Vol 17, No 2 (2016)
- Year: 2016
- Articles: 36
- URL: https://journals.eco-vector.com/2712-8970/issue/view/7661
Articles
APPLICATION FEATURES OF NEURAL NETWORK STRUCTURES AND THEIR ELEMENTS TO INCREASE PRODUCTIVITY OF ONBOARD DIGITAL COMPUTING SYSTEMS
Abstract
The article presents the results of several generations of onboard digital computing systems produced by SPA of automatics, describes the features of applied components. It examines the basic principles of improving the accuracy of structural calculations and circuit techniques including high precision calculations at tight constraints on the scale of the data processing hardware for each generation of the basic. The redundant single-processor onboard digital computers (ODC) and the problems encountered during their implementation are considered. The article describes the first ODC architecture and how they differ from those that existed at the time of computers for general use. The author emphasizes attention to logic elements created by SPA of automatics for digital blocks. The structure of the redundant ODC is analyzed. The problems associated with the choice of the structure are described. The authors list the changes in the architecture of ODC that occurred in the second generation. The authors examine “Malakhit” family ODC which implements the principle of modular construction systems, their architectural and structural differences from the ODC of the past generation. These differences cause the superiority of “Malakhit” ODC parameters as power consumption, weight, dimensions, performance and informative capacity. The authors refer to Malakhit-2 ODC as an attempt to create a high-speed system. The article describes magistral and modular onboard digital computer system (ODCS), the purpose and principle of their interaction module. The authors offer the application of a matrix neural calculator for solving the transformation of coordinate systems. The principles of its operation and the resulting gain in speed of solving the problem are examined. The authors touche upon the issue of the transition from large-scale integrated circuits with software control to the extra-large integrated circuits (VLSI), implementing neural network computation, and the creation of a new generation of Malakhit -7 ODC. The basic directions for further work on the creation of computer systems are stated. The authors consider such promising areas as the creation of distributed systems and the creation of on-chip system in the form of VLSI. In conclusion, it is noted that the use of neural network structures can be seen as one way to significantly improve the performance of digital computer systems.
Siberian Aerospace Journal. 2016;17(2):276-288
276-288
MAGNITOELECTRICAL PROPERTIES OF NdxBi1-xFeO3 MULTIFERROICS
Abstract
On (Bi0.9Nd0.1)FeO3 films deposited on a glass substrate with ~ 160 nm thickness in a 100 Hz < ω < 105 Hz frequency range and the temperature range of 300 K < T < 450 K are carried out studies of permittivity and dielectric loss tangent without magnetic field and in the magnetic field with induction of B = 0.8 Tesla. It was found that magnetocapacitance of the (Bi0.9Nd0.1)FeO3 film has the same value as for bulk samples. The presence of the neodymium in the (Bi0.9Nd0.1)FeO3 films increases magnetocapacitance value at room temperature in comparison with BiFeO3. In the conditions of magnetic field absence a film permittivity has an anomaly at T = 394 K and magnetocapacitance (ε(Н) - ε(0))/ ε(0) reduces in several times. Using the results of the temperature dependences of the specific magnetization study are determined the values of the (Bi0.9Nd0.1)FeO3 films magnetic moment in a wide temperatures range. It was found that in the temperature range of ~ 80-1000 K the magnitude of the magnetic moment of the (Bi0.9Nd0.1)FeO3 films decreases from the value of μ = 1.11 μВ to μ = 0.24 μВ. In the 370-400 K temperature range, where we have a magnetocapacitance minimum and a sharp decreasing of the dielectric loss in the magnetic field, the magnetic moment of studied films has a value μ ≈ 0.9 μВ = const. The reduction of the magnetic moment value of the (Bi0.9Nd0.1)FeO3 film up to μ ≈ 0.35 μВ and output to the plateau at T ~600 K is most likely due by the magnetic phase transition peculiar to BiFeO3 near this temperature.
Siberian Aerospace Journal. 2016;17(2):289-295
289-295
EVALUATION OF EFFECTIVENESS OF HIGH PERFORMANCE COMPUTING SYSTEM WITH FUNCTIONAL MODELS
Abstract
Educational institutions, organizations and companies operating in knowledge-intensive industries, are often in need to make conducting intensive calculations using the high-performance supercomputing systems and computer networks. As the algorithms of distribution of tasks within such systems, people use standard algorithms aimed at efficient operation with a lot of similar tasks. At the meantime, there is a whole class of problems, which requires the successful completion of a number of conditions, such as having certain problem-oriented software, specific requirements for hardware resources of compute nodes, and others. This class of tasks also includes the tasks associated with the calculation of the path of movement of the planets, geological exploration, big-data analysis, etc. In this case, for the successful distribution of the load within a high-performance system we use special algorithms for planning and allocation of tasks. So, effective usage of computing resources in case of high-performance computing centers is the actual problem. The main aspect of this problem is the approach of task planning and distribution across computing nodes. This article covers the main algorithms of huge tasks distribution in large computing systems, such as First Come First Served, Shortest/Longest Job First, Backfilling, Round-robin, etc. To evaluate the effectiveness of these algorithms the authors have developed a model of a computer system, showing the structure of an existing computer system of SFU. As the initial experimental data authors used a variety of tasks which have run in the computing system of SFU over the past few years. As a platform to simulate running tasks SimGrid platform and Alea were used. The closest to the real conditions were achieved for the evaluation of the effectiveness of different algorithms of distribution of user tasks. Using the experiments results, the authors propose some solutions for the modernization of the existing computing infrastructure.
Siberian Aerospace Journal. 2016;17(2):295-301
295-301
NEURODYNAMIC HEALTH DIAGNOSIS BEFORE, DURING AND FOLLOWING SPACE FLIGHTS
Abstract
The urgency is based on need developing algorithms for detecting health state of an astronaut. The main aim of the study lies in developing neural network model for breathing that will allow recognition of breath patterns and predicting anomalies that may occur. Class of machine learning algorithms includes many models, widespread feed forward networks are able to solve task of classification, but are not quite suitable for processing time-series data. The paper describes results of teaching and testing several types of dynamic or recurrent networks: NARX, Elman, distributed and focused time delay. The methods used in the study include machine learning algorithms, dynamic neural network architectures, focused time-delay network, distributed time-delay network, non-linear autoregressive exogenous model. Networks were built using Matlab Neural Network Toolbox 2014a software. For the purpose of research we used dataset that contained 39 polysomnographic recording. Records were obtained by pulmonology department of Third Tomsk City Hospital; on average recording were 8-10 hours long and included electrocardiography and oronasal airflow. Frequency of these signals was 11 Hz. The results include comparison of training and testing performances for various types of dynamic neural networks. According to classification accuracy obtained for learning and testing set of data, the most accurate results were achieved by non-linear autoregressive exogenous model.
