bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulation of the minimum annual river flows based on the RCP climatic scenario, time horizon up to 2060-2080 and the Kaczawa River
Authors: Kuchar Leszek , Iwanski Slawomir , Jelonek Leszek
Published: November 2018

In this paper a new simulations of minimum daily flow for Kaczawa River a left side tributary of the Odra River in south-west Poland are presented. Generated data were made based on very long series of 35 years of observed data and 24 sites of meteorological stations for south-west Poland gathered from the the Institute of Meteorology and Water Management National Research Institute (IMGW). For the data generation the spatial weather generator SWGEN producing the multisite daily time series was applied. Data were generated for the present (the year 2000 are used as a background) as well for future climate condition for 2060 and 2080 according Representative Concentration Pathways (RCPs) scenarios. The flow simulation in the river catchment is made using MIKE SHE hydrological model. Simulations are done for 2060 and 2080. The large number of new simulated series determined by the lead time, two climate change scenarios (RCP4.5 and RCP6.0), and number of generated years (1000 for each case) is equal to 5000 for a single station. Finally, Lognormal Pdf function for the minimum flow is presented as well probability of exceedance of minimum values.
The influence of the measurement errors on the Brutsaefrt and Nieber analysis of flow recession curves
Authors: Kurnatowski Jacek
Published: November 2018

The paper presents the problem of mathematical form of the hydrological recession in rivers when using conceptual models to describe the catchment behavior. One of the well-known ways of this analysis is the Brutsaert and Nieber method which is based on graphical comparison of flow values and its derivatives. It has been proved that the classical interpretation of these results does not reflect the possible influence of measurement errors which strongly affects the flow derivatives values.
Seasonality and multiannual variability of floods: case study from Eastern Poland
Authors: Siwek Grzegorz
Published: November 2018

Nowadays, under increasing climate change effects on the environment, we can observe increasing number of extreme phenomena, including meteorological and hydrological ones. One of such phenomena are floods. The objective of this article is the assessment of basic flood characteristics seasonality in the annual distribution. Analysis were performed based on time series of daily flow values recorded in the years 1951–2014 in three gauging stations located on rivers in Easter Poland, in upper Wieprz catchment. Floods were defined according to TLM algorithm and were assumed to be all cases of flow occurrence exceeding 10% read from FDC (flow duration curve) (Q10). Seasonality was analysed using Markham’s Seasonality Index and Period of Seasonal Concentration, analysis of autocorrelation function (ACF) as well as proposed by the author Seasonal Winter Floods Index. The distribution of floods during year indicates one flood season in year which occurs in the spring.
Method for calculating the power of a rotor-screw machines
Authors: Lebedev Valeriy A. , Serga Georgy V. , Davydova Irina V. , Atoyan Tatiana V. , Koshlyakova Irina G. , Gordienko Alexander V.
Published: November 2018

Features of parts machining in rotor-screw technological systems are presented. It is shown that the mass of the load, consisting of the processed parts and the granulated working medium, is located along the internal perimeter of the screw rotor asymmetrically to the axis of its rotation. In this regard, there are difficulties in designing the rotor-screw machines drive, and in the rationale for its optimal power. A technique is proposed for calculating the drive power of rotor-screw machines, which makes it possible to carry out a techno-economic assessment study of their applicability for finishing-hardening machining of parts in machinebuilding production. The technique is illustrated on the basis of justifying the drive power of a rotor-screw machine for hardening the details of St3 steel in a screw rotor mounted from 9 octahedra, steel balls are used as a working medium.
Main trends in intensification of rotor-screw processing of parts
Authors: Lebedev Valeriy A. , Serga Georgy V. , Davydova Irina V. , Atoyan Tatiana V. , Koshlyakova Irina G. , Gordienko Alexander V.
Published: November 2018

The ways of productivity increase in details finishing-strengthening processing executed in rotor-screw technological systems are presented. It is shown that the use of rotor-screw machines makes it possible to combine the parts machining using a vibrating field with a large amplitude of oscillations and their transportation in a streamlined form of production organization. Two main directions of rotor-helical processing stimulation are identified: on the basis of structural changes in the screw rotor, as the main working element of the rotor-screw machine and by equipping the screw rotor with activation elements of the process. The classification of screw rotors is presented, which allows purposeful search for the most effective designs of screw rotors and the mechanism is revealed of their influence on the process of parts finishing-hardening processing. Dependence is established for determining the longitudinal movement speed of the parts being processed in the screw rotor. The constructive-technological scheme of the rotor-screw machine is proposed, which allows increase of the productivity of the process and simplification of the design of machines for their implementation, by dismembering the complex screw propulsion of the load mass, which takes place in the screw rotors, into relatively simple in kinematic sense motions. The technological possibilities of rotor-screw processing application for finishing-strengthening operations are presented.
Stability of a composite thick plate with an inhomogeneous field of initial stresses
Authors: Eremeev Vadim V. , Shubchinskaya Natalia Y. , Ivashchenko Denis V. , Minko Vsevolod A.
Published: November 2018

