ISSN 0236-235X (P)
ISSN 2311-2735 (E)

Journal influence

Higher Attestation Commission (VAK) - К1 quartile
Russian Science Citation Index (RSCI)

Bookmark

Next issue

2
Publication date:
16 June 2024

Articles of journal № 4 at 2018 year.

Order result by:
Public date | Title | Authors

21. A modified algorithm of random multiple access with successive interference cancellation [№4 за 2018 год]
Author: S.A. Zhezhera
Visitors: 7485
The subject of the study is the analysis of the throughput and reliability of wireless networks in multiple random access systems. The article investigates the possibility of increasing the efficiency of random multiple access with interference mitigation. In a multiple-access system, data transmission is based on the competition of stations for the overall transmission medium. Each node that does not have a debt passes a packet while risking to fall into random conflicts. The aim of the article is a new solution for the joint operation of an algorithm with an interference mitigation procedure when the base station is able to subtract a subscriber signal from a previously received signal in order to recover a residual signal to improve the reliability of wireless networks with pulsed traffic. The modified algorithm is based on the idea of searching in the set of received signals of an orthogonal subset that allows simultaneously extracting all the set of conflicting signals. The algorithm uses a full search and therefore has considerable computational complexity. Research results revealed that the process of conflict resolution is accelerating when using the procedure for canceling interference. In order to do this, subscriber signals should be stored in special additional memory cells. When the multiple access algorithm is modified into an outgoing signal from each subscriber, the service information of the previous attempts to transmit the signal is added. The exclusive right to use the procedure to cancel interference can reduce the probability of conflicts and thus increase the quality of data transmission. The paper proposes to use a modified algorithm from the ALOHA family with the possibility of canceling interference in networks using the Poisson input stream.

22. Application development for preparing meshes using snappyHexMesh of OpenFOAM [№4 за 2018 год]
Authors: Chitalov, D.I., S.T. Kalashnikov
Visitors: 8569
The paper describes an application with a graphical user interface for preparing computational meshes that contain hexahedra and split-hexahedra from triangulated surface geometries using the OpenFOAM software environment, and the application development process. The paper presents the existing paid and open software tools used to simplify the problem of preparing such computational meshes. The authors determine their limitations and relevance of the indicated problem and the necessity of developing a new application for preparing meshes for OpenFOAM SE. The authors have made a list of tasks to implement the development. They have studied the operating principle of OpenFOAM SE utility responsible for the mentioned type of CM generation. The determined list of necessary tools for program development includes a programming language of application logic, a library that provides implementation of interface elements, and the development environment. The authors indicate the software required to use the developed application. There are diagrams that describe the application structure, the algorithm of user's work with application. The paper also determines some difficulties in algorithm implementation and program logic and proposes the ways to solve them. The application has been tested on the training task included in of OpenFOAM SE. The authors summarize the results of the conducted research, evaluate the practical importance of the conducted research work and the created software application, possible prospects of the research. The paper provides a web resource that contains the developed application, which is freely available, for testing and practical using.

23. Development of a software tool for studying electromagnetic wave diffraction on nonlinear elements [№4 за 2018 год]
Author: V.N. Pichugin
Visitors: 4245
Nowadays the actual area of scientific research is nonlinear radar. Non-linear sensors for detecting the objects they mark and identifying them are in demand. Such nonlinear sensors-markers are installed on transported objects and transmit up to 1000 bits of information during identification. The object of the study is the diffraction of electromagnetic waves in nonlinear emitters of radio devices (sensors) operating in multi-wave mode. The research included modeling of arising electrodynamic effects. The goal is to develop a software tool and simulate diffraction characteristics of electromagnetic waves on a lattice of nonlinear elements. The software simulator is developed in the RAD Studio integrated environment using the OpenGL library on the Windows platform. All simulator properties that might be changed are used at the run-time mode, i.e. the front-end form and visual components are created during the compile process. The software simulator is designed to build a model of spectral characteristics in the long- and short-wave parts of the wave spectrum. It is also applicable when studying the characteristics of scattering from perfectly reflecting and semi-transparent obstacles in the free space or on extended surfaces. Similar methods of remote study of extended surfaces are based on the signal analysis that are formed as a result of reflection or electromagnetic waves emission by the pathways. They allow judging their relief, characteristics and type of different locations, sizes of different objects, etc. The main result of the study is the developed software methods for analyzing of non-linear emitters gratings in multi-wave reception, as well as software methods for calculating the diffraction characteristics at high frequencies taking into account the inhomogeneity of electromagnetic fields.

