2014. № 76

Mathematics. Physics. Mechanics

Tarlakovsky D. V., Dang Q. G.

Mathematical modeling of non-stationary processes in saturated environment on model-based two-component environment is an important and urgent problem. Its urgency is dictated by pressing request of practice (extraction of groundwater, oil and gas, construction of earthen weirs, dams and earthworks, stability of slope, underground construction, etc.) and the need for further development of the general theory of multi-component environment, including questions of construction of mathematical models and basis of analytical and numerical methods for solving concrete boundary problems. Similar problems also find application in various areas of new technology, including problems of different apparatus landing of aviation, rocket and space technology.
Currently, in spite of major successes in this area, a lot of unsolved problems are remained. Especially, the problems of non-stationary interaction of deformable objects with grounds, elastic and multi-component environments are little examined. In connection with considerable mathematical difficulties in this area, there is a little number of analytical solutions, relating generally to the areas of canonical forms.
For modeling of dynamic processes in some grounds the model of elastic-porous Biot environment is often used. For the half-space filled by this environment, currently, the most of plane non-stationary problems are particularly researched. Thus, practically, there aren’t any analytical solutions to the corresponding axial-symmetric problems that are examined in this article.
The Hankel transform in radius and the Laplace transform in time are applied for solving. Originals are found by the theorems on the connection of plane axial-symmetric problems with use of known solutions to the first of them. Corresponding integrals are numerically found by use of their canonical regularization. Some results of the calculations are presented in graphical form.

Keywords: porous elastic environment, model Bio, half-space, surface influence function, the Laplace and Hankel integral transforms, communication and flat axial-symmetric tasks

Karpov V. V., Semenov A. A., Kholod D. V.

Purpose
Thin-walled shells are essential elements of many modern structures in various fields of engineering. The aim of this work is to study the strength of orthotropic thin shallow shells on the basis of a mathematical model, which takes into account lateral shifts, as well as the analysis of obtained results.
Design/methodology/approach
Modern materials (reinforced plastics, fiberglass, concrete, etc.) have a pronounced orthotropic property, i.e. material properties in various directions are different. Thus, to calculate the shells made of composite material often used theory orthotropic shells.
To examine the strength of the shell, it is necessary to analyze each loading step of stress-strain state of the structure. If for isotropic structure it is enough to evaluate the stress intensity, then for orthotropic and anisotropic it is necessary to compare the values of all the components of the stress with the limit values.
In this paper the results obtained with the help of geometrically linear version of shell mathematical model using an algorithm based on the Ritz method and iterative processes are presented.
Shown further solutions are obtained by holding the expansion of the unknown functions of 16 members by the Ritz method. Voltage values were calculated on the outer side of the shell.
Findings
For a variety of shell structures made of carbon fiber LU-P/ENFB, T300/Epoxy, M60J/Epoxy, T300/976 it is obtained the quantitative characteristics of strength and maximum permissible load required in the design of such structures. Results obtained by using the most accurate mathematical models of deformation of orthotropic shells taking into account the transverse shears. For considered shells, loss of strength occurs when voltage limit compression value achieved along the axis x.
Originality/value
The rapid development of technologies for the creation of composite materials allows to use their unique properties when creating shell structures: high strength, fire resistance, low corrosiveness, ease, etc. The renewed interest in the study of such structures is caused not only by the appearance of new advanced materials, but also by the development of computer technology, which allows to apply fairly accurate, time-consuming numerical methods and computational algorithms , as well as realistic visual technologies to present calculation results. Therefore, research in this area is quite relevant and justifiable work.

Keywords: shell, orthotropy, carbon plastic, strength, shallow shells, lateral shifts

Space technologies

Murlaga A. R.

An application of satellite systems for monitoring of the ionosphere from space after its artificial steerable disturbance is discussed in this paper. An arrangement of satellite group for continuous HAARP data acquisition is suggested. To solve the problem of HAARP monitoring, one must obtain an optimum value of a model function for the satellite group. This function depends on a set of variables (number of satellites in the group, quantity of information received from HAARP, an amount of costs, time for the satellite group developing). The purpose of this paper is to elaborate variable that was formerly defined as a set of the following characteristics: periodicity of HAARP activation, parameters of radiated signals (carrier frequency, signal polarization and modulation, frequency of modulation) and antenna array scanning angle. As a result of the investigation, one can see, that only frequency of modulation, periodicity of HAARP activation and antenna array scanning angle are of great importance and must constitute variable, while the other parts should be neglected. Moreover, the latter two have no effect on structure of the group neither on the orbit type, nor on the on-board equipment and are derived automatically if the frequency of modulation from HAARP radiated signal is detected. The variable defined in such a way that allows to optimize the model function and to optimize consequently satellite on-board equipment (now one is able not to use equipment in 2,8 — 10 MHz frequency range), to improve mass-overall characteristics of the whole system and to decrease its price.