We discuss the linear stability analysis for a rectangular twolayered elastic plate. Each layer of the plate was obtained due to inflation of an annular wedge of a cylinder. As a result, in the plate there are initial stresses. The main aim of the paper is to analyse the influence of the initial stresses on the buckling. Here we use the 3D nonlinear elasticity technique. The linearized boundary-value problem is derived and its non-trivial solutions were obtained.
Dynamic models of cultivator spring tine performance
Authors: Polushkin Oleg A. , Ignatenko Vitalyi I. , Ignatenko Ivan V. , Vyalikov Ivan L. , Bogdanovich Vitaliy P.
Published: November 2018

The article presents results of spring-tine cultivator blade movement modeling. The basic equation of terraelasticity is taken as the initial one. The new model takes into account the spring tine configuration and the vibration mode. It is noted that the model becomes multifrequent. The field reserach confirmed multifrequency and mixed nature of the spring tine vibration spectrum. It is found that the frequency spectrum with technologically relevant vibration accelerations can be more than 1000 Hz. The authors make a conclusion that it is necessary to use high frequencies to improve the quality of spring-tine cultivator blade performance.
Influence of irradiation on the dynamics of changes in the mechanical properties of the nuclear reactor vessel
Authors: Bakhracheva Yulia S.
Published: November 2018

Nuclear power plants are important generating units of the energy system worldwide. In the normal mode, nuclear power plants are absolutely safe, but emergency systems with radiation emissions have a devastating impact on the environment and public health. Despite the introduction of technologies and automatic monitoring systems, the threat of a potentially dangerous situation remains. The reactor vessel is the main object of activities to ensure the safety of nuclear power plants. One of the problems of ensuring the safety of nuclear power plant reactor vessels is the prediction of the level of crack resistance of reactor steels. The paper shows the possibility of estimating the neutron irradiation level on the nature of the temperature dependence of KIC. The prediction of the influence of radiation damage on the fracture toughness of the reactor steel can be obtained on the basis of the results of tests of small cylindrical samples with annular notches.
Technological effect of processing with the organic granular media flows
Authors: Krupenya Yevgeniy Y. , Boyko Marina A. , Shishkina Antonina P.
Published: November 2018

There has been carried out the analysis of approaches how to model vibrational processing by granulated media. The vibroprocessing model has been developed, that provides effective parts’ surfaces finishing work with granules of stone organic media initially based on the approach of energy impact of the granule flow on the processed surface. Specific volumetric metal scrap has been used as the main characteristic of processing with organic media its physical aim is increase rate of thickness of the material removed from the surface in the frames of definite velocity and pressure of the media. It is shown that metal scrap depends on media flow velocity, granular media height of the loading column, conditions that form stationary circulation motion of the media. Taking into account the analysis of experimental studies results of amplitude-frequency characteristics influence on the metal scrap during of abrasive granules vibroprocessing, there has been disclosed some certain dependence of the specific volume metal scrap while organic media processing, considering threshold amplitude and frequency of oscillations of the working tank that made it possible to observe the effect of surface treatment is. The established dependence describing the effective vibroprocessing conditions with stone organic media that was achieved due to experimental data which allows to assume validity of the obtained model.
Numerical cam profile design with tappet constant speed section in internal combustion engine valve gear and fuel system
Authors: Vasilyev Alexander , Bakhracheva Yulia
Published: November 2018

In modern internal combustion engines the drive of valves of the mechanism of gas distribution and a plunger of the fuel pump of high pressure is carried out by the cam mechanism. The functional requirement imposed to gas distribution mechanism cams is receiving the greatest valve “time-section” when ensuring working capacity and reliability of the valvate drive. One of the main directions of improvement of fuel pumps of high pressure of diesel engines is increase in the maximum pressure of injection. In this work it is offered to improve a numerical method by imposition of the restriction on the first derivative of movement of the pusher on a cam angle of rotation, that is a pusher speed analog. This restriction allows to receive a cam with the site of constant maximum speed of the pusher. It allows to increase the maximum pressure of injection.
Effects of deformation dynamics in problems of heavy transport
Authors: Nosachev Sergei V. , Chuveiko Mikhail V. , Zhukova Maria Yu. , Kuzin Gennadiy A. , Khozyaev Igor A.
Published: November 2018

The problem of the appearance of the sliding effect in the wheel-road contact in railway transport is considered. It is known that the sliding effect accompanying the rolling process of the wheel is explained by two fundamentally different processes: sliding caused by the loss of traction of the wheel to the road surface and, so-called, deformation sliding. The phenomenon of deformation sliding is not related to loss of adhesion and can occur even when the wheel is fully engaged with the road surface. In fact, the deformation sliding is due to the non-trivial deformation dynamics of the rim of the wheel and the rail which results in an actual reduction or increase in the speed of the translational motion of the wheel while maintaining its angular frequency of rotation. Due to the fact that the phenomenon of loss of adhesion, as well as the accompanying sliding, has been studied in some detail, in this paper attention is focused specifically on the deformation component of the sliding process.
The effect of parametric excitation on a dynamic system of cutting process
Authors: Tung Pham Dinh , Ahn Nguyen Dong
Published: November 2018

