Informatics, computer technology and management. Рубрика в журнале - Siberian Aerospace Journal
Attribute features application in specification of regression model of apartments cost
Статья научная
In the study of statistical data with a pronounced endogenous variable, it is necessary to identify factors (explanatory variables) that have a strong impact on the result. In this, factors can be both quantitative and attributive. To assess influence of numerical features, regression analysis methods can be used. Influence of attributive features is not taken into account. However, often these are they who make the decisive contribution to variation of the result. It is necessary to develop methods for analyzing influence of attributive features and accounting for these features in regression models. On the example of sets of apartments proposed for sale in the city of Krasnoyarsk, a new method is used to assess influence of attributive features on the quantitative using ranking them in accordance with their influence on the endogenous variable. Method of fictitious variables is used to analyze the attribute features. Each attribute with m values is assigned (m-1) dummy variables and a regression model is constructed. Influence of exogenous variables can be expressed using standardized regression coefficients. In this case, influence of attributes can be estimated by cumulative correlation coefficient calculated on the basis of a regression model with fictitious variables. For further research, set is proposed to rank, assigning each element a "rank" – value of a standardized coefficient which reflects closeness of the relationship with the endogenous variable. Thus, all features have a numerical value. A standardized regression model is constructed. Proposed approach can be used in the analysis of statistical aggregates, units of which are characterized by quantitative and attributive features.
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Статья научная
For successful technological process in automated control systems it is necessary to maintain technological parameters constantly at the required level, which is ensured by the use of automated process control systems (APCS). The classical solution of this problem is the application of control devices of various types, the choice of which directly depends on the system under consideration and the requirements to it. The leading position among the automatic control system regulators for the last decades belongs to the proportional-integral-differentiating (PID) regulator, which efficiency of application in the technological process is defined by the speed and accuracy of its work. These qualities directly depend on the correct setting of the regulator parameters. The synthesis of regulators requires using of modern computer-aided design systems. The article presents the method of automatic setting of PID-regulator of the dynamic system of high order with negative feedback on the example of automatic room temperature control system. The modern Russian environment of dynamic simulation of technical systems SimInTech applied at a number of nuclear, oil refining and aerospace enterprises is used as the environment for system model development, as well as the process of its analysis and optimization. The main components of the system and transfer functions of its elements are presented. The stepby- step description of the process of project construction from standard software blocks and submodels, interacting through a single database with the use of built-in programming language, is described. The use of the built-in block of SimInTech visual simulation environment optimization for automated search of PID-regulator parameters is described in details and illustrated. The advantages and disadvantages of this adjustment method revealed during the project implementation are listed.
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Automated system for detecting anomalies of periodic electrical signals
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The aim of the work is to develop an automated system for detecting anomalies of periodic electrical signals with improved characteristics of the speed and efficiency of search. To solve this goal, the analysis of the problem of detecting anomalies of periodic electrical signals measured from electronic equipment was carried out and its relevance was substantiated. A hardware and software system for detecting anoma-lies of periodic electrical signals has been developed, which makes it possible to automate the testing pro-cess and increase the efficiency of detecting malfunctions of electronic equipment for various purposes. The improvement of the aforementioned characteristics was achieved due to a new test method underlying the implementation of the proposed system and protected by the patent of the Russian Federation for an inven-tion, as well as due to the high-quality implementation of software and hardware. When solving the set tasks, the methods of algebra-logic, mathematical statistics and object-oriented programming were used. The results of developing hardware, software and test algorithms are presented. A program for an electronic computer that implements control of the proposed hardware-software system is described.
