Другие журналы

scientific edition of Bauman MSTU

SCIENCE & EDUCATION

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

# 06, June 2012

Machine Building and Engineering Science

Issues of damping and absorbing properties of materials and structures
# 06, June 2012
DOI: 10.7463/0612.0442023
V.A. Markov, V.A. Pusev, V.V. Selivanov
As a rule, damping and absorbing properties of materials and structures are determined, basing on the German-French version of terminology. Absorbing properties of porous materials and honeycomb structures can be quantified by energy density shock absorption and energy efficient impact absorption based on the diagram of deformation of porous materials and honeycomb structures. These estimates of single (one-time) shock absorbers are similar to the impact energy received by the absorber, and to efficient energy shock absorption used in the evaluation of multiple shock absorbers. However, in the automobile industry damper is called shock absorber (using the Latin version of the word "depreciation"), and in the field of explosive and impact loading of structures shock absorber is called damper. Taking into account this fact will allow to avoid confusion in the domestic scientific and technical literature.
Comparison of service characteristics of coatings made of austenitic and martensitic stainless steels by means of laser gas-powder cladding.
# 06, June 2012
DOI: 10.7463/0612.0418550
A.G. Grigor'yanc, A.I. Misyurov, R.S. Tret'yakov, A.Ya. Stavertii
In this article the authors consider properties of Cr17Ni13Mo2Ti and 40Cr13 coatings made by coaxial gas-powder laser cladding. CW fiber laser emission was used to create such coatings. Operating characteristics of coatings made by laser cladding of these steels are currently byways of learning. Usage of powder as a filler material is economically advantageous because it allows to produce coatings with different chemical compositions and properties. Besides, in comparison with the wire filler, uniform mapping of powder alloys onto difficult trajectories is easier. The article covers investigation of coating structure and mechanical properties along with establishment of their applicability domains in order to meet the demands of modern machine building.
Energy characteristic of material cutability
# 06, June 2012
DOI: 10.7463/0612.0369499
V.M. Yaroslavtsev
 Dependence of material cutability on specific work of inelastic deformation until destruction was obtained experimentally. It was shown that technological and technical economical characteristics of cutting were energetic characteristics. Application of energetic characteristic of cutability was demonstrated by the example of efficiency estimation of the combined machining method – that is, cutting with outrunning inelastic deformation (OID) for which known cutability criteria are unacceptable.

Constructional Material Processing in Machine Building

Modeling of dependences of physical-mechanical properties on parameters of micro- and nanostructure polymer composite materials
# 06, June 2012
DOI: 10.7463/0612.0431339
S.A. Lur'e, Yu.M. Mironov, V.A. Nelyub, A.S. Borodulin, I.V. Chudnov, I.A. Buyanov, Yu.O. Solyaev
The authors propose a mathematical model of polymer composite armored with fillers of various sizes. It is shown that the obtained theoretical relations allow to predict physical-mechanical properties of certain material reliably and to determine an optimal variant of filling with micro- and nano-inclusions.
Research of cutting properties of boron nitride cutters
# 06, June 2012
DOI: 10.7463/0612.0423622
S.V. Grubyy, V.V. Lapshin
The authors analyze properties of ultra-hard tool materials on the basis of boron nitride of various brands and manufacturers – both domestic and foreign. Recommendations on regime parameters of processing work pieces made of hardened steel were analyzed. Calculation dependences of tool life, cutting speed, forces and roughness of the processed surface are given. The authors present the results of their experimental research of cutting properties of various brands of tool materials on the basis of boron nitride when processing work pieces made of hardened steel. Directions for further investigations of tools made of modern materials on the basis of boron nitride were outlined.

Transportation, Mining and Construction Machine Building

Evaluating the effectiveness of control laws for individual drive wheeled propulsion systems
# 06, June 2012
DOI: 10.7463/0612.0403852
V.A. Gorelov, L.A. Maslennikov, A.V. Miroshnichenko
The authors present the results of theoretical studies of motion of a wheel transport system with individual power distribution to the wheels with the developed control laws for electromechanical transmission, basing on the principle of redistribution of moments proportional to the relative normal load to be carried by each propeller. The authors studied two versions of the law controlling traction electric motors: "torque" and "the degree of the total power." Advantages of the "degree of use of the total power" approach are proved by the results of mathematical simulation of transport complex movement with the  8 × 8 wheel forumla on the rigid support base for the following cases: ascent, curvilinear motion with a fixed radius, rectilinear acceleration with different intensity effects on the controls (accelerator pedal).

Aeronautical and Rocket Space Engineering

New approach to cooling of rocket oxygen-kerosene engine
# 06, June 2012
DOI: 10.7463/0612.0431608
F.V. Pelevin, N.I. Avraamov, P.Yu. Semenov
 The authors analyzed modernization of oxygen-kerosene engines. It was shown that the traditional ribbed cooling channel couldn’t increase efficiency of the first stage oxygen-kerosene engines. New methods of LPE cooling are considered.

