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 Выпуск 75
- Kuznetsov A. Dynamic model of the communication system of a group of agents
We construct a model of message delays in the mobile communication network of agents. In the model, the connectivity and types of channels between agents change over time. Agents move around the terrain, on which there are obstacles of various impassability that impede communication between agents in various degree. We use a cellular automaton model for the movement of agents along the terrain. Agents are the vertices of the communication graph. Each agent owns a set of communication devices. The edges of the communication graph are the communication channels organized by communication devices of agents located at the vertices of the graph. Channels of different types have a different limiting range and permissible height of obstacles between agents. If there is an obstacle between agents that excludes communication on the existing communication channel, the communication channel is changed to the more suitable one, taking into account the capabilities of the agents. Each agent has a message schedule, and each communication channel has the maximum bandwidth. When sending messages by several agents simultaneously using one communication channel, the reduction in the capacity of this channel is taken into account. We also consider the relaying of a message by a chain of agents. We simulate a traffic dynamic in telecommunication channels of the system with agents motion and possible channel breaks and changes. Further, we discuss different ways of the model's application.
- Semenov D. Synchronization control of two coupled non-identical hindmarsh-rose systems
The problem of controlled synchronization between two coupled non-identical Hindmarsh-Rose systems, each of which describes the behavior of a biological neuron, was considered. The importance of solving this problem is caused by a variety of medical and biological research that determines the correlation between the certain diseases of the nervous system (such as epilepsy) and pathological synchronization between neurons in the brain areas. Thus, the ability to control synchronization between neurons is a promising method for the therapy of epilepsy and has been actively used in medical practice. Obviously, the development of this method of therapy requires the usage of qualitative mathematical tools. Our approach is based on the applying of the tools of control theory. In addition, it is necessary to take into account an inaccuracy of the modern neural models. In order to do this, we propose to consider this inaccuracy in the form of the continuous functions which describe the disturbances. Thus, using the control law, which was suggested in this article, and abiding by the theorems, which were formulated here, it is possible to achieve synchronized behavior of the systems in the conditions of absence and presence of the disturbances. The results were proved and confirmed by simulations.
- Nadezhdin I., Goryunov A., Manenti F. Control systems of a non-stationary plant based on mpc and pid type fuzzy logic controller
Currently in the industry, at any stage of production process there is a high level of automation. As a rule, the majority of technological processes, occurring today in the industry, are non-stationary control objects. In order to improve the efficiency of automatic control system of non-stationary control object, researchers around the world, doing research, trying to combine the standard PID regulator with fuzzy adaptive controller. As a rule, setting a fuzzy controller is made based on the Mamdani controller. Also, recently, for the control of non-stationary control object are widely used controllers on the basis of a predictive model. The purpose of this paper is the comparative analysis of automatic control systems with PID regulator based on fuzzy logic and regulator on the basis of a predictive model (MPC-controller). In the course of research, stepwise disturbance of a certain amplitude and duration were applied to the control object. As a result, transient processes were obtained and quality indicators were determined. By comparing and analyzing the results obtained, a conclusion was made about the advantages of one controller over another.
- Gorbatenko D., Semenov A. Counteraction to conspiracy in discrete dynamical models of computers network
The paper studies the problem of counteracting the collusion of subjects in computer networks. In real world situations the goal of the collusions is to obtain some access rights between two network subjects. Within the proposed model, collusion is considered as a dynamic process taking place at discrete time. An original network is associated with a discrete dynamic system (DDS), in which collusion corresponds to a sequence of transitions between states. Collusion is successful if as a result of a sequence of steps the access rights are transferred from one particular subject to another. A counteraction to such collusion is achieved by deactivating some nodes. In a real network a deactivation corresponds to reducing access level between subjects. Deactivation of several nodes induces a new DDS. A final state of such DDS is a stationary point. If in this point the access rights are not transferred between selected subjects, then deactivation successfully blocked collusion. In the paper we consider a problem of finding minimal deactivating set. It is reduced to Boolean satisfiability problem and solved using state-of-the-art SAT solvers. We use the Take-Grant model of computer security because it is one of the most simple and well-studied models.