Keywords: ionosphere, ionosphere heating facilities, HAARP, space system for monitoring, natural ELF/VLF antennas

Ponomarev A. A., Ponomarev N. B., Kirillov E. B.

The main purpose is to investigate the properties and features of free shock and restricted shock flow separation in supersonic nozzles. According to earlier articles on this subject, the main feature of the restricted shock separation is cap shock formation. Also the reverse flow zone is formed near the nozzle axis of symmetry. This fact was derived from indirect results and must be proved.
Overexpanded supersonic stream that flows from the nozzle is researched. The flow pattern of the stream is visualized and shadow pictures of the stream are obtained. A thick wire with small steel flags is placed perpendicular to the symmetry axis of the stream. Flags can rotate around the wire almost without friction. Such wire with flags is a good instrument to measure the direction of the velocity vector in different points of the stream. Two different nozzles are used. One of them has relatively small expansion ratio and is used to obtain free shock separation. Another one’s expansion ratio is significantly larger, so this nozzle is suitable to obtain restricted shock separation.
Experimental results show that flow velocity vector is directed away from the nozzle exit in all points of the stream in the case of free shock separation. The appearance of restricted shock separation really results in the formation of reverse flow zone near the symmetry axis of the stream. The stream flows around this zone as it is a solid obstacle. One can see that cap shock is formed.
In conclusion, we can say that restricted shock separation formation in high-area-ratio nozzles can result in great increasing of the amplitude of unsteady side loads and wall heat flux. Consequently, it is strongly recommended to carry out the liquid rocket engine tests in the conditions that prevent restricted shock separation formation.

Keywords: ionosphere, ionosphere heating facilities, HAARP, space system for monitoring, natural ELF/VLF antennas

Aerospace propulsion engineering

Batalov V. G., Stepanov R. A., Sukhanovsky A. N.

One of the important parts of gas turbine aircraft engine is nozzle. Mechanical and pneumaticalnozzles are wide spread and used for qualitative spraying of fuel. The spray should be uniform in azimuthal direction, with specified spray angle, structure and drop size distribution. Experimental study of two-phase flow characteristics in the nozzle spray is presented. It was shown that velocity field measurements by PIV (Particle Image Velocimetry) method have some specifics.The behavior of drops in a basic flow (air flow) strongly depends on the drop size. The velocities of relatively large drops with characteristic size of tens or even hundreds of microns are different from the velocity of main air flux. Whenconcentrationofsuchdropsishightheychangevelocitydistribution in the air flux.Thedropsizingwascarriedoutbydirectopticalmethodbased on pair of glare spots. Theessentialfeatureofproposedmethodisvalidationprocedure,thathelpto select pair of glare spots placed on one drop. Theprocedureofvalidationgivesnotonly reliable dataaboutdropsizesbutalso dropsvelocity distribution. Sowiththeuseofproposedmethoditispossibletostudydependencedropsvelocityontheir sizes and to reconstruct spatial distribution of flow rate. Thenumericalrealizationofproposed algorithm effectively scales for multiprocessor systems. Itrequiresonlyminimaladaptationforclustersoftware. Thispossibilityisveryimportantforanalysesofmultiplemeasurementsforrepresentativestatistics. Asaresultofourstudythesoftwarepackage "Programfordropsizinganddropsvelocitymeasurementsbytheir optical images"(sertificate of registry № 2013611440 от 09.01.2013).

Keywords: Particle Image Velocimetry, direct method of drop sizing, two-phase flow

Yakovkin V. N., Besschetnov V. A.

