Optimal Stabilization of Linear Stochastic System with Statistically Uncertain Piecewise Constant Drift

The paper presents an optimal control problem for the partially observable stochastic differential system driven by an external Markov jump process. The available controlled observations are indirect and corrupted by some Wiener noise. The goal is to optimize a linear function of the state (output) given a general quadratic criterion. The separation principle, verified for the system at hand, allows examination of the control problem apart from the filter optimization. The solution to the latter problem is provided by the Wonham filter. The solution to the former control problem is obtained by formulating an equivalent control problem with a linear drift/nonlinear diffusion stochastic process and with complete information. This problem, in turn, is immediately solved by the application of the dynamic programming method. The applicability of the obtained theoretical results is illustrated by a numerical example, where an optimal amplification/stabilization problem is solved for an unstable externally controlled step-wise mechanical actuator.

Algorithm Synthesis of Controlling a Transport Unit of a Coextrusion Flexible Manufacturing Section for Processing Multicomponent Materials

The paper offers a mathematical model of the process of coextrusion flexible manufacturing section functioning. On the basis of dynamic programming method an algorithm of controlling transport unit of coextrusion flexible manufacturing system is developed. The objective of the current research is the development of the mathematical model of the flexible manufacturing complex for processing multicomponent materials functioning process, and construction of the algorithm of controlling a transport unit of a coextrusion flexible manufacturing complex for processing multicomponent materials on this basis. The paper offers the criterion of evaluating the quality of controlling the transport unit. The chosen variant of controlling the transport unit has to meet many requirements. This paper con-siders the issues connected with the search for an optimum algorithm of control-ling a transport unit according to the set criterion. Most works offer analytical models which are based on the assumption of the current processes’ stability. Real manufacturing conditions are characterized by the effect of numerous perturbing factors. Under such conditions the assumption of the current processes’ stability makes the obtained models almost untrue.

Optimal Image Based Information Hiding with One-dimensional Chaotic Systems and Dynamic Programming

Information hiding is a technology aimed at the secure hiding of important information into digital documents or media. In this paper, a new approach is proposed for the secure hiding of information into gray scale images. The hiding is performed in two stages. In the first stage, the binary bits in the sequence of information are shuffled and encoded with a set of integer keys and a system of one-dimensional logistic mappings. In the second stage, the resulting sequence is embedded into the gray values of selected pixels in the given image. A dynamic programming method is utilized to select the pixels that minimize the difference between a cover image and the corresponding stego image. Experiments show that this approach outperforms other information hiding methods by 13.1% in Peak Signal to Noise Ratio (PSNR) on average and reduces the difference between a stego image and its cover image to 0 in some cases.

The development of the system for arc nordugrid based grid-computing organization using virtual environments of the docker platform

The study of modern frameworks and means of using virtualization in a grid environment confirmed the relevance of the task of automated configuration of the environment for performing tasks in a grid environment. Setting up a task execution environment using virtualization requires the implementation of appropriate algorithms for scheduling tasks and distributed storage of images of virtual environments in a grid environment. Existing cloud infrastructure solutions to optimize the process of deploying virtual machines on computing resources do not have integration with the Arc Nordugrid middleware, which is widely used in grid infrastructures. An urgent task is to develop tools for scheduling tasks and placing images of virtual machines on the resources of the grid environment, taking into account the use of virtualization tools. The results of the implementation of services of the framework are presented that allow to design and perform computational tasks in a grid environment based on ARC Nordugrid using the virtual environment of the Docker platform. The presented results of the implementation of services for scheduling tasks in a grid environment using a virtual computing environment are based on the use of a scheduling algorithm based on the dynamic programming method. Evaluations of the effectiveness of the solutions developed on the basis of a complex of simulation models showed that the use of the proposed algorithm for scheduling and replicating virtual images in a grid environment can reduce the execution time of a computational task by 88 %. Such estimates need further refinement; it is predicted that planning efficiency will increase over time with an increase in the number of running tasks due to the redistribution of the storage of virtual images

Determination of optimal control of a vessel diesel engine during non-stationary traffic regimes

The high pressure fuel system is the fundamental system that forms the indicator of the minimum fuel consumption per unit of the vessel's path. The calculation of the optimal control of the vessel complex with the main diesel engine is performed according to the criterion of the minimum fuel consumption per unit path at a given average velocity of the vessel. The propulsion of a vessel with a main diesel engine is described by equations. The equations contain a significant number of parameters, the reduction of which is performed by introducing dimensionless quantities, followed by bringing the equations into dimensionless forms. This made it possible to present a solution to the optimal control law for the main vessel diesel engine as part of the vessel complex. Optimal control of the vessel complex under stormy navigation conditions has been investigated. The calculations of the control law of the vessel complex, which ensure the movement of the vessel with the maximum average velocity in conditions of stormy navigation, are presented. It is determined that the established law of control of the vessel complex ensures the minimum fuel consumption per mile at a given average velocity of its movement. The influence of a high-pressure fuel system on the optimal control of a vessel diesel engine has been investigated. Thus, the calculated studies indicate that for all values of the parameters of the vessel complex according to the law of control of the fuel system Ф=а+b∙C2(τ), they give fuel savings up to 6% per unit of way in comparison with the law of control of the vessel complex Ф=а+b∙(c1(τ)/c2(τ)). The obtained ratios during modeling and optimal control of the main diesel engine of the vessel complex allow using the dynamic programming method to analyze the fuel consumption per unit path with optimal control compared to the corresponding constant control

Force control in girder-cable systems

The object of the study is the forces in the beam-cable systems. The introduction of these systems in construction is associated with the task of creating a pre-stress in order to regulate the stress-strain state of the beam-cable system as a whole. Prestressing will make it possible to rationally use high-strength materials in the structure, and to design the structure economically. When designing girder-cable-stayed structures of bridge spans, it is necessary to determine the sequence of stresses of the structural elements-shrouds in order to regulate the forces in the beam element of the structure. This problem is considered in this article. The dynamic programming method is used to regulate the stress-strain state of the system by pulling the shrouds in the optimal sequence. To solve the problems, formulas for the output value and the optimality criterion, as well as the matrix, are given. As a result, the values of the output values of interest at all stages of the tension of the shrouds are found.