- Davydov V. Combining the counter-plan method and the inverted priorities method for distribution of the motivation fund for scientific laboratories
An incentive model for an organizational system (OS) agent is considered, using a combination of the method of inverted priorities and a modified counter-plan method. The resulting model motivates the agent to report the planned KPI value, which coincides with the agent's forecast and at the same time stimulates the agent to submit an adequate application for the resource. The model allows the OS center to allocate a dedicated resource to run each KPI between agents so that in addition to reporting adequate plans, agents are committed to their implementation. Restrictions are imposed on the model parameters, in which the choice of an agent equal to its own forecast is a dominant strategy (DS), provided that the agent submits the optimal (according to the method of inverted priorities) requests for the resource. It is proved that such a choice for all OS agents is an equilibrium in DS. The procedure for determining the planned KPI values for OS agents and resource allocation between agents is described. The model parameters determined by the OS center, taking into account the imposed restrictions, allow selecting the required priorities for agent motivation and distributing a motivational fund in accordance with the priorities identified by the center. An example of the application of the model for stimulating scientific laboratories for the preparation of students is given.
- Zasukhin S. Determining evaporation as a solution of the optimal control problem
The problem of determining evaporation is stated as an optimal control problem. The controlled process of vertical water transfer in soil is described by one-dimensional nonlinear parabolic equation. The daily evaporation is a control and, the objective function is the mean-square deviation of calculated values of the soil moisture from some prescribed values. As a result of finite difference approximation, the optimal control problem is reduced to a nonlinear programming problem. The problem obtained is proposed to be solved by the steepest descent method. The objective function gradient is computed using exact formulas of fast automatic differentiation. It is assumed that the prescribed values coincide with some solution of the direct problem on the set of comparisons of the calculated values and prescribed values of soil moisture. How does the type of this set affect the accuracy of the solution? Several variants of such a set are considered. The analysis of numerical solutions of the corresponding problems allows to choose the optimal variant in the sense of the accuracy of the solution and the number of measurements of the required soil moisture data.
- Kolodkina A., Maryasin O., Ogarkov A. Optimal control for building energy and comfort management of large multi-zone buildings
In this article, the problem of energy-efficient control of the indoor environment of large multi-zone buildings is considered. To solve this problem, it is proposed to use the hierarchical, distributed, predictive optimal control method (MPC approach). This method allows you to achieve a minimum of the global quality criterion and the implementation of restrictions for the whole system, taking into account the interrelationships between subsystems. When implementing a hierarchical distributed MPC-algorithm, there arises the problem of coordinated solution for the mathematical programming problems for each of the subsystems. To solve the global problem of mathematical programming, the authors propose a method based on the decomposition method via resource sharing. The authors prove that under certain assumptions on sets of admissible solutions for local problems, if the local optimization problems have a solution, then the coordination problem will have an admissible optimal solution. Numerical results are presented in order to illustrate the effectiveness of the proposed control strategy. As a result of comparison of various variants of the optimal control implementation, it is established that hierarchical distributed approach provides the best compliance with the limitations and the greatest energy saving. The availability of various types of energy resources allows, for example, in case of a sharp increase in the household needs consumption of thermal energy during peak hours, to increase the input of electricity to maintain the required microclimate.
- Skvortsov E., Shelekhova A. Beginning of theory of conceptual design with applications in aeronautical science and technology
The work presents key concepts of conceptual design, that are formulated in terms of set theory, vector analysis and general systems theory. The conception is understood as the combination of several principles that form the information-logical model of an artificial object. The principles are intentional convolutions of related information, the vectors of which are defined by ideas, and the content is defined by the components of the system. The concepts of the exosystem (the model of interaction with the environment) and the endosystem (the model of an separate object) are highlighted. Unity of the model is created by an active functional system, which in a documented form creates a project. The diversity of principles is expanded by the introduction of the principle of "form" along with the principles of «action» and «structure» of the object. The realizability of the object is provided by the technologies. The process of conceptual design is presented as a sequential activity aimed at eliminating uncertainties, which are caused by the complex nature of project information with an imaginary component. The proposed theory allows to manage the conceptual project, relying on the laws of mathematical logic. Formalized through this design decisions are strictly justified.
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