The breakdowns of a conical gear of gearbox sometimes occur in service of gas-turbine engines, resulting in shutting down the aircraft engine during the flight. The results of the study of one of these cases showed that the destruction has the fatigue nature. Usually the maximum vibratory stresses, located in gear, take place in modal oscillations with three or four nodal diameters. Detuning from resonance by changing the geometry variables is not always possible for this type of cog-wheels. The solution for this problem was suggested as the increase of the damping capacity of an element by adding a disk-shaped dry friction damper.
The contact interaction on surfaces with friction creates a nonlinearity of the problem, which is caused by the presence of coulomb friction. Modern design packages allow to take into account nonlinear contact interaction of full-scale models. However, contact problems, which deal with constrained or damped oscillations, still require a lot of computing resources. So, the main emphasis in the work was put at methods, allowing to evaluate the damping capacity of the structure more accurately.
The method of rapid assessment is based on a linear approximation of the sustained forced oscillations. The algorithm is implemented by calculating the eigen mode (modal analysis). The simulation of friction force is reproduced by the use of tangential springs. The level of damping of construction was calculated by the expended friction work.
The method of rapid assessment revealed the following: the optimum application force for the damper depending on the level of stress and the coefficient of friction; the stiffening effect of the damper on the damping capacity. The analysis of comparison study of the rapid computational assessment results with the experimental results showed the capability of achieving the satisfactory fit selecting the coefficient of dry friction and specifying the decrement of the gear oscillations without the damper.
The modified damper, damping capacity of which is considerably higher than in typical designs dampers, is also suggested in work. The effectiveness of the modified damper is demonstrated by the method of forced oscillations in transient analysis by taking to the account nonlinear contact interaction.

Keywords: coulomb-friction damper, conical gear, disk-shaped damper

Theoretical engineering. Mechanical engineering

Markovtsev V. A., Filimonov V. I., Markovtseva V. V.

The quality of aviation profiles, which are manufacturedby bendingfrom clad sheet blanks ofaviation alloys, largely depends on the width of the original piece.Obtaining minimum bend radii and thickening of the corner areas of bent profiles helps to increase thestiffnessof the structure of the aircraft fuselage frame.Therefore the paper considers the theoretical basis forthe development of a production line for the longitudinal and transverse cutting of the sheets of1163АМand В95пчАМ(the equivalentof 7075) aluminum alloys.After cutting the strips are usedfor manufacturing of aviation detailsby bending.
The paper presents the results of theoretical studies and calculations, which were aimed at determining the required width of the original piece. Those include the results of theoretical studies of the blankworkpieceparameters, which are presentedin the form of the appropriate formulas and graphs. These formulas and graphs can be usedduring the development of the technology for manufacturing of profiles by bendingfrom clad sheet aviation alloyblanks.
Principalresultsarethefollowing: the theoretical research has formed a basis that helped to develop the special equipment and tooling for longitudinal and transverse cutting of clad aluminum sheets and rolls.
The developed automated cutting complex allows to carry out the longitudinal and transverse cutting of strips from sheets and rolls of В95пчАМ and 1163АМaircraft aluminum alloys.The complex provides the high quality of edges and minimum width tolerances of the blank workpiece. Thisallows to attainthe width of theobtained strip that would be as close to the width of the flat pattern as possible.
Thecutting complexfacilitatesthe production of high quality aviation profiles by bending in accordance with theindustry standards. This in turn helps to increase the stiffness of the aircraft fuselage frame and reduceits weightby reducing the number of bended profiles and fasteners.

Keywords: cutting, aluminum alloys, stringer, fuselage frame, aircraft

Control and navigation systems

Shavin A. S.

Purpose:
the paper is devoted to development of mathematical model of information distortion in communication channels, as long as there are no noise stability and data transmission validity requirements for space rockets automated preparation and launching systems. The paper presents an approach to data transfer and hybrid interference simulation process.
Methodology/Approach:
the paper considers data transfer through RS-485 communication channel. Hybrid interference is a sum of additive white Gaussian noise and random pulse interference. A change of pulse interference instantaneous amplitude follows the normal distribution law, and pulses occurrence instants of time — Poisson distribution. As a simulation instrument the author uses methods of probability theory, such as formula of total probability, 2-D distribution laws, joint and independent events features, probability densities composition.
Results:
The developed model reflects bit error probability dependency upon communication channel parameters and noise characteristics.
Practical relevance: the key parameter to digital data transfer systems noise stability evaluation is a single symbol distortion probability. The developed model can be implemented to form noise stability requirements for communication channels, as well as to develop recommendations on noise-immune codes for automated preparation and launching systems, since data exchange fidelity provides for stability and continuity of space rockets preparation and launching processes.
Originality/Significance: the suggested model has convenient form for future upgrading, as well as testing its adequacy by either computer or full-scale experiment.

Keywords: automated preparation and launching system, communication channels, serial interface, bit error probability, additive white Gaussian noise, impact noise

Electrotechnology. Electromechanics

Shevtsov D. A., Turchenko I. S.