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Статья научная
Technologies and production widely use composite materials now. “Mechanics of deformable solids” was formed as a science based on the study of materials used in the 19th and 20th centuries. Modern composite materials require new theoretical and experimental studies. Determining the stresses and deformations that occur at the points of contact of the matrix with the fibers is a special problem. Composites with a plastic matrix play an important role in modern technology. These materials successfully cope with cracking and significantly slow down the growth of cracks. In this article, the problem of the stress state of a composite beam with an elastic-plastic matrix and elastic fibers located along the axis of the beam is solved. It is assumed that in the zone of contact of the matrix with the fibers, according to the model of Yu. N. Rabotnov, a constant tangential stress is realized, less than the yield strength of the fiber. One end of the beam is fixed, and a constant force applied to the center of gravity coinciding with the origin of coordinates acts on the second. It is assumed that at the free boundary of the beam and at the points of contact of the beam with the fibers, the stresses reach the plasticity limit. The problem is solved with the help of conservation laws. This makes it possible to find the stress state at an arbitrary point of the section as a calculation of integrals along the outer boundary of the beam and the boundaries of the matrix and fibers.
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The article presents a computational and experimental study of the dynamic characteristics of a spacecraft telescope frame mock-up. The main attention is paid to the methodology of vibrodynamic tests using a three-component laser vibrometer and the creation of a finite element model of the mock-up under study. To analyze the dynamics of the structure, the main criteria such as modal parameters, model validation and harmonic analysis are defined. Particular attention is paid to the effect of experimental data transformation on the accuracy of calculating the modal assurance criterion. The research investigates telescope frame mock-up, which is a truss structure fixed on springs. The tests were carried out by applying a random impact of the “white noise” type. The dynamic characteristics of the structure were obtained, including the natural frequency of oscillations, which was 93.7 Hz. The experimental data were compared with the results of finite element modeling, which showed a significant discrepancy between them, especially in the area of natural frequencies. This indicates the need to adjust the finite element model. Various criteria for assessing the compliance of calculated and experimental models are considered, such as the coordinate modal assurance criterion (COMAC), the modal assurance criterion (MAC), the cross signature assurance criterion (CSAC) and the cross signature scale factor (CSF). These criteria help to assess the degree of coincidence of vibration modes and frequency characteristics. An analysis of the effect of transforming experimental data into different units of measurement on the results of calculating these criteria is carried out. It is concluded that the current calculation model requires revision and clarification of parameters to achieve better compliance with reality.
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Статья научная
The paper proposes an analytical method to solve the problem of magnetometer calibration for a model that considers the vector of temperature dependence of zero offsets for each of the measuring axes of the magnetometer unit and the matrix of linear temperature dependence of each of the members of the sensitivity matrix, scaling the signal based on the actual sensitivity of each axis and including linear off-axis effects. When solving the problem of determining the calibration parameters of the magnetometer unit, it is taken into account that for measurements with any spatial orientation of the magnetometer unit, the magnitude of the measured magnetic field strength vector is preserved and is a known model value. A penalty function of 24 variables equal to the sum of the squares of the residuals is introduced into consid-eration. The algorithm for solving the problem of calibrating the measuring axes of the magnetometer unit is reduced to searching by the method of least squares for such values of the variables of this function that, with a given set of vectors of magnetometer measurements, provide it with a minimum. For this purpose, the specified function is examined for an extremum. Based on the necessary condition for the extremum of the penalty function, a system of 24 equations in the 24 variables is formed, which, for convenience, is di-vided into three systems (each of them is a system of 8 linear algebraic equations in the 8 variables). It is proved that the main matrix of each of these three systems is an invertible, from which it follows that each of them has a solution, and only one. The components of the solutions of these systems (the coordinates of the stationary point of the penalty function) are found using Cramer's rule. It is proved that the second differential of the penalty function at the found stationary point is positive, from which it follows that this point really provides the minimum of the specified function.
