Software & Systems

Journal articles №3 2009

1. A web-based content generation system for a common digital space of scientific knowledge [№3 за 2020 год]
Authors: S.A. Vlasova (svlasova@jscc.ru) - Joint Supercomputer Center of the Russian Academy of Sciences – JSCC (Leader Researcher), Ph.D; N.E. Kalenov (nkalenov@jscc.ru) - Joint Supercomputer Center of the Russian Academy of Sciences – JSCC (Professor, Chief Researcher), Ph.D; A.N. Sotnikov (asotnikov@iscc.ru) - Joint Supercomputer Center of RAS (Professor), Ph.D;
Abstract: The paper discusses the web-based software package "Expertise", designed for expert evaluation of various types of objects to be included in the common digital space of scientific knowledge. Electronic publications, catalogues of library collections, databases, and information systems related to a specific scientific area, and other types of resources can be evaluated as objects. The assessment of objects ex-ercises during the session, which is the examination process, characterized by a given time period and a specific set of experts and objects. The software package consists of two modules: administrative and user-defined, and supports ex-pert and object databases. The administrative complex provides system setting for a specific session (creating metadata pro-files of experts and objects, rating tables, and the text of emails sent automatically to experts); entering and editing attributes of experts and objects in accordance with the established metadata profiles; viewing ratings assigned to objects; forming of rating lists of evaluated objects. As for the user-defined block, it focuses on the work of authorized experts. The expert evaluates an object by selecting one assessment from the normalized table. Each assessment consists of a pair of el-ements – a verbal expression and a corresponding numeric one. The user block interface allows to each expert to change the assessment previously assigned to the object, if necessary. The paper provides a detailed description of the “Expertise” complex functionality and its working technology illustrated by specific examples. The software package was tested in 2019 at two all-Russian competitions – for the best scientific monograph and for the best student qualification work. There were several hundred works at the competitions, and several dozen experts from different re-gions of the country participated in their evaluation.
Keywords: content formation, selection of information resources, digital libraries, the software, web technologies, information systems, expert assessments, digital space of scientific knowledge
Visitors: 452

2. Parallel processes and programs: models, languages, implementation in systems [№3 за 2020 год]
Authors: Kutepov V.P. (vkutepov@appmat.ru) - National Research University “MPEI”, Ph.D; A.A. Efanov (1134togo@gmail.com) - National Research University "Moscow Power Engineering Institute" (Postgraduate Student);
Abstract: The authors propose models and languages of parallel processes and programs, which have wider pos-sibilities for describing parallelism in comparison with well-known models and languages created for this purpose. The concept of an actor, the execution of acts, and the interaction of actors in the performance of a process are the basic elements of a process description. The general form of defining a process is a set of recursive equations, the right parts of which are groups of actors, which interact during the process execution. The graphic and textual form of the description of processes and the principle of initializing the execution of an act by the readiness of the signals (data) arriving at the inputs of the corresponding actor from the actors influencing it creates the necessary conditions for an effective description of the processes, their analysis, modification, and parallel execution. The interpretation of process actors as procedures provides a direct transition from the process language to the high-level language of modular multi-flow parallel programming. The paper considers the main implementation problems of the proposed languages on computer sys-tems: the unambiguous naming of the acts generated during the interaction of the process, the organiza-tion of process control on computer systems. It is known that classical algebraic models of processes belong to R. Milner and C. Hoar. In this pa-per, we consider a more general model and language of processes, which, on the one hand, makes it possible to describe groups of interacting processes when the general process is defined in the form of a system of process equations. On the other hand, a dynamically generated structural description of cause-and-effect relationships between process actors in groups and the use of an actor’s activation mechanism upon receipt of the necessary signals (data) to its respective inputs provide, without limita-tion, the implementation of parallelism and asynchrony when performing process acts. The use of vari-ables in the system of equations describing the process creates the conditions for the dynamic genera-tion of process groups. The model described in the article is the basis for creating a parallel programming language imple-mented on computer systems.
Keywords: actor model, implementation of parallel processes, computer systems, parallel programming, parallel processes
Visitors: 372