Three-phase stabilized (regulated) rectifying units are the key converter elements for modern highly reliable aircraft power supply systems.
The problem of ensuring an output voltage regulation has different circuit solutions, which can be realized using both semiconductor (transistor and thyristor) and magnetic switches (particularly high-speed single—wound saturable inductors (SWSI)).
New circuit solutions for aviation magnetic-regulated rectifying units (MRRU) are based on high-speed magnetic switches (HSMS) with magnetic cores made of advanced magnetic materials. It will allow not only to preserve in new devices all merits of their traditional solutions, such as ease of implementation and high reliability, low level of radiated emission, but also get new and improved mass and energy characteristics.
In the course of magnetic-regulated rectifying devices design it is important to notice that the HSMs are able to operate either at primary or at secondary side of power transformer.
The common features of the three-phase magnetic-regulated rectifier topologies proposed by the authors are as follows:

  • the single—wound saturable inductor is used as a magnetic switch, which compared to two—winding analog shows faster operation speed, and therefore has better dynamic properties when operating in transient modes;
  • by means of SWSI it is possible to regulate the MRRU output voltage over a wide range (from 100mV till 27V);
  • demagnetizing processes of both inductors are governed by the single control element;
  • due to narrow hysteresis curve, the dissipated energy in controlling element is relatively low;
  • current edges through the saturable inductor are relatively smoothed, and it reduces the level of radiated EMI.

For single-output onboard MRRUs the new proposed structure with SWSI at the second side of a transformer is more advantageous, because of its implementation with less number of power diodes, than in the other circuit. Therefore, it causes less power losses and provides smaller size and weight. Besides, this solution allows to connect the ground of a control system to the secondary side power ground, while in the other structure the additional local isolation is needed, which makes the structure more complex.
Carried out studies confirmed that the SWSIs, included in the secondary side of the rectifier are able to adjust the output voltage of the three-phase MRRU by means of output smoothing LC-filter. It can also ensure load short-circuit protection in emergency modes.
The stabilized magnetic-regulated rectifier, due to high reliability and low level of radiated interference, may be useful for traditional and prospective aircraft power supply systems, supplying stable DC voltage 27 V.

Keywords: regulated rectifying unit, stabilized rectifying unit, high-speed magnetic switches, single-winding saturable inductor, aircraft power supply systems, load shorting

Technical cybernetics. Information technology. Computer facilities

Yampol'skii S. M., Naumov A. I., Kichigin E. K., Rubinov V. I., Mokh M. A.

The subject of the research are developed tabular-analytical and tabular-approximating methods of altitude evaluation statistic performance calculations according to a relief height digital map.
The subject matter is the comparative evaluation of the developed relief height statistics calculations methods. Analysis of mathematical expectation and height dispersion method errors by means of tabular-approximating method is provided.
The aim goal of this is to increase the accuracy of flight altitude evaluation according to a digital height map while counting prognostic flight path by means of on-board inertial navigation systemfor flight security.
The research methodology includes the application of statistics approach for relief height calculations in lying ahead points along the aircraft flight trajectory, that should be regarded as random variables. The knowledge of the random variables distribution laws allows forming at any time t such profile of «cartographic heights», which rounding according to the aircraft control law will ensure the specified probability rates of low-flight security over the real relief.
As a result of a numerical experiment using the tabular-approximating method the following boundary values of errors are defined: the maximum error of mathematical expectation does not exceed 0,3 meters for a mathematical expectation evaluation and 0,25 meters for root-mean-square deviation of relief height evaluation.
The range of research application is the formation of the low-altitude flight informational support according to a relief height digital map by means of development of relief height array of given dimension on forward points along the aircraft flight trajectory for any time t of control signal calculation.
The research results allow recommending the tabular-approximating method for practical use during low-altitude aircraft flight echelon formation. Also it is necessary to point out the fact that the needed computing resources do not depend on planned coordinates errors during a fixed flight time.

Keywords: tabular-approximating method, relief height evaluation statistics, low-altitude flight, digital height map, on-board navigation system, method errors

Brekhov O. M., Wunna K. K.