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Статья научная
Modern and promising dynamic systems of aviation weapon systems of the Aerospace Forces (hereinaf-ter for brevity in the text – the system) are characterized by a more complex structure and increased re-quirements for reliability and efficiency of functioning. Moreover, systems of generation 4 ++ and 5 are quite unique and (or) small-scale, and their constituent elements are basically miniature and expensive, therefore, a prerequisite for fulfilling the requirements for traceability to systems and constituent elements is the maximum possible preservation of the quality of the initial basis with the inevitable new interpreta-tion of additional information. Further introduction of artificial intelligence technologies into the practice of solving problems of technical diagnostics makes it possible to obtain adequate results with almost any accuracy. The reliability of the results will be determined solely by the punctuality of the data assignment and the completeness of the mathematical description of systems, processes and events in the subject area under consideration. Therefore, it should be expected that the further development of the theory and prac-tice of technical diagnostics will follow the path of a deeper study of the physical processes occurring in systems, and a more accurate mathematical specification of procedures for finding the place of failure of systems. The aim of the work is to establish the development of an interconnected set of mathematical and logical block diagrams for obtaining and applying diagnostic knowledge in the software and mathematical support of modern and advanced onboard means of monitoring the technical state of systems. The priority direction in such studies is the differentiated selection of approved methods of technical diagnostics with the choice of the appropriate mathematical and algorithmic apparatus for direct probabilistic modeling of systems. A block diagram is presented and a variant of the practical application of the developed algorithm for sequential recognition of system failures (hereinafter referred to as an algorithm, if it is clear from the context of the presentation of the material that it is the developed algorithm) is considered. By using the algorithm, there is no need for decomposition of systems, and the potential for multiple repetitions of the results of a random process of changing the technical states of systems predetermines the possibility of ob-taining large samples with high accuracy of software compilation.
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Comparative analysis of selection and replacement schemes for genetic programming
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The selection mechanism in genetic programming has attracted attention of many researchers, as a result lexicase selection and its variants have been proposed. However, the replacement schemes are often out of the scope of most studies on genetic programming. In this paper, the effects of different selection mechanisms are studied, when they are applied to both parents’ selection and replacement. The aim of the study is to evaluate the efficiency of different parent and environment selection schemes in genetic programming. For this in the paper the four-parent selection, seven replacement are compared and two methods for selecting first parent in a pair, giving a total of 56 combinations. The experiments are performed on a set of 10 regression problems from the PMLB dataset collection, and the determination coefficient is used as a performance metric. The Mann-Whitney statistical tests and Friedman ranking is used for the analysis of the performance values. The analysis of the results show that the down-sampled lexicase selection can is an efficient mechanism, selecting current individual as one of the parents could be beneficial, and that either pair-wise comparison or selection of best of parents and offspring is an efficient replacement strategy. The results obtained in this study can be applied to improve the efficiency of solving symbolic regression problems, which often arise in the aerospace industry, for example for predicting solar panels degradation parameters, or antenna radiation patterns.
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Статья научная
The paper proposes the use of clustering methods to determine the most appropriate number of fuzzy terms when building a genetic fuzzy system. At the same time, a fuzzy logic system is used to solve data classification problems and is automatically generated by a genetic algorithm. We used a genetic algorithm with the encoding of terms and classes in a binary string, while each individual encoded a rule base. To build a rule base, it is necessary to set such a parameter as the number of fuzzy terms, since it significantly affects the quality of the generated classifiers. A comparison of the most well-known algorithms such as DBSCAN, k-means and the mean shift algorithm was carried out to identify the best data clustering meth-od. Computational experiments were carried out on several data sets to evaluate the effectiveness of the selected number of fuzzy terms. According to the results, it was determined that the mean shift algorithm selects such a number of terms that allows building more accurate classifiers in comparison with two other methods involved in testing. A comparison was also made with alternative classification methods such as k nearest neighbors, support vector machines and neural networks, as a result of which the proposed method showed comparable classification quality. The developed approach to automating the determination of the number of terms makes it possible to exclude manual selection of granulation for various data, reducing the cost of creating an effective fuzzy system for the classification problem.