The problem of ensuring stability of movements of the tool about workpiece taking into account parametric self-excitation is considered. The factors causing periodic changes of parameters in dynamic system when cutting are analyzed. They are connected with spatial anisotropy of properties of elasticity in a subsystem of the processed workpiece with allowance variations on workpiece rotation perimeter, with kinematic perturbation from mechanical part of drives of executive elements of the machine, with periodic processes in a cutting zone. The generalized dynamic model of system with periodically changing parameters is given. Influence of periodically changing parameters on stability of trajectories is studied. The features of loss of stability specific to dynamic systems of cutting are disclosed. In particular, it is shown that due to parametrical effects with increasing cutting speed at increase of rotational frequency of spindle there is always a critical frequency at which the system loses stability.
Study of the industrial contaminations containing hydrocarbon components and their effect on correlation of protective properties of textiles for clothes
Authors: Cherunova Irina , Yakovleva Elena , Stefanova Ekaterina
Published: November 2018

The article represents trends and results of world investigations for safety of textile materials for humans and environment. The algorithm for identification of potential influence vector of chemical emissions from textile and the environmentally aimed methods based on the alternative chemical substances for textile wet processing were presented. Using the procedure for oleophobic effect determination, the oil resistance levels of a number of modern fabrics for clothes were established. The experimental research results of the oil products concentration in the textile materials after chemical treatment based on the method of the capillary gas chromatography were presented. It was found out that hydrocarbons from C14H30 Tetradecane to С36Н74 Hexatriacontane are the main components with high level of contaminants concentration. The average values of hydrocarbon concentration on the cleaned up samples for the main areas of the clothe surface were determined. Accumulation of residual contaminations, based on saturated hydrocarbons (С17Н36 – С25Н52 block) and related special-purpose clothes areas, was identified. Recommendations for target-oriented correlation of the clothes protective properties were proposed. UWO (unified work order). The research was made in Don State Technical University within the framework of State Assignment of the Ministry of education and science of Russia under the project 11.9194.2017/BCh.
Optimization of parameters of the electromechanical converter with a discrete secondary part
Authors: Kuimov Denis , Pavlenko Alexandr , Minkin Maksim
Published: November 2018

The algorithm of multicriteria optimization of a tooth zone of the electromechanical converter with a discrete secondary part realized on the basis of application of the program Ansys complex is offered. The optimum geometry of a tooth zone of the inductor of the electromechanical converter with a discrete secondary part on condition of achievement of the greatest possible value of the electromagnetic effort operating on ferromagnetic elements is defined. As a method of optimization the stochastic Monte Carlo method has been used.
A combined application of the boundary element method and Lobatto time-stepping procedure in 3-D partially saturated poroelastic problems
Authors: Petrov Andrey I. , Belov Aleksandr A.
Published: November 2018

The report presents a modification of a time-step scheme on the nodes of Runge-Kutta methods for solving 3-D dynamic poroelastic problems using the boundary element method. To describe poroelastic medium, Biot’s mathematical model of a material is employed, in which solid phase and two fluid phases, filling the pores -liquid and gas, are discerned. 2- and 3-stage Lobatto methods were chosen as a particular example of Runge-Kutta methods. A comparison of the results obtained using the Lobatto method and the Euler method is presented.
Development of the Paris-Erdogan model for the quantitative evaluation of the wear resistance of materials under dynamic contact with a discrete liquid-drop flow
Authors: Varavka Valery N. , Kudryakov Oleg V. , Bronnikova Natalia I. , Zabiyaka Igor Yu. , Rubanov Vladilen V.
Published: November 2018

The known fatigue model of Paris-Erdogan was first used for conditions of multi-cycle water-drop impacts with a metallic surface. The model is supplemented by the structure-dependent characteristics of the material. Experimental data providing correctness of model application is presented. The applied problem of quantitative evaluation of the material durability in the conditions of the droplet impact and comparison of materials of different structural classes was solved in the work without costly bench tests.
Features of destruction of a ferrite-martensitic composite
Authors: Pustovoit Viktor N. , Duka Valentina V. , Dolgachev Yuri V. , Aref’eva Ludmila P. , Fedosov Vladislav V. , Salynskih Viktoria M.
Published: November 2018

