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scientific edition of Bauman MSTU


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

# 03, March 2012

Science and Education
77-30569/345402 Adaptive neural network regulator to control piezoelectric rotation engine
# 03, March 2012
A.A. Bokov, A.A. Boshlyakov, V.V. Ivanenkov
This article deals with selecting and creating a control system of a mechatronic modular unit based on piezoelectric rotation engine. The authors consider the features of a piezoelectrical engine as a control object and justify the choice of the neural networks technology. The authors carry out a synthesis of the adaptive neural network regulator and simulation in MATLAB of the whole system. The efficiency of the synthesized regulator is shown.

Machine Building and Engineering Science

77-30569/362271 Calculation of the required number of processing equipment while designing production facilities under conditions of multiproduct manufacturing
# 03, March 2012
I.L. Volchkevich
The author proves the urgency of designing production facilities for multiproduct manufacturing and describes a methodological approach to calculation of the required number of equipment subject to time consumption in alignment procedures and rejection of replenishing. The analysis of NC machinery functional status is presented. The author proposes hypotheses of machining time per detail dependence on refining time and age related realignment. The results can be used for designing production facilities and planning manufacturing programs for NC machinery facilities.
77-30569/362645 Detection and analysis of organizational-technological factors influencing the productivity of technological systems based on processing-assembly concentration
# 03, March 2012
S.A. Bysov, E.N. Malyshev
The authors determine organizational and technological factors influencing productivity of technological systems based on processing-assembly concentration. The authors analyzed these factors and presented a mathematical model showing savings on time for manufacturing on the basis of processing-assembly concentration.
77-30569/354165 Application of numerical simulation technique in investigation of efficiency of the motorsport engine piston piston jet cooling system
# 03, March 2012
L.L. Myagkov, Yu.V. Mihailov
In this article an oil jet cooling system for heavy-duty piston is presented. The influence of oil flux, nozzle diameter, number of injectors and its inclination on cooling efficiency was established by means of numerical simulation in ANSYS CFX. An optimal combination of parameters was chosen with a maximum heat transfer coefficient criterion. Transient thermal analysis of the piston was conducted. It was established that usage of oil cooling made it possible to reduce the maximum temperature in the piston by 73,7°C and 50,3°C in the first ring groove. Thus, prolonged service life of pistons could be obtained.
77-30569/347459 Methodology of improvement of industrial production’s technologies and creation of new methods of treatment
# 03, March 2012
DOI: 10.7463/0312.0347459
V.M. Yaroslavtsev
Basic positions of methodology of creation of high-effective technologies and research of new methods of treatment were considered. Systematization of ways to improve the machining, built on the basis of generalization of experience of the solutions of technological industrial problems and scientific achievements in the field of the cutting theory was brought. By the example of machining, the effectiveness of practical use of this methodology was shown.
77-30569/342101 Analysis of effectiveness of various personal body armor
# 03, March 2012
A.L. Galinovsky, V.I. Kolpakov, S.G. Mulyar
The authors consider the problem which describes high-speed interaction of an inert compact striker with various kinds of obstacles, including combined type barriers. The purpose of the study is, with the aid of mathematical modeling, to find out, what types of obstacles are capable of withstanding high-speed blow. They can be used as armor elements in personal body armor. Mathematical modeling of the process was done in Ansys 12.1 IDE. During the modeling of a high-speed interaction process a continuum mechanics device in two-dimensional axisymmetric setting was used. The authors developed and tested the mathematical model and drew conclusions concerning applicability of the armor elements.
77-30569/325485 Features of interaction of laser radiation with transparent dielectrics.
# 03, March 2012
A.G. Grigor'yanc, M.A. Bogdanova
This work is dedicated to key specifications of laser emission and ways of their application for labeling transparent dielectrics. On the basis the analysis of literature data and studies of all possibilities of applying laser emission for labeling different materials, the authors propose to investigate the influence of emission wavelength on the size of the obtained defect inside the material, and also to conduct some studies regarding the possibility of applying the existing methods for concrete equipment.
77-30569/315859 Analysis of deflected mode (DM) of three-disk plane of almost instantly changeable system
# 03, March 2012
M.V. Astahov, A.B. Nikishkina
When designing constructions it is important to control the internal forces in order to produce machines and constructions with a rational mass. Such control is possible with the help of tracking tightenings produced on the basis of almost instantly changeable systems. The article is dedicated to the analysis of deflected mode of a three-disk flat almost instantly changeable system for the purpose of its usage in tracking tightening. The change of forces which appeared in the rods was considered depending on the angle of inclination of one of the rods in the system and on the external force time variable.

