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

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3
Publication date:
16 September 2019
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Articles of journal № 3 at 2018 year.

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Public date | Title | Authors

11. A mathematical model approach for evaluation of oil recovery changes caused by wettability during in-situ combustion [№3 за 2018 год]
Authors: I.V. Afanaskin , A.V. Korolev, V.A. Yudin
Visitors: 1034
The paper considers a problem arising in simulation of EOR thermal methods that is wettability changes influenced by formation heating. EOR thermal methods may make a formation temperature rise up to 100–500 ºС above the initial value. Wettability may change in time and space as a result of such artificial temperature distribution. Thus, the fluid flow in formation and the result of applying EOR thermal methods may change dramatically. Investigation of wettability temperature changes requires complicated experiments that take into account temperature changes of a big number of physical processes effecting wettability. Before conducting such experiments, it is mandatory to estimate the importance of such factor in forecasting EOR thermal methods result using computer simulation. The article took into account wettability temperature changes by implementing temperature dependence of critical points on phase relative permeability curves, both for oil and water. The authors consider the problem of multi-phase multi-component non-isothermal filtration through with chemical reactions that took into account a temperature dependence of relative phase permeabilities. They proposed an original finite-difference scheme that is implicit on pressure and explicit on temperature and concentrations. The calculations showed that if wettability changes due to temperature profile variability in formation space and time are neglected, considerable errors may occur in estimates of cumulative production and time of oxygen breakthrough in predicting in-situ combustion results by computer simulation. These errors may be as much as 20 % in cumulative production and 10 % in breakthrough time. To take into account this effect, it is necessary to study the changes in wettability (and relative permeability) experimentally with increasing formation temperature.

12. Development of the spontaneous structuring algorithm of natural complex digital images [№3 за 2018 год]
Authors: E.Ya. Ostrovsky, S.V. Rumyantsev, V.A. Fadeev
Visitors: 966
The paper considers the way of improving the algorithm of spontaneous formation of a consistent structure on digital matrix objects with observation data of parameters (magnetic, gravimetric, radioactive etc.) of the natural complex under investigation. In the section “A Spontaneous Structuring Concept: Chaos Self-Organization in Stable Homogeneities – Structure Parts” the authors state the problem. They consider a spontaneous structuring technique that is alternative to traditional technologies and reveals stable properties (signs), creates a unique (only possible) consistent structure. In the section “The Algorithm of Spontaneous Formation of a Unique Highly Informative Structure” the authors consider the algorithm as a sequence of key stages that form the basis of the technique of the spontaneous formation of a consistent structure. The section “Experience in Applying Spontaneous Structuring Technique” gives brief overview of technology application. In section “Human Factor or the Role of an Expert in Using the Technology” the authors emphasize the role of a man as an expert when using the spontaneous formation technology of a consistent structure. The conclusion contains possible applications of the technology. Thus, technology development (conception, algorithm and software) for consistent structure formation in the form of a set of the non-crossing stable multidimensional homogeneities (contiguity associations) that represents regions of adequate extrapolation (forecasting) of objects in them.

13. 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: 1035
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.

14. The approaches to identification of network flows and organization of traffic routes in a virtual data center based on a neural network [№3 за 2018 год]
Authors: Bolodurina I.P., D.I. Parfenov
Visitors: 1467
Every year traffic in data transmission networks grows. Currently, their basis is Big Data traffic. The purpose of this study is to develop new methods for routing traffic in superimposed networks of virtual data centers. The effective construction of routes in modern computer networks that process Big Data flows is one of the most important indicators of the operation of data centers. In order to solve this problem, the authors developed an ensemble of models describing the approach to constructing adaptive routes in superimposed networks of a virtual data center. The novelty of the proposed solution is to develop a hybrid approach that allows (based on methods of data mining) managing routing in a virtual data center network, taking into account data on the status of network nodes, superimposed communication channels and QoS requirements imposed by traffic flows. The proposed route identification model allows solving such problems as determining the order of using chains of superimposed communication channels in a virtual data center network and establishing rules for providing quality of service for mission-critical traffic. A software-algorithmic solution is implemented based on the built models. It is a module for a controller of a software-configurable network. The algorithm described in the paper allows obtaining sets of quasi-optimal and optimal routing rules in polynomial time. The effectiveness of the proposed solution is proved by experimental research using a real network infrastructure of a virtual data center. Comparison of the results of an experimental study carried out using known routing algorithms showed a reduction in response time in the network, as well as a reduction in the load on network nodes processing traffic.

15. 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: 1184
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.