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Comparison of methods for initializing starting points on the optimization genetic algorithm
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The way to initialize the starting points for optimization algorithms is one of the main parameters. Currently used methods of initializing starting points are based on stochastic algorithms of spreading points. In a genetic algorithm, points are Boolean sets. These lines are formed in different ways. They are formed directly, using random sequences (with uniform distribution law) or formed using random sequences (with uniform distribution law) in the space of real numbers, and then converted to boolean numbers. Six algorithms for constructing multidimensional points for global optimization algorithms of boolean sets based on both stochastic and non-random point spreading algorithms are designed. The first four methods of initialization of Boolean lines used a random distribution law, and the fifth and sixth methods of initialization used a non-random method of forming starting points-LP sequence. A large number of optimization algorithms were restarted. Calculations of high accuracy were used. The research was carried out on the genetic algorithm of global optimization. The work is based on Acly function, Rastrigin function, Shekel function, Griewank function and Rosenbrock function. The research was based on three algorithms of srarting points spreading: LP sequence, UDC sequence, regular random spreading. The best parameters of the genetic algorithm of global optimization were used in the work. As a result, we obtained arrays of mathematical expectations and standard deviations of the solution quality for different functions and optimization algorithms. The purpose of the analysis of ways to initialize the starting points for the genetic optimization algorithm was to find the extremum quickly, accurately, cheaply and reliably simultaneously. Methods of initialization were compared with each other by expectation and standard deviation. The quality of the solution is understood as the average error of finding the extremum. The best way of initialization of starting points for genetic optimization algorithm on these test functions is revealed.
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Compound bending of an orthotropic plate
Статья научная
The problem of longitudinal-transverse deformation and strength of an orthotropic plate on the action of a local transverse force and stretching along the contour of the membrane forces is studied. The direction of laying the fiber of a unidirectional composite that provides the lowest level of stress and deflection is determined. In the zone of application of concentrated force in thin-walled structures, significant bending moments and shear forces occur, which are a source of stress concentration. To reduce stresses, the method of plate tension by membrane forces applied along the contour is chosen. The maximum possible order of membrane tension forces is selected, which provides conditions for the strength and rigidity of the solar panel plate structure, which has a hinge-fixed support along the contour. Pre-tensioning the plate web allows to reduce the stress by 50 times. The problem of compound bending of isotropic and anisotropic plates when applying transverse and selection of longitudinal loads, with restrictions on strength and stiffness, can be called a problem of rational design of the structure. The resulting equations and calculation program can be used in the design of plate structures, as well as in the educational process.
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Статья научная
If a system of differential equations admits a group of continuous transformations, then the system can be represented as a set of two systems of differential equations. As a rule, these systems have a smaller or-der than the original system. The first system is automorphic, characterized by the fact that all its solutions are obtained from a single solution using transformations of this group. The second system is permissive, its solutions, under the action of the group, pass into themselves. The resolving system carries basic infor-mation about the source system. Automorphic and resolving systems, two-dimensional stationary elasticity equations are studied in this work. They are systems of the first-order differential equations. Infinite series of conservation laws for a resolving system of equations and an automorphic system are constructed for the first time in this work. Since the two-dimensional system of elasticity equations is linear, there are infinitely many such laws. In this paper, an infinite series of linear conservation laws with respect to the first derivatives is constructed. It is these laws that made it possible to solve the first boundary value problem for the equations of elasticity theory in the two-dimensional case. These solutions are constructed in the form of quadratures, these quadratures are calculated along the contour of the studied area.
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Constraint handling genetic algorithm for feature engineering in solving classification problems
Статья научная
Feature engineering in machine learning is a promising but still insufficiently studied direction. Creating new feature space from an original set allows to increase accuracy of the machine learning algorithm chosen to solve complex data mining problems. Some existing selection methods are capable of simultaneously increasing accuracy and reducing feature space. The reduction is an urgent task for big data problems. The paper considers a new machine learning approach for solving classification problems based on feature engineering methods. The design of informative features is carried out using extraction and selection methods. Based on the initial data, new sets of characteristics have been created, which include the original characteristics and characteristics obtained by the method of principal components. The choice of an effective subset of informative features is implemented using a genetic algorithm. In order to avoid overfitting and the creation of trivial classifiers, restrictions are imposed on the fitness function of the genetic algorithm, requiring a certain number of features of the original sample, as well as a certain number of features obtained by the principal component method. A comparative analysis of efficiency of the following classification algorithms is carried out: k-nearest neighbors, support vector machine, and a random forest. Efficiency research experiments are carried out by solving applied binary classification problems from the UCI Machine Learning repository of machine learning problems. The macro F1-score was chosen as an efficiency criterion. The results of numerical experiments show that the proposed approach outperforms the solutions obtained using the original data set and the performance of random feature selection (the low bound for the results). Moreover, the accuracy enhancement is obtained for all types of problems (data sets that have more features than values). All results are proved to be statistically significant.
