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scientific edition of Bauman MSTU

SCIENCE & EDUCATION

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

# 02, February 2014

Machine Building and Engineering Science

Basics for calculating the required machinery quantity under uncertainty conditions
# 02, February 2014
DOI: 10.7463/0214.0701227
I.L. Volchkevich
The article substantiates the urgency of the problem to estimate the industrial uncertainty factors in calculating the necessary equipment quantities when designing the manufacturing facilities in machinery building. It presents a new approach and a mathematical technique for calculating the necessary equipment quantity under conditions of multiproduct versatile manufacturing. The causes of internal and external uncertainties and methods for predicting their levels are presented. The article gives an example for calculating the necessary equipment quantities for the NC-machinery facilities. The approach proposed can be used in designing the manufacturing facilities of mechanical assembly production.
The problem of wear-resistant coatings quality
# 02, February 2014
DOI: 10.7463/0214.0697616
Mi.I. Abashin, A.L. Galinovsky, A.N. Eliseev, A.M. Pavlov, V.A. Moiseev
The article aims at solving a problem concerning the express evaluation of the wear-resistant nanostructure coatings quality using the method of ultra-fluid jet examination. Conducted research activities have shown that an intensity of the coating delamination from the substrate depends on the stress concentration level in the test sample. The proposed informatively methodological procedure of ultra-fluid jet examination will allow prompt estimation of physical-and-mechanical parameters and operational condition of coatings being deposited on samples and passed fatigue loading. The offered procedure can be effectively used for selecting the coating material, substrate, and efficient modes of application.
Kinds of initial billets in renovation technologies
# 02, February 2014
DOI: 10.7463/0214.0699990
V.M. Yaroslavtsev, N.A. Yaroslavceva
The paper shows that renovation may be considered as a part of all industrial and manufacturing processes one of the objectives of which is to increase the objet resource or extend its lifecycle. It conditionally divides the renovation technologies into extension and resource renewal technologies of the object under renovation as well as into industrial and resource extension technologies at the stage of manufacturing a new product. It is stated that initial billets in renovation technologies can be not only billets damaged during operation phase. The initial billets also may be products of blank and metallurgical manufacturing, a diversity of tangible objects and materials damaged in manufacturing or lost their performances while in operation.

Constructional Material Processing in Machine Building

On deformation of thin-walled parts while turning on the lathes
# 02, February 2014
DOI: 10.7463/0214.0700319
E.V. Arbuzov, A.D. Zhargalova, G.P. Lazarenro, V.I. Semisalov
The paper studies the overall picture of deformation of thin-walled parts while turning them on the lathes. Its objective is to define configuration and value of the process-induced deformations under turning conditions of mechanical engineering. The paper investigates the parts of class “tube” and “disk”. A solution of the problem under consideration uses computer simulation in ANSYS software environment. The study task is to estimate the prospects for concept development to machine the thin-walled parts with controlled deformation under “soft” turning conditions. The simulation has shown that the change of turning conditions within the studied intervals causes changing deformations of parts in the range from 0.1 to 3 values of tolerance zone. This result can be a basis to plan further activities in the field concerned.
Process modeling and ultra-precision machining technology development for flat reflectors using a diamond milling head
# 02, February 2014
DOI: 10.7463/0214.0699743
S.V. Grubyy, V.V. Lapshin
The article describes a discontinuous process to machine flat aluminum alloy reflectors using a milling head equipped with a single-point diamond cutter. A developed technology allows machining the parts of optical surface quality. The article analyses the kinematic scheme and presents the model to calculate the cutting forces and temperatures. It also offers schemes to determine the cutting length when machining the flat reflector. The proposed model-based data have been compared with the experimental study data from various sources. The experimentation part represents the flat reflector machining results achieved owing to developed technology. The tests have confirmed the technology effectiveness. The ways to improve the quality of machining have been outlined.
Analysis of indirectly measured cutting forces in turning metallic cylinder shells
# 02, February 2014
DOI: 10.7463/0214.0687971
K.E. Kondratenko, A.M. Guskov, M.A. Guskov, Ph. Lorong, G.Ya. Panovko
Measurement of cutting forces is an important component for development and validation of manufacturing processes. To use generally accepted direct measurement systems available for this purpose is often impossible. This paper suggests an indirect method to estimate the cutting force when turning a thin-walled cylindrical shell. The method is based on the displacement measurements of the flexible workpiece. Furthermore, when it comes to the flexible workpieces turning, cylindrical shells in particular, there is a need to use non-contact displacement sensors. This paper considers a specific manufacturing system in which two radial displacement sensors are located close to the free end of a cylindrical shell, the opposite end of which is rigidly fixed in a chunk of a lathe. Measuring the radial and the circumferential components of the cutting force is under study. The model has been developed in a quasi-static approximation. An experimental case has been analyzed using the proposed method. Optimization of the angular location of two displacement sensors has been proposed based on the idea of minimizing the condition number of the linear transformation matrix.