Constructional Material Processing in Machine Building

77-30569/341732 Formation of tap failures
# 03, March 2012
A.E. Dreval', A.V. Litvinenko
The article presents the results of experimental studies of physical phenomena occurring during threading structural steel 45 with taps. It was experimentally confirmed that the greatest relative loads are on the cutting profiles located at the base of the cutting cone. This fact determines their more intense wear. The article includes the analysis of changes in the cutting profiles in the radial direction, changes in transition of the main and minor cutting edges and their corner radius. The authors developed a generalized dependence of tap wear rate in major-diameter.

Power Machine Building, Metallurgical Machine Building and Chemical Engineering

77-30569/347727 Optimization of geometric parameters of NM oil pump volute
# 03, March 2012
V.O. Lomakin, A.I. Petrov, A.I. Stepanyuk
In this paper the authors describe a technique of multi-criteria optimization of geometrical parameters of a retractor in the main NM oil pump. The optimization is based on the LP-tau search method; the test points are analyzed by the technique of numerical simulation of fluid flow inside the volute. An example of optimization of the volute of the NM3600-230 pump is presented. Minimization of head loss in the retractor and minimization of the radial load on the pump rotor were taken as optimization criteria. The variant of the flow part, which differed from the original one by smaller loss of the pressure head and significantly decreased load, was obtained as the result of optimization.

Transportation, Mining and Construction Machine Building

77-30569/404548 Aerodynamic properties of various constructive solutions for fan installations
# 03, March 2012
A.S. Terehov, A.P. Petrov, K.A. Petrov
The authors present an analysis of several fan installations and consider their aerodynamic characteristics under condition of air stream during car motion and fan operation. The advantages and disadvantages of these installations were considered. Fan installation with hot-performance capabilities in all car operation modes was developed.
77-30569/347783 Comparative performance analysis of continuous and relay control systems for the suspension bracket of multi-wheeled vehicles
# 03, March 2012
M.M. Jileikin
In the contemporary world motor industry due to the increase in operational speeds and use of pneumatic and hydro-pneumatic suspension brackets there is a tendency to a wider distribution of adjustable and operated suspension systems. Many factors influence the functionality and quality of controlling the suspension bracket: they are accuracy of measurement and transfer of parameters used for calculation of control; accuracy of working off the control by executive powers; system speed, i.e. the time passing from the moment of gauging of parameters till the moment of control realization. The author proposes a performance test of continuous and relay control systems for a suspension bracket of multi-wheeled vehicles. A comparative estimation of efficiency of the specified control systems was carried out, and optimum areas of applicability of both algorithms were specified

Mathematics and Mathematical Modeling

77-30569/358973 On cryptographic properties of generalized cellular automatons
# 03, March 2012
P.G. Klyucharev
The author introduces a family of Boolean functions which can be used as local transition functions in generalized cellular automates for usage as part of stream cipher. The functions from this family are balanced. Функции из этого семейства являются равновесными, их нелинейность близка к максимальной. Each of these functions is a complete system and allows to prove the lower bound estimate of the length of the output sequence of the generalized cellular automaton. These properties are important for cryptographic applications of generalized cellular automatons.
77-30569/325628 Hybrid algorithms for vector optimization in computational diagnostics systems
# 03, March 2012
V.D. Sulimov, P.M. Shkapov
Novel hybrid multiobjective optimization algorithms are presented for solving problems of computational diagnostics. A vectorial variant of the linearization method is implemented. Global solutions for individual criteria are determined by use of hybrid algorithms that combine the Metropolis algorithm scanning the space of variables and deterministic methods for local search. The vector optimization algorithms generate a set of non-dominated solutions to approximate a Pareto-optimal front. Simulation results for one of the benchmarks and corresponding valuations of the algorithm computational efficiency are received. The proposed hybrid algorithms can be applicable for computational diagnostics systems, problems of intellectual models teaching, complex dynamic systems control, and other intellectual technologies.