Siberian Aerospace Journal. 2016;17(2):302-308
302-308
NUMERICAL ALGORITHM FOR OPTIMIZATION OF A PROCESS OF CONICAL FLYING MODEL EQUILIBRATION ON A VERTICAL BALANCING STAND
Abstract
High complexity and cost of developing flying models necessitate the use of such design and production techniques that would ensure the best flight technical and technological characteristics of the model also would rise of its operation effectiveness. These techniques include the experimental control method of flying model’s mass-inertia asymmetry parameters during final assembly of the model. The problem of process optimization in bringing parameters of mass-inertia asymmetry of the conical flying model to specified standards is set and solved for the process of balancing in dynamic mode in the article. The model as a component of prefabricated rotor is being balanced on a low-frequency dynamic vertical stand on gas bearings. As a criterion of optimization the minimum center-mass shift from geometrical axis of the model is taken at simultaneous maintaining the pre-set standard for the angle of deviation of principal longitudinal centroidal axis of inertia relative to the above axis. The work relies on engineering model, developed from refined mathematical model of balancing the conical body of rotation, which the only correction plane is designed to be positioned close to cone face, away from the center mass of the body. This engineering model describes all stages of the process of bringing mass-inertia asymmetry parameters to the values not exceeding specified limiting values. Before balancing experiment the weigh, longitudinal center of mass and inertia moments of the flying model have to be controlled with use of measurement equipment. Balancing algorithm, easy-to-realized by modern computers, was analyzed. Numerical illustration of balancing is given. The engineering model enables omitting intermediate steps of balancing, reducing them to one step (as a rule), and shortening the balancing time, as well. In one step of balancing the engineering model permits either bringing parameters of mass-inertia asymmetry of the flying model to specified standards, or diagnosing impossibility of attaining the specified standards with available design of flying model. Application of methods and instruments of dynamic balancing allows increasing accuracy in both defining and assuring requirements for the parameters of mass-inertia asymmetry as compared with equipment based on methods of static balancing, and, hence increasing efficiency of flying models operation. Design algorithm and balancing method are experimentally tested at newly-designed vertical dynamic stand on conical gas bearings.
Siberian Aerospace Journal. 2016;17(2):309-317
309-317
ON THE ERRORS OF ISOTROPIC APPROXIMATION TO THE GEOMETRIC-OPTICS DESCRIPTION OF IONOSPHERIC RADIO WAVE PROPAGATION
Abstract
A geometric optics approach is of vital importance when considering high frequency radio wave propagation and space weather effects. Isotropic approximation, i. e. neglect the effect of the Earth’s magnetic field, is widely used to simplify the ray-optical description of ionospheric propagation of radio waves. In particular, the advantage of this approach is that for a set of ionospheric models it allows to obtain analytical solutions for the parameters of the ray path. It has been extensively discussed in the literature that the isotropic approximation works quite well for oblique ionospheric sounding being representative of the ordinary mode. Thus, it has been established that with increasing the launch angle (i. e. for more oblique paths), the isotropic approximation error decreases, in fact not being able to distinguish between isotropic and anisotropic media for paths of the order of thousand kilometers long. The efficiency of the approximation is of vital importance for applications where simplification of the software implementation and reduction of the calculation execution time is required. However, this description under certain conditions may produce a significant error. In particular, it is not applicable for vertical and near-vertical sounding in the cases where operating frequency is close to critical frequencies of E and F2 layers. Two-dimensional ray tracing scheme is applied to the initial value problem and to the boundary value problem. The refractive index of the ionosphere is given by the Appleton-Hartree formula (ignoring collisions). Thus, the purpose of the study is to examine the no-field approximation error under different conditions of radio wave propagation on the basis of ray tracing analysis.
Siberian Aerospace Journal. 2016;17(2):318-323
318-323
AUTOMORPHISMS OF NIL-TRIANGULAR SUBRINGS IN CHEVALLEY ALGEBRA OF ORTHOGONAL TYPE
Abstract
Any Chevalley algebra over an associative commutative ring K with the identity is characterized by Chevalley base that correspondents to each indecomposable root system Ф. All elements er (r Ф+ ) of Chevalley base give a base of subalgebra NФ(K) which is said to be nil-triangular. Automorphisms of algebras NФ(K) were described by Y. Cao, D. Jiang and D. Wang (J. Algebra, 2007) at K = 2K for Lie type Bn, Cn or F4 and under similar restrictions for other types. Their description uses only non-standard Gibbs’s automorphisms; in our terminology it is a hypercentral automorphisms of height 2 or 3 (for type Cn). Our main purpose is to describe the automorphism group A of the Lie ring NФ(K). The algebra NФ(K) of Lie type An-1 can be represented as Lie algebra which associated to the algebra NT(n, K) of all nil-triangular matrices over K. The automorphism group of the ring NT(n, K) and of its associated Lie ring (i. e., A for the type An) described earlier V. M. Levchuk (1983). A. V. Litavrin has described the automorphism group A for Lie type Cn recently. In the present paper we find non-standard automorphisms of the algebra NФ(K) for orthogonal types, when the condition K = 2K isn’t satisfied. It seems that if annihilator of element 2 in K is non-zero, then the largest height of hypercentral automorphisms grows together with the Lie rank. Also, we find automorphisms of the algebra NФ(K) of type Dn which are non-standard module second member of lower central series and generate the subgroup of A that isomorphic to certain subgroup S in SL(2, K); in particularly, S = SL(2, K) at 2K = 0. The standard automorphisms together with constructed non-standard automorphisms generate every automorphisms of the algebra NФ(K). For all classical types of rank > 4 our results show that the automorphism group A is the product of subgroups of the central and induced ring automorphisms and the automorphism group of the algebra NФ(K). We use developed earlier methods, in particularly, a special representation of the algebras NФ(K) of classical types. The results can be used in development of cryptographic methods.
Siberian Aerospace Journal. 2016;17(2):324-327
324-327
RESEARCH OF THE RETRIAL QUEUEING SYSTEM | |1 WITH R-PERSISTENT EXCLUSION OF ALTERNATIVE CUSTOMERS
Abstract
Рассматривается космическая сеть связи, управляемая протоколом случайного множественного доступа. Построена математическая модель двух фирм, конкурирующих за право обладания сетевым ресурсом. Каждая фирма пытается продвинуть свои сообщения в широковещательный канал связи, вытесняя сообщения альтернативной фирмы. Данная модель может использоваться для передачи срочных сообщений, задавая приоритет той или иной фирме. Математической моделью конкурирующих фирм является RQ-система с двумя входящими простейшими потоками, произвольным распределением времени обслуживания и вытеснением альтернативных заявок, т. е. если в момент прихода заявка первого типа обнаруживает прибор занятым заявкой первого типа, то она уходит в ИПВ1 (источник повторных вызовов для заявок первого типа), где осуществляет случайную задержку, распределенную по экспоненциальному закону с параметром s1. После случайной задержки заявка вновь обращается к прибору с повторной попыткой его захвата. Если же в момент прихода заявка первого типа обнаруживает прибор занятым заявкой второго типа, то пришедшая заявка с вероятностью r1 вытесняет заявку второго типа, которая уходит в ИПВ2 (источник повторных вызовов для заявок второго типа), а сама встает на обслуживание, иначе с вероятностью 1 - r1 уходит в ИПВ1, где осуществляет случайную задержку. Для заявок второго типа ситуация будет аналогичная. Исследование системы проводится методом асимптотического анализа в предельном условии большой задержки заявок в ИПВ. При использовании данного метода составлена система дифференциальных уравнений Колмогорова для распределения вероятностей числа заявок в источниках повторных вызовов и состояний прибора, выполнен переход к системе дифференциальных уравнений для частичных характеристических функций. Применяя предлагаемый метод для данной RQ-системы, получены среднее значение числа заявок в первом и втором источниках повторных вызовов и распределение вероятностей состояний прибора. Рассмотрен пример численной реализации для функции распределения времени обслуживания, представляющей взвешенную сумму гамма- и экспоненциального распределений. Установлено, что для некоторых значений параметров распределения времени обслуживания и интенсивности входящего потока стационарный режим в системе не существует, а для некоторых других значений параметров распределения времени обслуживания стационарный режим существует при любых сколь угодно больших значениях интенсивностей λ1 и λ2 входящего потока. Результаты могут быть использованы для установления количества сообщений, которые ожидают повторного обращения, а также для установления значений параметров, при которых система работает оптимально.
