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scientific edition of Bauman MSTU

SCIENCE & EDUCATION

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

# 12, December 2013

Machine Building and Engineering Science

Method for determining modes of jet-dynamic flushing of parts with blind holes
# 12, December 2013
DOI: 10.7463/1213.0646314
V.A. Tarasov, A.N. Korolev, V.D. Baskakov, V.I. Kolpakov, O.V. Zarubina
This work is a continuation of studies on an important issue of galvanic production that is providing water and recovery of valuable chemical compounds based on a design concept of a proposed operation module with a countercurrent movement of a fluid in a distributed flushing system. The article provides results of numerical calculations of the primary process and repeated jet-dynamic flushing of blind holes filled with liquid pollution by short liquid jets. In order to ensure an effective removal of contaminants, the method was justified for cross-feed of details relating to multi-nozzle heads.
Research of end mills during milling of body parts made of aluminum alloys
# 12, December 2013
DOI: 10.7463/1213.0634375
S.V. Grubyy, A.M. Zaicev
Conditions of milling cut of work pieces made of aluminum alloys by end mills were considered in this article. The authors analysed parameters of the cross-section cutting layer, shear angle, contact pressure on working surfaces of the tooth’s cutting edge. A technique for calculating power, torque and contact pressure from a tool’s cutting edge on the processed surface during milling cut by end mills was developed. The method was designed for taking into account the restrictions on power parameters of the milling process when selecting operational parameters. In the experimental part of this work cutting properties of interlocking and solid hard-alloy end mills were investigated during milling of grooves, pockets, ledges in work pieces made of aluminium alloys.
Estimation of the stress-strain state of work pieces affected by cavitational-abrasive wear
# 12, December 2013
DOI: 10.7463/1213.0623531
L.A. Tischenko, A.A. Kovalev, V.D. Shashurin
This article presents the results of quantitative assessment of process parameters which occur in materials of work pieces susceptible to cavitational-abrasive wear when in operation in aggressive fluid media. The authors propose a new algorithm for estimating the stress-strain state of materials of technical system’s elements affected by abrasive particles and micro water jets resulting from collapse of cavity pockets. Several hypotheses were introduced for describing this physical phenomenon; they were justified in this work. On the basis of the proposed algorithm evaluation calculations of existent parameters which allow one to make conclusions on the stress-strain state of several materials were performed. The obtained results were presented in the form of functional dependences.

Constructional Material Processing in Machine Building

Anticorrosive processing of low-carbonaceous steel by pulsed plasma flows
# 12, December 2013
DOI: 10.7463/1213.0670510
A.S. Kamrukov, E.I. Denisov, N.P. Kozlov, E.A. Lushnikov
Development of new progressive technologies for improving corrosion resistance of construction materials is a crucial scientific and technical task which could be solved efficiently by modification of various plasma methods. This work considers a possibility of obtaining the corrosion-resisting effect by modifying physical and chemical properties of constructive materials’ surfaces during processing with high enthalpy pulsed plasma flows. A pulsed technological plasma burner based on a high-current discharge magnetoplasma compressor in the atmosphere was developed. Results of an experimental research of energetic, thermodynamic and temporal characteristics of the impact of pulsed plasma flows on construction materials were presented: the temperature of the plasma flow was 13000 …15000K, of the plasma pressure – 70…390 bar, radiation flux density was up to 300 kW/cm2, energy density of the plasma exposure was 10... 40 J/cm2, a typical exposure time was 65 ... 125 ms. Irradiation experiments with pulsed plasma flows made of samples of St3 steel were performed. Evaluation of corrosion properties of plasma-modified surfaces was carried out. A significant increase in corrosion resistance of surfaces of structural carbon steels modified by such kind of treatment was demonstrated using the method of accelerated tests.
Selection of a metal-cutting machine model: a formalized approach
# 12, December 2013
DOI: 10.7463/1213.0640867
G.P. Lazarenro
The article covers formalisation of procedures of selecting technical equipment tools during the design of technological processes. A general analysis of the problem was carried out; it was approbated on a practical task of machine selection. The problem was solved by a standard two-stage scheme: 1 – selection of potentially suitable models of machine; 2 - selection of the most preferred model. The methodology of comparative analysis of numerical and linguistic vectors was applied as a tool for formalising the solving procedure of this task along with the methodology of multi-criteria optimisation of choice. The obtained results confirmed the possibility of practical solving of this problem based on application of the mechanisms of the quantitative analysis and the procedures described by formal algorithms.

