Computer graphics, image processing and pattern recognition
Reference:
Ayusheev T.V., Bulychev R.N., Motoshkin P.V., Bubeev I.T.
Construction of a body with layered structure using Bézier boundary surfaces
// Software systems and computational methods.
2018. № 2.
P. 1-10.
DOI: 10.7256/2454-0714.2018.2.26291 URL: https://en.nbpublish.com/library_read_article.php?id=26291
Abstract:
The object of the study is a numerical simulation of the process of incremental forming of sheet metal in the manufacture of thin-walled parts on equipment with numerical program control. Particular attention is paid to the problem of constructing the surface of deformation of a sheet blank, under the influence of a working tool.The subject of the study is the solution of the problem of constructing a smooth three-parameter body with a layered structure using Bézier boundary surfaces from given interpolation nodes. The body is built on a frame, consisting of a set of curvilinear octagonal portions, in which the opposite boundaries have different parametric lengths.The method of investigation is a method for constructing a three-parameter body with a layered structure using Bezier boundary surfaces using the technology of parametric solid modeling. The novelty of the study is to develop a method for constructing a smooth three-parameter body of a layered structure on an arbitrary frame in the form of Bézier.Main conclusions. The use of the cubic Bézier function with parameterization along the length of the arc for describing the body of a multilayer structure provides additional advantages in controlling the shape and internal space of the body than the construction constructed using the generalized Hermite interpolation.Parametric three-dimensional bodies of this type can be effectively used in finite elements with irregular boundaries to avoid difficulties in constructing a model for such structures.
Keywords:
lamellar deformation, Bézier surface, Bézier curve, interpolation, lamellar body, body portion, three-parameter body, solid modeling, incremental forming, multilayer structure
Programming languages
Reference:
Savostin P.A., Efremova N.E.
Practical use of asynchronous programming in Python with Asyncio
// Software systems and computational methods.
2018. № 2.
P. 11-16.
DOI: 10.7256/2454-0714.2018.2.25851 URL: https://en.nbpublish.com/library_read_article.php?id=25851
Abstract:
The subject of the study is the study of the basic principles of asynchronous programming with the Asyncio package and their application for solving applied problems in Python. Since the Python interpreter uses the Global Interpreter Lock synchronization method, which limits the ability to parallelize programs in the given language and, as a result, does not allow achieving the greatest efficiency, the use of asynchronous programming technologies allows to significantly increase the speed of programs in this language, avoiding the mentioned limitations. The above described approach to creating programs is used in many tasks, for example: when creating a web server, client-server application, when extracting data from a resource by a web crawler. This paper is devoted to explaining the basic principles of working with the packageAsyncio in Python. Since the Russian-language literature on this package is often not enough to understand the basics of asynchronous programming in Python, this article gives examples of the use of this technology with explanations.
Keywords:
scraping, couroutines, parsing, web-crawling, asynchronous programming, asyncio library, python programming language, GIL, parallel computing, data extraction
Forms and methods of information security administration
Reference:
Drobotun E.B.
Method for estimating the cost of the life cycle of systems for protecting against computer attacks
// Software systems and computational methods.
2018. № 2.
P. 17-27.
DOI: 10.7256/2454-0714.2018.2.23086 URL: https://en.nbpublish.com/library_read_article.php?id=23086
Abstract:
The article deals with the economic aspects of building protection systems against computer attacks for information-computing and automated systems for various purposes. An objective assessment of the cost of the life cycle of systems to protect against computer attacks is one of the most important factors that determines the strategy for choosing a rational option for building defense systems. The subject of the study are the economic aspects of choosing options for building defense systems against computer attacks, as well as minimizing the financial costs of their creation and operation. The object - the system to protect against computer attacks. The methodology of this study is based on the use of an integrated approach to assessing the life cycle cost of protection systems as the costs included in the calculation year, including the share of the cost of the protection system, the costs of its implementation, operation during the use of the protection system, and the costs of its disposal at the end service life. Scientific novelty of the work is to create a real practical methodology that allows to evaluate all the components of one-time and current costs that are included in the cost of the life cycle of systems to protect against computer attacks. The offered technique allows to carry out an estimation of cost of a life cycle of several alternative variants of construction of system of protection against computer attacks and to make a choice of admissible on cost variants of construction of system of protection.
Keywords:
operating costs, total cost of ownership, cost estimation, current expenses, non-recurrent costs, life cycle cost, information security, protection system, computer attacks, information-computing systems
Quality aspects and improving the margin of reliability of software systems
Reference:
Mikheev I.V., Vishtak O.V., Kondratov D.V.
System of quantitative characteristics of software quality assessment
// Software systems and computational methods.
2018. № 2.
