No 2 (2023)
Articles
Ambiguous Results when Using Parallel Class Methods within the .NET Framework
Abstract
Parallel programming is a way of writing programs that can run in parallel on multiple processors or cores. This allows programs to process large amounts of data or perform more complex calculations in a reasonable amount of time than would be possible on a single processor. The advantages of parallel programming: increased performance, load sharing, processing large amounts of data, improved responsiveness, increased reliability. In general, parallel programming has many advantages that can help improve the performance and reliability of software systems, especially with the increasing complexity of computational tasks and data volumes. However, parallel programming can also have its own complexities related to synchronization management, data races, and other aspects that require additional attention and experience on the part of the programmer. When testing parallel programs, it is possible to get ambiguous results. For example, this can happen when we optimize concatenation of float- or double-type data by means of For or ForEach methods of the Parallel class. Such behavior of a program makes you doubt about the thread safety of the written code. Such a conclusion can be incorrect and premature. The article reveals a possible reason for ambiguity of the results received by a parallel program and offers a concise solution of the question.
Software systems and computational methods. 2023;(2):1-14
1-14
Principles of developing a limited-queue mass service system on the .NET platform
Abstract
The paper is the result of the thorough research aimed at studying the principles of creation, modeling and practical use of queue-limited mass service systems (MSS) based on the .NET technology platform and implemented using the C# programming language. In the course of the paper, special attention is paid to both single-channel and multi-channel systems. In the introductory part of the article the fundamental concepts of the theory of mass service are considered. The basic characteristics of systems, such as fixed queue length systems, single-channel and multi-channel systems with probability of service failure, systems with unlimited and limited wait times, closed systems, and multi-channel systems with channel-to-channel interaction, are discussed. Detailed examples of C# code are presented to illustrate the class structures used to model both single-channel and multi-channel MSS. Specific scenarios for the use of the presented structures within the framework of MSS modeling are considered. The paper highlights the practical application of mass service systems in solving real-world problems. Using examples from banking and traffic management in telecommunications, it is demonstrated how MSS can contribute to optimizing waiting times and efficient resource management. Prospects for further research in the field of mass service systems are suggested. Given the importance of MSS in various industries such as banking, telecommunications, logistics and many others, the high relevance of the topic is due to the need to find new approaches and methods to improve the efficiency and optimization of these systems. In general, the article is a valuable research material for specialists involved in modeling and practical application of mass service systems.
Software systems and computational methods. 2023;(2):15-28
15-28
Development of an automated system for testing a cloud service for deploying virtual machines using modern monitoring tools
Abstract
The object of this study is a service for managing virtual machines in a cloud environment. When developing and operating such a service, it becomes necessary to assess its availability and reliability for compliance with the selected quality level that the client can count on. This paper presents a developed system that allows testing the availability of a cloud service for managing virtual machines. The method of integration with the existing monitoring system at the enterprise using open source software in order to reduce the cost of development and operation is considered. A test case for deploying and removing a virtual machine using a graphical user interface has been developed and implemented, and triggering criteria have been defined. The requirements for the architecture and implementation of the system based on the production statistics of the virtual machine creation service using the Prometheus monitoring system are collected and analyzed. The novelty of the research lies in the development of a new method of testing a cloud service for managing virtual machines in order to increase its reliability and availability. Based on this method, a system for testing virtual machines is described and implemented, as well as a method for integration into the monitoring system of the Intel cloud service. During the operation of cloud environments with the help of this system, problem areas were identified in the architecture of the virtual machine creation service, which made it possible to optimize the system operation in a timely manner. The described method is an effective way to test cloud services, and can also be used to analyze and improve reliability and availability.
Software systems and computational methods. 2023;(2):29-39
29-39
Development of the security and fire system training stand for student training
Abstract
The article is devoted to the organization of the educational process using a specialized laboratory stand of security and fire systems. The main purpose of the paper is to form professional competencies of students in the field of security and safety systems. The paper describes in detail the structure and components of the laboratory stand, emphasizing the importance of its key elements - the control panel "Astra-812 Pro" and a variety of detectors. This allows students to practically apply theoretical knowledge, studying the functioning and interaction of various components of the security and fire system. The article also presents schemes of connection of detectors to the expander, allowing students to more deeply understand the technical side of the process. The steps of the bench training are disclosed to support step-by-step, sequential learning. The study emphasizes the effectiveness of the proposed learning system, which involves direct student interaction with hands-on equipment. The findings confirm the significance of using such training stands in modern higher professional education, emphasizing their contribution to the formation of the necessary professional competencies in future specialists in the field of safety and security. Scientific novelty of the work consists in the development and application of a specialized training stand for teaching students to work with security and fire systems. This allows students to get direct experience of interaction with the equipment, deepen their understanding of the technical aspects of the systems operation and improve their practical skills. The work also contributes to research on educational approaches in the field of safety and security by proposing an effective teaching methodology through the use of a laboratory bench. This provides a platform for further research and development in this area that can broaden and deepen the educational opportunities in the field.
Software systems and computational methods. 2023;(2):40-48
40-48
Eye-tracking detection of the area of interest in data visualization
Abstract
This study examines the features of forming in data visualization. To do this, the authors hypothesize that there are special areas of interest on the charts. The user pays attention to them in order to decode data encrypted with graphics. The presence of such areas, and in some cases, points, are intuitively determined during the formation of the design rules of information graphics. To verify them, the study used the eye-tracking method and the cluster analysis method. The application of interdisciplinary principles and rules of infographics design has been studied on the example of horizontal and vertical bar charts, pie, pictorial and flow charts. The result of experiments with various types of charts showed the presence of additional areas of interest not previously indicated by data visualization specialists. This makes it possible to clarify the features of graphic forms and the formation of diagrams, allows you to verify the use of design rules formulated by the efforts of domestic and foreign specialists in the late XIX — early XX centuries. Such verification can be done using a methodology that includes statistical methods and the tracking method, which allows us to take into account the valuable experience of the past in modern information design. The presented procedure can be extended to other types of charts, diagrams and thematic maps, and have practical application in the analysis of big data visualization.
Software systems and computational methods. 2023;(2):49-62
49-62