Modern development of x-ray technology allows to conduct a detailed study of multiphoton processes of absorption and scattering of x-ray photon by deep and subvalent shells of molecular systems in a wide range of energies. The specifics of solving the problem of interaction of an x-ray photon with a multiatomic system requires the use of a single-center approach to the calculation of the electronic States of molecules. The main disadvantage of this approach is a decrease in the accuracy of the calculation of spectroscopic quantities with limited consideration of the terms of the single-center decomposition of the molecular orbital. The paper studies the effect of accounting for higher harmonics of single-center molecular orbital decomposition on the calculation of the energy characteristics of molecular systems. The analysis of the parameters of the single-center decomposition of the functions of the nuclear ligand, depending on its charge. The criteria for inclusion of higher harmonics of single-center decomposition of atomic ligand functions in the molecular orbital are determined. The calculation of energy characteristics is performed on the example of diatomic molecules HF, LiF and BF. The selected series of molecules makes it possible to study the behavior of higher harmonics of the single-center decomposition of the molecular orbital depending on the growth of the atomic ligand charge.
Keywords: molecular orbital, single-center decomposition, higher harmonics, a nuclear ligand, the energy of the electronic state of a diatomic molecule
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
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
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
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
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
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 × 104 (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
The article is devoted to the study of the thyristor regulator of the booster voltage harmonic composition in the mode of longitudinal-transverse regulation. The results of the harmonic analysis of thyristor regulator output voltage , obtained using simulation in the Simulink package, are presented.
Keywords: longitudinal-transverse regulation, thyristor regulator, regulating characteristics, modeling, harmonic analysis, Matlab Simulink
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
The article provides a solution a schedule generation problem for the timber transportation, a description of the problem is given, and a multi-criteria mathematical model is created. It is indicated that the task in question can be assigned to the class of vehicle routing problems in the general formulation of GVRP related to the job-shop scheduling. A hybrid algorithm for solving the problem based on the decomposition method using the simplex method and the genetic algorithm was developed. Conducted testing showed the effectiveness of the developed method on real data of wood harvesting enterprises. The results of numerical methods testing on real data suggest a reduction of the complexes of forest transport machines downtime, and an increase of transported wood volume during the planning period. The scientific results presented in the article were used in the development of a planning and management system «Opti-Wood» developed by Opti-Soft company.
Keywords: wood harvesting, GVRP, optimization, job shop scheduling, operational logistics, genetic algorithm
a method for calculation of electro-hydraulic raspylivatelja liquids. Theoretical dependences of the median diameter of aerosol drops on the fluid flow rate at different number of generator nozzle holes, on its main design parameters are presented.
Keywords: aerosol, dispersion, drop, generator, electrohydraulic atomizer
This scientific study presents an analysis of organizational conflicts, as well as problematic aspects of activity in contemporary realities. The effect of organizational conflict on the effectiveness of an individual is shown. The urgency of researching the problem of the activities of the organization’s employees in the context of organizational conflicts, as well as ways to solve them, is given The analysis of the cognitive model. As factors used to reduce tensions in a team, it was proposed to introduce factors for raising qualifications and organizational culture. These factors will influence the target factor - performance. In the course of simulation modeling, it was found that by carrying out activities to improve the skills of employees, measures to increase the level of organizational culture of employees, the organization seeks to reduce tension in the team and, as a result, there is less staff turnover.
Keywords: simulation modeling, cognitive modeling, functional structural analysis, visual analytics, conflict, organization, model, social tension
Parameters of logging machines are determined by the characteristics of the subject of labour, in particular the size of trees. In stands the sizes of trees vary and have stochastic character. This leads to the difficulty of determining the design tree for the felling machine or calculating the weight of the wood moved by the transport machine. The problem is complicated by the fact that the design of the forest machine should ensure the efficiency of work in different stands. The solution of the problem of determining the calculated characteristics of the subject of labour (characteristics that determine the values of external forces acting on the forest machine) can be based on the analysis of regularities in the structure of stands by thickness. The purpose of this study is to describe a method of constructing stochastic models of the structure of the stand by thickness in the design of forest machines and an example of its application. The proposed method makes it possible to form a stochastic model of the tree stand structure by thickness for the forest area under study and covers procedures from the collection of initial data to the generation of the tree diameter algorithm. Generation algorithms obtained by the method can be used in the development of simulation models for computer experiments aimed at calculating the optimal parameters of forest machines.