3. Design and programming features when creating information systems [№3 за 2020 год]
Authors: R.D. Gutgarts (gutgarc@gmail.com) - Irkutsk National Research Technical University (Professor), Ph.D;
Abstract: In the market of functional software designed to automate various problems and management levels at enterprises and organizations, a large number of ready-made design solutions are presented. Such ap-plications, as a rule, are positioned as typical ones and provide adaptation to specific conditions at the automation object by adjusting special parameters and (or) a relatively small amount of additional pro-gramming. However, the number of economic entities is large. All of them differ in production capacities, product range, and other characteristics. In a market economy, each of them is interested in maintaining and developing their competitive advantages. Therefore, it is not always possible to find a suitable au-tomated information system (IS) that satisfies all the necessary requirements. And then there is a need to create a system in accordance with an individual order. In such cases, its quality will completely de-pend on the correctness of the formulated requirements on the part of the customer and the profession-alism of the developer. The requirements are reduced to algorithms for solving problems, and the algorithms themselves are defined and agreed upon at the design stage of the information system. When programming, only cod-ing of algorithms is performed, i.e. recording them in the form of formal constructions in an algorithmic language suitable for execution on a computer. The paper shows the real dependence of the programming phase on the design phase since pro-gramming is always secondary to design. An exception is the technology used for rapid application de-velopment when an inextricable link is formed between the two stages and they are essentially com-bined into one. The importance of design is proved and some of its features are considered. To illustrate, examples of private design solutions are provided.
Keywords: software engineering, features of designing documents, features of the design stage, the life cycle of an information system, stages of creating information systems, information systems design
Visitors: 388

4. Data structures and the Quine–McCluskey method modification for minimizing normal forms [№3 за 2020 год]
Authors: Gdansky N.I. (al-kp@mail.ru) - Moscow Polytechnic University (Professor), Ph.D; A.A. Denisov (aadenisov88@gmail.com) - K.G. Razumovsky Moscow State University of Technology and Management (First Cossack University) (Postgraduate Student); Kulikova N.L. (kulikovanl@mpei.ru) - National Research University "Moscow Power Engineering Institute" (Associate Professor), Ph.D;
Abstract: Logical methods of analysis and synthesis of systems of various nature are usually based on the use of descriptions of their structures and processes in them in the form of Boolean functions, which are equivalently reduced to conjunctive normal forms to unify the representation. For initial systems and processes, as a rule, the main criterion for optimality is the minimum number of components that make up their components, which simplifies the structure, reduces cost and increases reliability, so for model conjunctive normal forms, the problem of minimizing them is of great practical importance. The algorithm’s efficiency that processes complex objects (including conjunctive normal forms) significantly depends on the main and auxiliary data structures used to represent these objects. There-fore, based on the analysis of existing structures, a new complex three-level data structure for repre-senting conjunctive normal forms has been developed. The lower level of the entire combined structure is the data structure for a single clause. Lists of clauses with the same number of letters form the middle level. An array of lists ordered by the lengths of their clauses sets the entire conjunctive normal form at the top level. The using lists, pointers to them and single elements, and the ordering of clauses by lengths make it possible to radically reduce operations for rewriting information and ordering it in the process of con-verting conjunctive normal forms. Based on the developed complex data structure, the authors developed a modification of the well–known Quine-McCluskey method used to reduce perfect normal forms. The combined use of the proposed data structure and the modified method makes it possible to sig-nificantly reduce the total number of operations while minimizing conjunctive normal forms compared to the basic version of the Quine–McCluskey method. This is achieved by reducing data re-processing, and by using special logical conditions, an addi-tional reduction is achieved in the total number of checks of letters in clauses when comparing them.
Keywords: clause, conjunctive normal form, data structures, quine-mccluskey method
Visitors: 346

5. Agent-based models, methods and tools for the development of compatible problem-solvers for intelligent systems [№3 за 2020 год]
Authors: V.V. Golenkov (golen@bsuir.by) - Belarusian State University of Informatics and Radioelectronics (BSUIR) (Professor), Ph.D; D.V. Shunkevich (shunkevichdv@gmail.com) - Belarusian State University of Informatics and Radioelectronics (BSUIR) (Assistant), Ph.D;
Abstract: The article is devoted to the development of agent-based models, methods, and tools for the develop-ment of compatible problem-solvers for intelligent systems that can solve complex problems. We con-sider the requirements for such solvers, a model of a problem solver that meets the requirements, as well as the methodology and development tool and modifying such solvers. The main problem considered in the paper is the problem of low consistency of the principles un-derlying the implementation of various models for solving problems. As a result, the simultaneous use of different models for solving problems in a single system when solving the same complex problem is substantially difficult, it is practically impossible to reuse technical solutions implemented in any sys-tem, in addition, there are practically no complex methods and tools for developing problem solvers capable of providing the solver development process at all stages. It is proposed to use a multi-agent approach as a basis for solving the problem of compatibility of problem solvers. The process of solving any problem is proposed to be divided into logically atomic actions, which will ensure compatibility and modifiability of the developed solvers. It is proposed to consider the solver as a hierarchical system consisting of several interconnected levels, which provides the ability of the independent design, debugging, and verification of components at different levels. The proposed models, methods, and tools were applied in the development of a number of proto-types of intelligent educational systems, as well as a prototype of a recipe production automation sys-tem.
Keywords: semantic technologies, ostis-system, problem solver, multiagents systems, intelligent agent, knowledge base
Visitors: 380