Instrument Engineering, Metrology and Information-Measuring Devices and Systems

Errors of rotary vibratory gyroscope with rotating circular oscillations carrier
# 06, June 2012
DOI: 10.7463/0612.0440772
A.V. Kuleshov, V.V. Fateev
In the article the authors consider a rotary vibratory gyroscope for the rotating unit with negative velocity feedback and with the integrator in the output stage of the electronic module. The authors present kinematic and structural gyroscope schemes. They show features of behavior of the gyroscope with a circular oscillations carrier. There are also results of their research of the impact of the circular oscillation frequency carrier on the amplitude and phase of the output device.
Processing interferograms from static Fourier transform spectrometer
# 06, June 2012
DOI: 10.7463/0612.0432616
I.S. Golyak, A.A. Esakov
The authors propose an algorithm for processing interferograms obtained with a static Fourier spectrometer. The spectra of secondary radiation of a certain range of substances in the visible and near ultraviolet fields of the spectrum appear when they are excited by different sources of radiation. The authors present and discuss the results of processing of their experiments.
Mathematical model of digital infrared remote sensing system
# 06, June 2012
DOI: 10.7463/0612.0423297
Yu.G. Veselov, S.P. Gulevitch, I.V. Karpikov, A.S. Ostrovsky
 A mathematical model of the digital infrared remote sensing system (IRS) of "watching" type was developed. It allows to estimate the value of IRS angular resolution depending on application conditions and its structural and technological features.
Laser photo-acoustic analysis of multicomponent gas mixtures
# 06, June 2012
DOI: 10.7463/0612.0368798
M.L. Belov, A.Yu. Busargin, V.A. Gorodnichev, L.N. Eremenko
The authors describe the problem of recovery of gas concentration in laser photo-acoustic analysis. Signal processing procedures based on projective method are described for the differential absorption method. Usage of the projective method was proved to be efficient for solving the problem of recovery of gas concentration for multi-component gas mixtures.

Radio Engineering and Communication

Structural and parametric synthesis of PLL frequency synthesizer
# 06, June 2012
DOI: 10.7463/0612.0423339
L.N. Kazakov, D.Yu. Vishnyakov
In this paper structural and parametric synthesis of PLL frequency synthesizers is proposed. The peculiarity of these devices includes existence of both external and internal noise in the system, which, in this case, does not allow to apply the classical method of structural synthesis based on the theory of optimal linear and nonlinear filtering. To solve the problem two steps were proposed. At the first stage optimal filters are synthesized separately for external and internal signal and noise sources. At the second stage structural synthesis is used, which includes properties of optimal filters obtained at the first stage.

Informatics, Computer Science and Management

Determination of car brand on the video frame using the Viola-Jones modified algorithm
# 06, June 2012
DOI: 10.7463/0612.0434600
I.E. Kopylov, K.L. Tassov
This article describes an approach to defining the brand of a vehicle by images received from systems of recognition of state license plates of vehicles. Brand logo is used as a criterion for identification. To solve the problem the authors developed a methodology based on the Viola-Jones algorithm for detecting objects. The authors studied determining the correctness of its work for various brands of vehicles. When using this method the accuracy of brand vehicle recognition averaged to 85%, which will allow to apply the developed method in practice.
Adaptive weighted sum method for solving Pareto-approximation problem
# 06, June 2012
DOI: 10.7463/0612.0423283
A.P. Karpenko, A.S. Savelov, A.S. Semenikhin
The authors consider solving the discrete problem of Pareto set and frontier optimization in the multi-criterion optimization problem. The aim of this work was to examine the efficiency of Adaptive Weighted Sum method (AWS) which was initially developed by J-H. Ryu, S. Kim and H. Wan. Comparing to the original research, the authors used a wider range of multi-criterion benchmark optimization problems. A range of limitations of AWS methodology and usage complexity was found. Modification of the method was proposed to resolve the problems and limitations.
Encoding of the binary sequence with the use of discrete chaotic maps
# 06, June 2012
DOI: 10.7463/0612.0402537
S.V. Mitin
This article presents a method of encoding of the binary sequences with the use of discrete chaotic maps. It was shown that in real systems the method of truncation to encode a message by blocks of bits should be used. The synthesis of a chaotic map with the specified probability density function was carried out. Maps and functions’ graphs, which are using for encoding of the binary sequence, are also included in the article.
The Laplace–Stieltjes transform of connection time of two tables in parallel database
# 06, June 2012
DOI: 10.7463/0612.0390320
V.L. Pluzhnikov, A.S. Domnikov
Connection of two tables in parallel database system (PDBS) was analyzed in this article. The Laplace–Stieltjes transform (LST) of connection time of two tables with NLJ and HJ methods in PDBS was introduced. Random character of the number of rows in the connecting tables is considered along with node fragmentation of tables, filtration of all table entries, probability of matching of connection attribute values, variants of hash-table location in the memory and parameters of interprocessor communication of PDBS nodes. Generating function of resultant value of entries, obtained after connection of tables in any node is presented in the article.
Method of hierarchical study of complex discrete structures
# 06, June 2012
DOI: 10.7463/0612.0370230
I.V. Rudakov
 The proposed approach to the study of complex hierarchical structures allows to carry out discrete analysis of a complex structure functioning with the use of macro-modeling methods and subsequent automatic decomposition. Practical implementation of hierarchical investigation of complex discrete structures is based on technology of object-oriented programming. A language oriented to transacts was developed as a tool of analysis and verification of structure simulation. The method was tested in simulation of traffic flow in an overpass tunnel type.
Models and algorithms of multicriteria optimization of AIS with fuzzy information
# 06, June 2012
DOI: 10.7463/0612.0369542
O.I. Lisov, A.B. Markov
The paper describes the formalization process of optimization of automated information system’s quality based on fuzzy logic, information system model as an object of optimization in terms of population genetic, genetic algorithm with fuzzy model for optimization, and also methods of conversion of the population with usage of heuristic algorithms.