Aeronautical and Rocket Space Engineering

77-30569/352636 Double-pulse flights to halo-orbits in the three-body problem
# 03, March 2012
F.V. Zvyagin
During preliminary ballistic design possible flights of spacecrafts (SC) to the neighborhood of collinear libration points of the Earth-Sun system with a monopulse scheme are usually considered. However, such a flight handler has significant radial restrictions of the obtained halo-orbit. The article presents the results of the study illustrating the possibility of extraction of a spacecraft to halo-orbit of an arbitrarily small radius as a part of a double-pulse flight from the Earth’s vicinity. The author provides results of numerical simulation which show that the total expenditure on the extraction with double-pulse schemes was significantly lower than the total expenditure on the extraction to the parabolic orbit from the waiting orbit.
77-30569/345773 Mathematic rollover model in LNG storage tank
# 03, March 2012
N.S. Korolev
The author considers approaches to creating a mathematical model for describing the phenomenon of rollover; the model consists of fast emission of liquefied natural gas (LNG) vapour from the storage tank when the emission was caused by mixing of LNG layers which have different temperatures. Quantitative results of LNG layers behavior in fueling system storage tanks in starting complexes are shown. The analysis of LNG parameters at refuiling in storage tanks allows to predict temperature and pressure levels and to avoid construction damages during operation.
77-30569/330645 Setup of numerical simulation of interaction between an explosive charge and several high-speed penetrators
# 03, March 2012
M.V. Markova, V.S. Soloviev
The authors present a review of works dealing with the problem of shock explosive initiation; this review covered shock pulses administered by a single high-speed penetrator or by a flow of several penetrators. Expressions describing particular cases of interaction between an explosive charge and two high-speed penetrators are included in the article. Feasibility of numerical simulation was asserted to be the principal research technique for studying such high-speed processes. Different numerical setups using the AUTODYN 2D and 3D hydrocode are considered. Reasons behind planar symmetry used in a two-dimensional setup are included in the article. The authors show good agreement between the results obtained using two-dimensional setup with planar symmetry and results obtained during three-dimensional numerical runs.
77-30569/326182 Additivity applied to shock and detonation processes in explosive mixtures
# 03, March 2012
M.V. Markova, V.S. Soloviev
The authors show the possibility of simple analytical evaluation of properties of multicomponent explosive mixtures with known properties and weight percentage of components. Expressions that expand the applicability of additivity laws were obtained from known shock wave theory relations for specific volume, density, isentrope exponent, explosive heat, detonation speed of explosive mixture. The authors provide a technique of calculation of detonation properties of explosive mixtures for a general multicomponent explosive, for two-phase medium and for a mixture of explosive and inert additive. An analytical shock adiobatic curve of a multicomponent explosive could be easily derived from the obtained results. This may be particularly useful for estimation of detonation process behavior in explosive mixtures when there is no experimental data concerning their particular properties.

Instrument Engineering, Metrology and Information-Measuring Devices and Systems

77-30569/342346 Real-time waveform envelope processing in autonomous information systems
# 03, March 2012
V.K. Hohlov
 The article describes the possibility of obtaining waveform envelope readings of input implementations using the Hilbert conjugated process which can be used as informative parameters of the signals that are invariant to the energy spectrum medium frequency with a relative width of the band to 0.7-0.8. In this case automatic tracking of the sample rate is performed according to the changing medium frequency of the input implementation energy spectrum.
77-30569/327254 Observability research of the azimuthal orientation error and instrumental errors of the three-axis gyrostabilizer of the radio telescope inertial orientation system
# 03, March 2012
Yu.G. Egorov, S.V. Smirnov
The radio telescope inertial orientation system is based on using the method of autonomous azimuthal orientation by means of currents measured in horizontal correction channels with the azimuthal rotation of the gyroplatform. The authors studied observability conditions of azimuthal orientation error and instrumental errors of a three-axis gyrostabilizer with constant and variable command precession around vertical axis.
77-30569/326698 Laser reflectometry method of measurement of thickness of gold nanofilms on quartz substrate
# 03, March 2012
V.A. Gorodnichev, M.L. Belov, A.M. Belov, S.V. Berezin, Yu.V. Fedotov
 In this paper the authors consider a laser reflectometric method of measurement of thickness of metallic films on dielectric substratewas. Optimal wavelengths for measuring thickness of gold nanofilms on quartz substrate were determined; error estimation for determining film thickness from laser reflectometry measurements was obtained. Mathematical simulation shows that the method allows to measure a gold nanofilm with thickness from 1 nm to 5 nm using wavelength 1310 or 1550 nm with mean error ~ 0,15 % and with thickness from 5 nm to 50 nm using wavelength 515 nm with mean error ~ 0,25 % and the relative root-mean-square value of measurement noise 1 %.