Siberian Aerospace Journal. 2016;17(2):328-334
328-334
COMBINING CLUSTERING AND CLASSIFICATION APPROACHES FOR SPEECH-BASED EMOTION RECOGNITION PROBLEM
Abstract
Communication is an important ability of a human, which is based on linguistics and the emotional component. In the field of technology, the emotion recognition is still a challenge, especially when the recognition is based solely on the voice, which is the primary means of human communication. Selecting of relevant features for automatic classification and recognition is an important step. Recognition efficiency of speaker’s emotions depends on the database used in the system. Recognition of speaker’s emotions is a difficult task, since it requires a set of consecutive operations, such as voice activity identification, feature extraction, training and classification. Speech-based emotion recognition is one of the most popular and common task in the field of the computer linguistics. In this area, the main criterion is the accuracy of the classification procedures. In current work, a variety of data mining techniques, such as artificial neural networks, logistic regression, support vector machines, are proposed to solve the problem of automatic emotion recognition. To improve the performance of emotion recognition we used pre-clustering and classification approaches. The method of principal component analysis is used for selecting important features. Testing of the proposed approach was carried out with the task of emotion recognition based on acoustic characteristics.
Siberian Aerospace Journal. 2016;17(2):335-342
335-342
THERMAL-STRUCTURAL ANALYSIS PROCEDURE OF LARGE MESH REFLECTOR FOR SPACE APPLICATION
Abstract
The accuracy of geometrical and surface properties of space antenna reflectors have to meet a set of strict requirements that makes the need of evaluation of thermal deformation influence on reflecting surface shape distortions during development of the new structure. Thermal distortion analysis of large antenna reflectors that operate in orbital environment conditions is cross-disciplinary complex problem. In article the procedure of integrated thermal-structural analysis of large membrane structures is presented. Modern software based on the finite element method is applicable for performing the analysis using this procedure. The goal of this procedure is to predict thermomechanical behavior of the reflector structure under transient on-orbit heating load. Analyzing using this procedure allows tracking the evolution of thermal distortion during orbital flight and getting necessary information on geometrical stability of the reflecting surface form. The initial data for performing the analysis are spacecraft geometric model and orbital data. The procedure considers determination of initial prestressed structure configuration. Thermal and structural analyses performed using two different finite element model based on different components of the spacecraft system. According with the procedure, view factor calculations should be made with the thermal model using Monte Carlo method. Using the procedure presented in the article thermomechanical analysis was performed and form accuracy of the reflecting surface of large reflector as a part of spacecraft on the geostationary Earth orbit was estimated. Thermal-structural analysis considered two different of solar declination: March equinox and December solstice as extreme simulation cases for this orbit. To perform a numerical simulation NX and ANSYS are used. The algorithm of direct temperature translation between the nodes of different models is presented. Using the performed analysis results geometrical properties changes of the disturbed parabolic surface were estimated.
Siberian Aerospace Journal. 2016;17(2):343-358
343-358
APPLICATION OF SENSITIVE FUNCTIONS, WHICH USED TO COMPUTE TUBES INCLUDING THE TRAJECTORIES OF CONTROL SYSTEMS
Abstract
This article presented the use of sensitivity functions to compute the boundaries of inclusions of control systems reachability sets and their application to problems of estimation tolerances of aircraft motion, or missiles motion, or spacecraft motion. As a rule, the model of the control system is carried out throughout the range of the defining set of parameters in the framework of the sensitivity of numerical investigation of the parametric. The practical application of this approach is very often impractical or impossible because of the huge number of required computations and countless of the results. The combined use of the sensitivity functions and the analytical formulas of solutions proposed and implemented in the article, can effectively compute the inclusion of reachable sets. These sets include all trajectories of the control system, starting at the initial time point in the initial set. The inclusion of reachable sets are used in problems of guaranteed estimation of variance sets aircraft and in problems of control tolerances, considering that the current external disturbances of system and errors of observation are enclosed within certain limits (constrained by limitations). Defined sensitivity functions are derivatives of various state variables with respect the parameters of the appropriate group. Obtained these functions are solutions of the sensitivity equations constructed directly from a known parametric model of the system. Using the method, based on symbolical formulas for the solution and based on sensitivity function, allows getting a reliable estimate of reachable sets of control systems in conditions of uncertainty. Control actions are included on the right side of these systems arbitrarily, not only as an additive term. Application of this method involves the problem of estimating the maximum deviations of the aircraft motion at the stage of the automatic approach, the problem of determining the possibility of loss of stability of the aircraft motion at a given time, that is the problem of safety of the aircraft trajectory, the problem of the helicopter landing. Simplified criteria for buckling in such problems are the computation of a threshold or critical value of one of the motion parameters, and evaluation of the boundaries of all possible trajectories. The article presents the results of numerical methods based on the use of analytical formulas and sensitivity functions and evaluating all its possible values (reachable sets of control systems).
Siberian Aerospace Journal. 2016;17(2):350-358
350-358
CALCULATING LATERAL DEFLECTION OF PLATES SUBJECTED TO HETEROGENEOUS FORCES OF INERTIA USING A VARIATION-DIFFERENCE METHOD
Abstract
The deformation of plates is reduced to the generalized problem of eigenvalues based on the stability criterion, which establishes equilibrium in the mechanical system. A method for calculating stability for thin plates under inertia loads exerting force on the basal plane is proposed. Having a differential formulation of the problem, the matrices are formed. The first is a stiffness matrix: it is based on Marie-Sophie Germain’s biharmonic equation. The second matrix represents the change of internal stresses or internal forces in the plate. The stiffness matrix is always symmetric and positive definite for the fixed plate. The matrix of the internal forces in the approximation of derivatives of functions under central differences, from the action of inertial forces can be asymmetric with respect to the main diagonal, can also degenerate and rows of this matrix is the feature of inertia loads. The finite difference method allows us to form a system of large dimensional equations. However, difficulties may arise at the free edges and corners of the plate, which complicates the calculation procedure. Therefore, a transition from the differential formulation of the problem to an integral formulation discretization with variational-difference method is performed. In this case a second row of nodes is not formed during the formation of the stiffness matrix at the free edge. The matrix of the internal forces is always symmetric; it can be ill-conditioned, however, this factor does not affect the problem of determining eigenvalues. Scientific literature provides many theoretical studies and solutions to practical tasks of calculating the stability of structures, including the calculation of longitudinal-transverse bending of thin plates. However, this is a task that has positively certain operators. We have conducted a research of the application of the variational-difference method for calculating the stability of structures. The differential formulation of the boundary value problem is transformed into a variational formulation; the stability criterion is solved; the issue of approximating differential operators for discrete problems with a finite number of variables is addressed in the paper. The paper also describes a developed set of algorithms for the Maple mathematical system and a compilation of calculating programs. Examples of the calculation are considered. We have studied a plate that is rigidly secured at one side while the other three sides are left unfixed. Values of the critical accelerations have been obtained. Problems are assigned to the generalized problem of eigenvalues in which the acceleration parameter, such as the parameter of load, is the only unknown property. Paper objective: the development of a method for calculating inertia loads on plates.
Siberian Aerospace Journal. 2016;17(2):359-367
359-367
IMPROVING OF ESTIMATE OF THE NUMBER OF 6-APERIODIC WORDS OF FIXED LENGTH
Abstract
W. Burnside raised the issue of locally finiteness of groups, all elements of which have finite order. A negative answer was received only in 1964 by E. S. Golod. Later S. V. Aleshin, R. I. Hryhorczuk, V. I. Sushchanskii proposed series of negative examples. Finiteness of the free Burnside group of period n installed at different times for n = 2, n = 3 (W. Burnside), n = 4 (W. Burnside, I. N. Sanov), n = 6 (M. Hall). Proof of infinity of this group for odd n ≥ 4381 was given by P. S. Novikov and S. I. Adian (1967), and for odd n ≥ 665 in the book of S. I. Adian (1975). More intuitive version of the proof for odd n > 1010 was proposed by A. Yu. Olshansky (1989). In connection with these results we consider sets of aperiodic words. Under the l-aperiodic word understand the word X if in it there is no non-empty subwords of the form Yl. We consider the question about the number of 2-aperiodic words in a two-letter alphabet and how many 3-aperiodic words in this alphabet. In the monograph of S. I. Adian (1975) shows a proof of S. E. Arshon (1937) of the fact that in the two letters alphabet there is an infinite set of arbitrarily long 3-aperiodic words. In the book of A. Yu. Olshansky (1989) a theorem on the infinity of the set of 6-aperiodic words and obtained a lower bound function for the number of words of a given length was proved. Our aim is to get more accurate estimate for the function of the number of 6-aperiodic words of given length . The results can be applied when encoding information is used in space communications.
