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This paper presents a novel approach to morphological contrast sharpening of image using the multilevel toggle operator. The concept presented here is a generalization of toggle based contrast operator for gray-level images. The multilevel toggle operator is used to enhance the contrast of multivalued images. In order to perform necessary morphological operations the modified pairwise ordering (MPO)...
This paper presents a proposal of a new control method of the switched reluctance motor (SRM) in the low-speed range. The proposed method limits the maximum value of SRM drive supply current. The application of this method results also in improvement of the drive efficiency compared to the classical current control method, so it can be applied to control switched reluctance motors designed to the...
The aim of this paper is developing an exact solution for the problem of axisymmetrical flow of unsteady motion of micropolar fluid in the half-space when the shear stresses are given on the boundary. The Laplace-Hankel transform technique is used to solve this problem. Some physical quantities such as velocities, pressure and microrotations are obtained and illustrated numerically.
An enhancement to the previously developed repetitive neurocontroller (RNC) is discussed and investigated in the paper. Originally, the time-base generator (TBG) has been used to produce the only input signal for the neural approximator. The resulting search space makes the dynamic optimization problem (DOP) of shaping the control signal solvable with the help of a function approximator such as the...
A new approach to the realization problem for fractional discrete-time linear systems is proposed. A procedure for computation of fractional realizations of given transfer matrices is presented and illustrated by numerical examples.
The main aim of this article is to review the existing state of art concerning the complete controllability of semilinear dynamical systems. The study focus on obtaining the sufficient conditions for the complete controllability for various systems using the Banach fixedpoint theorem. We describe the results for stochastic semilinear functional integro-differential system, stochastic partial differential...
In the paper, the analytical forms of fractional order derivatives of sinusoidal function according to definitions of Riemann - Liouville and Caputo are presented. To determine the analytical form of the integrals appearing in definitions of derivatives of fractional order the Lommel functions from hypergeometrical functions family were applied. With the use of properties of the derivatives of fractional...
Unscheduled power flows are a serious problem for the Central and Eastern Europe (CEE) region. One method of reducing these undesirable flows relies on the use of phase shifting transformers (PSTs). This paper presents how the installation of PSTs on the Polish-German and Czech-German borders affects cross-border power flows in the CEE region, as well as interactions between these devices. The essential...
This paper introduces a new algorithm of trajectory reproduction and trajectory tracking for nonholonomic systems. The endogenous configuration space approach is employed as a guideline in the algorithm derivation. The derivation uses a trajectory reproduction error, which is an integral of the difference between the resultant trajectory and the desired trajectory over the motion horizon. Such a definition...
Problems concerning electrical power quality and especially estimation of costs required for reduction of higher harmonics in power network voltage and current time waveforms have been considered in the paper. The application of active power filters to reduction of higher harmonics has been analysed taking into account, in particular, the necessary investment costs. Two goal functions have been used...
The stability problem of continuous-time linear fractional order systems with state delay is considered. New simple necessary and sufficient conditions for the asymptotic stability are established. The conditions are given in terms of eigenvalues of the state matrix and time delay. It is shown that in the complex plane there exists such a region that location in this region of all eigenvalues of the...
Various models of a projectile in a resisting medium are used. Some are very simple, like the “point mass trajectory model”, others, like the “rigid body trajectory model”, are complex and hard to use, especially in Fire Control Systems due to the fact of numeric complexity and an excess of less important corrections. There exist intermediate ones - e.g. the “modified point mass trajectory model”,...
Factional Discrete-time linear systems with fractional different orders are addressed. The Weierstrass-Kronecker decomposition theorem of the regular pencil is extended to the descriptor fractional discrete-time linear system with different fractional orders. Using the extension, method for finding the solution of the state equation is derived. Effectiveness of the method is demonstrated on a numerical...
In this paper, the stability problem of Furuta pendulum controlled by the fractional order PD controller is presented. A mathematical model of rotational inverted pendulum is derived and the fractional order PD controller is introduced in order to stabilize the same. The problem of asymptotic stability of a closed loop system is solved using the D-decomposition approach. On the basis of this method,...
The free vibration analysis of homogeneous and isotropic circular thin plates by using the Green’s functions is considered. The formulae for construction of the influence function for all nodal diameters are presented in a closed form. The limited independent solutions of differential Euler equations were expanded in the Neumann power series using the method of successive approximation. This approach...
In this paper the combined effect of uniform rotation and AC electric field on the onset of instability in a horizontal layer of an elastico-viscous fluid stimulated by the dielectrophoretic force due to the variation of dielectric constant with temperature is studied. Walters’ (model B’) fluid model is used to describe rheological behaviour of an elastico-viscous fluid. The onset criterions for stationary...
This study aims to simulate and to analyze the elastic and the damage behavior of a reinforced metallic liner (RML) by means of a computational tool, in order to aid in the design of high specific-stiffness and -strength barrels for heavy-duty hydraulic applications. Case studies for the program validation are undertaken using an AISI 1026 or St52.3 steel tubing reinforced with a polymeric composite...
The critical monotonic strain of Ni-W and MoS2(Ti,W) coatings on steel substrates was studied. The idea of axisymmetric bending test (called here as coin bending test) limited to monitoring of the coating failure was used. Experiments revealed mechanism of the coating failure, as cracking initiated from coating surface defects and/or substrate was demonstrated using indentation technique. By pushing...
Functionally graded materials (FGMs) belong to a new, continuously developing group of materials, finding application in various branches of industry. The idea of freely designing their construction profile, restricted only by the available manufacturing techniques, enables obtaining materials with composition and structure gradients having unprecedented properties. In this paper, selected results...
The article presents that in the circuits of electrical signals belonging to the L1-impulses space or periodic signals space, real distribution of electrical currents occurs which does not meet the principle of minimum energy losses. The paper presents a solution of this problem by using the control system in the form of current-dependent voltage sources entering it into a meshes set of a complex...
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