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Construction of high-precision low-dimensional MgFE using local approximations and generating FE
Статья научная
Composite structures (bodies), in particular, plates, beams, shells, are widely used in aviation and rocket and space technology. To analyze the stress state of elastic composite bodies (CB), the method of multigrid finite elements (MMFE) is effectively used, which is implemented on the basis of the Lagrange functional (in displacements). When constructing a multigrid finite element (MgFE), briefly a standard MgFE, using known procedures, a small base grid is used, which can be arbitrarily small, and large ones nested in a small one. The fine grid is generated by the partition of the MgFE, which takes into account its inhomogeneous, micro-inhomogeneous structure within the framework of the micro-passage. Large grids are used to reduce the dimension of the MgFE. The following is typical for a standard MgFE. Any large grid of a standard MgFE and corresponding approximations of displacements are determined on its entire region. This leads to an increase in the dimension of the standard MgFE with an increase in its order of accuracy, since in this case approximations of high-order displacements are determined on large grids. To reduce the error of solutions, high-precision MgFE are used, i. e., of a high order of accuracy, which have a large dimension. However, the use of high-precision MgFE is difficult, since they form discrete models of high-dimensional bodies. In this paper, we propose a method of local approximations (MLA) for constructing high-current MgFE of small dimension (short - small-sized MgFE), which are used to calculate elastic homogeneous and CB by MgFE. Two types of small-sized MgFE are considered. Small-sized MgFE of the 1st type are designed on the basis of standard ones with the use of local approximations of displacements, which are determined on the subdomains of standard MgFE, of the 2nd type - with the use of finite element generators (FE). The brief essence of the construction of small-sized MgFE of the 1st type is as follows. According to the MLA, we define a smaller Н grid on the V0 region of the standard MgFE than its base one. The V0 region is represented by the boundary and inner regions. The boundary (inner) regions have a common boundary, which does not degenerate into a point (do not have a common boundary), with the V0 region. On the boundary (inner) regions, we define large grids that are embedded in a small Н grid and generate local approximations of small (high) order displacements. On the V0 region, using local approximations of the displacements of the boundary and inner regions, we construct the MgFE. Then, using the condensation method, we express the movements of the internal nodes of the MgFE through the movements of the nodes lying on its boundary, i.e. on the boundary of the V0 region. As a result, we obtain a high-precision Vp MgFE of small dimension, i.e. a small-sized MgFE of the 1st type, the dimension of which is equal to the dimension of the standard one. It is important to note that with an increase in the order of accuracy of the Vp MgFE, its dimension does not change, i.e. it does not increase, and therefore it is called a highprecision MgFE of small dimension, i.e. small-sized. The procedure for constructing small-sized MgFE of the 1st type is described in detail. As is known, the calculation of the static strength of structures is reduced to determining the maximum equivalent stresses for them, the determination of which with a small error for CB is an urgent problem. Calculations show that small-sized MgFE of the 1st type generate maximum equivalent stresses in CB, the errors of which are 25 50 smaller than the errors of analogous stresses obtained using standard ones, on the basis of which small-sized, i.e. small-sized MgFE of the 1st type are more effective than standard ones. The use of small-sized MgFE of the 1st type in MMFE calculations makes it possible to determine the maximum equivalent stresses with a small error for large CB partitions. The construction of small-sized MgFE of the 2nd type is shown, which are designed on the basis of standard high-precision MgFE with the use of generating FE. A small-sized MgFE of the 2nd type has the same order of accuracy as the standard one, but its dimension is smaller than the dimension of the standard one. The advantage of small-sized MgFE of the 2nd type is that they give rise to discrete CB models of smaller dimension than standard ones.
