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Comparison of active control techniques over a dihedral plane

Emmanuel Creusé (2010)

ESAIM: Control, Optimisation and Calculus of Variations

This work is devoted to the numerical comparison of four active control techniques in order to increase the pressure recovery generated by the deceleration of a slightly compressible viscous flow over a dihedral plane. It is performed by the use of vortex generator jets and intrusive sensors. The governing equations, the two-dimensional direct numerical simulation code and the flow configuration are first briefly recalled. Then, the objective of the control is carefully displayed, and the uncontrolled...

Comparison of linear control methods for an AMB system

Wojciech Grega, Adam Pilat (2005)

International Journal of Applied Mathematics and Computer Science

The contactless nature of active magnetic bearings brings about many advantages over the conventional bearing while industrial real-time applications are often limited by the significant complexity of control algorithms. This paper presents the application of an LQ controller to an active magnetic bearing system (AMB). Two control strategies are presented and compared: local and global. In the first case the rotor is modelled as two separated masses located at the bearing. In the second case rotor...

Comparison of six models of antiangiogenic therapy

Andrzej Świerniak (2009)

Applicationes Mathematicae

Six models of antiangiogenic therapy are compared and analyzed from control-theoretic point of view. All of them consist of a model of tumor growth bounded by the capacity of a vascular network developed by the tumor in the process of angiogenesis and different models of dynamics of this network, and are based on the idea proposed by Hahnfeldt et al. Moreover, we analyse optimal control problems resulting from their use in treatment protocol design.

Comparison of the stability boundary and the frequency response stability condition in learning and repetitive control

Szathys Songschon, Richard Longman (2003)

International Journal of Applied Mathematics and Computer Science

In iterative learning control (ILC) and in repetitive control (RC) one is interested in convergence to zero tracking error as the repetitions of the command or the periods in the command progress. A condition based on steady state frequency response modeling is often used, but it does not represent the true stability boundary for convergence. In this paper we show how this useful condition differs from the true stability boundary in ILC and RC, and show that in applications of RC the distinction...

Comparison principle approach to utility maximization

Peter Imkeller, Victor Nzengang (2015)

Banach Center Publications

We consider the problem of optimal investment for maximal expected utility in an incomplete market with trading strategies subject to closed constraints. Under the assumption that the underlying utility function has constant sign, we employ the comparison principle for BSDEs to construct a family of supermartingales leading to a necessary and sufficient condition for optimality. As a consequence, the value function is characterized as the initial value of a BSDE with Lipschitz growth.

Compartmental Models of Migratory Dynamics

J. Knisley, T. Schmickl, I. Karsai (2011)

Mathematical Modelling of Natural Phenomena

Compartmentalization is a general principle in biological systems which is observable on all size scales, ranging from organelles inside of cells, cells in histology, and up to the level of groups, herds, swarms, meta-populations, and populations. Compartmental models are often used to model such phenomena, but such models can be both highly nonlinear and difficult to work with.Fortunately, there are many significant biological systems that are amenable to linear compartmental models which are often...

Complementary matrices in the inclusion principle for dynamic controllers

Lubomír Bakule, José Rodellar, Josep M. Rossell (2003)

Kybernetika

A generalized structure of complementary matrices involved in the input-state- output Inclusion Principle for linear time-invariant systems (LTI) including contractibility conditions for static state feedback controllers is well known. In this paper, it is shown how to further extend this structure in a systematic way when considering contractibility of dynamic controllers. Necessary and sufficient conditions for contractibility are proved in terms of both unstructured and block structured complementary...

Completitud esencial de la clase de controles basados en un proceso suficiente.

Pilar Ibarrola Muñoz, Javier Yáñez Gestoso (1985)

Trabajos de Estadística e Investigación Operativa

Se define en este artículo el concepto de proceso suficiente para un proceso de control, así como el de control basado en un proceso suficiente. Se demuestra a continuación que el conjunto de controles basados en un proceso suficiente forma una clase esencialmente completa; por consiguiente, dado un control, existe un control basado en el proceso suficiente que tiene el mismo coste esperado que el anterior.

Complex calculus of variations

Michel Gondran, Rita Hoblos Saade (2003)

Kybernetika

In this article, we present a detailed study of the complex calculus of variations introduced in [M. Gondran: Calcul des variations complexe et solutions explicites d’équations d’Hamilton–Jacobi complexes. C.R. Acad. Sci., Paris 2001, t. 332, série I]. This calculus is analogous to the conventional calculus of variations, but is applied here to 𝐂 n functions in 𝐂 . It is based on new concepts involving the minimum and convexity of a complex function. Such an approach allows us to propose explicit solutions...

Composite control of the n -link chained mechanical systems

Jiří Zikmund (2008)

Kybernetika

In this paper, a new control concept for a class of underactuated mechanical system is introduced. Namely, the class of n -link chains, composed of rigid links, non actuated at the pivot point is considered. Underactuated mechanical systems are those having less actuators than degrees of freedom and thereby requiring more sophisticated nonlinear control methods. This class of systems includes among others frequently used for the modeling of walking planar structures. This paper presents the stabilization...

Computation of linear algebraic equations with solvability verification over multi-agent networks

Xianlin Zeng, Kai Cao (2017)

Kybernetika

In this paper, we consider the problem of solving a linear algebraic equation A x = b in a distributed way by a multi-agent system with a solvability verification requirement. In the problem formulation, each agent knows a few columns of A , different from the previous results with assuming that each agent knows a few rows of A and b . Then, a distributed continuous-time algorithm is proposed for solving the linear algebraic equation from a distributed constrained optimization viewpoint. The algorithm is...

Computation of realizations composed of dynamic and static parts of improper transfer matrices

Tadeusz Kaczorek (2007)

International Journal of Applied Mathematics and Computer Science

The problem of computing minimal realizations of a singular system decomposed into a standard dynamical system and a static system of a given improper transfer matrix is formulated and solved. A new notion of the minimal dynamical-static realization is introduced. It is shown that there always exists a minimal dynamical-static realization of a given improper transfer matrix. A procedure for the computation of a minimal dynamical-static realization for a given improper transfer matrix is proposed...

Computer aided design of mechatronic systems

Zbigniew Mrozek (2003)

International Journal of Applied Mathematics and Computer Science

Any successful company must react quickly to changing trends in the market. New products should be designed and manufactured quicker and cheaper than counter partners do. A shorter design time provides a distinct competitive advantage. The paper describes two approaches towards designing interdisciplinary mechatronic systems: the first is visual modelling with the UML, the second is physical modelling with Modelica.

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