Reducing the total time of multi-query queries processing can be achieved through co-processing of a subset of elementary queries that form an intersection of queries with multi-query. It is well known [1, 2] that the order of elementary queries processing is a significant parameter of query processing time. Here, in elaboration of our work [3] the task of forming a multi query execution plan based on the order of elementary queries processing in multiprocessor database aerospace systems is discussed.
We prove the two statements.
Statement 1. Let multi query consists of n queries which form ordered sets with successive numbers of elementary queries.
Let the conditions met:
Embedding of sets:.
Processing elementary queries from subsets   in order provides a reduction in multi-query queries multijob time.
Statement 2. Let the intersection of elementary queries sets be a subset . If a subset s is formed of elementary queries with successive numbers, starting with the first elementary query EQ1, the execution of elementary queries of subset s first off provides a multijob time reduction compared to inconsistent query execution by the time ,    where — processing time of elementary queries of subset s.
We also obtained analytical evaluation of multi-query processing time for the two patterns (geometric or arithmetic progressions) of elementary queries parameter setting in multiprocessor database when queries are defined by the following parameters:
k — the number of elementary queries that form queries of multi queries Elementary queries from d groups of u elementary queries each. Each query , consists of two groups of elementary queries with numbers: 1st group:       2nd group 
Analytical experiments have shown that

  • success probability parameter during query running isasignificant parameter affecting the selection ofeither multijob and inconsistent methods ofmulti-query processing ordetermination the number ofprocessors;
  • multijob query processing provides time inuse which isnot always minimal inrelation toinconsistent processing;
  • increasing the number ofprocessors may lead not toreduction but toincrease ofmulti-query processing time.

Keywords: database, multiprocessor computer, multi-query, distribution of elementary queries, optimization

Blagov A. V.

The paper is devoted to the study of telecommunication networks service quality by means of simulation models. Models simulating network traffic with a certain number of parameters at the same time become more and more important in practice due to increased service quality requirements for telecommunication networks. Self-similar network traffic analysis tasks become relevant for its implementation for modeling telecommunication networks during design stage. The paper considers modified telecommunication traffic models «Input M/G/∞» and «On-Off Sources» created by the author. These models allow simulation of self-similar traffic with preset properties and at the same time with predetermined statistical characteristics of small orders. A method is suggested to design and analyze two-dimensional queue distribution in given queueing system where traffic data serves as an input stream. The method is tested with developed modified models of telecommunications traffic: «Input M/G/∞» and «On-Off Sources».
The advantage of the developed model modifications «Input M/G/∞» over the base model has been proved for TCP traffic data. The advantage of developed model «Input M/G/∞» was proved in the course of local pathways simulation. Thus, a confirmation of considered developed models estimation results based on statistic performances analysis? such as the Hurst parameter, mathematical expectation, ACF and univariate distribution was obtained.
Such an approach to two-dimensional queue distribution in given queueing system can be implemented to examine one of the network service quality parameters — delay variation (jitter). Jitter examination and prediction is an important task for telecommunication systems. The obtained results can be used for simulation to analyze the amount of traffic in telecommunication networks in the course of design, as well as during developing methods for bandwidth allocation and reduction of losses in data bursts, for billing systems and other cases where service quality is important.

Keywords: self-similar traffic, traffic simulation, Input M/G/, On-Off Sources, delay variation, queuing system

Radio engineering. Electronics. Telecommunication systems

Gadzhiev E. V.

The purpose of this paper is to show the advantage of microstrip patch designed by printing technology in solving the problem of design small-sized, low-profile on-board antenna systems for small spacecrafts consisting in the fact that these antennas have a low mass, volume, cost of the production, simplicity of construction etc. For practical application, this type of antenna was proposed to design for a new antenna system of small spacecraft «Ionosphere» included in space complex «Ionosonde» created by JSC «Corporation VNIIEM» commissioned by the Russian Federal Space Agency.
The models of UHF-band and VHF-band on-board microstrip patch antennas developed using computer-aided design Agilent Electromagnetic Professional are presented. The models parameters of the primary interest such as voltage standing-wave ratio, radiation pattern, and antenna gain were evaluated and optimized during the numerical simulation to satisfy the requirements of technical specifications for antenna system of small spacecraft «Ionosphere».

Keywords: spacecraft, antenna–feeder device, on-board antenna, printing technologies, helix (spiral) antenna, microstrip patch antenna, radiation pattern. voltage standing wave ratio, gain

Isakov M. V., Nuzhdin V. M., Sokolov P. V., Usachev V. A., Schneider V. B.

