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scientific edition of Bauman MSTU

SCIENCE & EDUCATION

Bauman Moscow State Technical University.   El № FS 77 - 48211.   ISSN 1994-0408

# 05, May 2013

Machine Building and Engineering Science

Prediction of loss of accuracy in machine tools
# 05, May 2013
DOI: 10.7463/0513.0574593
V.M. Utenkov
This author considers development of techniques for predicting loss of accuracy in machine tools with guideway wear. The problem of obtaining sufficient accuracy for practical estimation of the resource mean value and its possible dispersion was described. The Monte Carlo method, which is currently used for solving this problem, was investigated; its main disadvantages were listed. A basic description of the main stages of the new method for predicting loss of accuracy in machine tools in case of guideway wear was presented with an example of realization of these stages. The author also presents results of predicting loss of accuracy for 16K20F3 and STP-220AP machine tools, which were obtained after cycles of static simulation of wearing process of guideways in case of sufficiently accurate determination of distribution density of resource probability over accuracy parameters.
Mathematical model of production management based on resource-saving principles
# 05, May 2013
DOI: 10.7463/0513.0568317
A.E. Brom, E.V. Eliseeva
Problems of engineering production were studied in this article; it is also shown that the main problem is high resource consumption of products. When solving this problem, it is not enough to rely on existing traditional methods of production management that are used at enterprises. The authors propose a new logistic approach and a mathematical model of production management based on minimization of resource consumption, both from the economic point of view (minimization of the production cost) and the ecological point of view (minimization of manufacturing impact on the environment).
Special features of forecasting and providing quality parameters of products during reconstruction
# 05, May 2013
DOI: 10.7463/0513.0567501
N.A. Yaroslavceva
This article presents an algorithm and a general structural logical model of a technological decision making process on reasonability of reconstruction along with a detailed structural logical model of providing quality of a product being reconstructed. Distinctive features of initial data of a reconstructed product from the data of a product made from scratch are listed. It is emphasized that the main distinctions are: knowledge of remaining life expectancy, data on the input control of the reconstructed product’s condition, heritable parameters and properties, history of loading and damaging and manufacturability of the damaged component. It is shown that formation of consumer properties of a reconstructed product is provided by a complex summing action of transformed external energies of each technological method and processing techniques which are component parts of the reconstruction process.
Analysis of product design with discrete-slot surface structure and their production technology
# 05, May 2013
DOI: 10.7463/0513.0566912
D.V. Ivanov
This article presents a classification of typical circular-shaped details with a iscrete-slot surface structure according to permeability and their geometry of forming. Design variants of these parts are described along with manufacturing methods and application areas. The majority of filtering elements with a discrete-slot surface structure are assembly units which include several interconnected parts. Manufacturing technologies of such filtering elements have a set of restrictions both for productivity and for the guaranteed filtering degree. Bi-rotor technologies of multiblade processing of discrete-slot surface structure that allow to obtain filtering elements as a mono-part with the value of filtering degree equaling 10 micrometers are the most promising in the filtering degree context and efficiency of a production cycle. These technologies allow to obtain the structure which has elastic properties and makes it easier to create adjustable filters with minimal slots width in the compressed condition at the working mode and opening of the filtering element at the regeneration mode.
Justification of elimination of post-weld heat treatment of welded circular butts in a gas pipelines made of X80 steel with wall thickness over 30 mm
# 05, May 2013
DOI: 10.7463/0513.0552162
A.S. Kurkin, S.A. Korolev, P.A. Ponomarev
The authors consider necessity of heat treatment after welding circular butts of thick-walled gas pipelines. They analyzed two main welding technologies of fixed butts in gas pipelines – hand arc welding by an electrode with the basic type of coating, and combined welding. The weld root is produced by machine welding with a solid section wire using the STT method; filling and facing layers of the weld are produced by auto-welding with a flux-cored wire in the mixture of shielding gases using M300-C welding heads. Results of the thermal and stress analysis allow to justify elimination of post-weld heat treatment of circular butts.