Siberian Aerospace Journal. 2016;17(2):368-371
368-371
GEOMETRICAL AND FINITE-ELEMENT MODELING OF LATTICE CONICAL SHELL WITH GEODESIC PATH OF SPIRAL RIBS
Abstract
Cylindrical and conical lattice shells are used in the space industry as the parts of stages of launch vehicles, load-bearing spacecraft constructions and payload adapters serving for connection with spacecraft launch vehicles. Conical shells, currently used in JSC “Information satellite systems” named after academician M. F. Reshetnev”, are designed and manufactured by an automatic winding with paths of the spiral ribs oriented along the geodesic lines. Such lines are the straight lines on the involute of surface of the cone. This article discusses distinguishing features of geometrical and finite-element modeling of lattice conic shells with geodesic path of spiral ribs, which are used by payload adapters for spacecraft launchers. The algorithm of calculation of coordinates of points of an elementary segment of a lattice conic shell is described. The elementary segment represents a set of the pieces connected among each other. The task about creation of geometrical model of an elementary segment is reduced to determination of coordinates of points of the beginning and end of each piece of a segment in the set system of coordinates depending on the key design parameters of a lattice conical shell. The algorithm of calculation of these coordinates is received as a result of the analysis of the involute of surface of a lattice conical shell. Realization of this algorithm in the built-in programming language of any CAE-system allows building in the automatic mode geometrical model of an elementary segment of a lattice conical shell for her subsequent splitting into finite elements. The offered algorithm will allow considerably simplifying and accelerating the process of the analysis of the lattice conical shell by means of software.
Siberian Aerospace Journal. 2016;17(2):372-376
372-376
DESIGN OF THE LARGE-SIZE HIGH-PRECISION REFLECTOR OF THE SPACECRAFT ANTENNA WITH THE PLANIMETRIC DIRECTIONAL DIAGRAM
Abstract
Exploration of high frequency range of onboard antenna system and growing of SC on-board repeater power allow receiving and transmitting lots of information data and organizing high quality channels of fixed satellite communication. A reflector is a key antenna element. Pointing accuracy depends on precision and dimension stability of reflector, subjected during operation to the influence of such negative factors as extreme positive and negative temperatures (taking into account their gradient), vacuum and radiation. Also, the increasing of spacecraft capacity and gain ratio in given coverage area can be provided by increasing of reflector aperture area with specially graded reflecting surface, forming contoured antenna pattern. Strict requirements to the shape precision of the reflecting surface of the reflector and strict antenna weight restrictions suggest the usage of structural material, having extremely low thermal expansion ratio, high specific strength and stiffness properties, low density, resistance to continuous static and dynamic loads, vibration resistance, operation feasibility under high and low temperature conditions. The results of a new large-size offset SC antenna reflector design, forming contoured antenna pattern, made of composite materials are presented in the paper. The structure is realized according to the “superlight” reflector scheme and consists of two main elements: reflector and primary structure. It allowed decreasing reflector mass by 30 % in comparison to standard construction. Moreover, the given reflector has temperature and mechanical decoupling of structural components. The paper includes complex algorithm of the large-sized antenna reflector design. The rationale is presented relating to the choice of design-layout scheme and used materials. The problem of determining reflector locking device positions on the SC according to vibration frequency value is solved. Mechanical analysis and optimization of design parameters of reflector construction are carried out. The results can be interesting to wide range of specialists: to design engineers, engineers and material engineers.
Siberian Aerospace Journal. 2016;17(2):378-387
378-387
INCREASE OF EFFICIENCY OF AIRCRAFT MONITORING BY MEANS OF APPLYING INTEGRATED DETECTION SYSTEM
Abstract
Transition to more global systems of air navigation is caused by the restrictions imposed by ground facilities of location determination. Limitation in territorial application of ground facilities and appearing errors at determination of coordinates of object because of repeated reflection of radio waves became the reason of transition. Creation of navigation satellite systems GPS and GLONASS has turned out to be consequence of attempts to make the global radio navigational field available on all square of the globe. To solve a similar task with applying land complexes is difficult as the costs of placement and service will become inadmissible high. GLONASS and GPS systems have the minimum error of determination of location in the territory of the Russian Federation only when cooperate using. For civil needs at GPS satellites the channel has been allocated in which the error of determination of coordinates is intentionally increased. In GLONASS system inaccuracy is caused by natural sources of errors; however the degree of a covering complicates use signals only of these satellites. The task at the minimum changes in the onboard equipment of the aircraft to increase efficiency of its monitoring from the earth was set. The authors offer to use the group of low-orbital Iridium satellites for data transmission about location of the aircraft on the control office located on the earth. Data transmission is possible with the use of GSM communication through land stations, and by means of inter-satellite communication lines. The communication satellites Iridium have full coverage of a terrestrial surface that makes possible to carry out monitoring of aircrafts in remote areas. In the Russian Federation those are subpolar areas. The authors of the paper developed the scheme of monitoring in which the terminal programmed device the UTP type is placed onboard, accepting signals of satellites of navigation and via communication satellites transferring data on location of object to control office. Control office provides the analysis of the received coordinates and creation of a trajectory of flight of object.
Siberian Aerospace Journal. 2016;17(2):388-392
388-392
DYNAMICS OF AUTOMATED ELECTRIC DRIVES WITH COMBINED OPTIMAL CONTROL SYSTEM
Abstract
Optimum control systems of technical systems, widely used in the space industry, have been further developed in the theory of optimal combined control systems, which are built with consistent correction of internal coordinates, which reduces the order of the object equations systems management and regulation of foreign origin on the basis of optimal control theory, the theory of variable structure systems or multiply automatic control systems. The article considers the automated electric drive mining equipment by the example of the excavator, the duty cycle of which is associated with severe service conditions: high dustiness, re-intermittent operation, shock, vibration, high frequency switching, varying over a wide range of load on the motor shaft, which affects both the quality and quantity of rock production volumes, and the state mining machinery systems in general. The electric rotating mechanism, having the largest number of failures in mechanical and electrical parts of excavator, combined with optimal control system representing the inner loop voltage and analytically constructed optimal controller (ACOC) current anchor chain and the speed of the motor, located in the direct channel control system, has been considered. To investigate the drive simulation model has been created in the program MATLAB Simulink package. Changing the coefficient of feedback on the motor current and the speed of the first mass effect on the transition process and on the rolls elastic torque automated electric excavator turning. With an increase in the weighting of the feedback factor on the motor current increases during the transition process and reduces the time of the elastic rolls, increasing the weight of the feedback factor for the first mass velocity decreases during the transition process and increases the moment of the elastic rolls. The effect of weighting coefficients optimality criterion on the dynamics of the drive is in Run Mode, and an algorithm for selecting the weighting factors. The results showed the advantage of optimal combined rotation drive control system of the excavator in comparison with the classical system of slave control.