16. Improving the accuracy calculation of time delay automatic control [№3 за 2018 год]
Authors: V.D. Than, Yu.N. Dementev, V.I. Goncharov
Visitors: 750
The article considers accuracy problems of synthesis automatic control systems (ACS) with time delay. The questions cover the traditional approach based on approximation of a delay element transfer function by a rational fractional expression, as well as the original way that allows keeping an accurate description of the delay element when solving the problems of ACS regulator synthesis. The authors choose the last option, which is based on using a special case of the Laplace transform that provides a transition to the description of dynamical systems in the form of image functions with a real variable. This numerical method makes it possible to obtain discrete models of dynamic systems, combining the advantages of numerical methods and digital computing tools. Based on a numerical method the authors consider three topical problems of synthesis and research of the indicated class systems. The first one is related to a delay element approximation. The paper gives a comparative analysis of the approaches based on segments of the Taylor series, Padé fractions and the numerical method. The advantages of the latter are: higher accuracy and, most importantly, it is possible to redistribute the approximation error in the region of small/large values of time. Within the framework of the second problem the paper shows the possibility of forming and solving the synthesis equation for an automatic control system without approximation of a delay element ensuring the achievement of the potentially possible synthesis accuracy. The third problem reveals the possibilities of the numerical method in estimating the accuracy of automatic control system synthesis and the comparison of several options. The authors propose a variant of estimation that does not require the approximation of the delay element. A result is graphically illustrated and proved by numbers of examples.

17. IACPaaS cloud platform for the development of intelligent service shells: current state and future evolution [№3 за 2018 год]
Authors: Gribova V.V., A.S. Kleschev, F.M. Moskalenko, V.A. Timchenko, Fedorischev L.A., E.A. Shalfeeva
Visitors: 1325
The paper describes the main features and functional capabilities of the IACPaaS cloud platform. It provides three models of cloud service delivery: PaaS, SaaS and DaaS. The platform is intended for development of specialized (i.e., oriented to specific domains and/or classes of solved problems) intelligent service shells, as well as for development of applied intelligent services using such shells. Intelligent service shells are also presented as cloud services of the platform. Development (maintenance) of applied services using a shell is reduced to formation (modification) of a knowledge base using the tools provided by this shell and binding it with a problem solver. The problem solver consists of a set of agents that are software components interacting with each other by exchanging messages. Specialized intelligent service shells use a domain-specific conceptual representation, which is defined by the ontology of the domain for which the shell is created, for knowledge representation. The knowledge base formation tool uses such problem-oriented model (language) for knowledge representation to generate user interface oriented on domain experts. As a result, domain experts can form and maintain knowledge bases and databases within a familiar conceptual framework (without cognitive engineers as intermediaries or additional training) and make no mistakes in using the language for knowledge representation. The IACPaaS platform provides a basic (universal) and a several specialized technologies for development of the applied intelligent service shells using tools that support these technologies. In addition, there is a technology of interaction between problem solver agents and external software (not included in the IACPaaS platform). It is based on the standard mechanism of HTTP request processing and the ability to run external software executable files from programs (scripts) located on a web server.

18. Improving logical inference speed of production expert systems using aspect-oriented approach [№3 за 2018 год]
Authors: Goncharov А.А., Semenov N.A.
Visitors: 1126
The reason for active applying of expert systems in various industries is their ability to solve problems of data interpretation, diagnosis, monitoring, design, forecasting, planning and training. Each expert system is based on a knowledge representation model. A production model, semantic networks and frames are the most common models. The production model is the one used most frequently. The paper considers the important shortage of production systems related to low efficiency of the logical inference process compared to other knowledge representation models. The paper describes the proposed method of increasing the efficiency of the logical inference process in production systems based on applying an aspect-oriented approach. The aspect-oriented approach allows identifying intersecting functional elements and providing their consolidation during architecture creation and system implementation. This approach was first introduced in 1997 and it remains popular at the present time. As the example, the article provides a set of production rules of expert system for selecting the requirements for a given level of control according to the requirements of guidance document of undocumented features. In this case, the facts are presented in the form of values of control levels and actions are presented as requirements to the selected level of control. The proposed aspect-oriented approach to organizing production systems provided an opportunity of increasing the speed of logical inference in expert systems. The separation of intersecting facts and actions from the set of production rules into aspects has made it possible to reduce the number of operations when searching for a solution and to eliminate exhaustive search for facts and actions.

19. A neural network method for detecting malicious programs on the Android platform [№3 за 2018 год]
Authors: T.M. Tatarnikova, A.M. Zhuravlev
Visitors: 1194
Continuous growth in the number of malicious programs aimed at the Android operating system makes the problem of their detection very important. The lack of a centralized mechanism for distributing applications and effectiveness of existing solutions exacerbate the problem. The paper demonstrates experimentally the lack of effectiveness of the existing mechanisms for detecting malicious programs in the Android operating system. The need for an automated solution that increases the probability of malicious program detection in the Android operating system including previously unknown modified and obfuscated versions of already known programs determined the purpose of the work. The authors used the methods of neural network classification, static code analysis and analysis of program behavior in a virtual environment. The novelty of the proposed solution is the use of classification features obtained both by static code analysis and by analysis of program behavior on a virtual device. The proposed approach eliminates the shortcomings of existing solutions to the problem under consideration. The ability of the proposed solution to detect malicious programs that were not used in neural network training, as well as obfuscated instances, has been experimentally proven. The practical significance of the proposed solution is its use for building malware detection systems of the Android operating system, which can be applied in the Android application store.

20. 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: 1570
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.

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