Constructional Material Processing in Machine Building

Cutting tool materials for edge tool manufacturing
# 05, May 2013
DOI: 10.7463/0513.0569432
N.N. Zoubkov
This article is based on the review of Russian and foreign periodicals about edge tools published in the last seven years. Existent up-to-date cutting tool materials for edge tools are presented in this work. Their physical and mechanical properties and rational application areas were also described. Special attention was paid to new types of oxide, mixed, whisker-reinforced and silicon nitride cutting ceramics and extra-hard cutting tool materials based on the poly crystalline diamond and cubic boron nitride. Comparison of Russian and foreign trade marks producing cutting tool materials was presented. Classification of extra-hard diamond-based cutting tool materials was also given. Analysis of development prospects of cutting tool materials was carried out.

Power Machine Building, Metallurgical Machine Building and Chemical Engineering

Surface roughness and airtightness of contact sealing devices
# 05, May 2013
DOI: 10.7463/0513.0565094
O.F. Nikitin
The aim of this work is to determine the effect of the value of surface roughness of the contact body on airtightness of contact sealing devices with elastomeric (rubber) rings. Rough edges of two sealing surfaces in contact between two solid surfaces form a system of cavities and capillaries of an arbitrary shape.  Assumed values of roughness are not sufficiently justified. Studies of airtightness considering complex structure of the elastomer O-ring on the compositional level and variety of roughness of the sealing surface were carried out using the bubbling method. The obtained results of the experimental studies justify the values of contact surface roughness used in industry and allow to work out guidelines for choosing values of surface roughness of contact bodies and a compression ratio of elastic rings which provide airtightness.

Transportation, Mining and Construction Machine Building

Simulation of an automotive pneumatic tire interacting with a solid rough supporting surface
# 05, May 2013
DOI: 10.7463/0513.0571409
N.A. Vol'skaya, Ya.Yu. Levenkov, O.A. Rusanov
The authors present a computational model of a pneumatic tubeless tire developed with the use of the finite element method in a physically and geometrically nonlinear formulation. This model takes into account: tire design features and mechanical properties of materials from which it is made; the nature of the tire contact interaction with the supporting rough surface. Adequacy of the tire model was confirmed experimentally. Interaction between road wheels (fitted with a tubeless pneumatic tire) with a supporting surface with irregularities of various shapes and sizes was investigated. The obtained results are intended to clarify the wheeled mover in dynamic models of vehicle for study of oscillation when driving on different types of roads and off-road.
Increase in efficiency of mobile robots by use of an additional source of power supply – flywheel energy storage
# 05, May 2013
DOI: 10.7463/0513.0566233
V.A. Korsunskii
Possibility of application of a flywheel with a drive in ground mobile robots as an auxiliary energy source is considered in this article. Motion modes of the mobile robot with a flywheel accumulating energy during braking are also considered. The material of the rotor’s flywheel was chosen, and its rational form was determined. Energy parameters of the flywheel were calculated. The basic block diagram of the hybrid mobile robot with two energy sources – an electrochemical accumulator and a flywheel –is presented in this article. In order to provide a rational configuration it was proposed to produce a flywheel with an electric motor in the common block.

Mathematics and Mathematical Modeling

Control of chaotic dynamics in the Sprott A System
# 05, May 2013
DOI: 10.7463/0513.0555404
A.V. Kavinov
Since the early nineties, the problem of controlling chaos attracts researches’ attention. The essence of the problem lies in synthesis of control which eliminates chaotic dynamics of a dynamic system. A normally closed system has one or several stable limit cycles. This article deals with the problem of controlling chaos in one of the Sprott systems and also describes the method of elimination of chaotic dynamics by stabilizing a cylindrical invariant sub-manifold in the phase space of the closed system which consists of system’s stable periodic solutions. The system under consideration belongs to the class of affine systems which are not equivalent to a regular system of the canonical form on any subset of the state space. The described method is applicable not only to the specific system in question but may be extended.
Numerical simulation of a robot-assistant operation of sternotomy with a predetermined path
# 05, May 2013
DOI: 10.7463/0513.0599870
A.M. Guskov, M.S. Kuznecova
This article presents a simulation of kinetostatics of a 7-DOF surgical robotic manipulator by the example of sternotomy. Motion of the robot is performed along a predetermined path in the global coordinate system. The numerical simulation was conducted in MATLAB®Robotics Toolbox + Simulink® program package. The same motion was investigated in SolidWorks® for calculating flexibility matrices with the use of the finite-element method. Flexibility matrices for the point of load application were found for 11 successive positions of the robot. Compliance matrices were obtained using ABAQUS CAE® software.