Radio Engineering and Communication

77-30569/352332 Influence of RLC laser parameters on data transmission speed in high-power optical transmitters
# 03, March 2012
N.S. Novikov, I.V. Kryukova, N.N. Chukovskii
This article describes a method of increasing the data transmission speed in open optical communication lines, namely the method of increasing the current modulation frequency of a powerful semiconductor laser. In this paper it is shown how the laser case influences the speed of data transmission; the advantage in transmission speed when using the laser in a smaller package is also shown. The authors propose new methods of measurement and calculation of the RLC laser emitter parameters; equations for calculation of the RLC-parameters with known values of the impedance, as well as the calculated values of RLC parameters for two investigated lasers are also given in the article. Quantitative estimations of the influence of RLC parameters on the bandwidth of the laser are included in the conclusion.
77-30569/254905 Development of software for effecency simulation of technical solutions, used in radars.
# 03, March 2012
S.I. Nefedov, Yu.S. Nefedova, G.P. Slukin, E.Yu. Ivat'ko, A.A. Karankevich
The article describes development of multipurpose software package for computer simulation which allows to objectively evaluate the effectiveness of any technical solution used in radars. The authors consider a structural scheme of the developed software and its components and describe the results of a simple simulation.

Informatics, Computer Science and Management

77-30569/380497 Analysis of approaches to password system selection for protection of LAN servers when connecting Net users
# 03, March 2012
V.M. Gasov, V.M. Postnikov
This article deals with the analysis of approaches to the formation of password system for protection of LAN server when connecting user network. Based on the demands of information security, main functions of password system for protection of server were identified. Set of main components of password system was determined; it consisted of length of password, password’s alphabet, password’s expiration date, unicity of password and variants of password’s blocking modes. Analytical expression for evaluating the required length of password, which guaranteed the certain given level of probability of guessing password considering speed and time of guessing, and also the alphabet of password, was presented in the article. In order to provide the required level of information security, practical recommendations on the formation of password system for protection of LAN server when connecting user network were given.
77-30569/376455 Synthesis of optimal control systems for dynamic objects with random initial values
# 03, March 2012
K.A. Pupkov, Xuan Phang Pham, A.I. Diveev
 The authors formulate a problem of control systems synthesis for dynamic objects with random initial values. It was proposed for the synthesis to modify functionals of quality to form sum of values with weights for each initial value. Weights determine probabilities of initial values.  It was proposed to use the numerical network operator technique for solving the synthesis problem. An example of control system synthesis for an aircraft at the descend stage is presented in the article.
77-30569/372760 Methods of presentation and basis signal transformation in generalized Christenson functions
# 03, March 2012
V.V. Syuzev, A.Ya. Savel'ev, D.Yu. Gudzenko
 The authors consider methods of synthesis and basic properties of various discrete basis systems of generalized Christenson functions in polybasic number systems, as well as the original scalar method of constructing fast algorithms for analyzing the spectrum in these bases. Theoretical results are illustrated with concrete examples.
77-30569/367724 Admissible spatial trajectories of the unmanned aerial vehicle in a vertical plane
# 03, March 2012
A.P. Krishchenko, A.N. Kanatnikov, S.B. Tkachev
Trajectory planning problem of the unmanned aerial vehicle (UAV) was considered in this article. UAV should flied by the preset traveling points during the preset moments of time. State and control variables were also restricted.The main problem is to find the permissible trajectory, which satisfy given restrictions. The approach based on design of a trajectory from a certain set of sample maneuvers was proposed. These maneuvers were formed with use of a combination of analytical methods of trajectories calculation, methods of mathematical simulation and various heuristic algorithms.The sequence of traveling points breaks required trajectory into segments. Essential simplification of the problem can be obtained by the demand that calculation of the trajectory segment does not affect on calculation of the subsequent segments and depends only on values of state and control variables of UAV obtained on the previous segment. In this case planning of a trajectory was carried out consistently, from one segment to another.In this paper the maneuver planning problem of an echelon change was solved. This maneuver in a combination with rectilinear uniform movement allowed to plan those segments of a UAV trajectory where movement can take place in the vertical plane, i.e. with constant value of a traveling angle.The nonlinear mathematical model of UAV movement as material point in the trajectory coordinates was described. The proposed method of the solution of a terminal problem was based on usage of polynoms on time. Two heuristic algorithms of maneuver planning of echelon change were described. Examples were included. Results of simulation and the scheme of testing of proposed planning method were presented.
