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№2
Publication date:
16 June 2019
Articles of journal № 3 at 2018 year.
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1. F-Ranking: a computer system for ranking fuzzy numbers [№3 за 2018 год]
Authors: A.V. Radaev, A.V. Korobov, Yatsalo B.I.
Visitors: 987
In many areas of human activities, people face uncertainties. One of the ways of handling and analyzing uncertainties is using fuzzy sets including fuzzy logic and fuzzy numbers. The use of fuzzy numbers within decision analysis inevitably leads to the problems of their comparison and ranking. Despite the variety of ranking methods, the majority of the existing systems with fuzzy numbers use only defuzzification methods. However, the replacement of a fuzzy number by one real number (like the replacement of the probability distribution density by the corresponding mathematical expectation) inevitably leads to narrowing and loss of information in the original fuzzy number. The paper presents an original computer system F-Ranking for ranking different fuzzy numbers. The system allows using fuzzy numbers with singletons, triangular, trapezoidal and piecewise (including sectionally continuous from above) fuzzy numbers as input data. F-Ranking system includes six methods for ranking fuzzy numbers based on defuzzification: three defuzzification based ranking methods (a centroid index, median, and an integral of alpha-cut mean values) along with two ranking methods based on pairwise comparison (Fuzzy Rank Acceptability Analysis) using Integral and Yuan’s fuzzy preference relations. For the last two methods, a preference fuzzy measure of one fuzzy number over another as well as Fuzzy Rank Acceptability Indexes are available. The paper briefly describes the algorithms of the mentioned methods. The authors make a review of existing systems, which can be used for ranking fuzzy numbers. There is the structure of F-Ranking system with input/output forms and examples of ranking fuzzy numbers using different methods. These examples show the features of the ranking methods under consideration as well as the possibilities of F-Ranking system in general.
2. An automated system of information accessibility protecting from attacks by unauthorized traffic in UNIX-like systems [№3 за 2018 год]
Authors: E.V. Palchevsky, A.R. Khalikov
Visitors: 1160
The paper is devoted to the development of a software module for protecting information accessibility during massive DoS and DDoS attacks. The developed system allows automatically determining a type and form of attacks by unau-thorized traffic, and also filtering network packets by a specified limit (from 10 thousand to 7 million per second), with subsequent load distribution by physical and logical cluster cores. At the first stage of development, DoS and DDoS attacks were analyzed, and similar solutions for a DDoS protection system were examined. The second stage is technical development of the automated system for protecting information accessibility AntiDDoS. The authors show basic functionality and the operation scheme of the DDoS attack protection system. The basic functionality is represented by the following technical data: the name of the function, the execution goal, the operating condition and the result of execution. The third stage is approbation of the implemented system within ten days. The results are presented in a table with an average daily load on computer resources. The created information accessibility protection system allows effectively filtering network packets in an automated mode, as well as sending all data to the MySQL database, and then outputting information to the web interface. The web part is one of the control parts of the developed system. It implements the ability to manage the system from personal computers/servers and mobile devices. The developed information accessibility protection system from AntiDDoS unauthorized traffic attacks has shown high stability and reliability when filtering network packets in large and small volumes. The average CPU load during DDoS attacks is 6.64 %. Whereas without using this system, the load during DDoS attack can increase to 100 %. Reduced load is acceptable and allows simultaneous running complex computational operations without disrupting the system.
3. Adequate interdisciplinary models in forecasting time series of statistical data [№3 за 2018 год]
Author: B.M. Pranov
Visitors: 1192
Statistical studies commonly use multivariate linear models to model and predict time series. Their application area is quite extensive. They are quite effective in a situation when a set of points depicting the objects under investigation in a multidimensional parameter space is located near a certain linear subspace (or its shift relative to the origin). Factor analysis easily reveals this effect. If there is no such subspace (linear set), nonlinear dependencies are used to construct more accurate models. In the economy, the Cobb-Douglas function is used to describe the dependence of enterprise profits on the number of employees and the value of fixed assets. It turns out that if we consider fires and other phenomena of society as a kind of its “production”, then the Cobb-Douglas function allows approximating a corresponding time series with a high degree of accuracy. As a result, we get a number of interesting models in the new subject areas. The results of calculations showed that the Cobb-Douglas function is good at approximating the time series of the total number of fires in the territory of the Russian Federation. The prognostic values calculated by such models are very close to the real ones. A significant number of European countries, as well as the United States use a similarly adequate approximation of the time series of the total number of fires. Such modeling is also appropriate for a tourism industry. The paper considers the models of total hotel income depending on the number of employees and the size of fixed assets.