Instrument Engineering, Metrology and Information-Measuring Devices and Systems

Technique of utilizing pulsar processors of frame CCD photodetectors in digital cameras in the modes of time delay and accumulation
# 05, May 2013
DOI: 10.7463/0513.0577481
S.A. Molodyakov
The author considers application of CCD photodetectors designed to work in the frame accumulation mode for usage in the modes of time-delay and accumulation. A set of matrix and linear CCD photodetectors was determined for the problem of constructing digital cameras of pulsar astronomy processors. A special time diagram of control signals of frame CCD photodetectors, which provides special time-delay and integration mode, was proposed. An algorithm for switching modes of CCD photodetector, which takes into account the transition process, was developed. For the first time modes of time-delay and accumulation were implemented for two types of frame CCD photodetectors. Principles of constructing digital cameras with accumulation changeover, frequency control and frame synchronization were derived. Implementation of digital cameras based on a digital signal processor was presented.
Key reasons of abnormal action of ammunition and possible ways of their elimination
# 05, May 2013
DOI: 10.7463/0513.0571026
V.Ya. Kozlov
During ammunition exploitation premature actuation and failures may occur. It’s virtually impossible to fully eliminate such potentially dangerous situations. This article provides an analysis of failure reasons based on the experience of WWII; it also describes fuse modernization after the war. If we speak about artillery ammunition, their abnormal performance can occur at different stages of fuse operating: during service exploitation (as a result of a fall during handling); during loading (wrong loading); during ammunition movement inside the weapon bore (as a consequence of ammunition and fuse defects); when moving after flying out. The last case was considered in detail, and the final results of the research were presented by the example of specific fuses used in the army of Russian Federation.
Method of calculation of electrical admittance of an ultrasonic oscillatory system with biological tissues in COMSOL Multiphysics
# 05, May 2013
DOI: 10.7463/0513.0566872
V.A. Karpuhin, N.V. Vishneva
The article describes a method of calculation of electrical admittance values of a low-frequency ultrasonic oscillatory system with a piezoceramic electro-acoustic transducer in interaction with biological tissues with an allowance for geometry and acoustic characteristics in COMSOL Multiphysics. Using this method, values of natural resonance frequencies of longitudinal oscillations and electrical admittance of the system at various geometry of loading were calculated. Possibilities of using the proposed method and a model with simplified geometry under the assumption of isotropy of the elements materials for calculation of natural resonance frequencies of longitudinal oscillations and electrical admittance of the system were also shown.
Experimental studies of laser fluorescence method for remote control of plant stress situation induced by soil pollution
# 05, May 2013
DOI: 10.7463/0513.0565060
Yu.V. Fedotov, O.A. Bullo, O.A. Matrosova, M.L. Belov, V.A. Gorodnichev
The article describes an experimental setup for studying the laser fluorescence method for control of stress situations for plants. Fluorescence spectra of lawn grass are presented in normal and various stress conditions during fluorescence excitation at the wavelength of 532 nm induced by anthropogenic soil pollution. It is shown that influence of stress factors induced by soil pollution on plants transforms the fluorescence spectrum significantly; these results could be used as a basis for a new laser method for remote control of plants’ condition.
Magnetic bearing on high-temperature superconductors with passive rotor stabilization
# 05, May 2013
DOI: 10.7463/0513.0547989
O.L. Poluschenko, N.A. Nijel'skii, M.A. Sysoev
The authors present a design of a magnetic bearing including ring permanent magnets and high-temperature superconductor (HTS) elements which ensure passive rotor stabilization. Various options of the bearing’s construction were considered; their power and stiffness properties were calculated. The bearing design with bipolar magnetic systems of central and peripheral ring permanent magnets with an opposite magnetization has a maximum load capability. The prototype of the bearing element confirming working-capacity of the proposed bearing construction was manufactured and tested.

