Software & Systems

Articles of journal № 1 at 2022 year.

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1. An analysis of the efficiency of the process of servicing the flow of requests for creating IT-services used a simulation model [№1 за 2022 год]
Authors: Abdаlov A.V., Grishakov V.G., Loginov I.V.
Visitors: 2389
The paper discusses the issues of analyzing the effectiveness of the process of servicing the flow of requests for creating IT services using the simulation modeling method. It shows that the well-known sim- ulation tools do not allow full simulation of the application service process in information and communication in-frastructure administration units characterized by the controlled resource flow nature. The study involved the development of software to simulate the process of servicing the flow of requests for creating IT services. Its main difference was the ability to manage the resource source during the process of servic-ing requests and the possibility of simultaneous experiments on the same source data with several service disci-plines. The simulation model was developed in the Microsoft Visual Studio environment and consists of five mac-roblocks: a request generator, a resource generator, a service device, an algorithm block and an experiment block. The algorithm block allows connecting external models in the form of library blocks that implement the request flow processing through a unified interface, including the ability to generate commands to manage the resource source. The experiment block allows performing streaming experiments based on the specified settings and saved experiment files. The main difference of the developed simulation model is the creation of multiple independent request service flows for various algorithms. The possibility of conducting comparative analysis experiments is illustrated by a se-ries of experiments with stationary and non-stationary request flows and stationary, non-stationary and controlled resource flow based on a family of alternative control algorithms. The results of using a simulation model of the process of servicing requests for creating infocommunication services made it possible to evaluate the effectiveness of the developed promising control algorithms within the framework of the study.

2. The method for creating parallel software tools for modeling military complexes [№1 за 2022 год]
Author: Aksenov M.A.
Visitors: 2325
Nowadays modeling systems are actively created and used all over the world including the Armed Forces of the Russian Federation. The basis of these systems are modeling complexes, which are a set of technical and software tools providing calculations and imitation modeling. The analysis of modern software tools for modeling military complexes has shown that the duration of the cal-culations performed during imitation largely influence the efficiency of their application when used directly. Specific technological tools used in the development of parallelization of labor-intensive cyclic sections of modeling complexes allow minimizing the time spent on modeling under conditions of limited terms of using software tools. However, nowadays they are not implemented in the general software architecture of modeling complexes accepted for supply in the Armed Forces of the Russian Federation. The paper considers the issues of choosing parallelization algorithms implemented in parallel software devel-opment tools for multi-core (multiprocessor) shared memory computing systems. The purpose of the paper is to assess the impact of the execution time of parallelized cyclic sections of a target program with multithreaded parallel execution of the program in multi-core (multiprocessor) PCs on the results of combat imitation. The scientific novelty is in the development of a new method for creating parallel software tools for modeling military complexes. The paper provides numeric examples of calculations in the Mathcad. To avoid errors in choosing preferred parallelization algorithms, the entire analysis is based on mathematical statistics elements with the probability of a confidence interval for estimating the cycle execution time by a certain algorithm considering the upper limit of the confidence interval. The author proposes a variant of constructing software tools on the example of introduc-ing technological developments into a software architecture of a modeling complex.

3. Software implementation of the algorithm for finding the optimal temperature condition of the catalytic process [№1 за 2022 год]
Authors: E.V. Antipina , S.A. Mustafina , A.F. Antipin
Visitors: 1332
The paper describes the software for solving problems of optimal control of the catalytic process in an ideal mixing reactor. The general form of the formulated optimal control problem is based on a mathe-matical model of the process in an ideal mixing reactor. The refrigerant temperature is considered a control parameter; its values are limited. In order to solve the problem numerically, the paper presents a step-by-step algorithm based on the evolutionary method of artificial immune systems. The method of artificial immune systems for solving optimal control problems makes it possible to obtain an ap-proximate solution to the problem in a time that is acceptable from a practical point of view. The formulated algorithm is a basis for the developed application for the catalytic reaction of α-methylstyrene dimerization in the presence of the NaHY zeolite catalyst, whose products (linear di-mers) are widely used in industrial production. To calculate the process in an ideal mixing reactor, the program implements a number of numerical methods. The software tool allows the user to customize both the catalytic process parameters and the parameters of the algorithm of the artificial immune system method. The user sets the optimization criterion during the program operation, which makes it possible to use it for various formulations of the tasks of the catalytic process of α-methylstyrene dimerization and to obtain a set of optimal concentrations of substances and optimal temperature conditions that correspond to the specified process indicators. The paper gives a solution to the problem of finding the optimal tem-perature condition for the considered catalytic process, the optimality criterion of which is the achievement of the maximum yield of linear dimers with a minimum yield of cyclic dimers and trimers.