Siberian Aerospace Journal. 2016;17(2):393-401
393-401
APPLICATION OF THE METHOD OF LOAD TESTING WITH GROUND experimental METHOD of CONTROL UNITS OF antenna GUIDANCE system
Abstract
The key element of modern spacecrafts is high-precision antennas. Therefore the antenna guidance system (AGS) is present practically on any spacecraft (SC). Great demand is placed on AGS on each SC. Ground experimental method of antenna guidance system includes a set of stages and types of testing, but it isn't always enough of them for identification of short-term failures. Modern control modules of antenna guidance system (AGS CM) have various variants of construction. The option of AGS CM creation used on SC with active lifetime more than 15 years is considered in the article. With the offered option of the device creation as ground experimental method showed, short-term failure of command transmission is possible. For identification of such single failures the method of load testing which is usually used when testing the software of client-server applications and complicated IT- systems was used. The special test software was developed for probe of the device, and also imitating program model of angle conversion block. This development allowed revealing single failures when commands transmitting for change of speed of rotation of the antenna on the MIL-STD 1553B interface, and also to check and confirm possibility of rejecting such failure. Such method of testing can be applied during tests and probes of any components of SC in which data transmission through the MIL-STD 1553B interface is used.
Siberian Aerospace Journal. 2016;17(2):402-407
402-407
LARGE TRANSFORMABLE PRECISION ANTENNA BASED ON SOLID REFLECTING PANELS
Abstract
Development of modern information space communications systems is moving towards the development of high-frequency bands. This is mainly due to the need to organize high-speed data transmission channels. To successfully solve these problems antenna systems with precision reflectors transformable large aperture are used. Convertible configuration of the reflector determines the requirements for the placement of the antenna under the fairing of the launch vehicle. Accuracy reflecting reflector surface profile is associated with the operation of the antenna in high frequency bands. The necessary accuracy of the reflector can be achieved by a rigid solid panel by using as a reflecting surface. A search was conducted of such antennas in existence today. It showed that the existing concepts have several design flaws. The paper presents the design of large-size precision antenna on the basis of solid-state reflective panels, which has several advantages over its peers. The main advantages are reliability and high rate of transformation. High reliability is achieved through the use of a small number of mechanical components and the use of a fundamentally new antenna deployment scheme allows obtaining a high rate of transformation. Accuracy of the reflecting surface of the reflector is one of the basic parameters and depends on the stiffness of the structure as a whole. The proposed design of the power circuit can provide sufficient rigidity at a relatively low weight of the antenna. As part of the work carried out modal analysis developed design and parametric model is obtained, which can be used for the selection of the optimum ratio of the mass and stiffness of the antenna depending on the desired aperture diameter. The main material used in construction is carbon fiber, which, thanks to its properties, is ideal for creating large-scale structures of high rigidity. Using the developed design of antennas on modern spacecraft communications will improve the quality of services provided to subscribers. The results of this work can be used to create systems of communication with the spacecraft in deep space research.
Siberian Aerospace Journal. 2016;17(2):408-417
408-417
INFLUENCE OF REVERBERATION ROOM FORMS ON THE MODAL DENSITY OF THE ACOUSTIC TEST RIG
Abstract
One of the main parts of the acoustic test rig is a reverberation room, where whole acoustic power is focused inside this room. The correct form of scientifically sound reverberation room and its volume can significantly optimize the cardinality and financial parameters of the test rig. The fundamental of the best installation is the density of the spectrum of natural frequencies (the density of modes) reverberation room. When you create a diagnostic rig, the dynamic properties of the spacecraft design can be taken into account. For example, to excite vibrations of the spacecraft on its own forms, it is necessary that in the spectrum of the reverberation chamber there are resonance frequencies of the object of the study. If the resonance frequency on the AC scale is too often or is not defined, the ideal camera for research spacecraft should have a continuous spectrum of natural frequencies. Although in practice the establishment of such cameras is not possible, the choice of the shape and size of the reverberation room has a significant impact on the density of natural frequencies, in other words, the proximity to the diffuse sound field. The problem of finding natural frequencies of acoustic oscillations reverberation rooms of different shapes is considered. The formulas for calculating natural frequencies room shaped parallelepiped, cylinder, hollow cylinder are given. Numerical simulation of the natural frequencies of the spectrum, with different ratios of linear sizes of rooms has been conducted. The results of the comparative analysis of the density of modes are given. The results of numerical studies have shown sufficient, for acoustic vibration tests, the density of the natural frequencies of the cylindrical room. The conclusion about the possibility of using plants to create a cylindrical shape of acoustic test facilities has been given.
Siberian Aerospace Journal. 2016;17(2):418-422
418-422
COMPARATIVE EVALUATION OF QUALITY OF CONTROL OF ASYNCHRONOUS ELECTRIC CONDENSATE PUMPS WITH SUBORDINATE AND MODAL CONTROLLERS
Abstract
He subject of the study includes dynamic characteristics of variable frequency induction motor with a modal control. The topic of research that received the greatest distribution system transmitter frequency with independent voltage inverter with pulse-width modulation is an asynchronous motor. The purpose of the work is to study the dynamic properties of the actuator with a modal control, as well as recommendations for the practical use of engineered control systems. In our research work we used the following methods. To solve the given problem the modern theory of electric, the theory of automatic control, the continuous Laplace transform, the method of transfer functions and state space by standard polynomial equations were used. Experimental study of the results obtained theoretically was held by mathematical modeling in time field using personal electronic computer. As a result, the analysis of the work of the modal systems and slave control of asynchronous electric motor as an example of the condensate pump is given. The estimation of the quality control processes of coordinates by analyzing the results of simulation system in the medium MatLab is given. The results can be applied in the system of variable frequency drive with more controlled output coordinates, for example, robotic machines and devices, electromechanical systems and other space vehicles. In the work the comparative analysis of systems and subordinate modal control is given. It was found that the benefits of the use of modal regulators compared to the same regulators built on the principle of subsidiarity control, is that: a) consideration of the frequency control system with induction motormodal regulator has approximately twice the speed compared with those of a subordinate authority; b) the modal regulators have greater noise immunity and are less sensitive to changes in the internal parameters of the motor, compared with controls built on the principle subordinate regulation; c) the stiffness of the mechanical characteristics of the drive system with a closed modal control is significantly higher than in the system with the slave control.
Siberian Aerospace Journal. 2016;17(2):423-431
423-431
Modernization of fuel submission systems of liquid rocket engines OF UPPER STAGES on the basis of innovative technical decisions
Abstract
For the delivery of spacecraft into the orbit with sophisticated high-specified accuracy the special self-contained propulsion boosters are used. The composition of propulsion boosters includes Sustainers Liquid rocket engine (LRE), which should have high reliability and a long service life in multiple starts in outer space. The article notes the expediency of improving the design and improvement of energy efficiency of the PB by upgrading the control systems of fuel engines based on innovative technical solutions. A number of design solutions aimed at improving anti-cavitation characteristics and efficiency screw centrifugal pump turbo pump assembly (TPA) engines are considered. A new design of the entrance to the pump, in which extra booster screw accommodates, which provides the increase of fluid pressure before the main auger pump has been worked out. The perspective hydraulic circuit of movement of the leaks in a closed circuit using the screw pump to the shaft of the turbine is given. To improve the efficiency of screw pump system confusors and diffusers are used, in which the energy obtained by the liquid during operation of the impeller is realized. Theoretical calculation of pressure drop of fluid held by the impeller .It is shown that these innovative technical proposals can reduce the mass-dimensional parameters of the pumps. The scheme of the device for command pressure of the automatic control and adjustment of the engine, which is stable and independent of the pressure with possible fluctuations in flow components in the pressure lines, is given. In general terms it has been justified how to configure a hydraulic system of this device enabling to adjust the pressure command value with high precision. Modernization of the fuel supply on the basis of innovative technical solutions KB Khimmash provides the basis for the development of advanced propulsion boosters.
