the framework of the structural approach. The charts of IDEF0, DFD and ERD models created using AllFusion Process Modeler and ERWin Data Modeler software products are presented

    Keywords: Parking lot, process, modeling, analysis, business processes, CASE tools, IDEF0, DFD, ERD, software product, business process, chart

  • Mathematical modeling of the distributed ledger in the sphere of real estate lease as a network of mass service

    This article presents a mathematical model of the distributed registry as a Queuing network. The main components of this network, as well as their formal representation are considered. The model of the peer-to-peer network is visualized, the vector of the network state is defined, and the restrictions of the state space are defined. After that, the laws of distribution of individual flows and service time were presented. In addition, the design elements of the infinitesimal matrix were determined. Based on the data obtained, a simulation model of this process was produced. For simulation, the Anylogic package was used. The results of simulation were analyzed and the most optimal parameters were selected.

    Keywords: Queuing network, information security, distributed registries, computer science and engineering, mathematical modeling information system, corda

  • System analysis of reliability and prospects for its enhancement for consumer power supply systems

    The analysis of reliability of systems of an electricity transmission during which the main causes of the power outage in the consumer were identified. With the help of computer simulation, the results of operation of autonomous inverters are obtained with different number of voltage levels. The prospects of using the devices for balancing the incomplete-phase regimes on the basis of multilevel voltage inverters, which improve the reliability of power supply to consumers, are considered.

    Keywords: analysis, stream of the failure, electricity, the balancing device, emergency operation, recovery time, failure, reliability, multilevel inverter, power line, user

  • Complex approach towards the calculation of technological parameters influence onto Na-CMC rheological properties for drilling agents

    The possibility of getting natrium-carboxymethylcellulose with given viscosity from different raw materials for oil industry is shown in the paper. The regression model, connecting rheological characteristics viscosity with parameters of the technological process is proposed. The program for IDE Microsoft Visual Studio medium which may be used for calculating Na-CMC synthesis parameters, providing the given in the frames of the technological process viscosity value, is developed.

    Keywords: natrium-carboxymethylcellulose, rheology, viscosity, etherification, alkalinity


    The article proposes a technique for constructing a model for optimizing the taxation of profits for its implementation in the practice of organizations - large taxpayers in both the Rostov region and the Russian Federation as a whole. Methods for calculating the coefficients for assessing the efficiency of the mechanism for optimizing the taxation of profits of organizations - large taxpayers - are proposed.

    Keywords: financial stability, tax burden, tax benefit, optimization, taxation, taxpayer, profit

  • Interactive analysis of the distribution of labor resources

    The authors propose the implementation of a mathematical model in the form of an information module. The mathematical model is a problem of nonlinear programming, the solution of which allows to optimally distribute the labor resources on the basis of statistical data and economic indicators. The process of solving the optimization problem is automated with the help of the developed web service of interactive analysis and forecasting of the distribution of labor resources of the enterprise, industry, region and the country as a whole. The information module is a web service that allows you to analyze the distribution of labor resources online and offline. The example of the analysis of labor resources of Stavropol region is given.

    Keywords: labor resources, analysis, forecasting, information module

  • Effective organization of service requests using the example of a unified user support service for JSCo "RZD"

    Describes the process of processing applications single user support services (UPCS), jsco «RZD», presented the objectives of the project. Are the standard time for work performed in the UPS. A model for evaluating the timeliness of processing applications, UPS created users software package. Assess the appropriateness and timeliness of information from UPCS users. The smallest probability of timely information UPS during the day will be observed from 8.00-9.00 am on Monday and from 17.00-19.00 p.m. on Friday. The optimal number of service channels for the stated criteria for timeliness of processing applications is 7

    Keywords: information technology, UPS, ITSM, treatment, timeliness, processing, registration, circulation model UPS, channel services, ITC

  • Approaches to real estate market modeling

    The real estate market model based on dependence of the price on appeal of housing is offered. The results of assessment of adequacy to the offered model received during the research of 22 real estate objects of the city of Perm during the period from 2016 to 2017 are given. The structure of the tree of criteria forming a complex indicator "appeal of housing" is offered. Restrictions of use of the offered model are revealed and also the fields of her admissible use are described.

    Keywords: market model, real estate object, complex estimation, tree of criteria, appeal of housing

  • Mathematical modeling of the stress-strain state of an elastic mass near a spherical cavity taking into account the technological heterogeneity of its mechanical properties

    It is considered a centrally symmetric stress-strain state of the rock mass near the underground spherical cavity taking into account the technological heterogeneity of the rocks of the near-edge region. The mathematical model was developed and analytical solutions were found for this problem. The technological heterogeneity of the elastic properties of the rock mass material was modeled by a radially inhomogeneous coefficient of elasticity at a constant Poisson's ratio. The variable coefficient of elasticity for heterogeneous rocks was approximated by a generalized polynomial with undetermined coefficients. On the basis of experimental data, a numerical calculation of the stress-strain state components for the problem was carried out, and characteristic effects were detected.