The topical issue of ultra-short pulse (USP) technology is introduce in the short-range radar, which should provide the performance of low-sized object detection against background reflections from the water surface with different excitement and grazing angles of vision. The paper reveals the measured reflection characteristics from water surface by using USP probing signal (PS) in radar systems for development and analysis of algorithm effectiveness.
The proposed solution is based on analysis of the experimental studies of USP radar at grazing angles of vision over the water of varying degrees of excitement. The experimental registration of digital arrays of radar images (RI) of water surface by using USP PS was realized. The data was obtained for the pulse duration being changed from 10 ns to 100 ns with the step equal to 20 ns.
The dependence of the estimate of radar cross section from the duration of PS at various azimuth vision angles of waves was obtained. Unknown property of USP radar technology consisting in providing the detection characteristics in inter-noise areas was revealed as it performs similar to free space in the immediate presence of the underlying water surface.

Keywords: short range radar station, ultra-short pulse, outgoing signal, reflections from water surface

Material authority

Belousova E. S., Lynkov L. M.

Abstract
Spectral and polarization properties of masking materials, which have similar properties as natural background has. These materials are used for hiding ground objects from detection by remote sensing on the background surface (soil, sand, vegetation)
Purpose
This paper shows the influence of the environment in the annealing gas camera on spectral and polarization properties of shungite, which is a powdered material with grain size less than 20 microns. The samples of shungite were thermally annealed for 2 hours in different environments: the oxidized condition, condition with the addition ammonium chloride, and vacuum.
Methodology
The goniometer equipment and the spectroradiometer PSR-02 were used for investigation of spectral and polarization properties of powdered shungite after annealing in the visible and near-infrared wavelengths range (450... 2300 nm).
Findings
Shungite annealed in oxidized environment has the biggest value of spectral brightness coefficient, because there is the highest content of silicon oxide in the composition of matter. It has the smallest value of the polarization degree (0.08... 0.091). Annealed shungite in the environment with the addition ammonium chloride has the smallest value of the polarization degree too (0.06... 0.087). Values of spectral brightness coefficient of the annealed powders shungite correlate with the values of spectral brightness coefficient of vegetation. Samples of shungite annealed in an oxidized environment and in vacuum have the same values of spectral brightness coefficient as podzolized and loamy soils in the wavelength range 400-700 nm. Spectral properties of shungite annealed in environment with the addition ammonium chloride and spectral properties of black and sandy loam soils are the similar. Annealed shungite can be used as carbon materials for hiding or emphasizing the texture of materials on natural background.

Keywords: remote detection of objects, shungite, annealing, spectral brightness coefficient, polarization degree

Economics and management

Chernykh N. A.

There are favourable conditions for mutual latent crediting both for customer and supplier in commercial contracts, which include chain of mutual payments and procurements. This circumstance is caused by the fact, that the schedule and amounts of mutual settlement of accounts may bring benefit for one of the contract sides which consists in free credit resources obtained from the partner.
Current backlog of supplier shouldn’t exceed level or «regulatory value of accounts receivable» usually fixed by the customer, and in the issue of comparison accumulated advances with costs of production delivered the benefit is available for one of the contract sides, which is more efficient in payment and delivery schedule.
Thus, in large contracts for series of gas-turbine units procurement, which include attraction of bank credit, current balance of mutual settlement of accounts may come to hundred millions of roubles and be paid within tens of months by means of received bank interest, which may amount to tens and hundreds millions of roubles.
The problems of latent mutual crediting of the commercial contract sides are considered: 1) normalization the rate of the accounts receivable which should be paid by parties to a treaty; 2) normalization the sum of bridging financial gaps within the contract and assessment financial losses resulted by mutual crediting by customer and supplier, i.e. interest on their credits.
The authors developed analytical models that allow to optimize the rate of customer’s accounts receivable and estimation losses for the sides of procurement contract, which defines series of advances and product stepwise delivery.
For the last case, depending upon current balance of advances and costs accumulated, the producer may spend more than 10% of the contract price for crediting customer. It occurs in real contracts, for example in contracts for procurement of high power gas-turbine technique.
The author developed model, which allows to define average fraction of procurement price in customer’s accounts receivable during period   depending upon fraction and fraction of shipping cycle according to contract conditions:

where
Model (1) allows optimizing contract conditions for the benefit of the customer.
Also the author developed model, which allows to estimate losses of producer resulted by bridging financial gaps within procurement contract (chain of contracts). The losses are defined as difference between bank interest paid and drawn by producer:


where — balance of bridging financial gaps;
— amount of bank interest for 1 day crediting (bank interest payments);
— amount of advances received exceed the costs accumulated by producer;
 — amount of costs accumulated by producer exceed customer’s advances received.