4. An algorithm for ensuring the required level of stability of control of an unmanned aerial vehicle in the conditions of counteraction [№1 за 2022 год]
Author: Belonozhko D.G.
Visitors: 2101
The paper proposes an algorithm for ensuring the required stability level of controlling an unmanned aerial vehicle (UAV) in the conditions of counteraction. It is assumed that the external influence includes both intentional de-structive influences and unintended environmental influences. The sustainable control of UAVs is considered as the ability of the governing bodies to perform their functions in a complex sharply changing environment under conditions of interference, enemy influence (fire, electronic, etc.) and technical failures, keeping the values of all control indicators within the established limits, respectively. The paper considers the means of fire and physical destruction, electronic suppression, as well as means of functional damage by electromagnetic and laser radiation as deliberate destructive environmental influences that threaten to disrupt the stability of UAV control during automatic control. Depending on the probability of defeat-ing a UAV after deliberate destructive influence of the external environment, there are formed zones that charac-terize the influence of influence means on the level of UAV combat capability. The determined acceptable level of stable control probability meets the requirements of a UAV combat-ready state. In order to ensure the required stability level of UAV control, the author used the principle of adaptive control that consists in changing the parameters of the UAV movement to implement the possibility of overflying danger-ous zones. The calculation of the UAV motion control parameters used a mathematical model of the dynamics of the UAV lateral movement. The UAV motion control parameters are formed as a sum of program and corrective control calculated through the required motion parameters of the UAV. The proposed algorithm takes into account the possible intentional destructive impact of the external environ-ment. It can be implemented using microcontrollers of modern UAVs and does not involve making changes to their design. The implementation of the algorithm in UAV automated control systems will effectively solve the tasks of aerial reconnaissance in counteraction conditions to calculate the required motion parameters and to con-trol the UAV corresponding to the current situation.

5. Intelligent analysis and processing large heterogeneous data for parrying threats in complex distributed systems [№1 за 2022 год]
Authors: Brekotkina E.S. , Pavlov A.S. , S.V. Pavlov , O.I. Khristodulo
Visitors: 2454
The paper proposes a method of intelligent analysis and processing of large heterogeneous data for predicting threats in complex distributed systems. The method is based on the results of automatic monitoring of changes in water level in water bodies and air temperature at the measurement point. Such monitoring makes it possible to increase the efficiency of planning and implementing measures to fend off such and similar threats. The method is based on general approaches and mathematical models previously used by the au-thors to develop adaptive algorithms for controlling gas turbine engines. It is particularly relevant in the context of the increasingly widespread introduction of software and hardware systems for monitor-ing the state of complex distributed systems and the exponential growth in the number of data used to support decision-making. The choice of the future value of the water level at the measurement point is based on the results of processing the data accumulated over all previous flood periods on the compliance of the water level and its changes per day with the values of air temperature and its changes over the same day. The ana-lyzed data are the values of air temperature and water level measured at equidistant points in time, computational values of changes in the water level and air temperature, as well as forecast values (ac-cording to the official data of the hydrometeorological service) of changes in air temperature. Based on the calculation of the retrospective frequency of changes in this temperature and the water level at the corresponding point, it is proposed to choose as the predicted the value that corresponds to the maxi-mum frequency of occurrence of such a combination of measured parameters. The paper presents the results of an experimental assessment of the accuracy of forecasting the wa-ter level in the water bodies of the Republic of Bashkortostan in the flood period of 2021 are. They confirm the applicability of the proposed forecasting method to support decision making to fend off threats in complex distributed systems from a sharp rise in water, even with the current insufficiently automated observation system. With a wider change in highly automated software and hardware com-plexes for monitoring the flood situation, the amount of data analyzed and processed by software sig-nificantly increases, which will complicate the application of traditional methods of data use, and, on the other hand, will increase the efficiency and relevance of the method proposed in this paper.