4. An algorithm of information security residual risk assessment taking into account a protection mechanisms separation by types [№3 за 2018 год]
Authors: D.A. Derendyaev, Yu.A. Gatchin, V.А. Bezrukov
Visitors: 973
Analyzing modern approaches to assessing the risk of information security threats, the authors conclude that most of these approaches do not consider protection mechanisms separation by types, which would allow a better analysis of the existing protection system in an enterprise. The presented algorithm takes into account such separation and considers each type with an emphasis on its features. Due to the absence of clear separation of protection mechanisms, it is proposed to divide them into two groups: technical and organizational. To calculate residual risk, the authors taken into account additional variables, such as a possibility of the correct operation of the protection mechanism and the possibility of overcoming the mechanism in threat materializing. Technical protection mechanisms reqiire taking into account the probability of transition to an inoperative state over time. Considering organizational measures, it is worth considering an expiration of its validity or its changing due to changing conditions. Such processes have random nature, therefore the mathematical apparatuses of the hidden Markov model and random Markov processes are used to determine their probabilities. The final indicator of residual risk is determined using an alternative mathematical model obtained after a full factorial experiment. This model allows obtaining more correct values as it considers input parameters at upper and lower levels. As a result of the algorithm implementation, the values of residual risks are determined taking into account counteraction to the threat of each type of protective measures, which allows identifying the disadvantages of the protection system more precisely.
5. Algorithmic undecidability of the problem of first-order correspondence of computational tree logic formulas [№3 за 2018 год]
Authors: M.N. Rybakov, L.A. Chagrova
Visitors: 679
It is common to use the first-order language as a formal tool for describing properties of various (computational) structures. On the one hand, this language is well understood and easy to use; on the other, many questions that are im-portant from the applications point of view related to this language are algorithmically undecidable, i.e., cannot be answered using a computer program. These days, there exist various alternative languages that can be used for describing computational processes and their properties, for which the corresponding questions are, in contrast to the first-order language, algorithmically decidable. In this paper, we consider one of such languages, – the language of the Computational Tree Logic (CTL). It is commonly used for program verification as it is capable of describing properties of computational processes, – in particular, properties of the binary relation used in the Kripke semantics. The authors investigate the possibility of finding algorithmically first-order formulas defining the same classes of Kripke frames as the formulas of the language of CTL. It is well known the problem of finding first-order correspondents of propositional intuitionistic formulas is algorithmically undecidable. The authors reduce – using the Gödel translation of intuitionistic formulas into modal ones, and subsequently a translation of resultant modal formulas into CTL-formulas – the first-order correspondence problem for propositional intuitionistic formulas to the first-order correspondence problem for CTL-formulas on Kripke frames. As a result of this reduction, they prove that the first-order correspondence problem for CTL-formulas is algorithmically undecidable. In the conclusion, the authors discuss some possible modifications of their construction for fragments of the language of CTL as well as algorithmic decidability of the CTL correspondence problem for first-order formulas.
6. Algorithmic ware of data processing for elastomer composite structuring to solve a control problem [№3 за 2018 год]
Authors: A.S. Kuznetsov, Kornyushko V.F.
Visitors: 864
Structuring is the most important stage of processing multicomponent elastomeric material into a finished product that is a product with a set of operational properties specified at the stage of recipe building. It is a combination of two processes: chemical interaction of various components in its composition, and the technological process of fixing the re-quired properties and functions of the future product. Successful implementation of this final technological procedure requires strict control over compliance with a given sequence of all technological stages and preparatory operations that leads to production a semi-finished intermediate product. Improving the quality of the finished product is greatly facilitated by applying express-control methods based on vibroreometry to assess the characteristics of raw materials, as well as the parameters of the semi-finished and finished products. The paper considers chemical-technological processes of mixing and structuring multicomponent elastomeric composites as components of a chemical-technological system. The authors propose algorithmic support of vibrereometry data processing to improve management efficiency of complex chemical-technological processes of mixing and structuring multicomponent elastomeric composites. The paper describes the constructed process model for controlling the structuring of elastomeric composite systems. There are 4 groups of processes responsible for quality indicators of structuring. There are also block diagrams of control algorithms for complex chemical-technological processes of mixing and structuring of elastomeric systems. The authors show the methods of processing the main rheometric information using modern software products, as well as the techniques for visualizing rheometric data in Table curve 2d and Table curve 3d. Spatial images are constructed in the form of response surfaces for main recipe-technological factors and process quality indicators. There is also an algorithm for calculating coefficients of mathematical models. A set of composition-property diagrams visually characterizes the effect of changing levels of prescription and technological factors on the kinetics of the structuring process. It is shown that visualization of rheometric data using modern software products provides opportunities for more flexible and adaptive control of the process of structuring multicomponent elastomeric composites.
7. Input language of a computer-aided system for shaft forging [№3 за 2018 год]
Authors: Kanyukov S.I., Konovalov A.V., Muizemnek O.Yu.