Power Machine Building, Metallurgical Machine Building and Chemical Engineering

Optimization of Design of Steam Turbine Exhaust Conduits
# 02, February 2014
DOI: 10.7463/0214.0699887
A.S. Goldin, V.V. Korotkov
Research aims are to decrease the hydraulic resistance of exhaust conduit of steam turbine, reduce the flow irregularity at the conduit outlet, and equalize the steam flow before the condenser tube bundle. The conduit models and flows in it have been simulated in Solid Works environment and its COSMOS Flo Works application. The article presents the research results for the initial conduit model and modified design versions. To evaluate a degree of flow irregularity the momentum factor (Bussinesku factor) has been calculated for outlet cross-section of the selected conduit design. The analyzed research results made it possible to find an optimum design of the exhaust conduit. Introducing the suggested alterations in the conduit design will enable to improve heat exchange in condenser, to increase reliability of the tube bundle operation, to decrease noise and power losses as well as to rise turbine plant efficiency in general.
Renkin's organic cycle and its application in alternative power engineering
# 02, February 2014
DOI: 10.7463/0214.0699165
G.V. Belov, M.A. Dorokhova
The paper reviews some important aspects concerning the low-potential energy utilization using so- called organic Rankine cycle (ORC). The recent increasingly frequent applications of ORC are as follows: thermal waste treatment in industries, thermal power of combustion engines, solar and geothermal power engineering, biomass energy, etc. Significant attention is given to issues of working fluid selection. There is a list of the most important requirements for the working fluid. The paper presents the analysis of references, which examine different aspects of ORC applications and reviews the possibilities of ORC modeling.

Mathematics and Mathematical Modeling

The covering method for the solution of terminal control problem
# 02, February 2014
DOI: 10.7463/0214.0699730
V.N. Chetverikov
The paper proposes a new method to solve the terminal control problem for dynamical systems. The method is based on the complement of initial system by equations for the derivatives of the control and on the reformulation of the terminal control problem into two associated Cauchy problems. It is shown that this method is applied to the flat systems and generalizes the previously used approach. Here, the solution of the terminal control problem lies among the solutions of an arbitrary determined system of ordinary differential equations of appropriate order. This feature of the new method can be used for control design in the case of flat systems taking into consideration the constraints. In addition, an example is given to demonstrate the possibility to apply this method to the non-flat systems.
A local search with smoothing approximation in hybrid algorithms of diagnostics of hydromechanical systems
# 02, February 2014
DOI: 10.7463/0214.0699149
V.D. Sulimov, P.M. Shkapov
This article deals with the global optimization issues on the computational diagnostics of hydromechanical systems. The criterion functions are assumed to be continuous, Lipschitzian, multiextremal, and not always differentiable. The article proposes two novel hybrid algorithms with scanning a search space by the stochastic Multi-Particle Collision Algorithm that uses the analogy to the absorption and scattering processes for nuclear particles. The local search is implemented using the hyperbolic smoothing function method for the first algorithm, and the linearization method with two-parametric smoothing approximations of criteria for the second one. There are some results on the model solution of computational diagnostics of the coolant phase composition in the reactor primary circuit.
About one method of extension operator construction
# 02, February 2014
DOI: 10.7463/0214.0697588
E.M. Popova
This article examines S.L. Sobolev anisotropic spaces. It proposes a method to construct the operator extension T from the banach space of functions to Sobolev anisotropic space. The operator T is the best one in terms of growth rate of high order derivatives from extension function, and its construction is based on any extension operator Ext. The construction method is to apply the approximation operator saving boundary values to the operator Ext. V.I. Burenkov offers this method in the isotropic case while E.M. Popova’s proposal is to use it in the anisotropic one.