6. Systems and approaches for processing information represented by large dynamic graphs [№1 за 2022 год]
Author: Gulyaevsky S.E.
Visitors: 2469
The paper performes an overview of the key features and advantages for the main existing approaches and systems for processing large graphs on a personal computer. The analysis involves single PC graph processing systems such as GraphChi, TurboGraph, GraphChi-DB and distributed systems like Apache GraphX. Special attention is paid to the problems that require significant changes in the graph structure during the commutation process and the details of implementing such algorithms in graph processing systems. The conducted experiments used a well-known algorithm for network inference based on the ob-served spread of infections among the population, or the spread of news and memes in social networks. The algorithm relies on a stochastic gradient to obtain estimates of the time-varying structure and tem-poral dynamics of the proposed network. The algorithm was implemented for GraphChi and Apache Spark computations models. The authors measured the performance for various real and synthetic da-tasets, described several limitations for these computation models discovered during experiments. Computations were performed on a single computer for GraphChi, and on a cluster of various sizes for the Apache Spark based implementation. According to the results of the review and the conducted experiments, the existing systems are di-vided into three classes: fast systems with static graph partition and expensive repartition with signifi-cant structure changes; on average, slower systems that are able to handle large amounts of changes ef-ficiently; even more slower but highly scalable systems that compensate low single node performance with the ability to scale computation to a large number of nodes. The conclusion drawn from the con-ducted review and experiments shows that the problem of dynamic graphs efficient storage and pro-cessing is still not solved and requires additional research.

7. The adaptive image classification method using reinforcement learning [№1 за 2022 год]
Author: Elizarov A.A.
Visitors: 3234
The paper proposes a method for image classification that uses in addition to a basic neural network for image classification an additional neural network able to adaptively concentrate on the classified im-age object. The task of the additional network is the contextual multi-armed bandit problem, which re-duces to predicting such area on the original image, which is, when cut out of the classification process, will increase the confidence of the basic neural network that the object on the image belongs to the cor-rect class. The additional network is trained using reinforcement learning techniques and strategies for compromising between exploration and research when choosing actions to solve the contextual multi-armed bandit problem. Various experiments were carried out on a subset of the ImageNet-1K dataset to choose a neural network architecture, a reinforcement learning algorithm and a learning exploration strategy. We con-sidered reinforcement learning algorithms such as DQN, REINFORCE and A2C and learning explora-tion strategies such as -greedy, -softmax, -decay-softmax and UCB1 method. Much attention was paid to the description of the experiments performed and the substantiation of the results obtained. The paper proposes application variants of the developed method, which demonstrate an increase in the accuracy of image classification in comparison with the basic ResNet model. It additionally consid-ers the issue of the computational complexity of the developed method.