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Detection of information system objects interaction with DGA domains
Статья научная
Currently, malware developers are actively using domain name generation technique called DGA to es-tablish communication between malware and its command centers. Domain name generation in accord-ance with the given algorithm allows malicious software to bypass information protection tools blacklists, thus making blacklists ineffective, and establish a communication channel to receive control commands and parameters, as well as to transfer information from the information system to external resources con-trolled by attackers. Thus, it is necessary to develop new approaches to DGA generated domain names de-tection using DNS traffic of an information system. During the research, the authors have developed a solution for detecting information objects interaction with DGA domains based on the use of machine learning. The detection of this interaction occurs in two stages. On the first stage the classification task is being solved for each DNS name from overall infor-mation system DNS stream. On the second stage, for each DNS name classified as DGA, corresponding DNS query is being enriched using data from external sources and a final decision about the malicious nature of the query to resolve this DNS name is being made, followed by a notification of a security admin-istrator via e-mail channels. The paper describes the process of developing a classifier based on machine learning, defines the input data of the DNS name necessary for classification, presents the results of classifier training on a repre-sentative set of test data. The logic of making a decision about the malicious nature of DNS queries has been substantiated. The developed solution was tested using an experimental stand. Some recommenda-tions for correct classifier operation support are proposed. The application of the developed solution will make possible posteriori detection of information interac-tion of malicious software working on compromised information objects with the servers of attackers com-mand and control centers.
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Determination of coupling loss factors for beams connected at an angle
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The use of a statistical energy method for the analysis of dynamic systems assumes that coupling loss factors of subsystems must be known. Coupling loss factors show what part of energy moves from one subsystem to another. They are included in the system of energy balance equations and must first be determined analytically, experimentally or numerically. The most promising of the listed methods is a numerical one. In particular, this paper uses a finite element method. The purpose of this study is to determine the coupling loss factors of two subsystems in two versions of their relative positions. The basis is the model of an L-shaped connection of two beams, which is quite common in such studies. L-shaped connections of structural parts are often found in building structures, but in other industries, such as the development of space and aviation technology, structural elements are often connected at an angle other than 90°. Since energy methods (EMs) can also be applied to aerospace industry, when developing approaches to analyzing structures using such methods, it is useful to know how the energy parameters of a system, in particular coupling loss factors, change depending on the fact at what angle their components are connected. The paper considers two system configurations: in the first, the beams are connected at a right angle, in the second - at an angle of 45°. The coupling loss factors of the beams are calculated for both system configurations. Conclusions are drawn about the possibility of disseminating the results obtained to more complex structures, namely spacecraft structures.
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Статья научная
The article describes the results of tests that have been carried out at the manufacturing plant of refrig-eration devices. These results have made it possible to estimate the capability of using a new method of testing refrigeration devices for compliance with the standards established by GOST, which determine the specific heat and power properties of each refrigeration device, depending on its type (single-chamber or with two-chambers, with one compressor or with two, etc.), passing acceptance tests. The graphs of the active power of the device will be presented when it is connected to the power supply network and the de-pendence of the change in the power graph depending on time will be described, the signs of the graphs of faulty refrigeration devices will be described, indicating the cause of the malfunction. The authors indicate the parameters by which it is proposed to compare the obtained power graphs with the reference graphs obtained when testing reliably serviceable refrigeration devices. Based on the results of comparing certain values of the parameters characterizing the device it is proposed to judge the compliance of each individu-al refrigeration device with the standard. It also provides a description of the algorithm that will be used to determine the compliance of the refrigeration device with the established parameters of heat and power characteristics that determine its performance. The implementation of this algorithm will be carried out by writing an appropriate program for the programmable logic controller (PLC).