Mechanics

Integration possibilities of the chain theory methods and the automatic control theory in solving tasks of dynamics of machines
# 06, June 2012
DOI: 10.7463/0612.0378699
S.V. Eliseev, A.O. Moskovskih, R.S. Bolshakov, A.A. Savchenko
Possibilities of creation of structural schemes of mechanical oscillation systems are considered in this article. The authors propose an integration method which combines possibilities of using principles of electromechanical analogies (mechanical chains) and rules of structure transformations with feedback coupling. A methodological base for evaluating dynamic properties of vibration protection systems with electromechanical couplings was proposed.

Radiophysics

Description of electromagnetic waves in a vacuum with the usage of physical quantities - polarization and magnetization
# 06, June 2012
DOI: 10.7463/0612.0425164
A.S. Chuev
Wave equations are usually differential relations between electromagnetic field quantities. However, there is a possibility of description of electromagnetic waves even in a vacuum with the use of material quantities of polarization and magnetization. A model of electromagnetic waves can be created using these physical quantities. The author’s system of physical quantities and laws was used for demonstrative description of wave and other relationships of electromagnetism.

Optics

Method of calculating a thermal lens
# 06, June 2012
DOI: 10.7463/0612.0445463
S.V. Bodrov
The author describes a method of calculation for a high-aperture two-lens thermal imager. The method includes overall calculation, taking into account the finite thickness of the lens and the calculation of third-order aberrations. The method provides the initial version of the lens which has no spherical aberration and meridional coma. The final point of the calculation is optimization of the initial system. The efficiency of the method is proved by the example of lens synthesis.
Comparison of measuring methods and modeling spectra of reflection of fiber Bragg gratings
# 06, June 2012
DOI: 10.7463/0612.0422468
S.G. Sazonkin, D.A. Dvoreckii, L.K. Denisov, A.B. Pnev, V.A. Lazarev
This work covers the study of basic characteristics and parameters of optical fiber Bragg gratings (FBG). The paper describes the main theoretical calculation methods of FBG spectral reflection and transmission coefficients and shows FBG reflection spectra measured in two different ways: by using a spectrum analyzer and a broadband pump source, and also by newly created units. The authors compared the theoretically calculated reflection spectra with the experimentally obtained by two different methods.

Electrical Engineering

Variant of constructing a regulator of excitement of synchronous electric generators which provides optimization of parameters of transient processes in conjugated power supply system
# 06, June 2012
DOI: 10.7463/0612.0415299
A.B. Borzov, A.V. Bumagin, A.V. Gondar, K.P. Likhoedenko
The authors propose an approach to construction of an adaptive system of automatic adjustment of excitement of synchronous electric generators. The authors consider optimization of transient processes characteristics in power supply systems, on the basis of indirect adaptive management with an identifier and neural network technologies. It was shown that accuracy of approximation of transient processes in a power supply system by the neural network identifier allowed to reproduce time length of the transient process to within the tenth fractions of a second.

Power Engineering

Investigation of characteristics of high-compact plate-fin heat-exchange surfaces with shifted fin
# 06, June 2012
DOI: 10.7463/0612.0431788
K.S. Egorov, N.L. Schegolev
The article presents a research problem of heat and hydraulic characteristics of high-compact plate-fin heat-exchange surfaces. These heat-exchange surfaces are widely used in aerospace applications, space and renewable power generation. The experimental facility and measurement routine are described. The experimental facility has a closed loop, which allows to use it for different working mediums (air, mixtures of inert gases etc.). A transient method of heat research was used. The experimental data for BMSTU №9 surface in the range of Reynolds numbers from 100 to 700 for air is given in the article. Obtained experimental data was compared with the data of Kays and London for surface №104.