P. 28-35.
DOI: 10.7256/2454-0714.2018.2.25981 URL: https://en.nbpublish.com/library_read_article.php?id=25981
Abstract:
The subject of the study is the process of teaching programming. Information technologies are in close integration with various spheres of human activity. The peculiarities of information technologies include rapid rates of development of technologies in this field and the need to modernize already functioning information and technical means. Existing standards and other normative documents can be applied only for real developments, which can not be attributed to the programs developed by students in the learning process, so such documents and standards can not be fully used to assess the level of knowledge of students, because before their application it is necessary to carry out the analysis of the most significant ones and to adapt to the specifics of the learning process. In the process of research, those quantitative characteristics were singled out - metrics that allow to reveal the real level of possession of the student's technologies. Using the obtained quantitative characteristics as an integral system, the teachers have an opportunity to get an objective assessment of the program developed by the student, and such an assessment will fully meet the requirements of a graded rating of students' performance. As a result of the analysis of this area of research, the metrics from the group "Metric characteristics" were singled out and described: the program completion code, the total program execution time, the maximum amount of physical memory used, the maximum number of used memory pages, the maximum amount of virtual memory used, the use of processor time, total processor time, which can be used as a basis for building a software product that performs testing and student programs based on a dynamic approach.
Keywords:
benchmarking system, quality of the program, program evaluation, automation of knowledge testing, dynamic testing of programs, testing system, student programs, program metrics, pedagogical tool, system of program metrics
Automated systems of engineering process administration
Reference:
Lobanov A.A., Mordvinov V.A., Murakov M.V., Raev V.K.
Construction of a model of a multifunctional airborne guidance and landing system for a spacecraft
// Software systems and computational methods.
2018. № 2.
P. 36-50.
DOI: 10.7256/2454-0714.2018.2.26217 URL: https://en.nbpublish.com/library_read_article.php?id=26217
Abstract:
The basic requirements for the on-board complex of the spacecraft for purposes of guidance and landing on small bodies of the solar system are formulated in the work. The main tasks of the landing and landing vehicles are braking and approaching the surface of the celestial body, landing, working on its surface, possibly taking off from the surface to deliver the returned vehicle to the ground. Providing high requirements to the accuracy and reliability of the on-board guidance and landing system, an actual solution is proposed. Using the traditional approach to the modeling of processes and systems, a functional model of the onboard guidance and landing system in IDEF0 notation was created. In the process of creating a functional model, the main processes performed by the complex during descent from orbit and landing are described. As a result of the work, a description of the procedures performed by the multifunctional on-board guidance and landing system of the spacecraft has been obtained. An applied functional model of the "to-be" level was constructed, based on the use of an integrated approach. The proposed integrated approach is focused on the sharing of data from all on-board devices, both basic and backup information. This approach allows to increase the accuracy and reliability of the landing procedure.
Keywords:
landing a spacecraft, guidance of the spacecraft, navigation of the spacecraft, integrated approach, visual guidance, Onboard multifunctional environment, functional model, optical direction finder, optical processing, small bodies
Knowledge Base, Intelligent Systems, Expert Systems, Decision Support Systems
Reference:
Tikhanychev O.V.
Agile technologies in software development of decision support systems
// Software systems and computational methods.
2018. № 2.
P. 51-59.
DOI: 10.7256/2454-0714.2018.2.23743 URL: https://en.nbpublish.com/library_read_article.php?id=23743
Abstract:
The subject of the study is the process of developing software for automated control systems. Object of research - methodologies for organizing software development. Automation of management is a universally recognized promising direction of increasing the efficiency of the application of complex technical systems. First of all, automation, organized by the principle of decision support systems. The basis of the effectiveness of any automated system is its software. First of all, this applies to application software. The development of such programs entails certain difficulties, primarily organizational ones. Generalized analysis has shown that in the world practice there is a rather wide range of methods for organizing the development of programs. These methods can be divided into two large groups with respect to the algorithms used for "hard" and "flexible" ones. Each of the approaches is effective for certain conditions of work. The article analyzes the factors influencing the effectiveness of applying a particular methodology, synthesizes suggestions on the appropriateness of using different methodologies in different conditions of the development process. The analysis showed that for the development of automated decision support systems, the use of "flexible" approaches is most effective. In the article features of Scrum technology are considered, as a typical implementation of "flexible" methodologies. Conclusions about the expediency of its application in the development of application software for automated decision support systems are formulated
Keywords:
development process organization, DMSS, software development technologies, software, automated systems, decision support, control automation, flexible technologies, Agile technology, Scrum development method
Mathematical models and computer simulation experiment
Reference:
Galochkin V.I.
Search for the paths of the minimum total length in the graph
// Software systems and computational methods.
2018. № 2.
