Software & Systems

Articles of journal № 4 at 2016 year.

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21. Parallel calculations as a way to increase the efficiency of computing aerodynamic problem solutions [№4 за 2016 год]
Authors: S.A. Burenkov, O.Yu. Shamayeva
Visitors: 7404
The article proposes software to increase the efficiency of solving aerodynamic problems in high-performance cluster systems. The software is implemented on the basis of the proposed parallel-sequential algorithm for solving sparse systems of linear algebraic equations of high dimensionality using the method of generalized minimal residual. The article provides a theoretical estimate of the developed algorithm complexity, as well as a comparison of the results of theoretical estimates and computational experiment results. The software is implemented for a distributed memory computation model and is used to solve a model problem of an aerodynamic flow of a profile with an air flow. There are the results of a computational experiment on calculating the density and pressure of the blowing profile air flow in the high-performance cluster, which illustrate the effect of using a parallel program. The article analyzes the characteristics of model problem parallel solution acceleration, which allow determining a threshold of dimension of systems equations. Below the threshold the organization of parallel computing adversely effects on the efficiency of computing resources. The paper also studies the effect of a sparse coefficient matrix degree on parallel implementation acceleration. The given results can be applied not only on computational hydrodynamics and gas dynamics, but also energetics, biology, chemistry, pharmacology, astrophysics, and others.

22. Statement of the research problem of the diffusion transition across the slag-metal border in a column reactor and its solution algorithm [№4 за 2016 год]
Authors: Sechenov P.A., V.P. Tsymbal, Olennikov A.A.
Visitors: 9826
The subject of the research is the problems of the diffusion transition across a slag-metal border and metal particles decarbonization when passing through a slag layer. The authors give a mathematical problem statement through the slag-metal border problems within a simulation model of a jet emulsion reactor gravity separator. The article compares the object-oriented programming languages (Delphi, Visual C #, ActionScript 3.0). It allocates simulation model targets. There is a comparative analysis of simulation models created over the past 10 years. Dimension space is taken as a comparison test (one-, two- and three-dimensional). The authors give the scheme of interaction between simulation model classes and the main unit. Particular focus is on the classes: “slag at the botto”, “metal at the bottom”, calculations and the main unit since they implement the assigned task. The paper describes the properties of the slag class (percentages of slag components’ weight and the variable for interaction with the settlement class) and methods (initialization of the class variable, increment function and slag composition change). The calculating class contains the functions determining FeO balanced content and the recovery rate on the slag-metal border. This article shows an algorithm of slag iron decarburization and its interaction with other program classes. To implement the task the authors chose the simulation method (Monte-Carlo). It allows constructing an algorithm with the knowledge of object mechanisms, based on random playing. As a result of the second scheme (metal particles decarbonization when passing through a slag layer) the authors conducted some experiments on the simulation model with the same initial conditions and sufficient modeling time (10 minutes). The simulation studies showed that when implementing only the first mechanism carbon content in the final product is 4 %, and when implementing two above-mentioned circuits it is 3,5 %. It shows the possibility of more flexible management of a decarburization process.

23. Single screw extruder engineering with artificial intelligence elements [№4 за 2016 год]
Authors: Zubkova, T.M., N.А. Mustyukov, М.А. Tokareva
Visitors: 8453
Market fierce competition makes the extrusion equipment manufacturers offer advanced and new technologies for a wide range of products every year. Therefore, production must be flexible, adjusting to different configurations of products, raw materials and types of productivity depending on current needs of the market. The complexity of the extrusion process does not allow figuring it out by conventional methods without using automation design (SAPR). The reduction of engineering process complexity of single screw extruders based on flexible SAPR organization is a current issue. The study developed a method of building SAPR screw extruders based on the integration and configuration of its subsystems. The created software system is the SAPR core and includes the integration of the components (a third-party CAD/CAE-systems, designed processes mathematical models, user interface components, engineering tools), data management, native software modules connection, designed to analyze the process of extrusion and optimization of technological and geometrical parameters of screw extruders. SAPR framework for screw extruders allows engineering the extruders; automating the adjustment of geometrical parameters and data preparation for analysing the structure; to carry out a simulation extrusion process; to optimize design and technological regimes; to manage extruder design data, extrusion process and simulation results. The developed software system helped to creat a new press extruder and improve the homogenization of the material being processed. The constructions are protected by patents of the Russian Federation. The proposed method of geometrical parameters optimization of the extruder-based adaptive methods enhances the search for new and improvement of existing designs. The article reflects the results of the grant № 14-08-97031 performed with the financial support of the Government of the Orenburg Region and Russian Fundamental Research Fund.