24. A corpus manager system: corpus data architecture and models [№4 за 2018 год]
Authors: D.R. Mukhamedshin, D.Sh. Sulejmanov
Visitors: 8134
Modern corpus data management systems allow solving a wide range of computer linguistics problems. Such systems are often based on ready-made solutions, which causes the problems with search query execution speed (data extraction), flexibility, scalability and extensibility of the system. This article considers the architecture of the corpus manager sys-tem for the Tatar Corpus. It also proposes a corpus data model that solves a number of problems of the existing corpus manager systems. The paper describes in detail the architecture of the software part of the system, which allows quick developing of additional modules and integrating third-party applications into the system. The corpus data model presented in the article is designed to solve quick search tasks using wordforms and lemmas (direct search), as well as morphological properties (reverse search). The developed model also allows phrasal and syntactic search, thus providing a solution for tasks related to more complex data extraction. The authors performed experiments in order to find the most optimal set of data storage technologies that allows solving the required problems and has the capability to expand the system functionality in the future. The paper presents the results of experiments, including the results of testing the performance of various CAD systems and data storages. The search module of the corpus manager system of the Tatar language corpus includes the described system architecture and the corpus data model. It shows a significant increase in the execution speed of search queries in comparison with similar modules in other systems.

25. Comparative analysis of spinlock realizations [№4 за 2018 год]
Authors: D.S. Tarakanov, Kosyakov M.S.
Visitors: 4799
The paper considers the problem of performance of multithreaded applications using spinlocks to synchronize access to a critical section. There is a detailed description of this mechanism, indicating potential bottlenecks. There is also an analysis of the existing spinlock implementations (such as POSIX spinlock, ticket spinlock and MCS spinlock) with a de-tailed explanation of their internal structure. In order to evaluate the effectiveness, the authors introduce two characteristics as follows: application agility (time in processor cycles) and the fulfillment of a fairness condition (quantified). The described spinlocks have been prepared and optimized to compare these implementations of spinlocks using a multi-core processor with shared last level cache. In addition, a test application is developed that allows varying the number of threads and the payload in the critical section and outside. The paper contains diagrams and graphs for the values of the introduced charachteristics. Based on the data obtained, characteristic problems (insufficient scalability, non-fulfillment of the fairness condition) for POSIX-spinlock and ticket spinlock are revealed, which negatively affect the performance of applications using these synchronization primitives. An analysis of the causes of these problems shows that the use of POSIX-spinlock and ticket spinlock leads to the need for permanent cache synchronization. Additionally, it is shown that POSIX-spinlock is not fair, and MCS-spinlock might potentially be inefficient with a small number of threads. The obtained results might be used both for further research of synchronization primitives associated with other implementations of the MCS-mechanism or non-blocking algorithms and be considered when choosing a spinlock to use in a real application.

26. Support tools for modeling logical rules in the RVML notation [№4 за 2018 год]
Authors: Dorodnykh N.O., Yurin A.Yu., Korshunov S.A.
Visitors: 6022
Nowadays there is a wide range of different means and methods of knowledge representation and processing. At the same time, a rule-based model is still one of the most common and popular formalisms of knowledge representation for the development of expert systems for various purposes. In turn, the effective application of languages for rule-based knowledge base engineering requires the use and creation of specialized toolkits that provide the visualization of this process. The use of specialized notations, which extend existing ones (UML in particular) is promising in the field of visualization of rule base engineering. The Rule Visual Modeling Language (RVML) is an example of such UML extension. The paper describes the main elements of RVML and software that supports it. In particular, it considers the webcentric Web RVML Editor. This editor supports RVML and is designed for end-users who are non-programmers. It also provides integration with external specialized software that is: the Knowledge Base Development System to access converting modules and Personal Knowledge Base Designer to test knowledge bases. The paper describes the Web RVML Editor architecture, its main functions and GUI. The paper also presents the Tiny RVML Editor that is desktop software. It is a prototype of the Web RVML Editor and it duplicates it functionally. The described software provide multi-platform support for visual engineering of logical rules in RVML notation and use the common approach and principles of GUI organization.