Siberian Aerospace Journal. 2016;17(2):431-437
431-437
COMPUTER AUTOMATION OF ORGANIC WASTES “wET INCINERATION” installation for closed ecosystems
Abstract
Creation of long-term research bases on the Mars and other planets have been considered since 1960s. Diminishing time and labor spent on life-support issues are important in space missions as it allows increasing scientific and applied content of the mission. Physiochemical wastes treatment resulting to fertilizers for growing plants providing oxygen, water and food for crew is one of the processes required for crew operation in a closed volume. One of prospective candidates for the role of organic wastes treatment method for long-term space mission is “wet incineration” in hydrogen peroxide under alternating electric current. The method is relatively simple, compact, ecologically clean and efficient. Nitrogen left in forms relatively easily accessible for further treatment and inclusion into turnover processes is a significant advantage. The paper discusses features of the original organic wastes “wet incineration” installation automation in the transition from analog to digital control scheme of human exometabolites mineralization process applied to closed life-support systems. The work was aimed to embed “wet incineration” installation control system into information system of experimental model of space application bio technological life support systems to control the facility as whole entity. The control and monitoring programs were coded on Free Pascal and internal Arduino micro controller language. The original organic wastes “wet incineration” installation automatic control has been implemented. Process parameters data are saved in real time in formats comfortable for further mathematical processing in presence of such tasks.
Siberian Aerospace Journal. 2016;17(2):438-443
438-443
THE MEASUREMENT OF THE CONDENSATE FILM THICKNESS OF THE WORKING FLUID BY MEANS OF THE CAPACITIVE SENSORS IN THE LOW-TEMPERATURE RANGE HEAT PIPES
Abstract
The description of the automated capacitive meter of local thickness of the condensate film of working fluid in the low-temperature range short heat pipes are presented. The design, calibration results of the open small-sized capacitive sensors and electronics that allows the determination of the local thickness of the film of working fluid on the condensation surface of the within heat pipes designed for cooling the heat-stressed designs of spacecraft are presented. The cooling system of the spacecraft on the basis of heat pipes (HPs) can have complex spatial and different topological configuration. The movement of the working fluid in such systems must be carefully examined in the terrestrial environment and determined boundary and limit settings and ranges of stability of HPs work. For such studies modern measuring equipment, which must be inserted into the outlets of HPs to control the thickness, temperature and later the flow rate of the film coolant, is required. The developed electronic hardware, mounted on small circuit boards directly on the lids of short HPs, consists of a measuring and a reference frequency generators, mixer and low pass filter. Both generators are performed on two identical broadband amplifiers EL4551 (INTERSIL), providing amplification of signals with frequency up to 90 МHz. The scheme of each generator is created on the serial LC resonant circuit, in parallel to the capacitance of which is connect with the measuring and reference capacitive sensors in the measuring and reference HPs. With the outputs of the amplifiers of the measurement and reference signals are fed to the inputs of the balanced type mixer ADE-1, then the low pass filter, oscilloscope and a computer. The average time values of the condensate film thickness depending on the heat load on the capillary-porous evaporator have been measured. The measurement error does not exceed 2·10-3 mm. It is shown that the condensate film thickness decreases sharply with increase of heat load on the evaporator is a short low-temperature range HPs, thermal resistance of film on the condensation surface reaches 60 % of the total thermal resistance of the short HPs with capillary-porous evaporator.
Siberian Aerospace Journal. 2016;17(2):444-457
444-457
DESIGN AND TECHNOLOGICAL ASPECTS OF CREATION OF PRECISION PARTS WITH COMPLEX SHAPE FROM POLYMER COMPOSITE MATERIAL
Abstract
Polymer composite materials apply in various fields of engineering, such as aerospace, transport and sport. We presented some information about design and manufacturing the batch production of precisions parts with complex shape based on polymeric composite material - carbon fiber reinforcement plastic which we manufactured by resin transfer molding. We showed the main design requirements which we have to apply to raw material, such as polymer matrix and reinforcement, tooling and the construction of part and finish product. We indicated the main technological requirements that we have to take into account for choosing raw materials, such as polymer matrix and reinforcement, tooling and the construction of part and product considering the fact that the final products have to operate in space. We had some specific requirements because of that. The requirements by strength construction and shall construction are different. We used finite elements method for strength analysis of designed antenna reflector constructions based on carbon fiber reinforcement plastic and showed the results as well. We used finite elements method for strength analysis of designed X-shaped fitting constructions based on carbon fiber reinforcement plastic and showed the results. We used finite elements method for strength analysis of designed bracket constructions based on carbon fiber reinforcement plastic and showed the results. We delivered the major aspects about technological process of manufacturing precisions parts with complex shape based on carbon fiber reinforcement plastic by resin transfer molding.
Siberian Aerospace Journal. 2016;17(2):460-465
460-465
INFLUENCE of helium pressure ON THE synthesis efficienCY of ENDOHEDRAL METALLOFULLERENES
Abstract
One of the unique properties of fullerene molecular is the possibility to contain atoms and molecules inside the carbon cage. “Endohedral” is used for fullerene with species incorporated in the carbon cage. Endohedral carbon structures are the new class of nanosized objects with unique chemical and physical properties and advanced applications. A number of important tasks of electronic and aerospace engineering may be solved by investigation of endohedral metallofullerenes properties and their application, for example, for nanostructured super absorbent coatings and new aerotechnics. In this paper the method for fast determination of endohedral metallofullerenes content at the fullerene mixture which was synthesized with metal oxide addition is presented. The methods of mass spectroscopy and atom emission element analysis are determined at the technique. By the method of mass spectroscopy the type of endohedral metallofullerenes with atom-guest is registered and by the method of emission spectroscopy the quantity of that element which contained at the fullerene mixture. The technique may be used for rapid determination of endohedral metallofullerenes weight percents at the fullerene mixture in case if only one type of endohedral metallofullerenes is in fullerene mixture, and of endohedral metallofullerenes average content if there are different types of endohedral metallofullerenes at the fullerene mixture. The effective synthesis method, extraction and analysis of endohedral metallofullerenes are demonstrated on the example of Gd@C82.
Siberian Aerospace Journal. 2016;17(2):466-469
466-469
FORMATION OF structure and magnetic properties of nanostructured Bulk co-based alloys AT plasma spray deposition and dynamic compaction
Abstract
The bulk nanostructured CoFeNi-SiB alloys were prepared by dynamic compaction and plasma spray deposition techniques. The preparation of bulk samples includes several process steps: obtaining of rapidly quenched amorphous ribbon; annealing of ribbon to embrittlement; ribbon grinding in powder; and finally, plasma spraying or dynamic compaction. The investigations of structure and magnetic properties of bulk samples were carried out by X-ray diffraction, electron microscopy and correlation magnetometry. The amorphous/crystalline phase ratio was estimated using the technique of magnetic phase analysis. The effect of processing steps of bulk amorphous alloys preparing on the magnetic characteristics of the samples was investigated. The regimes of dynamic compaction (the loading pressure PL < 3.2 Gpa) and plasma spray deposition (power of the electric arc P < 20 kW, the substrate temperature substrate temperature Ts < 150 oC) were selected so that the saturation magnetization, exchange constant, Curie temperature, local anisotropy field, and ferromagnetic resonance linewight of the bulk samples are identical to those of the rapidly quenched Co58Fe5Ni10B16Si11 ribbon. It was found that the bulk materials produced by shock compaction technique as well as plasma spraying technique are nanostructured. A comparison between the magnetic properties of the CoFeNi-SiB alloys prepared by dynamic compaction and a plasma spray deposition techniques was carried out. The analysis of the magnetic hysteresis loops curves shows that plasma spraying does not cause a change of Hc value (0.3 Oe). The coercive field of shock wave compacted sample is slightly bigger than that of the initial ribbon (0.5 Oe).
