The paper presents a novel approach to solving a problem generally arising in studying dynamical systems, namely the problem of a system’s properties preservation under some transformation. Combining algebra, logic a...
The paper presents a novel approach to solving a problem generally arising in studying dynamical systems, namely the problem of a system’s properties preservation under some transformation. Combining algebra, logic and dynamics, the method of logical-algebraic equations (LAE-method) is developed, serving to synthesize criteria for preservation properties of systems connected by special type of morphisms. The LAE-method is applicable to various systems, but we focus on the case of discrete-event systems (DES), which are the systems that evolve in time due to the occurrence of some event sequences. We consider the issues of the LAE-method application to the reduction of supervisor for DES, the problems of DES basic properties, such as observability and controllability, preservation when sensor readings provide information about system’s state and it is available to a supervisor. Decentralized supervisory control is also addressed, in particular, the question whether local supervisors properties are inherited in a global supervisor.
The exciton spin dynamics are investigated both experimentally and theoretically in two-monolayer-thick GaAs/AlAs quantum wells with an indirect band gap and a type-II band alignment. The magnetic field induced circul...
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The exciton spin dynamics are investigated both experimentally and theoretically in two-monolayer-thick GaAs/AlAs quantum wells with an indirect band gap and a type-II band alignment. The magnetic field induced circular polarization of photoluminescence Pc is studied as function of the magnetic field strength and direction as well as sample temperature. The observed nonmonotonic behavior of these functions is provided by the interplay of bright and dark exciton states contributing to the emission. To interpret the experiment, we have developed a kinetic master equation model which accounts for the dynamics of the spin states in this exciton quartet, radiative and nonradiative recombination processes, and redistribution of excitons between these states as result of spin relaxation. The model offers quantitative agreement with experiment and allows us to evaluate, for the studied structure, the heavy-hole g factor, ghh=+3.5, and the spin relaxation times of electron, τse=33μs, and hole, τsh=3μs, bound in the exciton.
A description of the calculus of positively constructed formulas (PCF) and prover based on this calculus is considered. The PCF calculus has been developed by Russian scientists S.N. Vassiliev and A.K. Zherlov by an e...
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ISBN:
(纸本)9781467386456
A description of the calculus of positively constructed formulas (PCF) and prover based on this calculus is considered. The PCF calculus has been developed by Russian scientists S.N. Vassiliev and A.K. Zherlov by an evolutionary way in describing and solving controltheory problems. This calculus has features, which are applicable in controltheory. The described implementation of the prover uses several techniques and strategies to improve prover performance. The prover is being tested by means of solving problems from TPTP library. The usage of implemented inference search strategies is also commented in this paper.
Engineering of the compiled software is an important task in software engineering. One of the stages of the engineering technologies is a construction and analysis of a control flow graphs, which reflect a general str...
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Engineering of the compiled software is an important task in software engineering. One of the stages of the engineering technologies is a construction and analysis of a control flow graphs, which reflect a general structure of algorithms. The paper presents a technique for analyzing and visualizing the control flow graph of a compiled software. The analysis is based on semantically equivalent transformations of the original graph resulting in an abstract node that contains a hierarchy of isolated regions, which then associated with predefined templates resulting a graphical representation. The templates and additional signature data allow one to recognize the high-level programming structures and user statements to construct a flow-chart notation of the original program.
Formation stability problem for a team of autonomous underwater vehicles (AUV) with digital control is investigated. A leader-follower formation control algorithm for multi-AUV system is proposed. Feedback control sig...
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ISBN:
(纸本)9781509025435
Formation stability problem for a team of autonomous underwater vehicles (AUV) with digital control is investigated. A leader-follower formation control algorithm for multi-AUV system is proposed. Feedback control signal for the follower, which is piecewise constant, is computed on the basis of discrete measurements of the distance and the bearing angle to the leader. A discrete observer for estimation of the derivatives of the distance and the bearing angle are used to improve the control performance. The parameters of the controller and observer are synthesized using a digital controlsystem design method based on the vector Lyapunov functions that allows one to take into account the uncertainties of the plant, measurement errors, and control constraints. Numerical simulations are carried out to demonstrate the effectiveness of the proposed control scheme.
We shortly present results on development and employment of the software systems for computer-aided design of the spacecraft guidance. navigation and controlsystems – modeling, synthesis, nonlinear analysis, simulat...
We shortly present results on development and employment of the software systems for computer-aided design of the spacecraft guidance. navigation and controlsystems – modeling, synthesis, nonlinear analysis, simulation and graphic mapping of dynamic processes.
An application of the iterative hill climbing algorithm to the solution of inverse problems of underwater acoustics is discussed. Modal dispersion data extracted from a recording of a pulse acoustical signal is used a...
An application of the iterative hill climbing algorithm to the solution of inverse problems of underwater acoustics is discussed. Modal dispersion data extracted from a recording of a pulse acoustical signal is used as the input for the geoacoustic inversion procedure. The mismatch of the dispersion curves extracted from experimental data and computed from a given set of waveguide parameters is minimized over the parameters space. The solution of two test inversion problems is considered. It is shown that the iterative launches of the hill climbing algorithm allow to locate either the global minimum or a local minimum which is reasonably close to the former. In the latter case a reasonable estimate of the waveguide parameters is obtained.
We propose a hybrid approach, based on the combined use of genetic algorithms, methods and heuristics of local search, and ant colony optimization to solve the dynamic routing problem for a group of underwater robots....
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The exciton spin dynamics are investigated both experimentally and theoretically in two-monolayer-thick GaAs/AlAs quantum wells with an indirect band gap and a type-II band alignment. The magnetic-field-induced circul...
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The problem of numerical finding of a Nash equilibrium in a polymatrix game is considered. Such a game turns out to be equivalent to the solving a nonconvex optimization problem with a bilinear structure in the object...
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ISBN:
(纸本)9789616165457
The problem of numerical finding of a Nash equilibrium in a polymatrix game is considered. Such a game turns out to be equivalent to the solving a nonconvex optimization problem with a bilinear structure in the objective function. Special methods of local and global search for the 3-player game are proposed and investigated.
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