Aeronautical and Rocket Space Engineering

Contemporary methods for realization and estimation of efficiency of 3D-audio technology application for sound interface improvement of an aircraft cabin
# 02, February 2014
DOI: 10.7463/0214.0699177
O.N. Korsun, G.A. Lavrova
The paper concerns one of new ways to improve the interface of a modern aircraft cockpit, namely a 3D-audio technology application. The 3D-audio is a technology that reproduces the spatially directed sound via earphones or loudspeakers. Spatial audio-cues together with information about a danger, which also point out the direction it emerges from, can reduce the time of response to the event, thereby increasing the situation safety of flight.The offered paper describes the approved methods to implement the 3D-audio technology. It also presents results of experiments on evaluating the accuracy characteristics of localized directions towards the sound source for some types of audio signals.A scientific novelty is to achieve the true-to-life quantitative characteristics of 3D-audio technology to be appropriate for the modern aircraft cockpit interface design.
Influence of jet thrust on penetrator penetration when studying the structure of space object blanket
# 02, February 2014
DOI: 10.7463/0214.0699035
N.A. Fedorova, V.A. Veldanov, A.Yu. Daurskikh, S.V. Fedorov
The paper presents calculations to determine a penetration depth into low-strength soil targets provided by penetrators equipped with the pulse jet engine when studying a structure of space object blanket. In movement the penetrator is considered as a rigid body of variable mass, which is subjected to the drag force and the reactive one applied at the moment the jet engine fires. Dynamics of moving penetrator with its conic nose part is described with binomial empirical law of target drag force and with assumption that the jet thrust force is constant during its application time. It is established that penetration depth into low-strength soil target can be several times increased owing to use of the jet engine. A rational time for the jet engine firing and operation is defined.

Instrument Engineering, Metrology and Information-Measuring Devices and Systems

Reliability analysis of onboard laser ranging systems for control systems by movement of spacecraft
# 02, February 2014
DOI: 10.7463/0214.0699720
E.I. Starovoitov
The paper purpose is to study and find the ways to improve the reliability of onboard laser ranging system (LRS) used to control the rendezvous and the descent of spacecraft. It analysizes the key factors influencing the reliability LRS. The basic assumption is that the number of pulses of pumping diodes determines the solid state laser resource. The paper investigates a reliability function of LRS affected by the pulse repetition frequency, that depends on the measurement error of approach velocity and distance between the spacecrafts. The paper gives a quantitative evaluation of increasing the reliability function owing to the developed methods to detect a passive spacecraft using LRS with no optical-mechanical scanner.
Сomparative analysis of wind correlation lidar sounding range in UV, visible band and near IR bands
# 02, February 2014
DOI: 10.7463/0214.0696580
S.E. Ivanov, P.A. Filimonov, M.L. Belov, V.A. Gorodnichev, M.B. Mikhailovskay
The paper presents a comparative analysis of the sounding range of wind correlation lidar in ultraviolet, visible, and near infrared spectral bands. It shows that a visible spectral band is the most advanced one to provide a maximum sounding range of wind correlation lidar in earth atmosphere. If there are specific requirements for wind correlation lidar, for example, a requirement is that a wind correlation lidar should operate at the eye-safe laser sounding wavelength then the efficient work of wind correlation lidar may be maintained in ultraviolet and near infrared spectral bands with the sounding range reduced a little bit.
A principle for the noninvasive measurement of steady-state heat transfer parameters in living tissues
# 02, February 2014
DOI: 10.7463/0214.0695233
S.Yu. Makarov
The article describes a principle that may become a regular basis to use the noninvasive methods to measure parameters of steady-state heat transfer in living tissues, excluding the influence of unknown parameters such as biological heat sources and blood temperature. It presents a theoretical analysis and examples to implement the set out principle and proves technically a possibility to use this principle to determine the heat conductivity and perfusion of blood in human dermal epithelium. Furthermore, the article shows that the noninvasive determination of other parameters of biological tissue that influence on the steady-state heat transfer is possible.
Forming the Selection Functions in the Pulse Doppler Radar Information Systems with Random Signal Phase-shift Keying
# 02, February 2014
DOI: 10.7463/0214.0687918
V.K. Hohlov, K.P. Likhoedenko
The article presents a method to form the non-periodic selection functions in the short-range coherent pulse Doppler radar information systems with random signal phase-shift keying (manipulation) in transmitting and heterodyne channels. It studies statistical characteristics of Doppler signals received when reflecting from the point object that is located inside the first and arbitrary remote strobes at synchronized random carrier phase-shift keying in transmitting and heterodyne channels. The article shows an expansion of the relative bandwidth of energy spectrum of a Doppler signal received after reflecting from the point object from an arbitrary remote strobe, except for the first one. To form a non-periodic selection function is possible via the recognition method for the Doppler signal implementations using the relative bandwidth of energy spectrum and via the application of a regression tract to process intervals between zeroes of implementations.