27. Structuring and qualitative consideration of a audio stream in a speech synthesis and analysis system [№4 за 2018 год]
Authors: N.E. Balakirev, H.D. Nguyen, M.A. Malkov, M.M. Fadeev
Visitors: 5565
Many approaches to speech recognition do not exclude new views on the recognition process and implementation. The paper focuses on presenting the idea of a new approach, although many practical results have already been obtained on its basis. It is practical results that led to a revision of the basic concepts of structuring a signal sound flow and further rethinking of the toolkit, which is based on a traditional oscillograph. The most important part of a new model is a structural matrix. Such introduction is justified on the example of processing one phoneme. Structural matrices make it possible to obtain the information content of a sound stream at different levels and with different recognition purposes: recognizing a phoneme, the voice of a particular person and speech tonality, including the tonality of the Southeast Asia phonemes. As for the toolkit, an important step in visual representation, which remained unchanged externally, was the possibility of unlimited scaling and using GPU for such implementation. However, the main innovation is that the source material are the structures representing a special kind of model representation and demonstrating the asserted idea and the notion of a qualitative representation of an input signal flow. Systematization of the flow through the structure optimized the process of opening the content of constituent elements (primarily speech). However, it complicated processing to obtain the required material. The toolkit involves both sides of work on the content of speech: analysis and synthesis. Hence, there are two processing directions: formation of structure models from a digitized signal and inverse transformation of such structures into an audio stream.

28. A translator of a tactical task to a Petri net for a group of unmanned ground vehicles [№4 за 2018 год]
Authors: A.A. Tachkov, A.V. Kozov, S.E. Pankov
Visitors: 7081
This paper represents analytics of main existing approaches to forming a tactical task for a group of unmanned military robotic vehicles. The selected approach uses an electronic map as a graphic basis to form a task using military symbols. The paper shows that operator's decision might be represented as an oriented multigraph with finite numbers of vertices and arcs. Within this representation, the developed task translator allows converting an initial operator’s decision (defined with military symbols) into an equivalent Petri net to control a group of military robotic vehicles. The paper defines target formalities for translator design, structure, basic blocks and standard translation rules. The developed translator uses a geoinformation system and a military symbol classifier for coding group actions of robotic systems. The software for the translator is in C++ as a DLL library for Panorama geoinformational system. There is also a class diagram. The paper presents an example to show how the translator works. There is a typical task for a group of robotic vehicles. It includes division into sub-groups, parallel moving onto firing line, reallocation of complexes among subgroups, reaching the objective. The initial operator's decision is represented by military symbols. The paper also shows an equivalent Petri net. The proposed translator with an electronic map technology allows automating tactical task formation for a group of robotic military unmanned vehicles.

29. Electronic forms for computer simulators [№4 за 2018 год]
Authors: A.V. Vus, Ilin V.А.
Visitors: 6147
The paper proposes to use an electronic form for automating the main processes of form transaction for a computer simulator during its maintenance and developing proposals for its further use based on the collected operation data analysis. An electronic form is an electronic equivalent of a standard form. The paper presents a general structure of an electronic form for a computer simulator. It is proposed to store three types of information in an electronic form database. They are: permanent data, operational data and reference information. The paper also describes an operation algorithm for the electronic form. In order to reduce manual operations for collecting and processing data on a simulator state and to eliminate the the human factor affecting the quality of technical documentation, it is proposed to include an automatic data collection and processing module into the electronic form. This module is a client-server system installed on all computer simulator workstations. It allows automating the process of monitoring and analyzing a computer simulator technical state. For the first time, the paper proposes an algorithm of an automatic data collection and processing module. It includes the algorithm of a module client collecting operational data and module servers accumulating and analyzing the obtained data. The application of the proposed module for automatic data collection and processing will allow receiving recommendations on further use of a computer simulator based on the collected information. There is also a generalized algorithm for an electronic form operating with an automatic data collection and processing module. The proposed algorithm of the electronic form will significantly reduce the load on computer simulator staff, therefore, it will allow focusing on preparing a simulator for classes and conducting classes.

← Preview | 1 | 2 | 3