Search results for "continuous systems"

showing 7 items of 7 documents

On singularities of discontinuous vector fields

2003

Abstract The subject of this paper concerns the classification of typical singularities of a class of discontinuous vector fields in 4D. The focus is on certain discontinuous systems having some symmetric properties.

Class (set theory)Mathematics(all)SingularityNormal formGeneral MathematicsMathematical analysisTopologyDiscontinuous systemsReversibilityGravitational singularityVector fieldDiscontinuous vector fieldsFocus (optics)MathematicsBulletin des Sciences Mathématiques
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Hidden attractors in electromechanical systems with and without equilibria

2016

This paper studies hidden oscillations appearing in electromechanical systems with and without equilibria. Three different systems with such effects are considered: translational oscillator-rotational actuator, drilling system actuated by a DC-motor and drilling system actuated by induction motor. We demonstrate that three systems experience hidden oscillations in sense of mathematical definition. While some of these hidden oscillations can be easily seen in natural physical experiments, the localization of others requires special efforts. peerReviewed

hidden attractorsdrilling systemdiscontinuous systemsSommerfeld effect
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Robust control of uncertain multi-inventory systems via linear matrix inequality

2008

We consider a continuous time linear multi inventory system with unknown demands bounded within ellipsoids and controls bounded within ellipsoids or polytopes. We address the problem of "-stabilizing the inventory since this implies some reduction of the inventory costs. The main results are certain conditions under which "-stabilizability is possible through a saturated linear state feedback control. All the results are based on a Linear Matrix Inequalities (LMIs) approach and on some recent techniques for the modeling and analysis of polytopic systems with saturations.

Mathematical optimizationLinear Matrix InequalitiesPolytopeDynamical Systems (math.DS)stock control93xxcontinuous systems linear matrix inequalities linear systems manufacturing systems robust control state feedback stock control uncertain systemsimpulse control inventory control hybrid systemsSettore ING-INF/04 - AutomaticaControl theoryFOS: Mathematicsmanufacturing systemsMathematics - Dynamical Systemslinear matrix inequalitiesstate feedbackTime complexityMathematics - Optimization and ControlInventory systemsMathematicsInventory controlLinear Matrix Inequalities; Inventory systemsLinear systemlinear systemsLinear matrix inequality93Cxx;93xxLinearity93Cxxhybrid systemsEllipsoidComputer Science Applicationsimpulse control; inventory control; hybrid systemsuncertain systemsControl and Systems EngineeringOptimization and Control (math.OC)Control systemBounded functioncontinuous systemsPerpetual inventorycontinuous systems; linear matrix inequalities; linear systems; manufacturing systems; robust control; state feedback; stock control; uncertain systemsinventory controlRobust controlSettore MAT/09 - Ricerca Operativarobust controlimpulse control
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Invariant varieties of discontinuous vector fields

2004

We study the geometric qualitative behaviour of a class of discontinuous vector fields in four dimensions around typical singularities. We are mainly interested in giving the conditions under which there exist one-parameter families of periodic orbits (a result that can be seen as one analogous to the Lyapunov centre theorem). The focus is on certain discontinuous systems having some symmetric properties. We also present an algorithm which detects and computes periodic orbits.

Lyapunov functionApplied MathematicsMathematical analysisGeneral Physics and AstronomyStatistical and Nonlinear PhysicsDiscontinuous systemssymbols.namesakeSingularitysymbolsPeriodic orbitsGravitational singularityVector fieldInvariant (mathematics)Mathematical PhysicsMathematicsNonlinearity
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PIECEWISE SMOOTH REVERSIBLE DYNAMICAL SYSTEMS AT A TWO-FOLD SINGULARITY

2012

This paper focuses on the existence of closed orbits around a two-fold singularity of 3D discontinuous systems of the Filippov type in the presence of symmetries.

Essential singularitySingularityDynamical systems theoryStructural stabilityApplied MathematicsModeling and SimulationHomogeneous spaceMathematical analysisPiecewiseSingularity functionDiscontinuous systemsEngineering (miscellaneous)MathematicsInternational Journal of Bifurcation and Chaos
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On some bifurcation analysis techniques for continuous systems

2016

This paper is devoted to techniques in bifurcation analysis for continuous mechanical systems, concentrating on polynomial equations and implicitly given functions. These are often encountered in problems of mechanics and especially in stability analysis. Taking a classical approach, we summarize the relevant features of the cubic polynomial equation, and present some new aspects for asymptotics and parametric representation of the solutions. This is followed by a brief look into the implicit function theorem as a tool for analyzing bifurcations. As an example from mechanics, we consider bifurcations in the transverse free vibration problem of an axially compressed beam. peerReviewed

continuous systemsimplicit functions [asymptotic analysis]bifurcation analysisbeam
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Theory of Differential Inclusions and Its Application in Mechanics

2017

The following chapter deals with systems of differential equations with discontinuous right-hand sides. The key question is how to define the solutions of such systems. The most adequate approach is to treat discontinuous systems as systems with multivalued right-hand sides (differential inclusions). In this work, three well-known definitions of solution of discontinuous system are considered. We will demonstrate the difference between these definitions and their application to different mechanical problems. Mathematical models of drilling systems with discontinuous friction torque characteristics are considered. Here, opposite to classical Coulomb symmetric friction law, the friction torqu…

Lyapunov function0209 industrial biotechnologyWork (thermodynamics)Mathematical modelDifferential equationMathematical analysis02 engineering and technologyDiscontinuous systems01 natural sciencessymbols.namesake020901 industrial engineering & automationDifferential inclusion0103 physical sciencesCoulombsymbols010301 acousticsFriction torqueMathematics
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