The behavior of a crack in steel with the structure of a ferriticmartensitic composite is studied. The modes of heat treatment for obtaining a composite structure with alternating layers of ferrite and martensite are given. The kinetics of crack development during cyclic tests was studied. The obtained data show that the rate of development of the crack in the material with the structure of the composite is substantially lower than for the usual sorbite structure. It is shown that the frontal growth of the crack in the composite is carried out with “stops”, on which the matrix deforms and its stratification occurs in the direction normal to the front of the crack motion.
Microarc surface alloying of tool steels
Authors: Stepanov Makar S. , Dombrovskii Yuri M. , Davidyan Levon V.
Published: November 2018

A new method of accelerating of steel diffusion saturation during thermo-chemical treatment – microarc surface alloying is proposed. The steel product is placed in a metal container filled with coal powder, and heated by passing an electric current. Powder having microarcs, which are concentrated around the surface of the product with the formation of zones of local gas discharge. This significantly speeds up the diffusion saturation. After carburizing of steel 20Cr13 is formed a diffusion layer thickness of 13-15 μm microhardness of 10.5 to 12.5 HPa, located below the eutectoid area a thickness of 300 μm and a hardness of 6.5 GPA. After boriding of steel Cr12V1 after standard heat treatment, the surface layer with a thickness of 170-180 μm consists of a base with microhardness of 9.3-9.6 GPA with inclusions of microhardness of 14.5-15.0 GPA. After boriding of steel 5CrNiMo formed a layer thickness of 250-260 μm with a composite structure consisting of sections of the eutectoid structure of microhardness of 7.0-8.0 GPA, surrounded by boride eutectic microhardness 12.0-12.5 GPA. The composite structure provides the combination of very hard boride eutectic and eutectoid plastic mixture. After boriding of steel W6Mo5Co5 after standard heat treatment, the surface layer thickness of 230-240 μm consists of a base of microhardness 11,0-11,2 GPA with inclusions of microhardness 13,5-14,5 GPA. Given the high intensity of diffusion saturation, microarc surface alloying is recommended for surface hardening of tool steels.
Properties of biocomposite on the “bone-tocarbon nano implant” border
Authors: Golubev George Sh. , Rodin Michael B. , Irkha Vladimir A.
Published: November 2018

Novice carbon nanostructural material was investigated to estimate its integration to the bone tissue. Wedge osteotomy of a femur bone performed in experimental circumstance on 26 white rats (control=6, experiment=21). Wedge-shaped (h=4 mm, r=3 mm, α=12) implants were crafted from carbon nano-structural material and used to fill bone’s defect. Rats withdrove from the experiment in 3 months. Mechanical properties of the “bone-wedge-bone” block evaluated by the 3-point bending test. Field emission scanning electron microscope used to investigate biocomposite at the bone-to-implant border. The microelements distribution in the samples measured with energy dispersive X-ray analysis. Biomechanical properties of bone-to-implant biocomposite depend on clinical features of consolidation. Anyway, the toughness (T) of bone-to-implant zone is worse than bone-to-bone regenerate significantly (Tcontr = 56.97 MPa, Texp = 47.68 Mpa, Welsh p-value = 2.689e-07). No Ca, or P reveals in the body of implants. The quality and the thickness of the biocomposite on the bone-to-implant border predetermine clinical results of bone substitution. The absence of microelements inside the body of implants confirms that the implant structure is too subtle. Increasing porosity of material and creation of transverse channels can improve bone conduction and scaffold quality of carbon nano-implants.
Synthesis of bioactive materials for implants in the system Ca3(PO4)2-Ca2GeO4
Authors: Mukhanova Elizaveta A. , Vetokhin Vyacheslav G. , Rybalkin Alexander A.
Published: November 2018

Various modifications of Ge-substituted calcium phosphates were obtained using solid-phase synthesis, co-precipitation in solution, and combustion synthesis. Structural changes in the synthesis process are established using X-ray diffraction. The biological activity of the obtained samples in model fluids was estimated. It has been found that the synthesis method can lead to various structural modifications of calcium phosphate, which is a significant refinement to the phase diagram of the Ca3(PO4)2- Ca2GeO4system described in the literature.
A penny-shaped crack in a functionally graded layer between two half-spaces with different elastic properties
Authors: Krenev Leonid I.
Published: November 2018

The axisymmetric static problem is considered on a pennyshaped mode I crack in an elastic inhomogeneous isotropic space. Young’s modulus of the elastic space material is non-symmetrical with respect to the crack. The procedure is proposed for approximate problem solution and determination of the stress intensity factor.
The study of the tribological, thermal and physical properties of phenylone C-2 based composites containing nonstoichiometric molybdenum and tungsten oxides
Authors: Karpenko Ksenija I. , Novikov Evgeniy S. , Danilchenko Sergey A. , Avilov Viktor V.
Published: November 2018

The given paper lays bare the preparation and study of multifunctional tribocomposites with matrix based on Phenylone C-2 and the antifriction fillers. Besides, it contains a comparative evaluation of physical, mechanical, tribological and thermophysical properties of multifunctional tribocomposites to assess the effect of nanodimensional fillers.
Dynamics of a vibration system, taking into account the hereditary type friction and the mobility of a vibration limiter
Authors: Metrikin Vladimir S. , Igumnov Leonid A. , Zaitsev Mikhail V. , Boev Aleksandr V.
Published: November 2018