24. KLEE for automatic testing programs in C/C++ [№4 за 2016 год]
Authors: A.G. Zykov, I.V. Kochetkov, V.I. Polyakov
Visitors: 8809
The article considers the problems of automation of software functional error testing. This kind of bugs is extremely difficult to find and reproduce without code execution. This problem is relevant due to ever-growing software complexity. It leads to increasing duration, complexity and cost of software testing and verification. The purpose of the research is to analyze symbolic execution (evaluation) system basic features and their application in finding functional bugs and software testing in general. In particular, the article discusses the KLEE system in detail. This system is a symbolic virtual machine with environment emulation that executes parallel symbolic processes. It is based on analyzing a program LLVM byte-code. The article deals with KLEE architecture, components set, operation principles, features and some other aspects. Novelty of this research is in the consideration of alternative methods of using symbolic execution tools. They are developed based on using their basic features. There is testing with reference program, problem solving (for example, finding a way in a labyrinth) and restoring an algorithm flowchart. The article presents KLEE testing statistics (code coverage, bugs count, etc.) of COREUTILS 6.11 package, where there were found several serious bugs that had been missing for over ten years.

25. APS for multinational companies: problems and prospects of development [№4 за 2016 год]
Authors: A.A. Sukhobokov, A.V. Sukhobokov, D.S. Lakhvich, I.V. Tikhonov
Visitors: 10464
The article presents the common architecture of the Advanced Planning System (APS). It shows that mathematical models and methods of linear programming, which are now applied for the master planning, are not able to solve a key problem of profit optimization for multinational companies. The paper also considers the evolution of mathematic models and methods used for optimizing profit after the tax in multinational companies. In current situation in order to optimize the supply chain of big multinational companies it is necessary to solve a problem of great dimensionality, because data matrices contain dozens of billions columns and lines and have bilinear and trilinear constraints. Approaches to parallelization of numeral algorithms for this problem are also under consideration. The main stress is on a most prospective approach which uses Big Data platforms for solving great dimensionality problems. Hereafter, the article defines the additional functionality of a supply chain design module and a demand planning module, so that APS could be of use in multinational companies. The authors also define the additional functionality of financial supply chain management modules and of neighboring ERPsystem’s controlling modules. It is shown that prospective APS for multinational companies should be developed on the basis of a complex of two integrated technology platforms: the In-Memory platform and the Big Data platform. The functional architecture of APS for multinational companies is presented in the context of the general enterprise management system as a whole. In addition, the architecture of APS master planning module is detailed one level deeper. It solves optimization problems for one time period, as well as for a finite number of time periods.

26. Program system of structural and parametrical synthesis of an information security system [№4 за 2016 год]
Authors: Zhukov V.G., M.N. Zhukova, A.S. Timokhovich, D.S. Volkov
Visitors: 9753
The article is devoted to the solution of an important problem of structural and parametrical synthesis algorithm development for an information security system on the example of creating a protected automated system. This algorithm allows generating several possible options of an information security system considering requirements of state standards in the field of information security, standard and methodical documents of the Federal Service for Technical and Export Control of Russia and the Federal Security Service of Russia. Besides, each architecture of an information security system assumes using rather large number of information security means. It complicates the task because of various options of information security system created architecture implementation. The paper considers only certified means of information security for implementation within the constructed architecture of information security system. Such problem of optimization has a set of features and restrictions. Classical optimization methods in this case aren't applicable. The analysis of various schemes of application of an optimization genetic algorithm which has proved itself when solving similar problems of optimization. However, application of a classical genetic algorithm is impossible because of features of requirements of standard and methodical documents, regulators in the information security area, structures of information security system and a component in the form of information protection means. A set of algorithm modifications is carried out. They allow applying the developed algorithm when solving real practical tasks. The developed algorithm with modifications is implemented as software. Software operation is tested at various versions of requirements to the created information security system. The efficiency of structural and parametrical synthesis of an information security system when using the developed software is 84 % at average.

