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 Выпуск 115
- Gezha V., Kozitsin I. Controlling opinions in the scardo-model of opinion dynamics with two-element opinion alphabet and single type of native agents: analytical solution
This paper investigates a control problem whereby a concerned person attempts to change individuals' opinions by using a group of social bots -- stubborn agents that can influence other, native, agents via direct conversations. The control problem is formulated in terms of the mean field approximation for the SCARDO-model, built for the case of a social system with a modular network structure, heterogeneous levels of agent activity and content personalization. We focus on, perhaps, the simplest case of the two-element opinion alphabet, in which there are only two possible opinions (interpretation -- elections in a two-party system) and one type of non-bot agents. We derive a precise analytical solution to the control problem and demonstrate that depending on the model parameters, there can be either one optimal control strategy or infinitely many. At the same time, in the case when there is only one optimal control trajectory, it should be organized as follows: all social bots should broadcast the same opinion, and the switch to a different opinion can occur no more than once, only for some parameter configurations. The theoretical results obtained are complemented by insightful examples with data from the online network VKontakte.
- Postnova O., Tananko I., Rogachko E. An approximation for the response time in fork-join queueing networks
An open fork-join queueing network is considered. An arriving job is
split to be serviced into two tasks. The tasks are serviced independently at multiple service-nodes. Each service-node is a queueing system with one server and infinite capacity queue. Service-nodes form a queueing network with an acyclic topology. Two tasks associated with the job synchronize at a join-node before they leave the network. Approximations for the mean time spent by a task in the join-node and the mean response time in the fork-join queueing network are derived by assuming that jobs arrive according to a Poisson process and task service times have an exponential distribution. The accuracy of these approximations is demonstrated by comparing approximate results to simulation results. These approximations can be applied to the analysis of queueing networks with relatively small steady-state workload. The results can be used for the performance analysis of multiprocessor systems and other modern distributed computing systems.
- Salimzyanov R., Moiseev A., Sushchenko S. Infinite-server queueing network with abandonments
The paper presents a study of a queueing network with an unlimited number of servers in the nodes and service abandonments. Using such a model, a subscriber access network can be described. In the considered network, a connected subscriber can move from one node of the network to another during the service process or leave the network, having completed or not completed its service. It is assumed that such transitions occur independently of the current state of the nodes. The study is carried out using the method of asymptotic analysis under the condition of high input flow intensity. It is found that in the specified asymptotic regime, the joint stationary probability distribution of the number of subscribers in the network nodes converges to a multi-dimensional Gaussian distribution. Explicit expressions for the parameters of this distribution, including the mean vector and the covariance matrix, are obtained. Numerical experiments are performed to evaluate the accuracy of the approximation, and the domain of applicability of the results is established depending on the model parameters. In addition, an example of solving an optimization problem for the studied queueing network is provided, demonstrating the potential practical application of the proposed model and analytical methods for the analysis and management of telecommunication systems.
- Tali D., Finko O. Electronic document model within the industry 4.0 paradigm
The digital transformation of society and production is gradually entering the stage of Industry 4.0, when the servicing infrastructure, including automated information systems of legally significant electronic document management, will be able to independently understand their environment and adapt to the current conditions of the situation. However, the current stage of development of such systems is characterized by the imperfection of the terminology and the identification of the object of influence (electronic document) with its paper prototype, which leads to a limitation of their functionality. Thus, the existing paradigm of perception of an electronic document does not correspond to the promising level of development of automated information systems of legally significant electronic document management within the framework of the concept of Industry 4.0. The purpose of the work: the formation of models of an electronic document and a description of the method of ensuring its integrity, which allows to guarantee the achievement of the required level of security of automated information systems of legally significant electronic document management, functioning in accordance with the provisions of the concept of Industry 4.0. The methods used: application of cryptographic hash functions to the components (content and metadata) of an electronic document, the results of which are calculated using the binary Merkle tree type in combination with the chain data recording technology. Results of the study: the concept of "integrative electronic document" was introduced, a new structure of the electronic document was proposed, which made it possible to reduce the duration of its verification, and as a result, reduce the risk of destructive impacts on the automated information system.
- Podvalny S., Vasiljev E. Evolutionary methodology for multi-alternative control of complex systems
The article presents the results of studies devoted to the property of multi-alternative structure and functioning of complex biological systems. The purpose of the work is: generalization of these results in the form of an evolutionary methodology of multi-alternative control of large artificial systems, identification of the place of this methodology among known cybernetic principles of control, and determination of its capabilities in practical implementation. It is noted that the relevance of the above-mentioned generalization is determined by the urgent need to systematize various areas within the framework of cybernetics itself as a science. The cybernetic basis of the methodology of multi-alternative control is revealed, consisting in the reproduction of evolutionary mechanisms of living systems that go beyond the mechanism of natural selection and are traditionally considered as a property of the diversity of these systems. Based on the analysis of the content of these mechanisms, fairly simple principles of the proposed methodology are formulated: the principle of diversity and separation of functions, the principle of multi-level structure and the principle of modularity. The constructive nature of these principles is shown, directly indicating the methods and ways of their practical implementation. A generalized model of a multi-alternative control system is presented, and a description of its functional units is given. The system-forming role of the multi-alternative control methodology in relation to a number of basic cybernetic principles of control of false objects is shown, consisting in identifying the general evolutionary content of these principles. Specific examples of the application of the methodology for the synthesis of control systems for various objects are considered, and its high efficiency is demonstrated.