Keywords: forest machines designing, stochastic simulation, stand structure by thickness, tree diameter distribution, simulation modeling, computational experiment on the computer
In this article, using the decomposition approximation based on Norton's theorem, the authors present a mathematical model of the distributed information processing system based on the local computer network on file-server architecture with arbitrary functions of the distribution of service time of requests in the network nodes. A conceptual model of an equivalent two-node Queuing network is constructed, in which the first center of the network coincides with the i-th center of the original network with an arbitrary law of distribution of the duration of requests maintenance, and the second (composite), which is the equivalent of the rest of the network, has exponentially distributed service time, which depends on the number of messages in it. The basic mathematical expressions for calculating the intensity of service in the composition center, as well as expressions for calculating the average response time of the system to user requests are also presented.
Keywords: distributed information processing system, file-server architecture, decomposition approximation, queueing network, compositional center, intensity of service, the average response time of the system to user requests, conceptual model, normalizing constan
The exposure of the Aires resonator to electromagnetic radiation with a frequency of 6 GHz is considered. The resonator is a silicon plate with a diameter of 7.4 mm with circular grooves applied by etching. The resulting resonator with a thickness of 0.5 mm contains 4084101 circles of various diameters, which in orthogonal cross sections represent rectangular slits 0.2 μm wide and 0.6 μm deep. It is assumed that the radiation source falls on the resonator evenly from all sides. Thus, we have a radiation source in the form of a hemisphere, the radius of which is substantially larger than the diameter of the resonator (10 m). The intensity of the incident radiation and the frequency of the radiation are assumed to be known. It is necessary to find: the intensity of the radiation at some point in space above the resonator. (Receiver). If the radiation falls on the resonator not in the slot, then a reflection occurs (the angle of incidence equals the angle of reflection). If the radiation falls into the gap, then the reflection does not occur, and absorption occurs. It is assumed that radiation is diffracted on the slits. If you change the time with a certain step, you can calculate the intensity at any point of the receiver at any time. As a result of irradiation of the resonator over its central part, periodic radiation with frequencies of 6.85 GHz and 5.38 GHz is generated. At other frequencies, radiation is generated that is not periodic and is similar to chaotic radiation. The resonator can be considered as a converter of the incident periodic irradiation into other periodic radiations. These periodic emissions have frequencies that can be resonant for some molecules and parts of living organisms that make up the cells. By varying the depth and width of the slits on the resonator, the size of the resonator and other parameters, it is possible to obtain specific frequencies to which particular components of living cells are sensitive. This will allow targeted action on the cells of a living organism.
Keywords: mathematical modeling, structured silicon surface, high-frequency electromagnetic radiation, resonant frequencies, living organisms
The Calculations of the electric network modes are based on the determination of electric power losses during transportation.The calculation methods used are based on the Newton method and the Jacobi matrix. The considered version of the calculation (by a number of transformations) with a small number of iterations allows to obtain the same results as when using the Newton method.
Keywords: matrix of nodal resistances, complex resistivity specific increments, losses of electric energy, compensating devices, algorithm, quadratic model, mathematical model
The approach to construction a computer model of a functional information converter based on element-wise operations with multidimensional tables of numbers is investigated. A numerical decision-making algorithm based on infinite-valued logic was built and verified (in particular, fuzzification, implication, aggregation, defuzzification algorithms). The mathematical, algorithmic and software model of fuzzy decoder of the positional bipolar code in a single-unit one is investigated. The transition from the initial model given in terms of three-valued logic to a similar system having an infinite logical basis is shown. The numerical algorithm has been tested and debugged in the GNU Octave mathematical computation package environment with minimal use of functions from the fuzzy-logic toolkit.