77-30569/359383 Estimation of steganographic algorithms undetectability
# 03, March 2012
A.V. Remizov, M.V. Filippov
The authors propose formal criteria of estimation of steganographic algorithms in the context of undetectability of hidden information by the opponent. A method of creating optimal detection methods is also presented in the article. The article also contains the results of the analysis of known and prospective stenographic algorithms operation with the usage of methods constructed in this manner.
77-30569/355371 Approximation of integral mean estimations of transient regimes of simulated models of queuing networks
# 03, March 2012
V.M. Prihod'ko, D.V. Stroganov, P.S. Yakunin, E.S. Moskvichev, A.A Solncev
This article deals with the problems of estimation of the character of autocovariance functions and trends of typical output simulated processes, which are necessary when investigating the convergence of search optimization algorithms on simulated models. In order to determine the function class of output simulated processes, simulation of typical structures of queuing networks was conducted, namely disconnected single- and multi-phase queue systems with different service procedures and closed-loop single- and multi-phase queue systems with sources of various population and service procedures.
77-30569/345425 Approaches to identification of center-of-mass motion models in space rockets
# 03, March 2012
A.V. Proletarskii
The article considers methods of identification of center-of-mass motion models in space rockets. Reducing the task of identification to a two-point boundary-value problem is shown for the purpose of unification of program-algorithmic support in the control system.
77-30569/342044 Selection of state distribution function at the parallel test of the model
# 03, March 2012
I.A. Korotkov, V.A. Krishchenko
During testing finite discrete models to avoid constraints of available memory, parallel generation and distributed storage of state space can be used. The efficiency of such an approach depends on the choice of the state distribution function between computational nodes. The article considers the choice of this function, which allowed reducing the validation time at the expense of the number of removed callings between the nodes. The experiment results obtained with the help of the prototype of the tool for model validation are included in the article.  
77-30569/341367 Equations of sensitivity for the pulse system of cable insulation thickness stabilization with auxiliary adjustable variable at parametric discrepancy
# 03, March 2012
N.N. Kucyi, E.A. Osipova
Equations of sensitivity with respect to parameters of the controlled object were obtained. They allowed forming an automatic parameter optimization algorithm for the integral pulse-duration modulation system with two circuits at parametric discrepancy of a real object and its model. The pulse system of cable insulation thickness stabilization with an auxiliary controlled variable is considered.
77-30569/341170 The renovation process in Kalman-Bucy optimal filter
# 03, March 2012
S.L. Chernyshev
The author considers the renovation process in Kalman-Bucy optimal filter and proposes a solution of the differential equation for tracking error. It is shown that this solution includes normalized impulse characteristics. The expression for the renovation process correlation matrix is included in this article.
77-30569/339624 Distributed fault-tolerant DBMS
# 03, March 2012
D.N. Kovega, V.A. Krishchenko
The authors consider distributed fault-tolerant DBMS based on the Erlang runtime environment. As the result of testing, it was determined that the bundled software allowed achieving almost a linear growth of speed of query execution depending on the number of replication clusters. Recommendations on system deployment were produced.
77-30569/338840 About the way of measurement of temporal variations of Earth’s electric conductivity
# 03, March 2012
O.I. Miseyk
This author considers the design of a tuner of medium electric conductivity mounted in an anthropogenic impact zone. Correlations which allow determining the configuration of the position of primary transducer electrodes compensating the noise signal were obtained. A block scheme of the sensor which measures medium electric conductivity was proposed; compensation of signals of the noise field and the field of the undisturbed medium was implemented in the sensor.
77-30569/326903 Development of measurement system for aircraft based on algorithmic design approach
# 03, March 2012
K.A. Neusypin, A.V. Proletarskii, D.O. Sholohov
The problem of aircraft movement control with required accuracy at different segments of flight is usually solved with the usage of information from measurement system. The best structure of a measurement system was determined with the calculation and analysis of precision characteristics of measurement systems.