The paper investigates the dynamics of some vibration systems taking into account the hereditary-type dry friction and mobility of a vibration limiter. The interaction of the vibration limiter and the vibration system occurs either according to Newton’s hypothesis (an absolutely rigid limiter) or softly (the limiter is mobile). A general mathematical model (MM) of systems has been developed, which is highly non-linear nonautonomous system with variable structure. A numerical-analytical approach using the mathematical apparatus of the point mapping method is implemented to study the dynamics of the MM. The peculiarity in the research approach is that the point mapping is not formed by the classical method (mappings of the Poincaré surface into itself), but by the duration of relative rest of the vibration system, which greatly facilitated the process of point mapping and its detailed study. The presence of floating boundaries of slip-motion plates required the creation of an original approach in constructing point mapping and interpreting the results obtained. The structure of the phase portrait of the MM as a function of the characteristics of the sliding and state friction forces, as well as on the type and position of the limiter was studied using the developed research methodology and the created software product. Based on the character of changes in bifurcation diagrams, it was possible to determine the main laws of changes in the motion regimes (occurrence of random complexity via the period possible transfer to chaos doubling process) when changing the parameters of the vibration system (amplitude and frequency of periodic action, the form of the functional dependence describing the change in the coefficient of friction of relative rest. Analytical results with and without a vibration limiter are compared.
Numerical analysis of influence of length of the working part of specimen on dynamic diagrams of constructional materials obtained by the Kolsky method
Authors: Konstantinov Alexander Yu. , Basalin Artem V. , Gonov Mikhail E. , Filippov Andrey R.
Published: November 2018

It is known that experiments with intensive dynamic influences and high-speed deformation of specimens under tension are important in the analysis of deformations and strength of structures and their elements. The most reasonable and widely used method for obtaining dynamic stressstrain curves, characteristics of ultimate strength and deformations is the modified Kolsky method. It should be noted a small number of publications on the analysis of the influence of fillets and the length of the working part of the specimen on the most important mechanical characteristics obtained by this method. This work is aimed at increasing knowledge in this area. By numerical and experimental analysis it was established that when the working part of the specimen has a length of 5 mm, then the uniformity and one-dimensionality of the stressed state are seriously violated. When choosing the length of the specimen in the Kolsky method, there are important limitations: the length of the specimen must be much smaller than the length of the loading pulse. Therefore, in this study, two specimen lengths of 10 and 15 mm were analyzed. In this paper, we give experimental and calculated diagrams and their comparison with each other. It was shown, that for the above-mentioned lengths, the homogeneity and one-dimensionality of the stressed state is substantially improved.
Experimental complexes for investigation of behavior of materials at a strain rate of 5·102÷105 s-1
Authors: Bragov Anatoly M. , Konstantinov Alexander Y. , Lomunov Andrei K. , Yuzhina Tatyana N. , Filippov Andrey R.
Published: November 2018

A description of experimental complexes, methodological and hardware means for determining the mechanical properties of materials under high-speed deformation and fracture is given in the report. Determination of mechanical properties in the strain rate range 5•102÷103 s-1 is the first direction of work in the laboratory of “Dynamic Materials Testing”. These tests are done using automated complexes based on the Kolsky method and its modifications for compression, tension and shearing. It is also possible to determine the fracture toughness, the characteristics of dynamic crack resistance, as well as to obtain stressstrain curves of low-density materials under uniaxial strain. Original gas guns with a caliber of 10, 20 and 57 mm are used for creation a dynamic load. The study of the behavior of materials at strain rates of 105 s-1 and higher is the second direction of work. In this case, the methods of a planewave shock experiment based on gas guns of 57 and 85 mm caliber are used. Manganine and dielectric pressure sensors, as well as laser interferometry are used for measuring the parameters of elastoplastic waves and for determining such important characteristics as impact compressibility, Hugoniot yield strength, spall strength.
Computational model of the deformation of graded wedge with complicated structure
Authors: Trubchik Irina S. , Evich Ludmila N. , Ladosha Evgenii N.
Published: November 2018

As a computational model of deformation of wedge-shaped gradient coatings lying on a non-deformable base, we propose a solution of the contact problem for a wedge non-uniform in thickness rigidly fixed on the lower face. A closed analytic solution of the contact problem is obtained for the case of elastic moduli (Young’s modulus, Poisson’s ratio, shear modulus), which is a continuous differentiable function with respect to the angular coordinate. The influence of the gradient of the wedge on the distribution of contact stresses under the stamp is illustrated. The problem is posed in connection with the need to predict the phenomenon of delamination of modern coatings of a complex structure from a nondeformable substrate.
On a method for determination of Poisson’s ratio and Young modulus of a material
Authors: Zelentsov Vladimir B. , Sadyrin Evgeniy V. , Sukiyazov Aleksandr G. , Shubchinskaya Nataliya Yu.
Published: November 2018

