


卷 78, 编号 4 (2017)
- 年: 2017
- 文章: 17
- URL: https://ogarev-online.ru/0005-1179/issue/view/9002
Nonlinear Systems
Attraction domain estimate for single-input affine systems with constrained control
摘要
Nonlinear single-input affine systems represented in a canonical (normal) form are considered. The control resource is assumed to be constrained. For a closed-loop system obtained by applying a linearizing feedback, the problem of finding an estimate of the attraction domain is set. A method for constructing an ellipsoidal estimate that is based on results of absolute stability theory is suggested. Construction of the estimate reduces to solving a system of linear matrix inequalities. The discussion is illustrated by numerical examples.



Model containing coupled subsystems with oscillations of different types
摘要
Consideration was given to an autonomous model containing coupled subsystems (MCCS) and, in the absence of couplings between the subsystems, falling down into systems of ordinary differential equations. It is assumed that the subsystems admit different types of nondegenerate single-frequency oscillations. Solved were the problems of oscillations in MCCS, their stability, and stabilization of MCCS oscillation by smooth autonomous coupling controls. It was shown how the developed theory is applied to the coupled Duffing and Van der Pol oscillators.



Methods of subdifferential and hypodifferential descent in the problem of constructing an integrally constrained program control
摘要
For an object whose dynamics obeys a system of ordinary differential equations, application of the methods of subdifferential and hypodifferential descent to the problem of program control of object dynamics was illustrated.



Methods of averaged optimization in the problem of extending the rate of sliding of the right side discontinuity surface
摘要
For the problem of extending the rate of sliding of a dynamic system with discontinuous right sides, a generalization of the A.F. Filippov method of speed averaging was proposed. In the multidimensional case, this extension was shown to be reducible to the averaged problem of nonlinear programming. The methods of averaged optimization were shown to be applicable to calculation of the sliding rate. Consideration was given to the problems with different dimensions of the vector of admissible rates and number of control discontinuity surfaces.



The parameter functionalization method for the problem of saddle-node bifurcations in dynamical systems
摘要
We propose new sufficient conditions for saddle-node bifurcations in one- and twoparametric dynamical systems obtained with the parameter functionalization method, derive asymptotic formulas for the resulting solutions, and analyze their stability. As an application, we consider the synchronization problem for periodic oscillations of an autonomous Van der Pol generator under an external harmonic influence.



Stochastic Systems, Queueing Systems
On the lower bound of the anisotropic norm of the linear stochastic system
摘要
The anisotropic norm of the linear discrete time invariant system is the measure of the system output sensitivity to a random input with the mean anisotropy bounded by some nonnegative value a. The mean anisotropy characterizes the degree of predictability of the stochastic signal. The anisotropic norm of a system is the induced norm with the extreme cases of H2 norm and H∞ norm, respectively, under a → 0 and a → ∞. The lower bound of the anisotropic norm of the linear discrete time invariant system was established in the present paper using the methods of linear algebra.



Robust and Adaptive Systems
Dynamical properties of an adaptive control system with a nonlinear reference model. I
摘要
We show the results of solving the problem of constructing an adaptive control system with nonlinear reference model for a nonstationary dynamical object with a nonlinear actuator. To analyze the dynamical properties of a nonlinear nonstationary control system we use the method of pointwise transformations. We show the results of analysis and mathematical modeling of the considered control system with the adaptation circuit switched off.



System Analysis and Operations Research
Elements of dynamic programming in local improvement constructions for heuristic solutions of routing problems with constraints
摘要
We consider methods for solving routing problems with precedence constraints that use iterative modes based on Bellman insertions while recomputing precedence constraints of the original problem; we assume that the dimension of the latter is sufficiently large, which does not let us, due to complexity of computations, immediately apply dynamic programming in the “global” version.



Control in Social Economic Systems, Medicine, and Biology
Discrete-event diagnostic model for a distributed computational system. Merging chains
摘要
We consider synthesis problems for a discrete event model in a real time distributed computational system. The model reflects information exchange events between software units of the system and is intended to construct special test sequences that detect faults in these exchanges. We propose a version of the model that allows for a reduction in the relative volume of diagnostic information transmitted to diagnostic tools.



Intellectual Control Systems
How the structure of system problems influences system behavior
摘要
We consider the possibility to explain manifestations of collective intelligence via the presence of structure in the set of tasks may being fulfilled. A distributed system corresponds to a lattice of tasks that the system can fulfill. On this lattice, we define an external multiplication operation for lattice elements and respective operations of linear logic. The implication operation is used to choose the version of system reconfiguration, i.e., choose an executor for a new task. We show that this choice is to a large extent defined by the structure of the lattice of tasks and the definition of the multiplication operation on it. The proposed reconfiguration method is applied to an example of operation for a group of janitor robots.