77-30569/311032 The analyses of natural frequencies of the bridge structures in the process of crippling
# 03, March 2012
N.N. Scheglova
This article deals with the problem of marker determination; these markers allow to locate hidden fractures in individual bridge spans. The frequency method for investigation of oscillation in systems with distributed parameters was used for the analysis. A known mathematical model – the model of pin-ended beam with point load - was used because additional weight would lead to the decrease of the main natural frequency, just like a fracture would do in this place. The decision analysis of the wave equation allows to identify dependences of changes in the first six frequencies subject to the place of critical section. A set of values of frequency reducing on different harmonic components could be regarded as an attribute of the critical section area. This conclusion may be of significant practical importance when analyzing results of bridge monitoring.
77-30569/310721 Numerical simulation of cylindrical-conical barrels’ interior ballistics with plastic projectile body
# 03, March 2012
N.V. Bykov, V.S. Vladimirov, Val.V. Zelencov
The authors consider numerical simulation of interior ballistics of cylindrical-conical barrels and describe mathematical models of propellant and plastic medium in mass Lagrangian coordinates. The numerical solution was obtained by using a simplified Neumann finite-difference scheme. It is shown that the use of a cylindrical-conical barrel with a plastic body allowed to increase the initial velocity of the projectile by about 1.5 times compared to classical schemes.

Electrical Engineering

77-30569/347501 Features of formation of infrastructure and marketing outlets of energy resources on the basis of small maiden natural gas fields
# 03, March 2012
V.K. Aver'yanov, V.N. Tolmachev, V.A. Karasevich, A.A. Chelaznov, M.A. Juravskii
The article considers development of methodological foundation of the energy service market based on the usage of small non-developed maiden natural gas fields. The authors also study the factors which influence the demand for energy services in well-established engineering infrastructures of regions, as well as the creation of information databases and design procedures of fundamental circuit designs. On the basis of the developed approach the authors propose different variants of the most effective distribution of small-scale energy power-suppliers, of consumers using small gas fields as fuel for power-suppliers. The most important technological, financial and economic constraints, such as safe distances from production fields, electric energy and heat rates, the cost of technological linking to the electric network, acceptable payback periods etc. are also considered in this article.  

Power Engineering

77-30569/381537 Preliminary research of characteristics of various implementations of hybrid turbofan engines for short- and medium-haul aircrafts
# 03, March 2012
Yu.A. Ezrohi, S.M. Kalenskii, A.S. Polev, A.S. Drygin
 Existent estimation procedure for tractive-economical and mass-dimensional characteristics of turbofan engines was improved. The authors consider two schemes of hybrid turbofan engines with additional power input to fan spindle from an electric motor supplied with accumulators or fuel elements. For the first time in Russia characteristics of these schemes were evaluated at different capacity ratios of the fan drive between a low-pressure turbine and an electric drive. The authors present the results of thermodynamic calculations, speed and throttle characteristics of hybrid turbofan engines of both schemes. Conclusions were made on reasonable ranges of capacity ratios between the low-pressure turbine and the electric drive which are used for the fan drive.
77-30569/359008 Research of the working cycle of a closed gas turbine in a tri-generation unit operating on a sequential scheme
# 03, March 2012
A.N. Arbekov, S.A. Burtsev
The authors consider the scheme which they previously introduced in cooperation with A.I. Leontyev. It is a closed gas turbine tri-generation unit operating on a sequential scheme. The unit can simultaneously produce electric power, heat and cold (on specified temperature levels) ensuring conditioning and/or thermostatic control. The results of the research of its thermodynamic cycle with the assumption of realistic efficiency of unit components and non-zero temperature differences in heat exchangers are presented in the article. The authors define the field of reasonable rates of pressure rise in the compressor. The pressure increase provides high efficiency and small-scale dimensions and mass of the energy unit. The authors propose recommendations on choosing the rate of pressure rise in the compressor for design simplification of a closed gas turbine tri-generation unit operating on sequential scheme.

