Vol 80, No 2 (2019)

We propose a control algorithm for linear objects with a input time-delay in the presence of external disturbances. First, the state predictor and the disturbance predictor are used to synthesize the algorithm. The state predictor performs asymptotic prediction of the state vector, therefore, the closed-loop system contains the state delay. Thus, there exist an upper bound of the delay for which the closed-loop system remains stable. The disturbance predictor is designed under the assumption of the existence of bounded derivatives of the disturbance. Further, the state and disturbance subpredictors are constructed in the form of a serial connection of the corresponding predictors performing multi-step prediction. Sufficient conditions for the stability of the closed-loop system are obtained in the form of feasibility of linear matrix inequalities. We show simulation results that illustrate the effectiveness of the proposed scheme compared to some existing ones. Numerical examples show that the obtained sufficient conditions guarantee the stability of the controller based on the subpredictors with a larger delay than a controller based on predictors.

Consideration was given to the problem of functional diagnosis of the nonlinear dynamic systems by the nonparametric method distinguished for the fact that the values of some parameters of the diagnosed system need not to be known. An approach was proposed enabling fault isolation. Established were the necessary and sufficient conditions for system transformed into the canonical form required for application of the nonparametric method at diagnosis of the given nonlinear system.

We consider a control problem over an infinite time horizon with a linear stochastic system with an unstable asymptotically unbounded state matrix. We extend the notion of anti-stability of a matrix to the case of non-exponential anti-stability, and introduce an antistability rate function as a characteristic of the rate of growth for the norm of the corresponding fundamental matrix. We show that the linear stable feedback control law is optimal with respect to the criterion of the adjusted extended long-run average. The designed criterion explicitly includes information about the rate of anti-stability and the parameters of the disturbances. We also analyze optimality conditions.

We consider one of the tasks of managing the redundancy in a heterogeneous integrated complex of technical equipment defined by a system of linear discrete equations. The task consists in testing a predefined configuration of the complex for implementability. We formulate both sufficient and necessary and sufficient conditions for testing configurations formalized by interface matrices. We illustrate the application and efficiency of the proposed testing conditions with an example based on a redundant aircraft motion control system.

We propose a new model for the formation of a public-private partnership mechanism, formulated as a bilevel Boolean programming problem. We show that this task is ∑₂^P-hard in both optimistic and pessimistic forms. We develop a stochastic iterative algorithm for solving this problem. We also present computational experiments on real information that demonstrate the capabilities of the proposed approach.

A set of jobs has to be processed on parallel machines. For each job, there are given a release time and a due date and the job must be processed no later than its due date. If the job will be completed no later than the given due date, a benefit will be earned. Otherwise, this job will be rejected and the benefit will be discarded. The criterion under consideration is to maximize the weighted sum of the benefits and the number of jobs processed in time. Some properties of the objective function are found which allow to construct a optimal schedule. We develop a simulated annealing algorithm, a tabu search algorithm, and a genetic algorithm for solving this problem. The developed algorithms were tested on moderate and large instances with up to 500 jobs and 50 machines. Some recommendations are given showing how to use the obtained results and developed algorithms in production planning.

We propose a new approach for feature selection. The proposed approach is based on a combination of random and heuristic search strategies. The solution is represented as a binary vector whose dimension is determined by the number of features in the dataset. New solutions are generated at random using a normal and uniform distribution. The heuristic underlying the proposed approach can be formulated as follows: the chance of a feature to get into the next generation is proportional to the frequency of this feature appearing in previous best solutions. The proposed approach has been tested on several datasets from the KEEL repository. We also show an experimental comparison with other methods.

This paper proposes metaheuristic interval methods of global constrained optimization and their software implementation. Three methods are considered: average path endings, stochastic grid, and interval scatter search. The methods are applied to optimal program control design for nonlinear deterministic discrete and continuous systems. As an application the problem of three-dimensional interception is solved and a comparative analysis of efficiency is presented.

Using a simplified multistage bidding model with asymmetrically informed agents, De Meyer and Saley [17] demonstrated an idea of endogenous origin of the Brownian component in the evolution of prices on stock markets: random price fluctuations may be caused by strategic randomization of “insiders.” The model is reduced to a repeated game with incomplete information. This paper presents a survey of numerous researches inspired by the pioneering publication of De Meyer and Saley.

Critical importance of the task ensues from the lack of any tools and techniques in domestic industry for the diagnostics of discharge parameters directly on a spark plug. This interferes with rational selection of ignition system parameters, optimization of ignition processes in ignition chambers and ensuring reliable start of aviation engine. Such equipment is necessary for research institutions and engine firms involved in ignition system engineering, manufacturing, testing and installation.