27. Software modeling of stochastic temperature fields in stf-electron mod technical systems [№4 за 2016 год]
Author: Kandalov P.I.
Visitors: 8561
The article presents the software package “STF-ElectronMod” to simulate a steady-state stochastic 3D temperature fields in technical systems Experience has shown that the actual temperature fields of technical systems have uncertainty interval nature. This is due to the interval factors determining the thermal regime of the technical system. These factors include: the design parameters of technical sys-tems with statistical techno logical manufacture spread; factors arising in the operation of technical sys-tems ( power consumption, heat flows, internal environment parameters); environmental factors (temperature, medium, refrigerant, flows velocity, etc.). However, now modeling of temperature fields of technical systems is being conducted under the assumption of determinacy. This means that all thermal condition parameters are considered accurately known This article describes a structure of the designed software system STF-ElectronMod for modelling of interval stochastic temperature fields in technical systems under uncertainty of input determining data. The method and algorithm are based on the author's developments according to a matrix-topological method, the software complex three-dimensional deterministic modeling of temperature fields of technical systems, as well as Monte-Carlo method. The application of the method and algorithm for modeling interval stochastic temperature fields is considered on the example of a complex electronic system.

28. Semantic analysis and methods of text meaning representation in computer linguistics [№4 за 2016 год]
Author: Batura T.V.
Visitors: 24232
The paper is devoted to the problems of semantic analysis of texts. The article discusses different methods, such as dependency diagrams, semantic network, approaches based on lexical functions and thematic classes, frame, ontological and logical models of knowledge representation. At the moment, there are many methods of representing sentence meaning. Creating new methods of semantic analysis is significant in solving many problems of computational linguistics such as machine translation, automatic summarization, text classification and others. Development of new tools for semantic analysis is equally important. Despite the fact that some of the scientific and technical ideas in natural language processing are evolved, many problems of semantic analysis remain unsolved. Most of researchers came to the conclusion that the dictionary for semantic analysis has to operate meanings and, therefore, describe the properties and relationships between concepts, rather than individual words. But there is a question: how to organize and represent information in these dictionaries to search it fast and conveniently, and in addition, take into account the changes in the natural language (the disappearance of old and the emergence of new concepts). This paper attempts to answer this and other questions. The article undertakes an attempt to systematize known achievements in the field of a semantic analysis, and in any measure to find the answer to this and other questions.

29. Scientific and technical computing system mathcad to design and analyze differentiated teaching load models [№4 за 2016 год]
Author: E.Yu. Shakhova
Visitors: 8142
Nowadays, many universities have processing of local regulations governing the work of academic teaching staff. There is a strong requirement to differentiate teaching load upper limits according to academic teaching staff positions. The paper considers and analyzes linear and non-linear models of standard teaching load distribution. The methods used are the following: least-square approximation by a linear function and third-degree polynomial, spline interpolation. The simulation was performed using MathCAD. The authors defined the most effective models for different population structure of professors. The criterion of efficiency is the smallest amount of excess teaching load. Evaluating of the constructed linear and nonlinear models’ effectiveness was based on three options of an academic teaching staff population structure in a university (institute) structural unit with high, medium and threshold levels of professors and associate professors in a total number. The obtained results show that the linear differentiation of teaching load upper limits is not always the best solution. Linear models in this study proved to be most effective only in case of the institute model with a high level of professors and associate professors in the total number of teaching staff. The most effective non-linear model for models with middle and threshold levels of academic teaching staff is a spline interpolation model (a curve that is cubic spline with parabolic endpoints). The paper also shows that for all the above mentioned differentiation models with a high level professors and associate professors in the total number of institute teaching staff the minimum excess teaching load exceeds the maximum excess teaching load for the institutions with a threshold and average level.

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