Metallurgical Engineering

77-30569/342193 Ab initio calculations of the electronic structure of Pd-Mn and Cu-Mn spin glasses: manganese clusters and a giant magnetic moment
# 03, March 2012
V.S. Kraposhin, D.I. Bajanov, P.V. Bocharov
In the framework of the density functional theory ab initio calculations of free energy at 0 K, electron density and magnetic moments were performed for Pd-Mn and Cu-Mn spin glasses. It was assumed, clusters consisting of two, three or four Mn ions existed in solid solution thus forming dumbbells, triangles or tetrahedrons respectively. Clusters stabilize solid solutions in all cases, while the magnitude of the magnetic moment is dependent on the cluster structure. In Pd-Mn solutions the highest value of the giant magnetic moment per Mn ion (7,2 Bohr magnetons) corresponds to Mn tetrahedron with the sequences of Mn-Pd-Pd-Mn as the tetrahedron edges. In Cu-Mn solutions the highest value of the giant magnetic moment (4,2 Bohr magnetons) corresponds to a single Mn ion. It was established that fields of solid solutions in Pd-Mn and Cu-Mn systems corresponded to the states of the colloidal solid solution.
77-30569/330564 Influence of thermomechanical treatment parameters on the phase-structural condition of alloy V-4Ti-4Cr
# 03, March 2012
T.Yu. Yudina, E.V. Bazaleev, K.O. Bazaleeva
The authors studied the influence of annealing temperature and degree of cold plastic deformation on the phase-structural condition of alloy V-4Ti-4Cr. By the changing of the lattice period of the vanadium solid solution it was shown that the increase of the annealing temperature to 1400 °С resulted in dissolution of vanadium primary oxicarbonites. Subsequent deformation allows to raise the hardness of the alloy more than twice at the expense of stress aging. Besides, it was revealed that at the degrees of deformation more than 40%, the mechanism of deformation in alloys changes from dislocation to twin.
77-30569/330997 Optimization of technology factors of complex-alloyed steel vacuum nitrocarburizing
# 03, March 2012
M.M. Lashnev, M.Yu. Semenov, A.E. Smirnov
An experimental study of carbon and nitrogen saturation of complex-alloyed steel in low-pressure atmosphere was conducted. After the process of vacuum nitrocarburizing the quantity of austenite was increased. Also the dimensions of carbonitride particles were decreased. The control factors of vacuum nitrocarburizing technology were optimized with use of a mathematical model.
77-30569/330611 Investigation of the processes of laser doping of aluminum alloy surfaces
# 03, March 2012
T.V. Tarasova, G.O. Gvozdeva
This paper presents an analysis of scientific information on the experiments carried out in the field of laser doping of aluminum alloy surfaces with various components in a wide range of treatment modes with different types of lasers. The authors analyzed laser alloying of aluminum alloys with non-metallic components, laser alloying of aluminum alloys with metallic components and laser alloying of aluminum alloy with compounds. It was found that laser alloying of aluminum alloy with metal components, their mixtures and alloys increases surface performance. A distinctive feature of the structure formation of doped zones of aluminum alloys is high satiation of solid solution which exceeds solubility under equilibrium conditions as well as formation of intermetallic compounds. It is shown that there is a real possibility of laser hardening of aluminum alloys: by changing the parameters of the surface treatment with a pulsed or continuous laser beam one can control the characteristics of doped zones, such as size, concentration, saturation components, structure, and microhardness.
77-30569/330069 Constructions of algebraic geometry and simple polyhedra which are not stereohedra for clathrates and have 24 vertices and 14 faces
# 03, March 2012
A.L. Talis, V.S. Kraposhin, I.N. Veselov, I.A. Ronova, O.A. Belyaev
The authors show the existence of special polyhedra (clusters) and combinations of polyhedral, which are the structural implementation of algebraic geometry constructions. An algorithm of graph derivation corresponding to a special class of simple polyhedra with 24 vertices and 14 faces was considered for the case when these polyhedra have 4-, 5- and 6-gonal faces. The graph was derived for the first time for the polyhedron with one tetragonal face and which is not a parallelohedron. Polyhedra of this class allowed to determine the possibility for 14-verticed canonic and non-canonic Frank-Kasper polyhedra to be presented in the structure of intermetallics. This approach allowed to determine the symmetry of wide spectrum of ordered (not necessary crystalline ones) tetra-coordinated (diamond-like, clathrates) and tetrahedral (metallic) structures larger, including also nanostructured states.
77-30569/330149 Laser cladding application for elimination of defects on titanium-alloy samples
# 03, March 2012
E.V. Popova, T.V. Tarasova, I.Yu. Smurov, B.S. Sarbaev
Experimental studies of bond strength using the standard method of GOST1497-84 on titanium alloy specimens (Ti6Al4V) were conducted. The crack was simulated on the samples, then it was cladded using laser treatment and determined the destructive load for each sample. According to test results the optimal cladding parameters were chosen so that mechanical properties of the specimen with a cladded crack practically did not differ from the intact sample (the value of the destructive load for cladded sample was Pmax = 62,8 kN, while for the intact sample Pmax = 63 kN). Failure occured far from the cladded area.