Informatics, Computer Science and Management

Decomposition method for analysis of closed queuing networks
# 02, February 2014
DOI: 10.7463/0214.0700018
Yu.G. Nesterov
This article deals with the method to estimate the average residence time in nodes of closed queuing networks with priorities and a wide range of conservative disciplines to be served. The method is based on a decomposition of entire closed queuing network into a set of simple basic queuing systems such as M|GI|m|N for each node. The unknown average residence times in the network nodes are interrelated through a system of nonlinear equations. The fact that there is a solution of this system has been proved. An iterative procedure based on Newton-Kantorovich method is proposed for finding the solution of such system. This procedure provides fast convergence to solution. Today possibilities of proposed method are limited by known analytical solutions for simple basic queuing systems of M|GI|m|N type.
Software complex for finding the path routings in synchronous digital hierarchy networks
# 02, February 2014
DOI: 10.7463/0214.0698921
V.A. Bulanov, T.A. Bulanova, V.A. Trudonoshin
The paper addresses the communication network constructions based on the synchronous digital hierarchy (SDH) via software complex, which uses Dijkstra algorithm taking into consideration real network conditions. These conditions include dead ends, a standby link path along the fibres and equipment, which differs from equipment with passed main link, etc. The software complex enables us to find optimal main and standby routes for link in SDH network of complicated structure taking into account these restrictions. In addition to the path routings, complex enables saving information on the network nodes, sections, and links in database (DB) i.e., actually, it represents a DB with graphic interface, thereby allowing an operator to have rapid information on its state.
Parameter space normalization in General Hough transform
# 02, February 2014
DOI: 10.7463/0214.0697554
A.V. Bobkov
The paper considers an issue of object registration in the image through the generalized Hough transform with uncompensated geometric distortions being available. It proposes the method of geometric distortion correction and the method of parameter space normalization. The paper shows that the proposed algorithms require a relatively small amount of computations, but significantly improve the reliability of object detection. The paper may be of interest to professionals working in the field of pattern recognition as well as to graduate and undergraduate students attending lectures on the pattern recognition.

Mechanics

Influence of pores and filler articles in the binder on the composite thermal conductivity
# 02, February 2014
DOI: 10.7463/0214.0699772
I.Yu. Savel'eva
The article offers a mathematical model of heat transfer in a composite with spherical shape inclusions. The model takes into account that filler particles and pores are available in the binder. The effective thermal conductivity of such composite has been estimated, including the use of dual variation to formulate a problem of stationary thermal conductivity in the non-uniform body. The presented results can be used to predict the thermal conductivity of the composite affected both by fine-dispersed fillers introduced in the polymeric binding structure and by arising porosity when curing the binder.
Damages and resource of locomotive wheels used under the north operating conditions
# 02, February 2014
DOI: 10.7463/0214.0699140
A.V. Grigorev, V.V. Lepov
The Far North environment has extreme operation conditions characterized by the sharp changes of temperature which can reach ≥1000C on the surface of materials, depending on their reflecting power, with multiple transitions through a water freezing point. In the Far North environment such negative climatic factors cause an essential decrease in operation efficiency of technical constructions and equipment, including the railway transport. The article investigates a process of damage accumulation in material, describes an assessment technique for damage and resource of the locomotive wheel bandage that operates at low climatic temperatures. It also presents the calculation- and experiment-based technique to assess accumulation of damages and calculate resource of locomotive wheel bandage.
A model of nonlinear strain and damage accumulation in polymer composites
# 02, February 2014
DOI: 10.7463/0214.0687567
A.N. Ruslantsev, A.M. Dumanskii
This paper presents a model to predict a nonlinear strain of the carbon laminate; the model is based on the relations between the theory of laminated plates and the non-linear approximation of deformation curve of unidirectional layer at the shear in the layer plane. The explicit expressions of stiffness and compliance matrices were obtained via multiplying the matrices that correspond to the elastic characteristics by the matrices, considering the non-linear properties of the laminate. The paper suggests an approximation option for the non-linear properties of the layer at the shear using an exponential function. Some considerations on damage accumulation in carbon laminates were made.

Power Engineering

The electrohydraulic balance of the solar heat storage with autonomous power supply
# 02, February 2014
DOI: 10.7463/0214.0697540
M.K. Marahtanov, D.V. Duhopel'nikov, S.G. Ivakhnenko, V.I. Krylov
The paper considers an autonomous solar heat storage scheme with photoelectric cells for the hydraulic pump. It describes a method for calculating the power density of solar radiation during the day. To calculate the energy balance of the hydraulic system of autonomous solar collector the authors offer a methodology relevant for designing the similar systems. The curves obtained allow calculating the main parameters of the system components, including the required minimum area of absorber and photoelectric cells, pump power, water flow. The typical values of photoelectric cells area required for operation under typical environmental conditions were obtained.