Behaviourial Sciences

77-48211/419183 Creative groups in foreign experience
# 06, June 2012
V.V. Bushueva
The process of creative group formation at enterprises in France is presented. Creative groups have significant advantage over individual creativity. Common organization forms of creative groups were indicated. The most important factors are admission principles, stratification, duration and rhythm of creative group work, flexibility, formation process of psychological climate and so on. The role of creative group leader is important. Recommendations on using foreign creative group experience in Russia are given.

Documentary Data

77-48211/425188 Algorithms for assignment of primary keys in filled tables
# 06, June 2012
A.V. Breshenkov, Thet Tin Min
In the article the authors define a set of algorithms required for automated assignment of primary keys in filled relational tables. The problem of assigning primary keys is formulated. Informal algorithms are proposed for assignment of primary keys in filled tables.
Appendix

General Problems of Engineer Education

77-48211/419145 Application of information technologies that should improve the quality of education by the example of internet-laboratory "global navigation satellite systems"
# 06, June 2012
I.B. Vlasov, Ya.V. Mykol'nikov, D.V. Semenov, A.V. Shumov
Internet-laboratory “Global Navigation Satellites Systems” was created in the Bauman University. Laboratory allows one to carry out remote practical works for investigations of technical characteristics of navigation equipment. The hardware and software system is basic educational and methodical facility for support of remote practical works in the area of navigation systems. The application of modern educational technology improved the quality specialist training in the field of satellite navigation.
77-48211/419126 The «Smorgasbord» Approach to Educational Assessment
# 06, June 2012
A.V. Zaiceva
Classic forms of examination imply that the tasks are distributed among students randomly. In this case an advanced student may receive a problem related to the branch which he/she finds challenging, while a less diligent person will be assigned a task he/she considers easy. This paper introduces an alternative approach that gives the examinees an opportunity of choosing tasks by themselves. Although imposing certain limitations on the total number and average complexity of the tasks selected, this approach provides a wide freedom of choice and eliminates the random factor.

Foreign Education

USA: Findings Give Boost to Online Classes
# 06, June 2012
The burgeoning movement to put more college classes online, which attracted the support of Harvard University and the Massachusetts Institute of Technology earlier this month, is getting another endorsement, which may have an even greater impact: rigorous evidence that the computer can be as effective as the classroom.A new study compared two versions of an introductory statistics course, one taught face-to-face by professors and one mostly taught online with only an hour a week of 'face time'. Researchers found students fared equally well in both formats on every measure of learning. The only difference was that the online group appeared to learn faster.
NIGERIA: President Jonathan Shocked 60% of Varsity Teachers Have no Ph.D. Inaugurates Committee to Harness PGD "Best Brains".
# 06, June 2012
Nigerian President Goodluck Jonathan last week expressed shock over the revelation that more than 60% of university teachers do not have a PhD, writes Leon Usigbe for The Tribune.Speaking during the inauguration of a special committee to harness the nation’s best brains by selecting young first-class graduates to be sent for further training in the best universities around the world, he said information made available to him on Thursday by the executive secretary of the National University Commission, Professor Julius Okojie, was embarrassing.
UK: Path to University Title Smoothed as Threshold Lowered to 1,000 Students
# 06, June 2012
The UK government is set to push ahead with plans to create a new generation of universities by lowering the qualifying threshold for 'university' title from 4,000 to 1,000 students. Easing the path to university title for small institutions is expected to be a central feature in the government's responses to consultations on last year's Higher Education White Paper.

History of Progress

77-48211/419300 In memoriam of Samuel F. B. Morse (27.04.1791 – 02.04.1872)
# 06, June 2012
V.P. Samokhin
A brief review of main works and achievements of Samuel Finley Breese Morse is presented. He was an American artist and inventor, the creator of a new telegraphic scheme and code named after him - "Morse Code" that got the world recognition. Morse’s invention was a starting point for the development of wire communication technology in America and led to its spread in Europe and further to application of "Morse code" in radio communication (it is used in amateur radio communication even nowadays). Some biographical information of S. Morse is given, as well as some interesting facts about his life and work.
 
SEARCH
 
elibrary crossref ulrichsweb neicon rusycon
Photos
 
Events
 
News



Authors
Press-releases
Library
Conferences
About Project
Rambler's Top100
Phone: +7 (915) 336-07-65 (строго: среда; пятница c 11-00 до 17-00)
  RSS
© 2003-2024 «Наука и образование»
Перепечатка материалов журнала без согласования с редакцией запрещена
 Phone: +7 (915) 336-07-65 (строго: среда; пятница c 11-00 до 17-00)