On the base of modernized NanoTest 600 Platform 3 indentation method is proposed to determine elastic parameters – Poisson’s ratio and Young’s modulus – of a material while loading in an elastic region. The experiment is based on procedure: lateral surface of indenter tip with the shape of parabolic cylinder penetrates into the specimen. NanoTest 600 was equipped by additional optics, backlight and device for spatial orientation of the specimen. This modernization allows to control the process of the indenter penetration both along its length and from the edges, so that one can observe and measure the width of the contact area and control the depth of the indentation area in a sample material. Mathematical modeling of the indentation process was conducted within the framework of plane theory of elasticity. This required solution of the contact problem on indentation of a rigid indenter with a parabolic shape into an elastic strip coupled with a non-deformable substrate. The fulfilment of condition of zeroing the contact stresses at the edges of the indenter with a known width of the contact area allows to determine the Poisson’s ratio, and condition of static equilibrium of the contact problem helps to find Young’s modulus of a strip material.
Investigation of the processes of separation and spread of welding aerosols taking into account various types of heat and mass transfer to ensure safe welding conditions in confined space
Authors: Bulygin Yuriy I. , Rogozin Dmitriy V. , Kuptsova Irina S. , Azimova Natalia N. , Khlystunov Viktor F.
Published: November 2018

Russia has a well-developed network of pipeline transport. Its installation and repair is carried out using arc welding. Typically, arc welding is associated with harmful sprays of aerosols, especially in cases where flux cored wires are used for welding. Given the difficult weather conditions in the pipeline construction area, the use of shelters (booths, tents) is considered as an obligatory requirement for the conditions of welding on the installation. The work is aimed at theoretical substantiation of methods for controlling excessive pollution of the environment with welding aerosols and gases in confined spaces, which will allow creating technologies for designing systems and means of dust and heat protection for welders working in the installation conditions.
Research of nanoscale titanium carbides influence on the structure and properties of weld metal in automatic submerged arc welding
Authors: Kobernik Nikolay V. , Pankratov Alexander S.
Published: November 2018

The influence of nanoscale refractory titanium carbide particles on the structure and properties of weld metal in automatic submerged arc welding is considered. Composite granules based on nickel were used to introduce the compound into the composition of the weld pool. Two schemes for introducing granules into the weld pool were tested, characterized by different temperature conditions: to the head part of the welding pool with the help of “ligature” and to the tail section with the help of additional filler wire. The prospects of introducing nano-sized titanium carbide into the tail part of the weld pool as part of a flux-cored wire are shown. With this method, the structure of the weld metal is observed to modify: the average size of the primary crystals of the weld metal is reduced by almost 50%. At the same time, the value of the toughness of the weld metal increases: the average value of this index increases by 36%. When titanium carbide is introduced as part of the “ligature” into the head of the weld pool, despite the effect of modifying (reducing the width of the primary crystals by 30%), the average value of the toughness of the weld metal decreases.
Dynamics of thermoelastic frictional wear of a coating with piezoelectric interlayer
Authors: Lapina Polina A. , Mitrin Boris I. , Kuznetsova Tatyana A. , Lapitskaya Vasilina A.
Published: November 2018

To study dynamics of a coating wear, this paper deals with an uncoupled thermoelastic contact problem on sliding of a rigid punch over the surface of a thermoelastic coating bonded to an electroelastic interlayer, which itself is bonded to an undeformable substrate. Friction, frictional heating and coating wear on the contact is taken into account. The problem solution was constructed by the Laplace integral transform method and was obtained in the form of the Laplace convolutions. Based on the obtained expressions it is possible to develop technique for monitoring of a coating wear on a sliding contact through values of electric current arising in the piezoelectric interlayer.
Using the SimInTech dynamic modeling environment to build and check the operation of automation systems
Authors: Abalov Albert A. , Nosachev Sergey V. , Zharov Viktor P. , Minko Vsevolod A.
Published: November 2018

This article is devoted to the description of the simulation process of automatic control systems using the SimInTech dynamic modeling environment. Here is given a brief his-tory of the development of the software package from simulation to end-to-end process of creating the automatic control systems. Also describes the purpose of mathematical modeling of automatic control systems. The article presents basic information on modeling and development process in the environment. The example detailed step by step creation of an automation scheme is considered. The advantages and disadvantages of the SimInTech environment are shown in comparison with the competitive environment of Simulink.
Waveguide analysis for ultrasonic medical instruments (comparison of different methods)
Authors: Grigoryev Yuri V. , Aung Pyae Phyo
Published: November 2018