Keywords: commercial contract, analytical model, latent crediting, rate fixation of accounts receivable, financial losses, bridging financial gaps, planning conditions of the contract

Ivanisov V. Y.

The subject of this article is the features of research and advanced development and its influence on the price limit setting of the new high technology defense products. Current legislation brings the relations between the high technology defense products developer and development customer to the work and labour relations, i.e. the relations of material products manufacturing under the contract of work and labour. The key criterion to distinguish research and work and labour relations is the concept of «new knowledge». The aim and the result of defense product development is the creation of knew knowledge about a new defense products and the knowledge of previous defense products becomes initial knowledge for creation of a new defense products. At the same time all the material factors of development process and mainly their combination in the form of new defense product prototypes are only the material means for reaching the required new knowledge. Engineering perils realization fairly lead to the extension of research and development terms and raise of the expenses. In its turn the contract of work and labour doesn’t contemplate the engineering perils. The state customer signs state contract for the development with the fixed price limit in the judicial field of work and labour. Fixed development price limit set by the state customer doesn’t correspond with the real demand for funds for the development without regard to the costs of engineering and technological perils in the process of new defense product creation and without regard to the real, not expected, inflation raise of the development costs.
Thus the development price limit can’t be reliably set and therefore there is no economic reasoning for it to be fixed. Therefore the state contract for the development of science intensive defense product should be signed only with the «reference» price without fixing the development cost.

Keywords: development features, development price limit

Lebedev G. N., Dao N. T.

In this paper we continue the investigation of the multi-link control to answer the question — how resources should be allocated among the branches of a similar nature to achieve maximum production efficiency.
The statement of the problem considers management system of an enterprise, consisted, in general, of two manufacturing and two engineering branches, production demand and generate of profits model amid variable profitability. Behavioral model of i-th production branch includes multiplicative control U1. It is also assumed that the main activity of engineering branches takes place during favorable period [0.1T0 — 0.3T0] of positive profitability growth. The proposed engineering branch model, reflecting new production quality improvement X4 is given. Developed and described in [3] product demand model, featuring the fact that sales rate depends, in the first place not only upon quality given by value C1, but also upon its rate of rise with quotient С2 > C1, on condition that С1 + C2 =1.
The task of allocation of funds among several design branches with an allowance for the period of new products design as well implementation regulations of manufacturing application of new production into different production branches is solved. The assigned task is solved in this work step-by-step by means of simulation in MATLAB.
Analysis of aircraft improvement showed that the rate of quality improvement of its individual components varies, and the highest growth of some of them achieved in a short time, while improvement of others could be provided at low rate. A linear model of allocation of funds among engineering branches is obtained. According to it the part of this funds is proportional to the expected quality improvement rate in every branch. To determine the share of funds allocated in whole for design efforts the equation taking into account expected bulk aerotechnics quality improvement rate and increase in its demand rate is obtained.
For the distribution of funds between design units, a linear model (6), according to which the share of these funds is proportional to the expected rate of improvement of quality in every link;
When analyzing the activities of two production units of the enterprise it is found that maximum efficiency is achieved in a competitive environment where in the beginning the first link gradually implements some new components, and the second link is fully transferred to new products after its sales rate becomes higher than the old one.

Keywords: control, aviation technology, production, design part

Fomkina V. I., Melik-Aslanova N. O.

At the present stage research and development (R&D) is the main engine of the qualitative economic growth especially in such high-tech and intensive industries as aerospace industry.
R&D requires high level of funding due to significant financial and material costs. The value of research and development is the most important indicator when deciding on R&D funding regardless of what financing channel is used.
R&D value determination is the basis for setting the price for its execution for any possible pricing model for research and development. Even if the market-based approach to calculate the execution costs is not used, cost value estimation is still the basis for evaluating the profitability of work. The estimated cost of R&D is carried out by justifying the expected costs on different objects of expenditures and combining them into the single calculation.
Authors carried out the analysis and systematization of the existing research and development valuation techniques in various fields, approaches and methods of costing used in these techniques. The features of the various R&D valuation techniques and the major problems in this area were identified.
The main methods of R & D cost calculation that are used in the various techniques are the following: the market method (method of analysis of comparable market prices), the method of analogues cost analysis with subsequent correction, the method of estimating the execution of work or the provision of services, the method based on costing considering rate of return, the method of application of specific indicators using scaling (parametric method).
Costs classification that is used by many methods, is governed by different regulations. At the same time to detect the standards that define costs level is a task that needs justification. One of the most complex tasks that has to be solved during the R&D value determination is defining the labour-intensiveness of all the work and different stages of the work.
One of the most important directions of further development of R & D value determining system is to improve the legal and regulatory basis of this assessment, and to create the incentives for contractors to reduce costs at the required quality level of R & D.