Power Machine Building, Metallurgical Machine Building and Chemical Engineering

Investigation of optical disruptive discharges in complex gaseous mixtures
# 12, December 2013
DOI: 10.7463/1213.0669474
E.Yu. Loktionov, N.A. Pasechnikov, Yu.S. Protasov, Yu.Yu. Protasov
Optical, electrical and combined electro-optical thresholds of disruptive discharges for noble gases, their binary and triple mixtures of different compositions were experimentally evaluated. The possibility of mutual reduction in discharge thresholds at a simultaneous optical and electrical impact on gas was studied along with the possibility of reduction in thresholds of a combined discharge when basic gas has additions of another gas are made. It was shown that reduction in the threshold of an optical discharge in the presence of an electric field was quite significant at low pressures. For the first time mutual suppression (negative interference) of gaseous dopants’ effect on changes in discharges’ thresholds (both optical and electro-optical) in case of triple gas mixtures was demonstrated.
Optimization of an electrohydraulic actuator for a servo drive with throttle control
# 12, December 2013
DOI: 10.7463/1213.0637872
D.S. Zamaraev, D.N. Popov
The paper presents a problem-solving procedure for selecting parameters of an electrohydraulic actuator in order to reduce response time and hydraulic power consumption. To perform such optimization design variables of an electrohydraulic servo drive were selected; objectives were proposed to estimate design alternatives. An example of two-criterion optimization of a servo drive with throttle control was presented. These criteria were control flow and response time. Multi-objective modification of a genetic algorithm was used to obtain a Pareto front approximation. The concept described in this paper is based on generalization of optimization methods for the electrohydraulic servo actuator known from literature references and includes new proposals on the algorithm structure

Transportation, Mining and Construction Machine Building

Bench test results of a sixteen-step gearbox with automatic control
# 12, December 2013
DOI: 10.7463/1213.0671097
A.N. Blokhin, A.P. Nedyalkov, A.E. Kropp
The paper presents theoretical dependences which allow to calculate the main parameters of a pneumatic actuator of a multi-step mechanical synchronized gearbox, depending on the parameters of an engine, a gearbox and conditions of traveling resistance during the synchronization process with alternating pressure and various air escapes into a pneumatic cylinder: critical and subcritical escapes at constant pressure. Results of theoretical investigations and bench tests were compared. Calculated values of synchronization time at separate stages and at the whole cycle of gear actuation differed from experimental data no more than by 10-25%.
Development of general principles for optimal control of caterpillar machine movement
# 12, December 2013
DOI: 10.7463/1213.0671078
M.V. Vyaznikov
The article deals with a problem of optimal control of caterpillar machine movement with regard to the driver as a feedback loop of the dynamic system. In order to build a control algorithm a mathematical model of caterpillar machine motion which takes into account non-holonomic links between caterpillars and soil was used. External control action was formalised in the form of an objective function. State parameters of an object were determined by the measuring system which was also subject to random perturbations. The maximum principle of P.S. Pontryagin was used for synthesising optimal control of a caterpillar machine. During optimization of an object one wants to find a vector of control action considering constraints from the minimum of composed functions expressing specified criteria. A problem of synthesizing time optimal control was considered. It was noticed that a system is time optimal if minimal transition time is provided, considering restrictions imposed on control and output coordinates. The principle of forcing dynamic processes at certain time intervals by increasing control signal within the specified range was used to reduce duration of the transition process.