P. 60-66.
DOI: 10.7256/2454-0714.2018.2.25124 URL: https://en.nbpublish.com/library_read_article.php?id=25124
Abstract:
Author considers the problem of finding non-intersecting paths of the minimal total length from a given initial vertex to all other vertices on a weighted oriented graph k for non-negative arcs. The author shows that one can not use the "greedy" approach, that is, find the best way, remove the vertices of this path from the graph along with the incident arcs and repeat the search. The problem reduces to finding the shortest paths on an implicit graph of n ^ k vertices with some additional constraints, where n is the number of vertices of the original graph. The sparseness of the implicit graph allows us to use rational data structures, reducing the complexity of the path finder algorithm. The author executed the software implementation of the described algorithm. In the testing process, complete graphs were generated with the values of the arc weights at which the paths of the minimum total length consisted of a large number of arcs. For practical purposes and for computational possibilities, small values of k are of interest. In this case, it is correct to consider the value of k as a constant, and the complexity of the algorithm is estimated by the value O (n ^ (k + 1) log n). The necessary memory costs are O (n ^ k). The running time of the program on various tests does not contradict the obtained estimates of the complexity of the algorithm.
Keywords:
Dijkstra's algorithm, Shortest path, Length of a path, Sparse graph, Implicit graph, Weighted graph, Directed graph, Graph, Yen's algorithm, Complexity of algorithms
Computer graphics, image processing and pattern recognition
Reference:
Korotin A.S., Popov E.V.
Processing of digital terrain models for improving the reliability of the analysis of water basin morphometry
// Software systems and computational methods.
2018. № 2.
P. 67-83.
DOI: 10.7256/2454-0714.2018.2.26383 URL: https://en.nbpublish.com/library_read_article.php?id=26383
Abstract:
The object of the study are open digital terrain models located on the Internet. The subject of the study is the procedure for eliminating the errors of digital terrain models aimed at increasing the reliability of calculations of the morphometric characteristics of basins of water bodies. This article is devoted to the improvement of methods for processing and modifying geoinformation features by processing digital high-altitude relief models. The approaches outlined in this paper are aimed at increasing the reliability of calculating the main morphometric characteristics of the relief by eliminating errors in the original data. Usually for morphometric analysis, cartographic works are used, according to which the defined relief forms contain subjective errors. The values of these errors can then affect the results of the analysis, since the quantitative characteristics depend on where and how the boundary of the form passes. Given the presence in the initial open data of a number of high-altitude distortions that indicate their inapplicability to use for qualitative morphometric analysis at the level of private watersheds, the paper considers ways to adjust their geometric characteristics by eliminating the influence of tree vegetation and preserving the relief's relief using the Lagrange coefficients. A comparison of the results of a particular morphometric analysis obtained using corrected relief models with results obtained from other data is given. To increase the reliability and automate the processing of the digital model of the river basin relief, which is a regular network, it is necessary to carry out analysis in private watersheds with an area from 0.6 to 0.8% of the total area of the basin.
Keywords:
geoinformation system, normalized difference vegetation index, forest vegetation, digital elevation model, Lagrange interpolation polynomial, normal Gaussian distribution, geometric modeling, remote sensing data, morphometric analysis, open source
Software for innovative information technologies
Reference:
Guzii A.G., Kukushkin Y.A., Lushkin A.M.
Computer technology of pilot functional reliability prognostic evaluation
// Software systems and computational methods.
2018. № 2.
P. 84-93.
DOI: 10.7256/2454-0714.2018.2.22425 URL: https://en.nbpublish.com/library_read_article.php?id=22425
Abstract:
The subject of research is mathematical software prognostic evaluation of functional reliability of the pilot. The object of research is the functional reliability of the professional activities of the pilot. The authors consider in detail such aspects of the topic as automated assessment of the risk of an aviation event due to the release of flight parameters for operational limitations, understanding by the risk assessment the probabilistic measure of the occurrence of an aviation event of a fixed degree of severity due to exceeding operational limitations of the aircraft, in flight such an event (depending on the severity effects) is classified as an aviation event, subject to the investigation. The research methodology is based on the system approach and unites methods of probability theory, mathematical statistics, aviation cybernetics, psychophysiology of flight work. The main result of the study is a software-implemented technology for predicting the functional reliability of the pilot, implemented, allowing to implement an individual a priori risk assessment of an aviation event (incident) for a group of causative factors "crew" in the most critical stages of flight (takeoff and landing) Accumulated statistics of aviation events caused by the release of flight parameters for operational limitations, which is important To ensure proactive management of safety levels in the airline. The novelty of the research is that the technology of predictive estimation of the functional reliability of the pilot is developed on the basis of the concept of acceptable risk of an accident.
Keywords:
aviation risk management, flight safety, aeronautical cybernetics, pilot condition monitoring, pilot reliability monitoring, pilot reliability prediction, reliability of the pilot, predictive assessments, psychophysiology of flight work, probabilistic modeling