Informatics, Computer Science and Management

Investigation of strength of block ciphers based on generalized cellular automata against linear cryptanalysis
# 05, May 2013
DOI: 10.7463/0513.0574231
P.G. Klyucharev
In this paper the authors investigates strength of block ciphers based on generalized cellular automata, against classical linear cryptanalysis. A linear cryptanalysis is one of the main standard techniques for cracking block ciphers. Sufficient condition for strength of this family of ciphers against linear cryptanalysis is the main result of this paper. This condition was used to demonstrate that with an arbitrary graph of a cellular automaton in case of correct selection of a local connecting function and other parameters in order to create ciphers with key length of 128 and 256 bits and block length of 128 bits which couldn’t be cracked by linear cryptanalysis when using 4 rounds and 7 steps of a cellular automaton per round.
Synthesis of orientation mechanisms for the space observatory “Millimetron”. 3. Synthesis of parallel-structure mechanisms for orientation of the space observatory’s antenna
# 05, May 2013
DOI: 10.7463/0513.0571127
Yu.N. Artemenko, V.A. Glazunov, E.E. Sil'vestrov, V.V. Korenovskii, S.M. Demidov
This is the third paper in the series of four works dedicated to design of parallel mechanisms for orientation of the space observatory “Millimetron”». In this work, a method of synthesis of plain six-link mechanisms with three degrees of freedom was proposed. This method takes into account restrictions imposed by requirements to orientation of the space observatory’s antenna. A distinctive feature of the proposed method is decomposition of the synthesized mechanism into two more simple mechanisms – a double pendulum mechanism and a two-beam mechanism. The first mechanism has two degrees of freedom and is designed for maintaining a point in a constant position; the second mechanism’s output link rotates around the first one by a specific angle. All unknown sizes of the mechanism’s links and turning angles were determined in this work. The authors defined a dependence of the turning angle of the output link on the turning angle of the input link of the two-beam mechanism that is a transfer function. Besides, the problem of maintaining an invariable position of the center of mass of the space observatory’s antenna was considered when changing its orientation.
Neural network protection of automated systems’ resources from unauthorized access
# 05, May 2013
DOI: 10.7463/0513.0566210
T.I. Buldakova
The problem of information security in automated systems is considered in this article. Various approaches to restriction of access to information resources were analyzed. An authorization algorithm was developed; the algorithm uses images which a human will be able to recognize but which an intellectual "program robot" will not be able to recognize. Basic types of distortions of reference images were chosen. It is proposed to apply a dynamic neural network as a peculiar filter allowing one to reject images with high probability of recognition. Hopfield’s recurrent network was used in the implementation of the algorithm.
Influence of harmonic noise on the second order phase-lock loop
# 05, May 2013
DOI: 10.7463/0513.0551477
T.G. Aslanov
Influence of harmonic noise on phase-lock loop (PLL) leads to distortion of received information and a loss of PLL stability. This article analyzes effects of harmonic interference on synchronization processes in the second order PLL system. Analysis of signal grabbing and interference capturing cases was carried out in this work; projections of a phase path onto planes, which illustrate the specified modes, were also obtained. By analyzing phase planes, equations of capturing signal and interference were obtained. Dependence diagrams of the signal-to-noise ratio and frequency error are presented along with a bifurcation diagram. Application compares critical values ​​of the PLL parameters obtained by different methods.

Mechanics

Simulation of apparent brightness of the spacecraft “Spectr-R” for planning astrometric observations
# 05, May 2013
DOI: 10.7463/0513.0571011
M.V. Zahvatkin
A radio telescope which is ten meters in diameter was placed on the operational orbit of the artificial Earth satellite on July 18, 2011. This telescope was mounted at spacecraft “Spectr-R” and designed for consistent radio interferometer observations of remote sources together with Earth stations. Success of this scientific project significantly depends on the accuracy of the calculated orbit of the space radio telescope. Astrometric observations are one of many information sources that were used for adjustment of the spacecraft’s orbit. Due to considerable evolution of the orbit observations were taken by means of target indication. Besides the position on the celestial sphere, a predicted value of apparent brightness is also used to identify the object. In case of “Spectr-R” this brightness can vary essentially during the flight. A model for calculation of apparent brightness of the spacecraft “Spectr-R” is presented in this work. Key parameters of this model were obtained from the analysis of telemetric and photometric data.