6. Application of transfer learning for semiotic models to the foraging problem with real robots [№3 за 2020 год]
Author: V.V. Vorobev (Vorobev_VV@nrcki.ru) - National Research Centre “Kurchatov Institute” (Deputy Head of Laboratory); M.A. Rovbo (rovboma@gmail.com) - National Research Centre “Kurchatov Insitute” (Research Engineer);
Abstract: The paper considers the problem of applying a transfer learning algorithm for agents with semiotic models of the world to the foraging task with real robots. The robot needs to collect randomly placed food items, which when collected appear in a new random place within the polygon. The mobile robot is controlled by an agent with a model of the world that describes sensor readings as predicates. The agent makes decisions based on a state-action value estimation table for Q-learning. The agent is pre-trained on a simplified model environment with discrete states in which actions are performed with a guaranteed deterministic outcome. In a real environment and its model, taking into account physics, actions can be performed incor-rectly due to a scheduler error, localization errors, and other problems, and the data analysis of sensor information gathered from the continuous world determines the environmental state. The authors show the implementability of the corresponding interfaces and portability of the con-cept from a simplified model environment both to its more complete model that takes into account physics and a real robot. The transfer learning application is successful, but the final performance of the agent is reduced (probably due to the incorrect assumption of the determinism of the world in a real environment) and the robot needs additional learning after the transfer. Gazebo was used as a simulator that takes physics into account while the real polygon was equipped with special markers and cameras for localization. The authors also used elements of augmented reality in the form of a virtual food module.
Keywords: semiotic models, transfer learning, foraging, robotics, reinforcement learning
Visitors: 347

7. Semantic models and the method of coordinated development of knowledge bases [№3 за 2020 год]
Authors: N.A. Gulyakina (guliakina@bsuir.by) - Belarusian State University of Informatics and Radioelectronics (BSUIR) (Associate Professor), Ph.D; I.T. Davydenko (davydenko@bsuir.by) - Belarussian State University Informatics and Radioelectronics (Associate Professor), Ph.D;
Abstract: The paper discusses an approach to easily modifiable hybrid knowledge bases creating based on se-mantic networks with basic set-theoretic interpretation. The paper proposes a semantic model of knowledge bases, including a set of top-level ontologies that ensure the compatibility of various types of knowledge. A distinctive feature of the proposed model is the use as a basic element of the model of not atomic elements of the semantic network, but signs of knowledge base fragments, called structures. The pro-posed model provides the consistency of different types of knowledge within the knowledge base, as well as the ability to knowledge bases structuring according to an arbitrary set of features. In addition, the paper describes a method for knowledge bases development based on this model, focused on the concerted development of a knowledge base by a distributed team of developers. A dis-tinctive feature of the method is its focus on the reuse of previously developed knowledge bases com-ponents of various complexity, as well as the presence of a formal ontology that describes the activities of the developers of knowledge bases in accordance with the method. The proposed method is implemented in the form of a system for the collective development of knowledge bases, which is embedded as a typical subsystem in each developed system and thus pro-vides the possibility of developing a knowledge base directly during its operation. The use of the proposed models, methods, and tools allows ensuring semantic compatibility of vari-ous fragments included in the knowledge base, as well as reducing the time spent on the development of knowledge bases.
Keywords: semantic network, knowledge base, knowledgebase structuring, coordinated development, intelligent system, reusable knowledge base components
Visitors: 360

8. Special features of SDN technology by Cisco Systems [№3 за 2020 год]
Authors: Yu.M. Lisetskiy (Iurii.Lisetskyi@snt.ua) - S&T Ukraine Company (Director General), Ph.D;
Abstract: The paper is devoted to software-defined networks currently dominating over traditional networks, which management and automation tools do not meet requirements of modern dynamic changes to con-figuration and scaling as well as virtualization. Distributed management concept where all the logic component of network operation is spread over network equipment is no more efficient enough. This is the reason for the emergence of a new concept and technology SDN (Software-defined Networking) – a network in which the management level is separated from the data transfer level and implemented pro-grammatically. Thus, in accordance with the SDN concept, all network management logic must be re-moved from network devices and implemented on a separate server – the SDN controller. The paper considers SDN technologies of Cisco Systems company, their development, and features. An important difference between these technologies is that they do not meet the basic principle of SDN, which is a separation of control and data planes. Such Cisco technologies as ACI and SD-Access preserve significant control plane functionality in the network devices and expand it with additional features. The basis for these technologies is the overlay networks or logical topology for the virtual connection of devices, which is built over arbitrary underlay topology. SD-WAN is a new Cisco WAN technology, which resulted from the application of SDN concept to distributed networks. Data plane of SD-WAN is the Internet overlay, working via the Internet. In ac-cordance with SDN concept, the SD-WAN, unlike SD-ACCESS, keeps control plane and data plane de-coupled and control plane functionality implemented in separate specialized devices. Having changed the ideology of implementation of enterprise networks Cisco has introduced DNA which is a new net-work concept enabling different services from the Cisco cloud.
Keywords: cloud, concept, principles, technology, topology, functionality, server, controller, virtualization, services, software-defined network
Visitors: 388