Mathematics and Mathematical Modeling

A dynamic model of a cell population system
# 12, December 2013
DOI: 10.7463/1213.0646463
M.S. Vinogradova
This paper deals with development of a mathematical model of population dynamics of human stem cells being cultured in vitro. This investigation was inspired by intensive development of stem cell transplantation. The authors investigated formation processes of a cell population with chromosome abnormalities in a population of normal cells along with co-development of these populations in vitro. In this paper a refined continuous dynamic model of an isolated population system consisting of a population of normal stem cells and a population of cells with chromosomal abnormalities was proposed. An essential feature of this model is a necessity for biological characteristics of processes that occur in a cell population system for its creation. These characteristics are:  a portion of cells divided within a specified time, a portion of dead cells and a portion of cells passed into a population of abnormal cells from normal cell populations. This approach allows to provide a more detailed analysis of the impact of different "primary" parameters on dynamics of a population system. Parametric analysis of the model was carried out; the main scenarios of its development were described. The proposed model allows to simulate correctly the main evolution scenarios of a population system which are known from experimental investigations.
Hybrid algorithms for optimization of hydro-mechanical systems with derivative-free local search
# 12, December 2013
DOI: 10.7463/1213.0604100
V.D. Sulimov, P.M. Shkapov
This article deals with problems of global optimization and computational diagnostics of hydro-mechanical systems. It was assumed that criterion functions were continuous, Lipschitzian, multiextremal and incompletely differentiable. Novel hybrid algorithms were proposed; these algorithms use the modern stochastic Particle Collision Algorithm based on an analogy with absorption and scattering processes for nuclear particles, for scanning a search space. Local search was implemented with the use of two derivative-free methods: a space filling curve method and a convergent variant of the Nelder-Mead simplex method. Results of solving the model problem in identification of the coolant phase constitution anomalies in the reactor circuit were presented.

Aeronautical and Rocket Space Engineering

Investigation of combined action of a circuit - "thermo-emission reactor – plasma current convertor – spacecraft propulsion system’s load"
# 12, December 2013
DOI: 10.7463/1213.0669487
E.V. Onufrieva, V.V. Onufriev, V.V. Sinyavskii, A.B. Ivashkin
The article presents a description of operation of an electrical nonlinear circuit model including a source (thermo-emission reactor), a plasma current converter (thermo-emission diode) and a resistive load. Amplitude-frequency responses (AFR), phase-frequency characteristics (PFC), phase curves and load current waveforms against the parameters of the thermo-emission diode were studied along with operation stability of the following circuit: thermo-emission reactor – thermo-emission diode - resistive load. The operation of this electrical nonlinear circuit was simulated by using MATLAB - SIMULINK software package; this allowed to obtain accurate solutions for AFR and PFC. Results of circuit operation dynamics were obtained for different current waveforms (sine-wave and meander-wave). Areas of possible unstable operation of the spacecraft propulsion system which depends on reactive resistances of the thermo emission reactor and the plasma current converter were presented.
Air breathing Hall Effect thrusters for Low Earth Orbit spacecraft
# 12, December 2013
DOI: 10.7463/1213.0660910
D.V. Duhopel'nikov, S.G. Ivakhnenko, D.A. Kurilovich
The authors consider a possibility of using a Hall Effect thruster working with an ambient atmospheric gas for orbital station-keeping. Relation between thrust and atmospheric drag force was obtained. It was shown that there is a critical value of accelerating voltage which provides equality of thrust and air drag force. Relation between this critical accelerating voltage and spacecraft velocity, as well as relation between thrust efficiency and the ratio of air intake area to the spacecraft's area, were obtained. Basic ways of improving efficiency of the air breathing Hall Effect thruster were proposed.
Analysis and modeling of worst-case situations during uncontrolled deployment of space cable system
# 12, December 2013
DOI: 10.7463/1213.0633253
A.V. Popov
Different variants of worst-case situations involving space cable systems of small length during uncontrolled deployment were considered in this paper. As a rule, these situations are caused by an abrupt change in the tensile force of the cable. This leads, depending on the flick, to a springing of the end-bodies and their return motion with the risk of collision, or to a break of the cable system, followed by independent movement of the end-bodies. In addition, worst-case situations may be caused by collisions of the cable with micrometeorites or debris objects that are likely to lead to a sudden breakage. In examples, development of the discussed situations was analyzed; absence of collisions in cases of dangerous approaching of end-bodies was demonstrated. It was proposed to introduce design features for increasing safety of uncontrolled deployment in potentially dangerous situations. Analytical and numerical methods were used for solving the motion problem after separation. Analytical solution of simultaneous motion of two bodies in orbit was used for extracting information about the distance between bodies during their motion. Numerical solution uses a model of the cable system in the form of a chain of weighty material points connected by viscoelastic links. In this model there are solid end-bodies; presence of end friction dampers is also simulated; influence of the Earth non-sphericity and atmospheric drag was taken into account. With the use of numerical solutions a set of trajectories was obtained; cases of dangerous approaching of end-bodies were demonstrated. For such situations it was suggested that cable sections with regulated break force should be used. Forms and motion trajectories of developed cable systems were presented. Methods used in this paper can be applied to planning and justifying safety of spacecraft flights with uncontrolled deployment of the space cable system.
On motion of a solid body with a cryogenic liquid
# 12, December 2013
DOI: 10.7463/1213.0627898
Min Vin Ai, A.N. Temnov
Relevance of this work is associated with the problem caused by ever-increasing usage of cryogenic fluids in the space rocket technology. Further exploration of space is impossible without creation of orbital cryogenic gas stations. A distinctive feature of all cryogenic liquids is a non-uniform distribution of density and temperature observed during all modes of operation and storage. A suitable model for studying motion of a mechanical system is a heterogeneous incompressible fluid. In this work interaction between a heterogeneous incompressible fluid and a movable rigid body’s cavity was discussed. Cases in which motion of a rigid body is caused by the action of momentary forces or cases of abrupt movement were considered. The authors proposed a concept of quasi-potential of fluid velocities was introduced; solution to the problem of motion of a rigid body with a cylindrical cavity partially or completely filled with a cryogenic liquid.