Keywords: decoder, single-unit code, functional converter, infinite-valued logic, t-norm, fuzzification, defizzification, implication, aggregation, three-valued logic, bipolar code
The following work is concentrated on the analysis of dynamic pressure distribution of a brake pad by using ANSYS software. A non-linear contact analysis of brake disc has been performed using Finite Element Method. The finite element model of disc and pads have been developed, and followed by an inclusive simulation of the contact analysis of disc brake system using ANSYS software. A detailed finite element model of a disc brake assembly was developed. Contact analysis was done to determine the pressure distribution, interfacial contact area and normal contact forces under both frictionless (μ=0) and frictional braking conditions. The influence of varying friction coefficients and the brake hydraulic pressure on squeal occurrence is examined. The results illustrated that the contact pressure distribution and the magnitude of normal contact pressures are far greater towards the leading edge of the pads comparing to the trailing edge.
Keywords: метод конечных элементов, распределение давления, контактное давление, шум, тормозная система , нелинейный контактный анализ
The article presents the results of the development of a method for predicting trends in the development of random processes based on ordinal statistics, namely, the median and Hodges-Lehman statistics. The article discusses the proposed method in detail: it provides basic definitions, formulas for the calculation, a detailed description of the algorithm. The algorithm is implemented in the form of a software module that has practical application and can be used to solve problems of forecasting the trend of financial time series. The comparative results of applying the prediction method for the RTS index in the case of the use of the median and the Hodges-Lehmann statistics are given.
Keywords: ordinal statistics, random variable, random process, median, Hodges-Lehman statistics, forecasting, trend, mean square error, mean absolute error
A modification of the generalized algorithm for processing weakly formalized information is considered. It is assumed that in the processing of weakly formalized information it is important to consider external and internal factors. External factors are determined by the characteristics of the incoming information. Internal factors are determined by goals, objectives, methods, etc. The importance of taking into account the latter is that if goals are clear, tasks are set, methods for solving problems and achieving goals are known, then the volume of information being processed is significantly less and the speed of achieving goals is significantly greater. The increase in the speed of processing incoming information is achieved due to the fact that the information processing system adapts to the purpose of information processing. The dominant state of the information processing system is formed taking into account the goals of information processing and the characteristics of the incoming information (the dominant of A. A. Ukhtomsky). Thus, the processing of weakly formalized information from various technical systems allows, taking into account the dominant of A. A. Ukhtomsky, to take into account in the dynamics not only the external impact of the incoming information on the system processing information, but also the state of the information processing system. This system adjusts to the goals of information processing and taking into account the purpose of information processing and the characteristics of the incoming information, the dominant state of the information processing system (dominant) is formed. This allows you to reduce the processing time of incoming information due to the fact that the dominant formed means that the information processing system knows how to process information that has not yet arrived, but it is expected that it will soon go to the sensors of technical systems. In the process of processing the system of processing of weakly formalized information, the dominant may change over time. These changes may be due to changes in both the purpose of collecting the information and the characteristics of the incoming information. Such an approach, which takes into account the dominant of A. A. Ukhtomsky, allows processing large volumes of information in real time and can be used in the development of control systems.
Keywords: information processing, weakly formalized information, algorithm, dominant of A. A. Ukhtomsky, lack of information, control
The article describes in detail such a tool as computer modeling - the concept, its types, the application spectrum and significance. The paper considers the role of computer modelling in the research and analysis of the condition of technical objects on the example of the temperature stabilization system of the cooling element of a thermobox. The construction of a system for stabilizing the thermal mode of a cooling element of a thermobox in the form of a mathematical model is presented, and its numerical analysis is presented in the graphical simulation environment Simulink of the MATLAB software package. According to the study, conclusions were drawn about the importance and effectiveness of computer modelling in the design and evaluation of the behavior of complex systems.
Keywords: computer modelling, mathematical model, experiment, thermobox, electric motor, the Peltier element, temperature, radiator, fan, transients, steady state
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 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
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
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