77-30569/332441 Research of insulation defects and charge defects of gate dielectric of MOS structure with Al and liquid electrodes
# 03, March 2012
V.E. Drach, I.V. Chuhraev
In this article the authors present the results of statistic measurements of the injection voltage and the charge-to-breakdown injected into a gate dielectric. MOS structures with different materials of the upper electrode were used as experimental samples. The authors propose comparative estimation of insulation defects and charge defects of SiO2-PSG film of MOS structures with Al and liquid electrode. The MOS structures with liquid electrodes, based on Hg and InGa eutectic compound appeared to be a good test for investigation of gate dielectric quality before production operation of metallization.

Education Sciences

77-30569/342803 Place of professional ethics in the system of engineering education
# 03, March 2012
E.A. Gavrilina, R.V. Komyagin
The authors consider the importance of courses related to formation of professional ethos. It was shown that in the modern world engineers often act as decision-makers not only in the spheres of engineering and technology but also in social and political spheres. The authors argue the danger of technocracy and demonstrate ways of overcoming it in the system of engineering education.

General Problems of Engineer Education

77-30569/330374 Practical quality control of MATE competition Project ROV-hydrobot’s in the competitive environment
# 03, March 2012
S.P. Severov
The author shows that the result of higher engineering professional education in the form of a certified specialist who has knowledge, skills and professional communication skills, for example in the field of underwater robotics and marine industry, is the goal of a complex process of university education. In particular, the complex is characterized by Bauman MSTU taught subjects to 40-50 with the total number up to 9900 academic hours. Sufficient parametrized certainty of objectives can be considered as higher education in engineering design as a project, and all educational processes associated with them - as reasonable processes. The author argues that controlled management of a quality competitive, low-budget team project, which aims to create, within one year life cycle, an original student-submersible ROV- hydrobot, at world level of quality is complex. But it is a solvable problem for higher engineering professional education in Russia. The solution of this problem is achieved by organizing academic experience of students, optimization of dynamic flexible forms of organization, management skills current student role their real abilities, knowledge, abilities and skills in design and use of theory and practice of project management based on international standards.

Foreign Education

SOUTH AFRICA: Technology Director Turns Cellphones Into Classrooms
# 03, March 2012
For students in South Africa, mobile phones aren't just for texting. They're often the surest route to the Internet, especially for the many who have little or no reliable computer access off campus. And, as in much of Africa, cellphones are ubiquitous. A 2007 study found that 98.5 percent of the country's university students had one.Laura Czerniewicz thinks a lot about how students really use those phones in a higher-education setting. She's an associate professor of education at the University of Cape Town and the founding director of the Centre for Educational Technology.
BOTSWANA: American Universities to Explore Opportunities in Botswana
# 03, March 2012
At least 11 American universities, including Harvard, are visiting Botswana this year to explore possibilities of doing business there, the country’s ambassador to the United States, Tebelelo Seretse, has announced, writes Victor Muyakwabo for The Monitor.The first delegation arrived in Gaborone last weekend while another delegation was due to arrive on 5 March.Seretse said the American universities were going to explore possibilities of research and collaborating with local institutions through programme franchising, among other things. She explained that most of the US universities had long-term relationships with the Botswana government, which had been sending students to them over the years.

History of Progress

77-30569/347667 Gaspard Monge – creator of descriptive geometry
# 03, March 2012
V.K. Portnova
This article is dedicated to the life and activity of the French scientist who made an important contribution to the creation of Descriptive Geometry as a separate science. Gaspard Monge was a heavyweight among the scientists of Academy of Science as an organizer of higher education in France. He created Defense Industry and new technologies at his time. The aim of this article is to describe the structure of the course and the contents of the “Descriptive geometry” program, to explain the main directions of Monge’s ideas and also to illustrate his talent, activity and permanent dedication. This article is meant for the reading public and students of technical universities.
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