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A vehicle-track-soil dynamic interaction problem in sequential and parallel formulation

Janusz Kogut, Henryk Ciurej (2010)

International Journal of Applied Mathematics and Computer Science

Some problems regarding numerical modeling of predicted vibrations excited by railway traffic are discussed. Model formulation in the field of structural mechanics comprises a vehicle, a track (often in a tunnel) and soil. Time consuming computations are needed to update large matrices at every discrete step. At first, a sequential Matlab code is generated. Later on, the formulation is modified to use grid computing, thereby a significant reduction in computational time is expected.

Active fault tolerant control of nonlinear systems: The cart-pole example

Marcello Bonfè, Paolo Castaldi, Nicola Mimmo, Silvio Simani (2011)

International Journal of Applied Mathematics and Computer Science

This paper describes the design of fault diagnosis and active fault tolerant control schemes that can be developed for nonlinear systems. The methodology is based on a fault detection and diagnosis procedure relying on adaptive filters designed via the nonlinear geometric approach, which allows obtaining the disturbance de-coupling property. The controller reconfiguration exploits directly the on-line estimate of the fault signal. The classical model of an inverted pendulum on a cart is considered...

Adaptive control of uncertain nonholonomic systems in finite time

Jiankui Wang, Guoshan Zhang, Hongyi Li (2009)

Kybernetika

In this paper, the finite-time stabilization problem of chained form systems with parametric uncertainties is investigated. A novel switching control strategy is proposed for adaptive finite-time control design with the help of Lyapunov-based method and time-rescaling technique. With the proposed control law, the uncertain closed-loop system under consideration is finite-time stable within a given settling time. An illustrative example is also given to show the effectiveness of the proposed controller....

Adaptive stabilization of coupled PDE–ODE systems with multiple uncertainties

Jian Li, Yungang Liu (2014)

ESAIM: Control, Optimisation and Calculus of Variations

The adaptive stabilization is investigated for a class of coupled PDE-ODE systems with multiple uncertainties. The presence of the multiple uncertainties and the interaction between the sub-systems makes the systems to be considered more general and representative, and moreover it may result in the ineffectiveness of the conventional methods on this topic. Motivated by the existing literature, an infinite-dimensional backsteppping transformation with new kernel functions is first introduced to change...

An analytical method for well-formed workflow/Petri net verification of classical soundness

Julio Clempner (2014)

International Journal of Applied Mathematics and Computer Science

In this paper we consider workflow nets as dynamical systems governed by ordinary difference equations described by a particular class of Petri nets. Workflow nets are a formal model of business processes. Well-formed business processes correspond to sound workflow nets. Even if it seems necessary to require the soundness of workflow nets, there exist business processes with conditional behavior that will not necessarily satisfy the soundness property. In this sense, we propose an analytical method...

An extension of the Cayley-Hamilton theorem for nonlinear time-varying systems

Tadeusz Kaczorek (2006)

International Journal of Applied Mathematics and Computer Science

The classical Cayley-Hamilton theorem is extended to nonlinear time-varying systems with square and rectangular system matrices. It is shown that in both cases system matrices satisfy many equations with coefficients being the coefficients of characteristic polynomials of suitable square matrices. The proposed theorems are illustrated with numerical examples.

An Optimal Control Problem for a Predator-Prey Reaction-Diffusion System

N. C. Apreutesei (2010)

Mathematical Modelling of Natural Phenomena

An optimal control problem is studied for a predator-prey system of PDE, with a logistic growth rate of the prey and a general functional response of the predator. The control function has two components. The purpose is to maximize a mean density of the two species in their habitat. The existence of the optimal solution is analyzed and some necessary optimality conditions are established. The form of the optimal control is found in some particular...

An unconditionally stable nonstandard finite difference method applied to a mathematical model of HIV infection

Hasim A. Obaid, Rachid Ouifki, Kailash C. Patidar (2013)

International Journal of Applied Mathematics and Computer Science

We formulate and analyze an unconditionally stable nonstandard finite difference method for a mathematical model of HIV transmission dynamics. The dynamics of this model are studied using the qualitative theory of dynamical systems. These qualitative features of the continuous model are preserved by the numerical method that we propose in this paper. This method also preserves the positivity of the solution, which is one of the essential requirements when modeling epidemic diseases. Robust numerical...

Approximate controllability of infinite dimensional systems of the n-th order

Jerzy Stefan Respondek (2008)

International Journal of Applied Mathematics and Computer Science

The objective of the article is to obtain general conditions for several types of controllability at once for an abstract differential equation of arbitrary order, instead of conditions for a fixed order equation. This innovative approach was possible owing to analyzing the n-th order linear system in the Frobenius form which generates a Jordan transition matrix of the Vandermonde form. We extensively used the fact that the knowledge of the inverse of a Jordan transition matrix enables us to directly...

Approximation of fractional positive stable continuous-time linear systems by fractional positive stable discrete-time systems

Tadeusz Kaczorek (2013)

International Journal of Applied Mathematics and Computer Science

Fractional positive asymptotically stable continuous-time linear systems are approximated by fractional positive asymptotically stable discrete-time systems using a linear Padé-type approximation. It is shown that the approximation preserves the positivity and asymptotic stability of the systems. An optional system approximation is also discussed.

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