- Yurchenkov I. An efficient method for numerical solution of volume integral fredholm equations for acoustic wave propagation modeling problems
The purpose of the research is to develop a numerical scheme using iterative methods for solving systems of equations for solving bulk acoustic problems with inhomogeneous refraction index. The paper presents a formulation of the acoustic wave propagation problem in the form of a volume integral Fredholm equation of the second kind. A structured volume rectangular mesh is used to discretize the problem for the purpose of subsequent numerical solution. Using discretization, the problem formulation is reduced to a discretized operator in the form of a system of equations with a large number of variables and an operator matrix of high dimensionality. Taking into account the peculiarities of the integral kernels of the Helmholtz equation in integral form, numerical methods for solving the systems of equations using modifications of the matrix-vector multiplication of Toeplitz matrices by a vector based on the fast discrete Fourier transform are given. Numerical results of a set of programs for modeling propagation realizations of a plane wave model in a volumetric medium with inhomogeneous refraction index are demonstrated. Special attention in this paper is paid to the possibility of fast solution of mathematical physics problems on a structured grid of high dimensionality, which will allow us to consider the features of the solution on complex inhomogeneous boundaries, as well as to simplify the approximation of the solution. Finally, conclusions will be drawn about the quality of the obtained solutions on different examples of inhomogeneities of the considered volume domain.
- Romanenko V. Optimization of aircraft assignment to airlines with fuzzy initial data
A variant of the problem of optimal assignment of aircraft of specified types and numbers on a given airline network has been solved. The distribution of aircraft by airline is one of the key problems determining the efficiency of an air transport company. The considered task is to determine for each airline the weekly number of aircraft flights, which ensures the maximum economic effect of passenger transportation. The novelty of the problem statement lies in the fact that the levels of demand for passenger transportation are not fully defined expertly set fuzzy values, which corresponds to the stage of preliminary schedule design. Optimization of aircraft assignment by airlines is formulated as an integer mathematical programming problem with a fuzzy criterion and clear constraints. Thanks to the use of the defuzzification technique, the fuzzy problem is reduced to an ordinary mathematical programming problem solved by the available effective methods based on accessible software. Using the IBM ILOG OPL software package, the solution of model examples of the problem in fuzzy and "crisp" formulations was obtained. The comparison revealed significant differences between the most significant results of solving the optimization problem in fuzzy and "crisp" formulations, which indicates the expediency of taking into account the fuzzy uncertainty of the initial data.
- Rusakov K. Bayesian model for feature representation fusion in person re-identification
This paper addresses the problem of person re-identification in surveillance systems based on the analysis and integration of heterogeneous descriptive features. Unlike traditional approaches relying on a single biometric modality, a general-purpose probabilistic method is proposed to combine features derived from various sources. The method is based on Bayesian inference and models each feature as a random variable following a multivariate normal distribution. Parameters of the distributions are estimated from the training data. Decision making is performed by maximizing the posterior probability of identity given the available evidence. To extract features, transformer-based architectures with attention mechanisms are used, ensuring robustness to visual noise and viewpoint variation. The proposed model is compared with classical approaches based on linear combination of feature vectors. Experiments conducted on an open re-identification dataset demonstrate that the Bayesian scheme improves recognition accuracy and remains effective in cases of partial information loss. Moreover, the method provides a quantitative confidence score associated with each decision, making it particularly suitable for deployment in safety-critical environments such as automated video surveillance and access control systems.
- Gasanov I. The project of an order distribution system within the association of manufacturers through multiple auctions
The description of the project, presented in the article " The project of the order distribution system within the association of manufacturers through multiple auctions " // Upravlenie bol’shimi sistemami. – 2024. – Iss. 112, is ongoing. It explores the network interaction scheme within an association of companies engaged in the assembly production of a fixed set of products. The production process is represented as a directed acyclic graph, with the vertices corresponding to the components produced by the association’s members. To assemble lower-rank parts, higher-rank parts are used. Interaction is based on a system of multiple local auctions through which the distribution of production for each new order is carried out among the association’s member companies. If the previous work provides a brief overview of the project and outlines the issues related to its implementation, the current paper offers a detailed analysis of the proposed scheme, suggesting rules that participants should follow when making decisions. The paper examines the problem of rational price selection by the participants for the products they manufacture. In conclusion, the risks associated with the project's implementation are highlighted, and it is suggested that the effectiveness of the scheme be studied through computer simulation. The paper also discusses how an appropriate computer model can be built.