Instrument Engineering, Metrology and Information-Measuring Devices and Systems

Influence of frequency on the magnetic field vector’s magnitude of a coil of arbitrary shape in free space
# 12, December 2013
DOI: 10.7463/1213.0676328
E.V. Arbuzov, E.O. Petrenko
This article considers a possibility of using a mathematical apparatus of direct-current fields for modeling distribution of the magnetic field vector during calculation of quasi-static fields of eddy current conversion units produced by an alternating current. Equivalence of field patterns was proved; it was also shown that there is no influence of the frequency of an alternating current which powers the eddy current conversion unit on the filed pattern for attachable parametric transducers of an arbitrary shape in free space. Theoretical justification was given for various frequencies along with experimental verification.
Full scale tests of an IR Fourier spectral-radiometer for remote atmospheric sounding
# 12, December 2013
DOI: 10.7463/1213.0669654
P.S. Konstantinov, V.I. Alehnovich, N.N. Kulakova, G.V. Podguzov
This article describes full-scale tests of a prototype of a IR Fourier spectral-radiometer for remote atmospheric sounding. The article presents an experimental procedure, which would allow one to determine the efficiency of the device and its metrological characteristics. Additionally, the article presents results of tests with the use of test objects such as films made of different polymer compounds (polyester, Teflon, polyethylene, polystyrene) with known thickness, as well as vapor of ammonia (NH3) and sulfur hexafluoride (SF6) in gaseous phase. The spectra of test objects were registered against various background objects - a clear sky, a cloudy sky, a model of a black body with a known temperature.
Use of an infrared diaphanoscopy method for estimating the condition of mouth cavity’s soft tissues in dentistry
# 12, December 2013
DOI: 10.7463/1213.0669704
A.V. Kolpakov, A.L. Makarov, I.N. Spiridonov
This article presents a possibility of applying optical methods - for instance, a method of infrared diaphanoscopy, to detect inflammation in tissues of a mouth cavity at the stage of primary damage. The authors investigated the main exogenous and endogenous factors of inflammatory diseases of mouth cavity tissues, the mechanism of their emergence and expansion; the behavior of tissues’ optical and physical properties in the mouth cavity at various stages of inflammation was demonstrated; interrelation of those properties with the change in chromophore concentration with the expansion of the inflammatory process was also revealed.
Algorithm for determination of location of ground objects under conditions of input data of low accuracy
# 12, December 2013
DOI: 10.7463/1213.0659353
V.N. Jurakovsky, K.S. Kondrashov
In this paper the authors consider an algorithm for determination of ground objects’ location in the space-based passive radar system under conditions of the input data of low accuracy. Use of a passive radar allows to determine the location of ground objects, in particular, active radiolocation stations by its radiation under conditions of low energy consumption on board of a spacecraft. In this regard, bearing accuracy is quite low at the output of a signal processor. Lack of computing resources, which is typical for embedded systems, must be also taken into account. These features make it difficult to synthesize an effective location algorithm carrying out secondary radar data processing. In this paper theoretical theses of the location algorithm and particularities of its implementation within a space-based embedded computer are presented. In particular, it is subject to bearing accuracy achievable in the algorithm and processing of vast surveillance zone which is challenging due to lack of computing resources.
Automated complex for determination of the hormonal status of breast cancer using a method of immunocytochemistry
# 12, December 2013
DOI: 10.7463/1213.0628098
A.V. Samorodov, O.A. Artyukhova, D.A. Dobrolubova, N.S. Klimenko, E.Yu. Amel'kina, N.A. Voinova, E.N. Slavnova
The paper presents results of developing an automated complex for determination of the hormonal status of breast cancer using an immunocytochemistry method. The complex performs automated scanning of medication and image capturing by means of an automated computer-driven microscope, as well as automated image analysis which results in estimation of Allred’s scores; the developed complex is capable of visual verification and correction of analysis results if it is necessary. Experimental studies demonstrated high repeatable accuracy of automated analysis results and agreement of automatically drawn conclusions on the hormonal status of breast cancer with the ones obtained by cytologist during visual microscopic examination.