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Development of a DVB-S2X signal generator for modem equipment testing
Статья научная
This paper examines the specifics of ground-based experimental testing of modem equipment for satellite communication systems operating in highly elliptical orbit (HEO). We formulate the problem of lacking specialized test equipment for this testing process. Using software-defined radio technology, we develop a generalized block diagram of a DVB-S2X standard test signal generator that additionally implements simulation of signal retransmission by satellites operating in HEO. We develop a suite for application and specialized software of the signal generator, implementing traffic preparation, encapsulation, and synthesis of complex baseband signal samples on an FPGA in accordance with the DVB-S2X standard. We propose a generalized digital signal processing architecture that simulates distortions characteristic of signal propagation through a satellite transponder in a highly elliptical orbit. We implement a prototype signal generator based on the USRP X410 software-defined radio platform, operating across symbol rates ranging from less than 0.1 to 122.88 Msym/s. We present a generalized block diagram of the test bench used for experimental studies. We show practical results of FPGA resource utilization in the X410 radio device for implementing the developed specialized software, verification results of the generated signal-code structure, and performance test results of the prototype signal generator using a reference demodulator. The obtained results fully confirm the correct operation of the developed prototype signal generator. The developed prototype can be used as part of the test and verification equipment for modem hardware within the ground communication complex of the Express-RV system.
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Development of a methodology for testing SpaceWire network switches
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The paper presents the main points of the developed methodology for testing SpaceWire network switches. The main objectives of testing this equipment are outlined. A block diagram of the workplace is provided, as well as a list of equipment with its brief description for conducting tests. To conduct the tests, special software was developed, implemented in the form of a console user application. The methodology describes in detail each step of working with this application. This article describes the algorithms that are implemented when working with the application. These algorithms are presented in the form of flowcharts, as well as in the form of a text description. Two groups are distinguished among the algorithms: basic and advanced tests. For the first group, we can distinguish: a basic test - to check the principle of removing the header in accordance with the path addressing; a load test - to check the correct operation of the switch at high load of the switching matrix, as well as checking the deletion of incoming packets that do not contain addresses in their header to be sent to one of the switch ports; an exceptional situation test is used to check the correct operation of the switch when the receiving buffer is loaded with incoming data. For the second group, we can distinguish: the routing table test - to check the correctness of the processing by the switch of the rows recorded in the routing table; the broadcast test – to check the ability of the switch to send one data packet from several ports at the same time; the adaptive group routing test – to check the ability of the switch when selecting multiple ports for data transmission to send them from the port having the highest priority. All the indicated algorithms were tested on a radiation-resistant fault-tolerant ultra-large inte-grated circuit of a programmable master switch of the 3rd level. In conclusion, further plans for the devel-opment of the methodology are outlined.
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The article examines the role of information technology at industrial enterprises of the rocket and space industry, provides the results of the analysis of scientific sources to organize information support systems for making management decisions, an analysis of existing methods for constructing management account-ing at enterprises and methods of its automation. Conclusions are made about the insufficient elaboration of the studied solutions, both from the point of view of the logic of the organization of accounting, and from a technical point of view. The main tasks of the information support system, methods of forming effective management accounting and the goals of its implementation are determined. An approach to create an in-formation support system in the form of a built-in control database in the form of an OLAP solution is pro-posed, through which functional information systems are integrated, and detailed management accounting related to accounting and tax accounting is built into a single system in a single information space. The article describes the advantages of implementing the proposed system, which allows for a comprehensive retrospective and operational analysis of the current state of the processes oc-curring at the enterprise with a monetary value using SQL tools with a high degree of confidence in the data. The principles of creating elements of the information system for the subsequent effective plan-fact analysis and development of management decisions are discussed. A diagram of the organization of a sin-gle information space and a system that provides information support for enterprise management processes is given, the main information flows are considered. The logic of maintaining the process of forming a structured data warehouse is described, while automating the financial and economic part of the auto-mated control system based on the presented method of organizing data, which allows to link management, accounting and tax accounting with one source of relevant data, while creating an effective OLAP solution. An illustrative example of the organization of data in the form of linking the reflections of primary documents by means of a database using the proposed method, which provides the possibility of operational analysis of receivables and payables and the implementation of preliminary financial control-ling, is given. The research provides examples of user interfaces from the developed information support system based on the described methods of data organization. Conclusions are made about the effectiveness of the proposed solution.
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