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In this paper, the author uses the software package ScicosLab to conduct experimental modeling
of common secure communication systems and their experimental analysis using known methods of
nonlinear dynamics (time and spectral diagrams, phase portraits, Hurst exponent, maximal Lyapunov
exponent, BDS-statistics). As a common secure communication systems was chosen as the communication
system based on direct spread spectrum communications, system on the basis of the noise signals,
the proposed Shagarova A. A., communication system based on chaotic masking and communication
system based on chaotic modulation, represented by apparatus for protection against imitation
of controlled objects with high structural security of carrier signals. As a result of researches it was
established that: BDS-statistics explicitly identifies communication systems on the basis of classical
approaches of formation of noise-like signals and their derivatives; communication systems on the
basis of classical approaches of formation of noise-like signals and their derivatives possess positive
maximal Lyapunov exponent and thus possess chaotic properties; the obtained quantitative values of
BDS-statistics, maximal Lyapunov exponent, the Hurst exponent indicate that communication systems
based on chaotic signals in general are more preferable for secure communication systems than
communication systems based on classical approaches to the formation of noise-like signals and their
derivatives; of the considered communication systems based on chaotic signals, the system based on
chaotic modulation is more preferable for secure communication systems, since it has the highest maximal
Lyapunov exponent, which is an indicator of greater protection against unauthorized access than
the considered analogues, as it is indicated by the obtained values of BDS-statistics.
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The paper presents the results of experimental studies of the effectiveness of the application of distributed
models in comparison with their monolithic analogs. As a basic model, models based on the
mathematical apparatus of Petri nets are used. In particular, special expansion of ordinary, temporary
Petri nets with inhibitory arcs, oriented to modeling of digital devices of automation and computer facilities.
A description of the indicators used to evaluate the effectiveness of monolithic and distributed
models is given. The advantages and disadvantages of these types of models are discussed. The short
description of this model, indexes for assessment of effectiveness and conditions of carrying out an
experiment is given. Analysis of effectiveness of the distributed models allowed to select two feature.
The first is that, in process of increase in their size, the efficiency factor of the distributed models continuously
increases. At the same time, models with the smaller number of hierarchical levels are more
efficient. The second feature is that, in process of further increase in the sizes of the distributed models,
the effectiveness on speed of models with a large number of hierarchical levels becomes not only
equal, but to exceed effectiveness of models with their smaller quantity.
It is shown, that high-speed performance of the distributed models can be two orders more, and time
of their loading is tens times less, than similar indices at monolithic models.
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№ 6(78)
28 december 2018 year
Rubric: Automated control systems Authors: Stepanenko N., Alekseeva T. V., Gubina L. |
Automating a company’s business processes is an important part of optimizing its operations.
The automation process is a project activity based on the principles of achieving the goal, spending
resources and meeting deadlines. The choice of automation method depends on many criteria (preferences,
desires, technical and cost components) that must be considered in the planning of the project.
The method of analyzing hierarchies will make it possible to organize in the best way the decisionmaking
process regarding the choice of an automation method.
The hierarchy analysis method, developed by the American mathematician Thomas Saaty about
30 years ago, is still widely used in practice for making decisions in all subject areas. In matters of choosing
how to automate business processes of a company, this method is the best fit, because It makes it possible
in the best way to take into account in the project all the requirements for the future system, to ensure
the most acceptable functionality, to organize the most effective implementation and further support.
The effectiveness of its use in the selection of automation systems is demonstrated by the example of the
construction company PSK «Dom-skazka» engaged in automatization of business processes. To solve our
problem, six criteria were chosen. As a result of the analysis, a response was received, allowing to decide
on the choice of how to automate the production process. In the article, the authors consider an example
of applying the hierarchy analysis method in solving the problem of choosing an automation method.
The task has been set, alternatives have been chosen, selection criteria have been described, mathematical
calculations have been carried out and the results have been obtained, on the basis of which a reasonable
choice of the best alternative (automation method) has been made for the company in question.
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Today, almost every commercial organization has its own website. And every owner of his
web resource aims to generate income from it. You can increase revenue from your site
as a business tool in various ways. One of such methods is search engine optimization (SEO),
which is a complex website promotion in search engines (SE) by increasing its visibility on specific
search phrases (keywords). The result of this optimization is an increase in traffic to the site.
The article shows what indicators need to be used to assess the quality of SEO-promotion
of online shopping sites.
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The presented article describes a functional approach and methodology to managing the internal
environment of an intelligent building (or «smart building»), which implies the use and transfer between
the peripheral equipment and central engineering and (or) automated systems of unchangeable
states, the absence of side effects and uncertainty in the implementation of control actions and the construction
of a decentralized network of computations and decision making at the edge side based on
the so-called «Internet of things». The mathematical foundations of the organization of a distributed
computing environment for the realization of a functional approach are considered. Brief descriptions
of possible control scenarios in various modes of operation of engineering and automated systems of
intelligent buildings are described. A theoretical basis is provided for recommendations on changing
the paradigm of design and constructing a general centralized automated control system for an intelligent
building from the automation of engineering processes to the intellectualization of management
and the creation of an artificial intelligence system that implements a complete and autonomous cycle
of building management and exploitation. The paper would be of interest for designers, system architects,
software engineers and scientists, who work in the area of implementing of smart solutions on
various levels of automation.
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Testing students is one way to verify their knowledge. Any person, one way or another, meets with
the passage of tests related to his professional activities, training or re-certification. Of course, tests
are a serious psychological strain on the subjects, especially in conditions of limited testing time and
the number of attempts. Therefore, the actual question is: how to properly organize testing to obtain
the maximum positive effect.
For comparison: in order to pass the professional tests Microsoft or Oracle companies to receive
the certificates of experts or professionals in software these companies need to respond to 75% of the
questions correctly. Moreover, the delivery of such tests is carried out in specially equipped, isolated
rooms, in the complete absence of mobile phones, tablets, iPads and other similar means.
Having tried various methods of testing, the author, having considerable professional experience
in the field of programming and creating users’ workplaces, decided to develop a testing system on
his own. Software development for testing was carried out using the RAD programming environment
Embarcadero Delphi, which made it possible to create an interface convenient for the end user.
The main business logic of the testing system was implemented as Microsoft SQL Server stored procedures,
which ensured high performance, system scalability and reliable information protection from
unauthorized access.
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