Informatics, Computer Science and Management

Promising structures with memory based on inorganic materials
# 12, December 2013
DOI: 10.7463/1213.0669629
Yu.V. Hrapovickaya, N.E. Maslova, M.L. Zanaveskin
At present time many research groups working in the field of microelectronics are trying to develop a technology for producing a memristor also investigating possibilities of its integration into the CMOS process. Main classes of materials with memory effect such as metallic oxides, chalcogenides, solid electrolytes, polymers etc. were found. All of these classes have resistive switching properties; but their switching mechanisms are different. There are not fully studied elements in literature, but for some of them a stable memristive effect was achieved. Also an operating model for these elements was developed. In this article the authors present a review of such structures with a memory effect based on inorganic materials and analysis of their characteristics along with possible application domains.
GPU realization of a neural network face recognition algorithm
# 12, December 2013
DOI: 10.7463/1213.0659387
V.I. Terehov
In this paper the author considers implementation of a neural network face recognition algorithm on a graphical processing unit. The algorithm is based on a classic multilayer perceptron. The training method is backward propagation of errors. This implementation has a seven times performance boost compared with traditional CPU implementation. Error rate of recognition approximately equals to 1%.
Method of automated construction of a digital relief model
# 12, December 2013
DOI: 10.7463/1213.0657404
E.I. Afinogenov
The author considers a problem of effective construction of a digital relief model (DRM) for a certain region on the basis of a large number of aerial photographs. Main stages of DRM construction were described. Special attention was paid to increase efficiency of search for the “nearest” (in terms of content) images in the database; it was proposed to use a search scheme based on inverse indexing of images’ unique characteristics and the database organized in the form of a tree of “visual words”. Construction of a lexical tree with the use of hierarchical clusterization of the attribute space, obtained on the basis of SIFT- descriptors, was shown; weighing coefficients of “visual words”, calculated on the principle of TF-IDF (Term Frequency – Inverse Document Frequency), were taken into account.
Abstractions and base operations of a specialized description language of algorithms for solving problems of structural analysis and synthesis
# 12, December 2013
DOI: 10.7463/1213.0656686
G.S. Ivanova
This article justifies the need for a specialized programming language that would allow to describe solving procedures for tasks of structural analysis and synthesis in terms of mathematical models being used. Compared with the existing languages and subroutine libraries such language would not only allow to reduce program development time significantly but also provide an opportunity to develop more efficient programs in terms of computational complexity of algorithms and runtime. According to the analysis of algorithms and representations of graph models a set of the necessary abstractions and operations on them was determined. The abstractions such as "set", "multi-set", "sequence", "vector" and "matrix" were proposed for basic abstractions. Operations on these abstractions were divided into mathematical and related to specific implementation features of the algorithm descriptions. A set of elementary operations of the indicated types was defined for each abstraction.
Synthesis of a quasi-optimal trajectory of an unmanned aerial vehicle
# 12, December 2013
DOI: 10.7463/1213.0646471
M.A. Velischanskii
A problem of constructing spatial trajectories for unmanned aerial vehicles (UAV) and synthesis of program controls were considered in this paper. A nonlinear mathematical model of UAV movement as a material point along the trajectory was described. A kinematic trajectory is based on the time-dependent polynomials. Program control implementing this trajectory is based on the concept of inverse dynamic problems. Кинематическая траектория строится на основе полиномов по времени, а реализующее ее программное управление – на основе концепции обратных задач динамики. The purpose of this paper is to determine the minimal time of the UAV maneuver so that the constructed kinematic trajectory and control would satisfy the limits on state variables and control. Numerical optimization methods were used to solve this problem. Results of numerical simulation were also presented.
Two-criterion identification of kinetic parameters of olefin hydroalumination by HAlBui2 and ClAlBui2
# 12, December 2013
DOI: 10.7463/1213.0645511
I.M. Gubaidullin, A.P. Karpenko, L.F. Nurislamova, A.S. Savelov
This work was carried out in the context of investigation and development of original two-component neutral catalyst systems made of mixed-valence metal compounds (titanium and zirconium) and organoaluminum compounds. A problem of identification of kinetic parameters of olefin hydroalumination, which belongs to a class of inverse problems of chemical kinetics, was considered in this paper. As a rule, identification problem is formulated as a single-criterion optimization problem for residuals between calculations and experimental data. The disadvantage of such a formulation consists in the fact that important prior information about kinetic features of a chemical reaction under investigation is ignored during identification. A distinct feature and novelty of this work is a new formulation of the identification problem; the problem was considered as a two-criterion optimization task which allowed to take into account both experimental data on the kinetics of the chemical reaction under investigation and prior information about this reaction. Solution to this problem represents the Pareto set. In order to approximate the Pareto set a modified Adaptive Weighted Sum method was used. One of the purposes of this work is to test the modified AWS method while solving real world two-criterion inverse problems of chemical kinetics. Two-criterion identification problem of kinetics of olefin hydroalumination by halbui2 and clalbui2 was formulated in this work. The algorithms and software which were used are described in this paper. The obtained calculation results were analyzed and discussed. 
Solving the inverse dynamic problem with the use of simulation systems
# 12, December 2013
DOI: 10.7463/1213.0637676
V.G. Fedoruk, V.A. Trudonoshin, E.V. Fedoruk, V. A. Martynyuk
This paper describes a method for solving the inverse dynamic problem with the use of the systems for simulation of complex technical objects. Mathematical basis for solving that problem were presented. The problem-solving procedure contains two stages. Numerical simulation of a mechanical system under given external influence is performed at the first stage; this influence is represented as dependence of position coordinates of the system’s several elements on time. During this simulation reciprocal deflections of the operating mechanism’s application points are recorded. At the second stage previously applied forces are removed. Simulation of the system under the influence of displacements in the operating mechanisms determined at the first stage is carried out. In the process created forces are registered. An example of solving the inverse dynamic problem for a tripod was presented.