Metallurgical Engineering

The application of vacuum heat and thermo-chemical treatment to improve strength of different heavily loaded machine parts and engineering instruments
# 02, February 2014
DOI: 10.7463/0214.0700036
A.E. Smirnov, M.Yu. Semenov
The paper presents great technological capabilities of vacuum heat and thermo-chemical treatment provided by the universal equipment, which enables us to strengthen different heavily loaded machine parts and engineering instruments. A load-bearing capacity of the treated part is defined by the diffusion layer saturation, the structure of surficial region and heart. Technological factors of treatment processes with complicated mechanisms to influence on the resulting features make it reasonable to design the strengthening operating conditions using the calculation methods.
Appendix

Foreign Education

UK Universities Facing Tough Global Competition in STEM Subjects
# 02, February 2014
The UK is ‘lagging behind’ in science and maths at university level, according to new international rankings.The annual figures from QS show that, while the UK is still performing strongly in the arts and humanities, it is falling behind in STEM subjects.Analysis of the rankings found that only three of the top 50 universities for civil engineering were in the UK, less than Hong Kong and Australia.
Swiss Universities Tested by Foreign Student Influx
# 02, February 2014
The rising influx of foreign students to Swiss universities is bringing more international talent to the country. But the debate on who foots the bill for welcoming such bright young minds is tying academics and legislators in knots.Switzerland prides itself on having some of the lowest tuition fees in the world, subsidised by the federal and cantonal authorities. This gives students access to higher education regardless of income, but taxpayers are also shelling out for foreigners.Top universities are now bulging at the seams with new students and frequently cry out for more cash to help them cope. At the same time, the proportion of overseas students is constantly rising -  from 23% in 1990 to 38% in 2011.Swiss universities jostle with international competitors to reel in the brightest overseas talent to boost domestic prowess in science, technology and other fields of research. In addition, business leaders welcome highly educated foreigners to help plug workforce gaps.
Higher Education Gets Another Online Challenger, as WEF Launches Its Own Web Courses
# 02, February 2014
On Jan. 22, the World Economic Forum announced the launch of its Forum Academy at its annual meeting in Davos, Switzerland. The initiative, started in partnership with edX as the platform provider, will begin in May with the opening course, Global Technology Leadership. According to WEF Chief Information Officer Jeremy Jurgens, who's leading the initiative, the idea is to put the WEF's huge network of industry leaders and opinion-makers at the disposal of a global audience.The WEF's launch of its academy is the latest in a number of increasingly popular online platforms that are moving to compete with traditional higher education institutions at a time when the cost of higher education in the United States is rapidly rising. Yearly tuition costs often reach $40,000 at American universities.
SOUTH KOREA: Pink Slip Handed to 'Bad Universities'
# 02, February 2014
The government of South Korea wants to shut down universities that cannot attract enough students. As a result, universities and colleges in South Korea are merging and reorganising as they fight for survival, writes Tomoko Tamasita for The Asahi Shimbun.South Korea saw an increase in the number of universities in the 1990s in response to societal demands for a better educated populace. At the same time, though, another problem emerged – some of these new institutions were just not cut out to survive as universities. In 2004, the government introduced a restructuring plan to tackle the issue of ‘bad universities’.
The Americanization of British Higher Education
# 02, February 2014
Britain’s grading system is broken. At least, that’s what critics are saying about the 200-year-old tradition of classifying undergraduate degrees into five categories, from first class to fail.In an attempt to improve the system, 21 universities started to experiment in November with an American-style grade-point average in hopes that it would be a better evaluation of students’ efforts and help solve grade inflation and other problems. A grade point average is calculated by adding up the grade points awarded to a student and dividing that total by the number of courses in which they were earned.But not everyone in British academe is on board. Some say the effort is flawed from the start and may contribute to the erosion of centuries-old methods that undergird higher education here.

History of Progress

David Sarnoff - godfather of Radio and Television (1891 - 1971)
# 02, February 2014
V.P. Samokhin, B.M. Kindyakov
A brief review of main works and achievements of David Sarnoff is presented, a native of Russia and the poor prominent American businessman, founder of the radio and television broadcasting. Provides information about parents Sarnoff, interesting facts of his life and work, including details of his work on the radio, including the rescue of passengers of "Titanic", the first in the U.S. broadcasts, creating corporations RCA and NBC and implementation of broadcast television. Sarnoff describes the service in the U.S. Army during World War II, work on creating RCA color television, his contacts with prominent Russian engineer Vladimir Zworykin and Leon Theremin, American inventor Frank Conrad and great Italian conductor Arturo Toscanini, as well as the nuances of the relationship with David Sarnoff Edwin Armstrong.
 
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