Siberian Aerospace Journal. 2016;17(2):470-474
470-474
AUTOMATIC POSITIONING ON THE JOINT LINE DURING ELECTRON BEAM WELDING IN CONDITIONS OF ACTION OF MAGNETIC INTERFERENCE
Abstract
Positioning on the joint line during the electron beam welding is a difficult scientific and technical problem to achieve the high quality of welded joints in the aerospace industry, shipbuilding and power engineering. The final solution of this problem is not found. This is caused by weak interference protection of sensors of the joint position directly in the welding process. Eelectron- beam welding is often followed by indignations in the form of the magnetic fields leading to a deviation of an electron beam from an optical axis of a gun. The collimated X-ray sensor is used to monitor the beam deflection from the optical axis of the electron beam gun. The X-ray sensor is placed on the electron beam gun. The collimation slit of X-ray sensor is aimed at the optical axis of the gun. The method of synchronous detection is used to process information from the X-ray sensor. The method of synchronous detection uses the technological scanning of electron beam across the joint line. The technological scanning allows to select the signals of the first and second harmonics of the scanning frequency of the electron beam across the joint line. The authors analyzed the impact of the gap width in the joint and the joint deflection from the optical axis of the gun on the output signal of the collimated X-ray sensor. The authors propose a two-circuit system for automatic positioning of the electron beam on the joint connection during the electron beam welding in conditions of action of magnetic interference. This system includes a circuit of joint tracking and circuit of compensation of magnetic fields. Two-circuit system uses a secondary-emission sensor to monitor the position of the joint. The proposed system is stable.
Siberian Aerospace Journal. 2016;17(2):475-483
475-483
INCREASE OF THE PURITY OF METAL PRODUCTS SURFACES WITH APPLICATION OF NANOTECHNOLOGIES
Abstract
It is known that the quality of the surface of metal products machinery and equipment measured at the value of the roughness significantly affects their performance. This also applies to the impellers turbopump units (TNA) of liquid rocket engines (LRE), the cast of superalloys, because this figure significantly affects the volumetric flow of the fuel components. However, due to the difficulties of conducting full-scale experiment on LRE, in that article the data from the cast steel ship propellers (SP) were used. There is a certain similarity between geometries of SP and functions of TNA. The similarity of the features and technologies of their production, both of which, firstly, produce a casting: impellers TNA - investment casting process, SP - casting in sand-clay molds, secondly, there is the similarity in the materials of the molds - in both cases, their basis is the sand, and the second component is a liquid binder. At the same time when molding in sand-clay parts often affects the penetration, firmly linked with the body of the casting crust, formed as a result of penetration of liquid metal into the pores between the grains of sand form, which is subsequently removed in a variety of ways, usually with the deterioration of surface cleanliness. To reduce metal penetration work surfaces forms are coated with fireproof paint, representing a suspension of the powder filler (graphite, powdered quartz, etc.). However, the use of such paints does not prevent the formation in castings of metal penetration due to the particle size of the fillers. In this paper a nonstick paint containing nanopowders of refractory chemical compounds is used, the use of such coatings is almost completely prevents the formation of burnt-on steel castings, including the one described in the work of the ship propeller, and, as a result, increased clarity and improved surface quality. The obtained results can be used in the manufacture of molds for the casting of the impellers TNA .
Siberian Aerospace Journal. 2016;17(2):484-489
484-489
FPGA FUNCTIONAL COMPLETE TOLERANT LOGIC ELEMENTS FOR AEROSPACE COMPUTER SYSTEMS
Abstract
Functional and complete (in the sense of Theorem Post) tolerant elements have been proposed as a paradigm spread structurally stable computers, proposed by Professor V. A. Kharitonov, at the turn of the 90s of the twentieth century, on the register transfer level. Structurally stable computers have the ability to emulate the desired command system in case of failure of individual teams from the original set. In turn, functionally complete tolerant logic elements FCTLE have the ability of maintaining the functional completeness of a given model of failures. In 1996-1997 FСT were obtained function model considering the constant failure of one of the four inputs of the corresponding element (stuck-at-0; stuck-at-1). They were the composition of AND, OR, NOT logic functions. Of these, the practical significance of known functions 2OR-2AND-NOT; 2AND-2OR-NOT. When adding Bridging Faults: (Dominant; Wired AND, OR; Dominant AND / OR), it proved that the cardinality of the set of functions FPT reduced, but 2OR-2AND-NOT; 2AND-2OR-NOT maintain tolerance. Then there were the issues of maintaining the functional completeness at the transistor level - for internal failures logic element (valve) - KMOS transistors (stuck-closed transistor - permanently closed, stuck-open transistor - permanently open. It is shown that the functional completeness is preserved in case of failure of one transistor or a top of the circuit - connect “+” power supply or lower - bus connection “Ground”. Then there is understanding that can be similar to conserve not only the functional completeness, but also the realization of a function at the level of a single element. The article features FCTLE elements included in the FPGA with the so-called LUT (Look Up Table).
Siberian Aerospace Journal. 2016;17(2):490-497
490-497
WATER PURIFICATION FROM CHROMIUM IONS IN A DIAPHRAGM ELECTROLYZER
Abstract
In the production of rocket and space technology electrochemical processes are applied that is the reason of pollution of wastewater with metal ions. The strict requirements of the environmental authorities do not allow dumping sewage waste water containing metal ions which concentration exceeds the maximum permissible values directly into water bodies or sewerage. The greatest difficulty is water treatment from hexavalent chromium. Proposed methods for purification of hexavalent chromium - electrocoagulation method, the method galvanokoagulyatsii, sorption methods, combined methods have drawbacks, such as significant power consumption, a considerable consumption of soluble metal anode passivation anodes need for large excesses of reagent (iron salts), large quantities of sludge and the complexity of its dehydration, high cost and scarcity of sorbents, high consumption of reagents for regeneration and other sorbents. Water purification from chromium using a non-diaphragm electrolyzers with soluble iron anode diaphragm electrolyzers are used to change the active reaction and the redox potential of the medium. We present experimental setup with coaxial arrangement of electrodes and an inert diaphragm separating the water, the calculation time of the ion migration from the cathode to the anode chamber. Anion concentration of chromium was determined by atomic absorption spectroscopy. The initial concentration of the anion of the chromium in the cathode chamber is equal to 892 mg / l, final - 669 mg / liter. The degree of purification of water by chromium is 25 %. Insufficient degree of purification can be explained by the following factors: the migration of chromium anions from the cathode chamber into the anode space occurs opposite directional diffusion flux due to the appearance of a gradient of concentration of anions with increasing concentration of like charged anions in the anode chamber increases the Coulomb repulsion force, which limits the influx of anions anode chamber. Since the waste water engineering plants contain less than 0.5 mg / L chromium, the distance between the like-charged ions causing considerable repulsive force decrease. In this connection it should expect an increase in the degree of purification and the proposed method can be used for purification of wastewater from metal ions to the maximum permissible concentration.