Optics

Optical losses in silica based fibers within the temperature range from 300 to 1500 K
# 05, May 2013
DOI: 10.7463/0513.0554843
D.A. Dvoreckii, V.F. Hopin, A.N. Gur'yanov, L.K. Denisov, L.D. Ishakova, I.A. Bufetov
In this article optical losses within the temperature range from 300 to 1500 K were investigated in visible and NIR spectral ranges for silica based optical fibers for the first time. It was shown that there is a significant increase in optical losses in the temperature range of 1050 - 1200 º C.  Optical losses reach their maximum at the temperature of 1200 º C at the wavelength of 400 nm; the maximum value for a silica-based optical fiber was approximately 5 dB/m, for a germanosilicate fiber ~ 4 dB / m, for a phosphosilicate fiber ~ 1.5 dB / m and for an aluminosilicate fiber ~ 45 dB / m. By the example of the aluminosilicate fiber it was shown that optical losses in the wavelength range of 380-850 nm could be associated with nano- and microcrystalline inclusions which are formed as a result of fiber annealing.

Power Engineering

Arc-flash processes during single-phase faults in single-phase shielded cables
# 05, May 2013
DOI: 10.7463/0513.0598819
A.A. Antonov, Yu.P. Gusev
The aim of this research is to enhance reliability of power grids with single-phase shielded cables by preventing transition from a single-phase fault to a line-to-line short circuit. Arc-flash processes during a single-phase fault and sheath failure were analyzed in this study. Maximum duration of single-phase faults and its dependence on the method of cable installation were determined. The results of the study are important for estimating failure effects of single-phase faults on cables, for reducing maintenance and restoration costs of cable network. A mathematical simulation of electromagnetic and heat transient processes in a single-phase fault point was carried out using ELCUT software. The accuracy of the model was proved by a number of laboratory experiments with arcing short circuits. It was established that a single-phase fault transforms into a line-to-line short circuit for several seconds in case of a triangle configuration of three single-phase shielded cables with no gap between them. In order to prevent this process it was recommended to apply single-phase shielded cables of 6 – 35 kV to grids with low-resistance neutral grounding and with fast single phase-to-earth faults.

Metallurgical Engineering

Investigation of durability of VKS-7 and VKS-10 steels after vacuum carbonization and vacuum carbonitriding
# 05, May 2013
DOI: 10.7463/0513.0568124
S.A. Gerasimov, L.I. Kuksenova, V.G. Lapteva, R.S. Fahurtdinov, A.E. Smirnov, V.I. Gromov, V.V. Stupnikov
Development of new technologies of thermal and thermochemical treatment, based on the activation of cementation processes and which could provide volume and surface finely-divided or nanostructured state of constructional materials appeared to be a very powerful method to increase the durability of critical machine elements. Results of estimating the durability and micro-hardness of VKS -7 and VKS-10 steels were presented in this article after complex processing which consisted of two stages: 1 – preliminary plastic deformation by means of warm shortening and 2- plasma nitration or vacuum carbonization. Analysis of the relation between hardness and durability was carried out.
Aanalysis of kinetics of phase transformations in non-equilibrium solid solutions of systems such as Fe-2Cr (at.%), Fe-4 Cr (аt.%), Fe-24Cr (аt.%)
# 05, May 2013
DOI: 10.7463/0513.0566894
T.V. Kurihina, V.N. Simonov
In this work the authors calculated phase transformation kinetics in non-equilibrium solid solutions of binary alloys such as Fe-2 Cr (at.%), Fe-4 Cr (at.%), Fe-24Cr (at.%). In the literature [1] there is information on the impact of pre-heat treatment (PHT) on the size of iron nitrides after nitriding. Using the “Termodin” program [2, 3], they calculated cluster sizes, diffusion coefficients at temperatures of isothermal ageing, time of nucleation and time of the growth of the clusters, nucleation rate and growth rate of clusters which were formed at initial stages of decomposition of the supersaturated solid solution. Formation kinetics of a given volume fraction of the σ phase was also calculated. The obtained results allowed to control the structure of alloys, depending on heat treatment
 
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