Keywords: Research and development (R&D), aerospace industry, methods of R&D value calculation, initial (maximum) contract price, labour-intensive

Kaloshina M. N., Ermakova O. V.

At the present stage research and development (R&D) is the main engine of the qualitative economic growth especially in such high-tech and intensive industries as aerospace industry.
R&D requires high level of funding due to significant financial and material costs. The value of research and development is the most important indicator when deciding on R&D funding regardless of what financing channel is used.
R&D value determination is the basis for setting the price for its execution for any possible pricing model for research and development. Even if the market-based approach to calculate the execution costs is not used, cost value estimation is still the basis for evaluating the profitability of work. The estimated cost of R&D is carried out by justifying the expected costs on different objects of expenditures and combining them into the single calculation.
Authors carried out the analysis and systematization of the existing research and development valuation techniques in various fields, approaches and methods of costing used in these techniques. The features of the various R&D valuation techniques and the major problems in this area were identified.
The main methods of R & D cost calculation that are used in the various techniques are the following: the market method (method of analysis of comparable market prices), the method of analogues cost analysis with subsequent correction, the method of estimating the execution of work or the provision of services, the method based on costing considering rate of return, the method of application of specific indicators using scaling (parametric method).
Costs classification that is used by many methods, is governed by different regulations. At the same time to detect the standards that define costs level is a task that needs justification. One of the most complex tasks that has to be solved during the R&D value determination is defining the labour-intensiveness of all the work and different stages of the work.
One of the most important directions of further development of R & D value determining system is to improve the legal and regulatory basis of this assessment, and to create the incentives for contractors to reduce costs at the required quality level of R & D.

Keywords: Research and development (R&D), aerospace industry, methods of R&D value calculation, initial (maximum) contract price, labour-intensive

Kanevsky E. V.

The present stage of development of the enterprises of aviaengine-building it is necessary to consider the organization of productions in constant interrelation with management of deliveries of material resources and management of realization of finished goods. In the conditions of the increasing competition the success of the enterprises of aviaengine-building depends on speed of response to continuous changes in external infrastructure. The enterprises have to have the management mechanisms, allowing to carry out adaptation to market conditions and the competition in the world markets of the Russian producers of engines of aircraft. Need of formation at the enterprises developing and making engines for domestic aircraft, the organizational and economic conditions allowing these enterprises normally to function in the conditions of developed market economy moves forward.
In modern conditions of the enterprise of aviaengine-building had a real opportunity to operate the production stocks, using this opportunity to strengthen the positions in the market. The system analysis of conditions, features and transformations, characteristic for the aviaengine-building enterprises, gives the full grounds to claim that their needs for models of optimization of stocks, for goals logistic management of production efficiency will constantly amplify.
The effective functioning of the manufacturing aviaengine-building enterprises estimated, first of all, by cost of occurring processes, significantly depends on the organization of movement of material streams, and also on correctness of decisions on management of these streams. However, now the industrial enterprises have to pay special attention not only optimization of movement of material streams from the supplier to the consumer, to their intra production advance, but also resource safety of logistic management of the aviaengine-building enterprises.
Practical actions on ensuring resource safety are based on a standard and legal basis of activity of the enterprises of aviaengine-building, measures of economic incentives, methods of implementation of policy of resource safety, administrative control levers, motivation of the personnel, ensuring compliance between profitability and risk, ratio optimization «volume-expense-profit», optimization of stocks, optimization of intra production movement of material streams, modernization of park of the equipment and others. Thus, increase of resource safety of activity of the enterprises of aviaengine-building in many respects is defined by the speed and accuracy of reaction of the enterprise on arising external and internal threats where a key factor defining efficiency of logistic production management is creation of system and realization of the mechanism of ensuring resource safety of the enterprise.
It is possible to formulate the main directions of realization of measures for ensuring resource safety. It is possible to refer development of strategy and concepts of logistic management to them productions, movement of material streams; definition of methods and tools of logistic production management; development of actions for increase of resource safety of activity of the enterprises of aviaengine-building.

Keywords: resource security, logistics, production management, material flow

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