Siberian Aerospace Journal. 2016;17(2):498-501
498-501
Effect of Germanium single crystals annealing on the behavior of oxygen impurity
Abstract
Production of semiconductor Germanium contributes to the development of aerospace instrumentation. Dislocation-free Germanium single crystals are used for making effective space-based solar cells. The crystals with extremely low concentration of impurities and defects are used for the manufacturing of digital devices in distributed power systems of the onboard space equipment. Oxygen is one of the main impurities in Germanium, which impairs the properties of crystals and leads to formation of dislocations. The present research has been aimed at analyzing the effect of Germanium single crystal annealing on the behavior of oxygen impurity. Oxygen-dissolved in Germanium has been characterized using Fourier transformed infrared spectrometry. The oxygen concentration in crystals was determined based on optical density from the absorption band at 843 cm-1. It is established that oxygen dissolved concentration in Germanium is variable from 0,2·1016 to 1,3·1016 сm-3 depending on their quality. The effect of Germanium single crystals annealing on the behavior of oxygen impurity has been studied in the temperature range of 350-450 °C. It was found that oxygen concentration and form of its presence varies under the influence of annealing. It was established that oxygen band maximum shifts from 843 to 856 cm-1 when its concentration increases under the influence of annealing in the atmosphere with 1≤ ≤ 103 Pa. The annealing at lower leads to decrease in the oxygen band intensity of the 843 cm-1 due to the formation of thermal-donors on the basis of interstitial dissolved oxygen. These results can be used in the semiconductor Germanium technology to obtain single crystals with necessary oxygen content and form of its presence, thus, with therefore, controlled due to the properties.
Siberian Aerospace Journal. 2016;17(2):502-507
502-507
PREDPOSYLKI ISPOL'ZOVANIYa UChETNO-ANALITIChESKOGO OBESPEChENIYa PRI PLANOVOM OBNOVLENII FONDA OSNOVNYKh SREDSTV
Abstract
The preconditions of necessity for the creation of accounting and analytical support of the process of updating of the fixed assets of the company of the RCP are investigated. The study of the current practice of scheduled updates production assets has been conducted, the issues associated with the risks of violation of financial stability and solvency of the enterprise have been identified. The most significant factors arising in the process of creation, development and use of fixed assets, the effect of which is manifested through causal relationships of processes and phenomena occurring in the course of accounting and analysis of fixed assets as well as the search of investment resources for updating have been shown. This confirms the authors ’ advice about the need to develop a comprehensive tool in the form of accounting and analytical system, allowing to monitor the process of updating the fixed assets on the one hand and the set of controlled parameters on the other hand. The main stages of the process from the point of view of accounting and analytical component have been described. The requirements for the accounting and management system with reference to the control parameters, which is especially important for the modern organization of enterprise management of the RCP, have been formulated. The necessity of the establishment of the company PSC accounting and analytical system, allowing a comprehensive approach to the problem of renewal of fixed assets and create efficient production-technical base for innovative development of all its divisions, able in the long term to replace an existing part of the products and services, and to develop its technological and experimental-industrial base, has been revealed and substantiated. The cumulative effect of the general possibilities of integrating accounting and analytical systems, plant and equipment upgrade will allow using it to maximum effect, providing, in turn, greater coherence, thereby enhancing the synergy effect, which consists in the fact that the overall result of the concerted action is higher than the simple sum of the individual results.
Siberian Aerospace Journal. 2016;17(2):510-517
510-517
THE ROLE OF COMMERCIALIZATION OF INNOVATIVE POTENTIAL OF SPACE INDUSTRY ENTERPRISE
Abstract
The article examines the role of commercialization of the innovative potential of enterprises of space-rocket industry (SRI). In today’s economy the effective activity of industrial enterprises, ensuring a high rate of development and maintenance of high competitiveness largely depends on their innovation activities. At present, innovations, created at industrial environment, open up new market opportunities for enterprises. The unique advantage of the space industry is a strong scientific and technical base, including a highly qualified workforce. As a result, the SRI enterprises have accumulated a unique innovative capability that enables the implementation of technologically complex tasks to be commercialized in applied science business, which is the main difference of the modern innovation economy. A number of scientific directions of the space industry today is cost-effective and attractive investment areas of investment. Among the key areas of the market demand for civilian goods SRI, we can distinguish such important sectors of the economy as transport, communications and telecommunications, electronics, oil and gas industry, fuel and energy industry, healthcare. There is a mutual approach, combining the development of links between science and economic structures in order to create favorable conditions for carrying out economic activities. Such process can be described as the process of integration of military production to civilian sphere of the economy. SRI enterprises need to expand the object of commercialization. Civil production must be carried out on the basis of the results of the innovation activity at different stages of the innovation process, which is a particular space rocket product - from the idea to the patented product or technology. The commercialization of innovative potential of the SRI enterprises is the most important area to address some of the problems that have arisen as a result of the reduction of the state orders and capital investment, which resulted in the rocket and space industry in a serious crisis.
Siberian Aerospace Journal. 2016;17(2):518-522
518-522
THE SELECTION TOOLS OF THE PUBLIC-PRIVATE PARTNERSHIP MODEL FOR the IMPLEMENTATION OF THE INFRASTRUCTURE PROJECTS IN THE AEROSPACE COMPLEX
Abstract
In the long-term socio-economic development of the Russian Federation aerospace complex occupies a priority position. It is expected in the future not only to preserve the existing position of the domestic aerospace industry in the global market, but also become the leaders in this segment of the economy. Nowadays solving of the problem is becoming more complicated. In relation to the Russian Federation financial and technological sanctions have been imposed by developed countries in the world. To solve the existing problems primarily internally reserves for economic development, including the aerospace industry must be found. It's necessary to intensify the investment activity in the country and more efficient to use available public investment resources. One of the universal solutions of the tasks, of course, is wide use of public-private partnerships, including the aerospace sector, in the interests of the Russian state. In our country the use of public-private partnership is limited to a number of circumstances. One of them can be attributed to problems associated with application of the conceptual framework and the practical choice of the most effective mechanisms for implementing public-private partnership. The conceptual problem is that in Russian methodological literature there is no stable definition of concepts such as the model and the form of public-private partnerships. One and the same object is quite often called both a model and a form that makes some confusion during the implementation of this partnership in practice. The study presents different points of view regarding the content of the concepts of model and shape. The author’s interpretation of these concepts in relation to the subject is given. Two groups of factors influencing the choice of the public-private partnership model in the Russian context have been highlighted. On their basis the principles of selection models, which take into account peculiarities related to the activities of public and private partner have been formulated. The principles allowed the author to develop a matrix of criteria selection of the public-private partnership model have been formulated. Additional classification features, which allow identifying the model of public-private partnerships in aerospace complex, have been identified. As a result, the technique of choosing the model of public-private partnerships in the aerospace sector, based on the proposed matrix has been offered.
Siberian Aerospace Journal. 2016;17(2):523-529
523-529
ASSESSMENT TOOLS OF THE LEVEL OF SCIENTIFIC-TECHNOLOGICAL DEVELOPMENT OF ENTERPRISES OF THE MILITARY-INDUSTRIAL COMPLEX
Abstract
The article proves the relevance of evaluation techniques for scientific and technological development in military-industrial complex. Integrated factors of scientific and technological development were elaborated. The structure of the integrated factors was identified. The integrated factor of technological development includes: relative share of innovative goods, works and services in the overall volume of provided goods, works and services; effective output of technological innovations; military technologies commercialization in civil production. The integrated factor of scientific development consists of the following key indicators: scientific projects output, coefficient of researchers average age, share of researchers aged up to 39 in the total number of researchers, internal expenses share for development and research. Each indicator was validated to be in the structure of the integrated factor. The methods for aggregated indicator calculation were proposed. Reference value and weight of each indicator in the integrated factor were identified and validated. General and particular formulas for integrated factors of scientific and technological development were determined. In general formulas all variables were specified. Particular formulas use default factors weight and actual reference values. Their change intervals were identified. The level of scientific and technological development of military-industrial complex was described on the basis of the integrated factors values. The obtained results will be used as a method to evaluate scientific and technological development of military-industrial complex facilities. The method includes cross estimation of integrated factors and strategic decisions matrix. The matrix designed for a particular military-industrial complex facility will help to design and accomplish actual development strategy.
Siberian Aerospace Journal. 2016;17(2):530-536
530-536