Transition matrices are derived on the basis of some analytical solutions for a number of waveguides. Initial parameters method is used to analyze the waveguide longitudinal oscillations. This paper contains a comparative analysis of different types of concentrators. The waveguide design scheme presents a straight bar of variable cross-section with different boundary conditions. For given concentrator arrangements, the amplitude axial displacements and longitudinal forces in the ultrasonic medical instrument (UMI) are calculated for a certain excitation frequency. Numerical method for calculation of eigenfrequencies and eigenmodes of the ultrasonic medical instrument (UMI) waveguide is presented. Analysis of the cantilever straight-line concentrator based on the methods of transition matrices and numerical integration by the Runge-Kutta method are under comparison. Sufficient agreement of the results is demonstrated.
Feed-forward control of a building’s heating system
Authors: Fomin Valery V.
Published: November 2018

In the heating of buildings during positive dynamics of weather conditions a problem is encountered of air temperature rise in the rooms of the building. Solution of the problem given the buildings are equipped with heating system controllers is a practical task using update algorithms in the operation of controllers. The proposed method offers an option of a heating system control algorithm to attain stable temperatures in the rooms of the building.
Optimization of electronic document management systems by means of encoding and visualization of stored data in the integrated development environment
Authors: Poskonin Mikhail V. , Kalinin Andrey O. , Kovalev Igor V. , Saramud Mikhail V.
Published: November 2018

The article considers the issue of storage, cataloging and transfer of documentation within the electronic document management system (EDMS). Modern document management solutions can be considered as the intersection of traditional and digital technologies, in particular, the storage of software code on paper. The very storage of program code in paper version implies a large archive for data storage, which includes modifications when versions of the program code are updated. Graphical ways of storing large amounts of data have been known for a long time, but they usually use a long procedure for restoring the original information and exclude recovery from paper or are significantly limited in the amount of stored data. As one of the elements of the composite electronic document management system it is proposed to use the method of graphical encoding of information (QR-code generation technology), which will increase the resistance to unauthorized modification of the program code, simplify the procedure for storing, identifying and verifying information. As an elementary block of information, it is intended to use a separate software module responsible for one of the subprograms in the RTOS environment. The proposed algorithm for storing and transferring information implies its compression by software, encryption and transmission. The article compares various compression algorithms and their efficiency. The presence of a cataloguer in each graphic element allows for quick search, comparison and verification of blocks.
Modeling of production and destruction processes in coastal systems on a supercomputer
Authors: Nikitina Alla V. , Kravchenko Ludmila , Semenov Ilya , Belova Yuliya , Semenyakina Alena
Published: November 2018

The paper covers the development and research mathematical model of production and destruction processes in coastal system, based on the modern information technologies and computational methods to improve the accuracy of predictive modelling the ecological situations in waters during the summer. The model takes into account following: the movement of water flow; microturbulent diffusion; gravitational settling of pollutants; nonlinear interaction of plankton populations; the impact of salinity, temperature, as well as the pollution entrance and deposition from river flows and air. The scheme with weights was proposed for discretization of the developed model, that allowed significantly reduce the error and the computational time. Practical significance of the work is that the proposed model was software implemented; the limits and prospects of its use were defined. On the basis of a supercomputer, the experimental software was designed for mathematical modelling of possible development scenarios of the ecosystems of coastal waters on the example of the Azov Sea in the summer period, taking into account the influence of environment. Parallel implementation was performed using the decomposition methods for computationally labours diffusion-convection problems taking into account the architecture and parameters of multiprocessor computer system.
The difference scheme for the two-dimensional convection-diffusion problem for large peclet numbers
Authors: Sukhinov Alexander I. , Chistyakov Alexander E. , Belova Yulia V.
Published: November 2018

The purpose of this work is the development of a difference scheme for the solution of convection-diffusion problem at high Peclet numbers (Pe>2). In accordance with this purpose the following problems were solved: difference scheme for convection is built, comparison with the existing schemes is carried out; conditions for stability of the proposed difference scheme are obtained. Solutions of the convection-diffusion equation on the basis of the proposed difference scheme at various Peclet numbers are obtained.
Synthesis of intelligent fuzzy control in the space of bounded piecewise-continuous functions based on the combined maximum principle
Authors: Kostoglotov Andrey A. , Lazarnko Sergey V. , Nikitin Igor A.
Published: November 2018

It is shown that the solution of the problem of control synthesis using the Hamilton-Ostrogradskii principle leads to a variational inequality, from which the conditions for the maximum of the the generalized power function in the space of bounded piecewise continuous functions follow. It allows to find a feedback structure up to a synthesis function. Using the methods of the structure construction the nonlinear structures of the relay and continuous control laws are obtained. The proposed control method allows to avoid the mode with frequented switching. It consists of the following two stages. At the first stage, the control object is brought into the vicinity of the terminal state using the relay control law. In the second stage, the quasi-optimal continuous control is used. The uncertainty of the transition area size is resolved using fuzzy logic. The efficiency of the intelligent controls is demonstrated by the example of mathematical modeling of the system dynamics.
Direct incentive-compatible mechanism for innovator-investor bargain in an innovation investment system
Authors: Gurtuev Alim
Published: November 2018