Computer-Aided Information Control Systems, Process Control Systems
Hierarchical robust systems for magnetic plasma control in tokamaks with adaptation
摘要
We consider synthesis and modeling of hierarchical robust magnetic control systems for plasma in tokamaks with adaptation of the magnetic axis’ vertical position. The studies were done for ITER (Cadarache, France) and Globus-M (St. Petersburg, Russia) tokamaks. Our original synthesis method ensures an improvement in performance for the shape of the plasma by resolving the contradiction between position and plasma shape via adaptation in a hierarchical system. Numerical modeling of synthesized control systems on multivariable linear models of plasma and nonlinear plasma-physics code DINA that unites basic equations of plasma dynamics in a magnetic field has shown the efficiency of the proposed approach and a possibility to apply it in a physical experiment.



Control Sciences
Evasion of a moving object from detection by a system of heterogenous observers in the threat environment
摘要
This paper presents a formalization and the results of solution for the problem of moving object evasion from detection on a plane. Detection is performed by a system of heterogenous stationary observers by the last transmitted signals of the primary and reflected (secondary) fields in the passive and active modes, respectively. Simulation results are given.



Automation in Industry
Structural and parametric identification of soft sensors models for process plants based on robust regression and information criteria
摘要
Approach to the solution of a problem of structural and parametrical identification of models of the soft sensors (SS) of technological plants on the basis of robust regression and information criteria is proposed. The robust regression is used for model parameter estimation, and choosing the best model structure in the sense of information criteria. SS is developed by means of the proposed approach which was tested in control systems for optimization of the process operation of gas separation section of fluid catalytic cracking unit of “OJSC Gazpromneft-Omsk Refinery.”



Large Scale Systems Control
A metric for total tardiness minimization
摘要
In this paper we consider the NP-hard 1|rj|ΣTj scheduling problem, suggesting a polynomial algorithm to find its approximate solution with the guaranteed absolute error. The algorithm employs a metric introduced in the parameter space. In addition, we study the possible application of such an approach to other scheduling problems.



Sensors and Systems
Estimation of the maximum correlation coefficient using Bernstein copula
摘要
In this paper, the estimation of a nonlinear stochastic dependence between signals in information-measuring and control systems is considered. The maximum correlation coefficient and corresponding optimal transformations of the signals are estimated using the Bernstein approximation. Some basic concepts of the copula theory are discussed. Main calculation formulas for the maximum correlation coefficient in the case of a degenerate stochastic kernel are presented. An estimation algorithm for the maximum correlation coefficient and corresponding optimal (nonlinear) transformations of random signals is proposed. An example of correlation estimation for random signals is given.



Mathematical Game Theory and Applications
The pursuit-evasion game on the 1-skeleton graph of a regular polyhedron. I
摘要
We consider a game between a group of n pursuers and one evader moving with the same maximum velocity along the 1-skeleton graph of a regular polyhedron. The goal of the paper is finding, for each regular polyhedron M, a number N(M) with the following properties: if n ≥ N(M), the group of pursuers wins, while if n < N(M), the evader wins. Part I of the paper is devoted to the case of polyhedra in ℝ3; Part II will be devoted to the case of ℝd, d ≥ 5; and Part III, to the case of ℝ4.



Altruistic behavior in a nonantagonistic positional differential game
摘要
We consider a two-person nonantagonistic positional differential game (NPDG) whose dynamics is described by an ordinary nonlinear vector differential equation. Constraints on values of players’ controls are geometric. Final time of the game is fixed. Payoff functionals of both players are terminal. The formalization of positional strategies in an NPDG is based on the formalization and results of the general theory of antagonistic positional differential games (APDGs) (see monographs by N.N. Krasovskii and A.I. Subbotin [3, 4]). Additionally, in the present paper we assume that each player, together with the usual, normal (nor), type of behavior aimed at maximizing his own functional, can use other behavior types introduced in [2, 5]. In particular, these may be altruistic (alt), aggressive (agg), and paradoxical (par) types. It is assumed that in the course of the game players can switch their behavior from one type to another. Using the possibility of such switches in a repeated bimatrix 2 × 2 game in [5, 6] allowed to obtain new solutions of this game. In the present paper, extension of this approach to NPDGs leads to a new formulation of the problem. In particular, of interest is the question of how players’ outcomes at Nash solutions are transformed. An urgent problem is minimizing the time of “abnormal” behavior while achieving a good result. The paper proposes a formalization of an NPDG with behavior types (NPDGwBT). It is assumed that in an NPDGwBT each player, simultaneously with choosing a positional strategy, chooses also his own indicator function defined on the whole game horizon and taking values in the set {normal, altruistic, aggressive, paradoxical}. The indicator function of a player shows the dynamics of changes in the behavior type demonstrated by the player. Thus, in this NPDGwBT each player controls the choice of a pair {positional strategy, indicator function}. We define the notion of a BT-solution of such a game. It is expected that using behavior types in the NPDGwBT which differ from the normal one (so-called abnormal types) in some cases may lead to more favorable outcomes for the players than in the NPDG. We consider two examples of an NPDGwBT with simple dynamics in the plane in each of which one player keeps to altruistic behavior type over some time period. It is shown that in the first example payoffs of both players increase on a BT-solution as compared to the game with the normal behavior type, and in the second example, the sum of players’ payoffs is increased.