- Buzikov M., Petelina I., Krassotkin S., Ryzhov M., Kozitsin I. Forecasting the dynamics of public opinion based on longitudinal data of high granularity: the abelson model, regression models, and ensembles of models
We consdier the problem of forecasting the dynamics of public opinion based on longitudinal data of high granularity gleaned from the social network VKontakte. This problem was suggested to the participants of the Hackathon "UBS Challenge'2024" as one of the leisure events of the XX All-Russian School-Conference of Young Scientists "Management of Large Systems" (UBS), held in Novocherkassk in 2024. This paper is devoted to a detailed description of the Hackathon and the solutions proposed by its participants. For a sample of N = 1 648 829 users, based on two granular snapshots of their opinions taken six months apart (in February and July 2018), participants have to elaborate on a forecast of the distribution of public opinion in December 2018. The participants also had the information about the structure of friendship ties between users. We report that the highest accuracy was achieved by an ensemble of two models - the Abelson model, enhanced by estimating users' social power via the eigenvector centrality measure, and the constant trend model.
- Ovchinnikov P., Tkachev A., Miroslavskaya M. Using a hierarchical multi-variable regression model for the purpose of analysis and forecasting agricultural indicators
The article presents a methodology for determining the latent parameters of a multi-level multifactor regression model and ways of using the model using the example of forecasting the dynamics of indicators reflecting the functioning of agricultural production: grain crop yield and feed wheat consumption. The relevance of the model is due to the possibility of using it for forecasting the main output indicator (the first level of the model) and its intermediate components (subsequent levels of the model). The article processes statistical data, applies the method of regression analysis of information, and plots the results of modeling using MS Excel and the Python programming language development environment. The model is built on the basis of a hierarchical dependence of the first and subsequent levels, in which the input data of the output indicator are grouped as individual or common parameters of linear dependencies of intermediate variables. As a result of testing the model, data on grain crop yields were obtained depending on the type of fertilizer application and the corresponding shares of areas according to the Russian Federation as a whole and the Rostov Region, in particular, a yield forecast for three years was made, and a comparison with the results of applying factor analysis was given. In determining the consumption of feed wheat, data on the volume of net wheat consumption and the volume of wheat processed into compound feed were obtained.
- Vytovtov K., Gladkikh T. Algorithm for identification of water surface pollution for geoinformation systems
The article considers the urgent problem of detection of oil and oil products on the water surface, which is of crucial importance for ecological monitoring of water resources. The growth of water bodies pollution with oil products necessitates the development of effective methods for their detection and assessment of the ecosystem state. This paper presents a new analytical technique based on the study of the spectra of reflected sunlight, which allows for the high-precision detection of oil pollution. The authors obtained analytical expressions for the indices of spectral brightness coefficients, which were subsequently used in geographic information systems (GIS). These indicators help in processing and interpreting data obtained by remote sensing, significantly simplifying the process of monitoring and analyzing the state of water bodies. The method has proven its effectiveness in various conditions and can be adapted for use in real time. The research results contribute to the improvement of environmental monitoring methods and provide more reliable protection of water resources from pollution. In addition, the study considers the potential integration of this method with other environmental monitoring systems to improve the accuracy and efficiency of pollution detection. Thanks to these improvements, the proposed methodology not only allows for the detection of oil spills, but also helps in their management and the reduction of negative consequences associated with oil spills.
- Fedorova E., Tyulenina Y., Meloshnikova N. Mathematical modeling of hybrid energy systems using queueing theory
In the paper, a new mathematical approach for assessing the efficiency of hybrid energy system, using alternative energy sources (solar panels, wind turbines) based on queueing theory is proposed, which allows to consider into account the stochastic nature of natural processes. As a mathematical model of a hybrid energy system using an alternative (non-permanent) energy as one of the source of electricity, we propose a queueing system with two units of servers, one of which is non-permanent and limited. A three-dimensional Markov random process is studied. Using the initial moments method, formulas for stationary characteristics are derived. A numerical analysis of the system characteristics dependency on input parameters is performed. An example of assessment of the efficiency of using solar energy for personal needs based on statistical data is presented.
- Tislenko T., Semenova D. Development of an adaptive traffic light control system using markov decision processes
The paper presents the results of development of the MARLIN24 software suite, designed to implement adaptive control of traffic light systems. The primary objective of the development is to optimize the operation of traffic signals in order to minimize the total time vehicles spend within the detection zones of optical sensors. The architecture of the software suite comprises three principal modules: the adaptive control module, the traffic flow simulation module, and the validation module, complemented by an additional visualization module. The adaptive control module integrates four control approaches: fixed-time planning, uncoordinated reinforcement learning, coordinated multi-agent reinforcement learning, and phase duration control based on a MISO fuzzy logic controller (Multiple Input Single Output, MISO). Traffic flow simulation for performance evaluation is conducted via a microsimulation module utilizing the "Intelligent Driver Model" (IDM). The validation module employs copula functions to generate realistic optical sensor data reflecting actual traffic conditions, with marginal distributions derived from historical traffic intensity data collected during 2019-2020. The MARLIN24 software suite facilitates the analysis and comparison of multiple traffic control models on real-world sections of the road network in Krasnoyarsk under various conditions.
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