Mechanics

Numerical simulation of shock-wave deformation of flexible armored composite materials
# 12, December 2013
DOI: 10.7463/1213.0665297
Yu.I. Dimitrienko, Yu.V. Belenovskaya, V.A. Aniskovich
A mathematical model of deformation of flexible armored materials based on aramid fabric under high-speed effects was proposed. The model takes into account the following peculiarities of deformation parameters of composite materials of the specified class: possibility of deformation without destruction at finite deformations, a considerable difference between stress-deformation diagrams under tension and under compression, dependence of these diagrams on a loading rate, pseudo-plastic features of materials caused by pulling out threads from fabric and/or a plastic character of deformation, anisotropy of nonlinear-elastic and visco-plastic properties and other effects. A problem statement was formulated for dynamic deformation of flexible armored materials. In order to solve the problem in a two-dimensional case the method of band-adaptive grids was applied. An example of numerical solution of the problem was presented for a high-speed action of a striker onto a flexible armored material; some effects of deformation of materials of the specified class were analyzed.
Comparative analysis of methods of getting inconsistent mass matrices
# 12, December 2013
DOI: 10.7463/1213.0624689
O.D. Baceva, S.N. Dmitriev
Several various methods could be applied for description of mass-inertia properties of the finite element; each method leads to a different mass matrix. In particular, one could use the method of lumped masses, various shape functions both matching with (consistent) or distinct from shape functions for a stiffness matrix. Other approaches are also possible. The purpose of this work was to analyze some non-trivial approaches to determination of a mass matrix, such as non-standard shape functions, oscillation modes of a bar element, a method of combining different mass matrices with weighting factors. The article compares five different mass matrices by the example of a bar finite element and identifies inherent errors of these matrices obtained during determination of eigenfrequencies of the fixed bar. A system of equations for the finite element method for all mass matrices was solved analytically in the trigonometric series defined at the nodal points. It was shown that calculation of eigenfrequency based on inconsistent mass matrices could provide higher accuracy in comparison with diagonal and consistent matrices.