9. Support vector method modification development for solving the classification problem with domain restrictions [№3 за 2020 год]
Authors: Mikhailov I.S. (fr82@mail.ru) - National Research University “MPEI”, Ph.D; Zayar Aung (zayaraung53@gmail.com) - National Research University “Moscow Power Engineering Institute”, Applied Mathematics and Artificial Intelligence Department (Postgraduate Student); Ye Thu Aung (yethuaungg55@gmail.com) - National Research University “Moscow Power Engineering Institute”, Applied Mathematics and Artificial Intelligence Department (Postgraduate Student);
Abstract: One of the data mining methods for solving the classification problem is the support vector machine (SVM). The method’s main idea is to translate the source vectors into a higher-dimensional space using the kernel method to ensure the linear separability of classes and to find a separating hyperplane with the maximum margin between the hyperplane and the reference vectors in this space. Despite the high accuracy of the method, it also has disadvantages. These include the lack of a gen-eral approach to automatic kernel selection, as well as the high computational complexity of the meth-od. In this regard, the authors developed a modification of the support vector algorithm (FS-SVM algo-rithm) to solve the classification problem with restrictions on the problem domain. The authors formu-lated the classes "functional separability" restriction, imposed on the problem domain. It will allow ap-plying the FS-SVM algorithm. There is a theoretical study of these assumptions validity in the paper. The paper introduces formal definitions of "functional separability" based on the separating func-tion continuity and monotony and on the basis of the derivative of discriminant function. The authors show a "functional separability" concepts and classes convexity comparison. The proposed FS-SVM algorithm main blocks are considered in the paper: the search for support el-ements, the separating hypersurface points determination, the separating hypersurface construction as a piecewise-linear function in projection onto the coordinate axes under consideration. In further algo-rithm development, this function is proposed to be approximated by the Chebyshev polynomial to ob-tain a smooth curve. The paper presents as an example of a problem domain, in which the FS-SVM algorithm can be ap-plied, the oil-water-gas flow regimes classification problem, based on initial data obtained at the oil well mouth.
Keywords: machine learning, data intelligent analysis, support vector machine, modification of the support vector method, oil wells
Visitors: 3298

10. Experimental investigation of effectiveness of algorithms for minimizing BDD representations of Boolean function syst [№3 за 2020 год]
Authors: P.N. Bibilo (bibilo@newman.bas-net.by) - United Institute of Informatics Problems of the National Academy of Sciences of Belarus (UIIP NASB) (Professor, Head of Laboratory), Ph.D; Yu.Yu. Lankevich (yurafreedom18@gmail.com) - United Institute of Informatics Problems of the National Academy of Sciences of Belarus (UIIP NASB) (Junior Researche);
Abstract: The mathematical apparatus of BDD is used in various fields of science. In the computer-aided design field, BDD allowed to obtain significant success in a formal verification of algorithmic descriptions of digital circuits. Design systems of digital VLSI use programs of BDD minimization at the stage of tech-nologically independent optimization. Many articles consider optimization of BDD representations of systems of completely defined Boolean functions. Main attention was paid to finding an arrangement of variables for minimizing the BDD complexity. The variable arrangement is used to decompose the initial functions of the system and sub-functions (cofactors), which are obtained in the process of de-composition. The complexity of a BDD is the number of nodes in it. Each node of the BDD corresponds to a complete or reduced form of Shannon expansion. Domestic CAD and logic optimization systems use several programs for minimization of BDD rep-resentation of Boolean function systems that implement various algorithms. The purpose of this paper is to study the efficiency of these programs for synthesis of combinational circuits from library CMOS elements. After obtaining BDD minimized as for the number of graph nodes and defined as a set of in-terconnected formulas of Shannon expansion, the synthesis of a logic circuit is performed in the same design library of digital CMOS VLSI; the results are compared by square and delay. In many cases, it is possible to achieve additional reduction of logic description complexity by performing additional logic minimization based on Boolean nets. In this case, the optimization criterion is the number of nodes in the Boolean net, without considering inversion of Boolean variables. It is agreed with “the number of literals” criterion in optimization of multi-level logic circuits. The results of experiments on standard examples are presented.
Keywords: cmos, vlsi, vhdl, digital logic synthesis, binary decision diagram (bdd), disjunctive normal form, the system of boolean functions
Visitors: 356

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