    Keywords: stress-strain state, rock mass with technological heterogeneity, underground spherical cavity, mathematical model

  • Data analysis based on private cloud technology

    The article is devoted to the use of a private cloud for data analysis. Modern cloud technologies can significantly reduce costs, and today many companies are increasingly moving their corporate systems and business applications to the cloud, including the data analysis process. The aim is to analyze the quotations of precious metals for the period from 01/01/2018 to 08/01/2018, taken from the information portal Finam.ru for retail traders. To achieve this goal, the following tasks were set: network virtualization, projection of a private cloud based on Microsoft System Center Virtual Machine Manager 2012, the development of a service for forecasting data on precious metal quotations (gold, silver, platinum, palladium) using a time series algorithm and a decision tree. The subject of research is the technology of the private cloud, use it to deploy the service to analyze the data. In the conclusion the results of the service are shown, the practical use of cloud computing for data analysis is shown. The evaluation of the quality of the constructed models makes it possible to consider it satisfactory from the statistical point of view.

    Keywords: cloud computing, private cloud, data mining, cloud service, virtualization, data analysis, forecasting

  • Development of a model of the process of internal corrosion of pipelines of heating networks

    A dynamic model of the process of internal corrosion of pipelines of heating networks is considered. Model include five level: the level of the wall thickness of the pipeline, the level of slowing down of thinning of the wall of the pipeline from pH, the level of accelerating of thinning of the wall of the pipeline from temperature, the level of accelerating of thinning of the wall of the pipeline from the oxygen concentration, the level of slowing down of thinning of the wall the pipeline from the carbonate index. The composition of variables includes one level of state, thar characterize the process of thinning the wall of the pipeline due to internal corrosion, and four levels, that characterize the performance of network water. Six rates of changing of the physical indicators, that characterize the growth (dynamics) of the ongoing process, are taken into account. Four dependencies of influence are connect the subsystems of the complex into a single whole. The results of the evaluation of the dynamics of the pipe wall thinning process in the process of internal corrosion for a period of 1 year and 5 years presented. The software implementation in the Mathcad environment is considered.

    Keywords: dynamic model, internal corrosion of pipelines, corrosion of the heat network, corrosion factor

  • Computer simulation of interaction of silicate and phosphate additives by quantum chemical analysis

    This paper presents two methods of computer simulation (quantum chemical analysis and molecular dynamics) of the interaction of additives with the iron surface. Quantum chemical interaction of silicate and phosphate additives with iron surface was carried out. The plate model was used for quantum chemical analysis, calculations were carried out in the DFT approximation. The method of molecular dynamics is based on the calculation of the evolution of the system of interacting particles of atoms and molecules by integrating the equations of their motion. It is shown that the oxidation of the surface leads to a decrease in the adhesion energy of both individual additives and their combinations, allowing to find the influencing factors on the behavior of tribosystems.

    Keywords: lubricant, method, quantum chemical analysis, molecular dynamics, tribology, friction, computer simulation

  • Software implementation of automated annotation of documents

    The article provides an overview of the methods of automatic abstracting and annotating documents. The description of classification of methods of annotation and abstracting on various criteria is presented. The algorithm of automatic annotation is described in detail, the key step of which is the transformation of all words in the text into lemmas (lemmatization). The developed program sets the upper limit of the output annotation in order to avoid receiving the abstract instead of the annotation.

    Keywords: annotation, abstracting, lemmatization, algorithm, software implementation, database, text analysis

  • A synergistic method for the control crawler platform

    The problem of synthesis of the speed regulation law and the angle of rotation of a crawler platform with DC electric drives in a nondeterministic medium is discussed. The solution of the task is achieved by using a synergetic controller with a hierarchical control principle. The crawler platform control is considered on the basis of the mathematical model of platform motion and electric drives

    Keywords: synergetic control theory, ACAR method, hierarchical method, integral adaptation, crawler platform, DC electric drive

  • Regression model of the ice coverage of the White Sea

    The paper describes the regression model of the change in the ice coverage of the White Sea, obtained on the basis of satellite data of NSIDC. Changes in the ice coverage of the White Sea are mathematically described by a polynomial of the 6th degree, the quality of which is characterized by a coefficient of determination of 0.78. On the basis of the obtained mathematical model, the terms and duration of the phases of the ice regime of the White Sea are established, and also the analysis of the rate of formation and destruction of ice formations is given.

    Keywords: ice coverage, ice phenomena, regression model, White Sea, satellite data of NSIDC

  • Mathematical description of dispersed flows of inhomogeneous liquids

    The article deals with the issues of dispersion of heterogeneous liquids by spray nozzles in order to divide them into components. The influence of various parameters on the size of the droplets obtained is investigated. For the mathematical description the probabilistic approach is applied, which allows to obtain a differential function of the particle size distribution, which can form the basis of the engineering method of calculation of this class of separators. An expression for determining the average value of the angular velocity of the internal flow is compiled. These dependences allow us to calculate the most probable value of the angular velocity corresponding to the decay of complex drops into secondary ones, which are the drops of the initial liquids.

    Keywords: particle, emulsion, non-uniform liquid, droplets, jet, nozzle, velocity, flow, parameter, separator