Visitors: 976
A computer-aided system for shaft press forging design has been created at the Institute of Engineering Science, Ural Branch of the Russian Academy of Sciences. The linguistic support of this system includes a specialized input language for input of initial information and operational adjustments of intermediate and finished results of forging design by users. The input of initial information can be done by two ways: inputting information of a new forged part or reading and adjusting (if necessary) information of a forged part (or a forging), which is already available in a database. The input language part responsible for inputting information of a new forged part provides filling three zones of a corresponding menu. These zones contain general information on the forged part, on the forged part geometry and a design plan. The latter includes a list of tasks to be done in the computer-aided design of forging. Computer-aided design of forging includes the assignment of machining and heat-treatment allowances, addition of various specimens for mechanical testing and macro-control, assignment of forging overlaps, a definition of technical requirements and a simulation of a workpiece working drawing, which consists of seven graphic zones. The input language part responsible for adjusting the workpiece working drawing allows selecting a drawing format (A3 or A4), changing the size of graphic areas with scaling geometric objects and moving them within the drawing field, adjusting numerical and text values of forging parameters inside zones by drop-down menus, controlling the visibility of zones. The described input language of the computer-aided technological design system provides convenient input of initial information about forged parts, ensures obtaining workpiece working drawings suitable for production processes, and greatly facilitates system adaptation to different enterprise conditions.
8. A package manager for multiversion applications [№3 за 2018 год]
Authors: Galatenko V.A., M.D. Dzabraev, Kostyukhin K.A.
Visitors: 730
All software developers eventually face the problem of creating and distributing their software products. At the same time, it is necessary to take into account possibilities of supporting existing products, i.e. replacing old distributions with new ones. When using a quality distribution tool, developers are able to distribute their products to a wider range of platforms, as well as provide the necessary and timely support for these products. The authors of the article consider only UNIX-like systems, most of which include package managers as dpkg, yum. These package managers operate according to a standard concept of software installation in UNIX. The standard concept implies that programs are installed in standard directories such as /usr/bin, /usr/local/bin, and so on. When updating a program (package), it is common practice to replace old files with new ones. Such substitution strategy can be destructive. This means that after software update, some programs or libraries stop working. It is possible, for example, that a package manager itself may stop working after updating. A user is often in a situation when old versions of software are required to support compatibility. In this case, it is necessary to use the practice of building programs and libraries from source code and manual installation, such as “make install”. This kind of installation is irreversible and very dangerous, since in this case the files under control of a package manager may be deleted or replaced. The authors propose a package manager NIX [1] as a solution for the described problems. The most important advantage of this manager is that it completely excludes destructive impact on its part. This is achieved by installing each package in an isolated location controlled by a package manager.
9. High-level architecture of training simulation systems of complex technical systems [№3 за 2018 год]
Authors: A.V. Roditelev , Giatsintov A.M.
Visitors: 1340
The paper provides a detailed description of the training simulation system (TSS) architecture using the example of an air simulator prototype. A TSS visualization subsystem provides visualization of external environment and a control object using display devices. It should provide reproduction of the created virtual scene with a sufficiently detailed content that allows TSS operators to perform the assigned tasks successfully. The authors give the requirements for TSS subsystems, including those for the TSS visualization subsystem. The developed architecture avoids high coupling of components and provides a unified approach to managing hardware, such as various input devices. Usually, a device has some peculiar properties: specific control software, closed information exchange protocols, different connector types. The developed plugin management systems allows taking into account various hardware features without modifying the main module and other subsystems. The created control interface works with pluggable modules. Plugins are self-sufficient and can be added or removed without violating the integrity of the system. Depending on the workload, data processing can be organized on one machine or each subsystem can operate on a separate machine. Each subsystem is a standalone software complex that may be developed by a third-party developer. The main module and its subsystems can operate on hardware complexes with different processor architectures, endianness (little or big) and operating systems. The paper also describes an algorithm that transforms geographic coordinates received from the modeling subsystem to the coordinate system used by the visualization subsystem.
10. Carbonate reservoirs crosswell survey interpretation by a two-rate test using numerical models [№3 за 2018 год]
Authors: I.V. Afanaskin , S.G. Volpin, O.V. Lomakina, Yu.M. Shteynberg
Visitors: 863
The paper describes a two-rate well test method that is applied at transient flow. Due to recent development this method allows defining a set of parameters that is the as wide-spread pressure build up test. It is established that the method investigates few dozen meters area, rarely hundreds. The two-rate method doesn’t require well shut-in, so oil output loss reduce during the research. A disadvantage of the method is that parameter calculation is not so precise. The paper shows that at significant rate difference between two modes and sufficient second-rate longevity the two-rate method is a reasonable alternative to interference test. In this case, test area between wells increases to a hundreds of meters. The paper describes a dual-porosity mathematic model for crosswell carbonate fractured reservoir well test interpretation. This model is applicable for crosswell reservoir two-rate test data interpretation. There is a “classic” original finite-difference calculation scheme for this model. The authors describe a reverse-problem subsurface hydrodynamic solution by Newton method. The method has been applied to synthetic downhole pressure curve with corresponding recommendations. Few interpretation variants presented for different reservoir parameters refinement. A relative fractured volume and matrix-fractures diffusivity coefficient have low influence on a tested well at late time pressure value. It is recommended to include fractures permeability, matrix porosity and area fractures anisotropy as defined parameters.
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