Equipment and methods of experimental physics

Influence of methane on delay of hydrogen ignition during pulsed discharge escape to the air from a high-pressure chamber
# 12, December 2013
DOI: 10.7463/1213.0633287
A.Yu. Mikushkin, S.V. Golovastov, V.M. Bocharnikov
Influence of methane on diffusion auto-ignition of hydrogen during pulsed discharge escape to the air from a high-pressure chamber was experimentally determined. Pulsed discharge occurred from a high-pressure chamber due to a breakup of the diaphragm. Hydrogen was mixed with air at the contact border. In this case hydrogen ignition point was achieved by means of air heating with a created shock wave which occurred as a result of non-stationary hydrogen discharge from a high-pressure chamber. It was shown that increase in the amount of methane led to increase in the delay of ignition. It was proposed that there is a kinetic mechanism of inhibition of burning in addition to a thermal process. The obtained results could be used for preventing hydrogen ignition in storage and while operating in high-pressure systems.

Optics

Promising methods for quality control test of large convex aspherical mirrors
# 12, December 2013
DOI: 10.7463/1213.0645432
V.I Batshev, E.A. Badunova, O.V. Pol'schikova
Promising methods for quality control test of large convex aspherical mirrors were considered in this article. These methods are based on a new scheme of illuminating the mirror under control by a parallel multiple-beam where the beams are perpendicular to the mirror’s symmetry axis. The main advantage of such methods is that they don't require auxiliary large-size optical elements. A new non-interferometric method for a quality control test of convex aspherical mirrors with high aperture (angle between the optical axis and the marginal normal to the mirror is more than 45 degrees) was developed on the basis of the specified illuminating scheme.

Power Engineering

Investigation of interaction of deuterium plasma with tungsten targets
# 12, December 2013
DOI: 10.7463/1213.0669439
A.M. Zimin, V.M Sharapov, S.E. Krivickii, V.S. Kulikauskas
Assessment of retention of hydrogen isotopes in co-deposited films is of great interest for the problem of selecting materials for plasma-facing components of International Thermonuclear Experimental Reactor. The purpose of this work was to study deposition peculiarities of tungsten-deuterium films formed on silicon substrates by sputtering tungsten targets in deuterium plasma of magnetron discharge. Deuterium content in films was determined by the Elastic Recoil Detection method; tungsten concentration was calculated from the measurements of the film’s weight; the film’s thickness was determined by a profilometer. It was established that deuterium content in co-deposited films is comparable with that of tungsten atoms. It was suggested that the retained deuterium is located in the pores formed during the film growth. Increase in the distance between the target and substrate leads to decrease in the deuterium content in the film and subsequently to reduction in film porosity and to growth of its density.
Ensuring safety in factory shops under conditions of technological emissions of uranium hexafluoride
# 12, December 2013
DOI: 10.7463/1213.0625484
S.P. Babenko, A.V. Bad'in
This paper presents a review of literature and original methods for solving tasks of ensuring safety in factory shops at factories of nuclear industry that use uranium hexafluoride. The authors consider theoretical models of air pollution in factory shops with gaseous uranium hexafluoride and its hydrolysis products, settling of these products on factory surfaces, inhalation and percutaneous penetration of these products into human body. Capabilities of these models and some results of the calculations were described. This article was intended for publication in the journal "Science and Education: Electronic Scientific and Technical Periodical”.

Education Sciences

Special characteristics of training partially deaf students
# 12, December 2013
DOI: 10.7463/1213.0658241
N.A. Yaroslavceva
This article presents printed and electronic teaching aids used for training partially deaf students in a machining laboratory; these educational guides combine theoretical knowledge, materials that help to develop certain skills and various forms of tests and self-assessment. A common approach to development of such training aids and their methodical features were presented. A fragment of such a teaching guide meant for out-of-school self-guided work of partially deaf students was also presented in this paper for illustrative purposes. This teaching guide would help to master missed materials without an instructor.
 
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