The functioning of the system of innovation investment, where an objective evaluation of an investment project containing new knowledge is impossible both for the investor and the innovator, currently is a matter of great interest. While for traditional industries, the use of statistical data is a satisfactory approach to the problem of uncertainty, for innovation projects this method isn’t applicable due to the natural absence of a valid statistical base. The practice shows that the empirical mechanisms used for innovation projects are rarely used for investing in traditional industries and vice versa. In this connection, there arises the problem of development an effective mechanism for financing innovation projects. We developed such a mechanism for the innovator-investor system in the form of a Bayesian non-cooperative repeating game with recalculated payments. The equilibrium parameters for any period of the given game are obtained. It is shown that, depending on the a priori estimates of the type of project, four different equilibria are possible in any particular period of that game. Therefore, using the strategy of adjusting a priori estimates of the investor and innovator on the basis of the Regret Matching rule, equilibrium for this finite Bayesian game is obtained.
Study of methods for dimension reduction of complex dynamic linear systems models
Authors: Manatskov Yuriy M. , Bertram Torsten , Shaykhutdinov Danil V. , Gorbatenko Nikolay I.
Published: November 2018

Complex dynamic linear systems of equations are solved by numerical iterative methods, which need much computation and are timeconsuming ones, and the optimization stage requires repeated solution of these equation systems that increases the time on development. To shorten the computation time, various methods can be applied, among them preliminary (estimated) calculation or oversimple models calculation, however, while testing and optimizing the full model is used. Reduced order models are very popular in solving this problem. The main idea of a reduced order model is to find a simplified model that may reflect the required properties of the original model as accurately as possible. There are many methods for the model order reduction, which have their advantages and disadvantages. In this article, a method based on Krylov subspaces and SVD methods is considered. A numerical experiments is given.
Ways of intensification of the process of moistening the grain before grinding
Authors: Larina Lyudmila V. , Rusljakov Dmitry V. , Tupolski Tatiana I. , Tikhonova Olga B.
Published: November 2018

The aim of this study is substantiation of ways of reducing the time required to process pre-wetting the grain before peeling, flattening, grinding [1]. A method of moistening the grain before grinding with preevacuation of its interior microvoids through the porous shell provides moisture transfer in the liquid phase. This moisture transfer requires the subsequent application of excess pressure to the penetration of moisture to the core of the grain and subsequent long-term otvalivayas grain. To significantly reduce the time of wetting is proposed to use a moisture transfer with effusion in the form of steam produced at low pressure (vacuum), then the guaranteed condensation in micropolitan porous shell of the grain. Study of intensity of moisture transport in accordance with the changes in concentrations of vapour along the length of the capillary in a vacuum proved the possibility of intensifying the process of moistening the grain before grinding.
Modeling of capillary-sorption process steam condensation in the system of microcapillaries of grain shells
Authors: Larina Lyudmila V. , Rusljakov Dmitry V. , Tikhonova Olga B.
Published: November 2018

The aim of this study is to simulate the capillary-sorption process of steam condensation in the system of microcapillaries of grain shells [1]. Modeling of the processes of intensive moisture transfer during drying of a number of materials was considered in [2,3]. In order to significantly reduce the time of moistening, moisture transfer by effusion is considered in the form of steam produced at low pressure (vacuum) with its further guaranteed condensation in micro-cavities (microcapillaries) of a porous shell of grain [4]. Study of intensity of moisture transport in accordance with the changes in concentrations of vapour along the length of the capillary in a vacuum proved the possibility of intensifying the process of moistening the grain before grinding. The obtained mathematical model will allow to calculate the values of the theoretical weight gain of moisture in microcapillaries depending on the parameters and the time of vacuum-sorption moisture.
Research the textures synthesis method based on the neural network
Authors: Ibadov Ragim R. , Ibadov Samir R. , Gapon Nikolay V. , Tokareva Olay A. , Alepko Andrei V.
Published: November 2018

The article presents the urgency of developing a method for removing clouds. The object of the study are methods of detecting objects on images, in particular, cloud images, to exclude areas containing clouds from subsequent processing and analysis. The algorithm of selection and removal of cloud images is investigated, and its software implementation is developed. On the test example, the quality of the implemented algorithm was evaluated.
Restoration of the lost volume of bone tissue with use data of the computed tomography
Authors: Semenishchev Evgenii , Zelensky Alexandr , Tolstova Irina , Tokareva Svetlana , Frants Vladimir , Nadykto Alexey
Published: November 2018

The paper deals with the issue of bone tissue restoration. To assist the specialist, we developed the SmartAssistantConstructor software package. The recovery process is based on finding a mirror copy of a piece of bone tissue. The article describes the algorithm for finding the missing part of the bone. The paper shows examples of this operation.