8. Modeling an air route network structure with prefractal graphs [№1 за 2022 год]
Author: R.A. Kochkarov
Visitors: 1340
The paper highlights the main research areas: designing a network with given numerical characteristics, calculating the stability of a given network and a solution, solving optimization multicriteria problems with many parameters, and modeling dynamic networks. The structure of networks is hierarchical, with high clustering parameters; it has the properties of self-similarity at the global air transportation level. Air traffic networks are referred as scaleless net-works or “small world” type. Their analysis involves using the theory of complex networks. The au-thors propose the apparatus of prefractal graphs as a tool for solving optimization problems. They also give basic definitions and notations, consider dynamic rules for generating graphs. In order to solve NP-complete problems in transport and logistics systems, it is proposed to use a method that reduces the complexity for a number of subtasks. The paper considers a model for covering an air route network with a prefractal graph, proposes to state a multicriteria problem of locating a multiple center with many weights, and gives a radial metric estimate. There is a proposed algorithm for placing a prefractal graph multiple center while maintaining the adjacency of old edges. Therefore, the authors generate a graph and select the multiple center verti-ces. The rules for generating a prefractal graph make it possible to generate networks with predeter-mined characteristics, such as vertex centrality, diameter, etc., including those for building air routes, locating airports and transfer hubs. The promising directions of further research are the recognition of real aircraft networks in the form of dynamic graphs, weighing by many weights and formulation of optimization multicriterial tasks, analyzing network structural characteristics, a statistical analysis based on small network structural el-ements, generating networks with specified properties and comparing them with real networks, analyz-ing structural stability of networks, etc.

9. A software package prototype for analyzing user accounts in social networks: Django web framework [№1 за 2022 год]
Authors: Oliseenko V.D., Abramov, M.V. , Tulupyev A.L. , Ivanov K.A.
Visitors: 2915
The paper considers the issues implementing a prototype of a research and practical complex to auto-mate the analysis of user accounts in social networks. Such prototype is used as a tool to indirectly as-sess users’ psychological features manifestation, their vulnerabilities to social engineering attacks as well as to develop recommendations for protection against these attacks. The prototype is developed in the Python 3.8 programming language using the Django 3.1 web framework and PostgreSQL 13.2, Boot-strap 4.6. This paper aims to increase the efficiency of extracting information from data posted by users in social networks, which allows indirect assessment of psychological, behavioral and other characteris-tics of users. The goal is achieved by automating data extraction and developing tools for their analy-sis. The subject of the study is the methods of automated extraction, pre-processing, unification, and presentation of data from users' accounts in social networks to protect them against social engineering attacks. A prototype application based on the Django web framework solves the problem of automated ex-traction, preprocessing, unification, and presentation of data from user accounts in social networks. The solution of this problem is one of the essential steps to build a system for analyzing the security of users from social engineering attacks. The theoretical significance of the work is in the combination and validation through the automation of previously developed methods and approaches to recover missing values of the attributes of the account, the comparison of online social networks users' ac-counts for their belonging to the same user. The practical significance comes from the development of an application tool located on the sub-domain sea.dscs.pro, which allows performing primary analysis of users' accounts in social networks.

10. An algorithm of idiom search in program source codes using subtree counting [№1 за 2022 год]
Author: Orlov D.A.
Visitors: 2669
The paper is dedicated to programming idiom extraction algorithm design. Programming idiom is the fragment of source code which often occurs in different programs and used for solving one typical pro-gramming task. In this research the programming idiom is a source code fragment that often occurs in different programs and used for solving one typical programming task. In this research, the program-ming idiom is considered as the part of a program abstract syntax tree (AST), which provides maximum reduce of information quantity in a source code, when all of programming idiom occurrences are re-placed with certain syntax construction (e.g., function call). The developed subtree value metric estimates information amount reduce after such replace. There-fore, the idiom extraction is reduced to search of subtree value function maximum on AST subtree set. To reduce a number of subtrees inspected, the authors use steepest descent method for subtree value function maximum search. At each step subtree is extended with one node, which provides maximum increase of a subtree value metric. Subtrees are stored in a data structure that is a generalization of a trie data structure. The paper proposes an accelerated algorithm of idiom extraction. Programming idiom extraction speedup is achieved through reusing results of idiom efficiency maximum search. The paper also de-scribes the implementation of the developed algorithms. The algorithms are implemented in Python programming language. The implementation extracts programming idioms from source code written in Python. This programming language is chosen due to a large corpus of texts written in such language; it also includes convenient tools for building AST. The authors carried out an idiom extraction experiment using the developed implementation. The idioms were extracted from corpora of an open-source program source code. The extracted program-ming idioms are source code fragments with own meaning. It is also shown that applying developed al-gorithms to a source code of a single software project can reveal possibilities of investigated program refactoring.

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