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Research paper thumbnail of Neural Observer-Based Approach to Fault Detection and Isolation of a Three-Tank System

The simulated laboratory set-up Three-Tank System is investigated from the standpoint of fault-to... more The simulated laboratory set-up Three-Tank System is investigated from the standpoint of fault-tolerant control. The problem of robust model-based diagnosis is therefore addressed. Dynamic neural networks with mixed structure are used to design different observer-based schemes. Symptom evaluation is based on static neural nets. They are used to classify the obtained residuals. Different classifiers and decision criteria are analysed. Experimental results of simulation are included into a comparative study. This refers to actuator, component and instrument fault detection and isolation.

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Research paper thumbnail of An approach to robust fault detection. I: A method for designing fault detection observers

This paper presents a method for the design of unknown input fault detection observers. In case t... more This paper presents a method for the design of unknown input fault detection observers. In case the mathematical requirements are satisfied, this method provides a perfect decoupling between unknown inputs and faults. If this is not possible because certain prerequisites are not fulfilled, an optimal compromise is described. This design is based on the Observer Canonical Form of the system. Finally, a Matlab package based on the presented theoretical approach is described.

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Research paper thumbnail of ON THE n-ORDER ACCELERATIONS DISTRIBUTION DURING RIGID MOTION

The properties of the n-order accelerations distribution of a rigid body under general motion are... more The properties of the n-order accelerations distribution of a rigid body under general motion are systematically studied based on tensor algebra. A tensor represents an R -linear mapping of the R -linear space of free vectors V into V . It may be represented by a matrix only after a basis in V was selected. Preferring an orthonormal basis simplifies the calculus, but this particular choice may conceal some essential properties. This paper uses the notion of rigid basis associated to a spherical rigid motion in order to point out some properties of the n-order accelerations tensor.

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Research paper thumbnail of EXPLICIT SOLUTIONS TO SOME VECTORIAL DIFFERENTIAL EQUATIONS I. General Results

The aim of this paper is to present a procedure that allows to point out the vectorial solutions ... more The aim of this paper is to present a procedure that allows to point out the vectorial solutions to some Cauchy problems not depicted in any dynamics treatise yet. The main results are presented in Theorems 3 and 4 and show the explicit form of these solutions.

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Research paper thumbnail of Boundedness properties of timed continuous Petri nets with interval firing rates

This paper presents the concepts of d-upper boundedness and weakly δ-conservativeness for general... more This paper presents the concepts of d-upper boundedness and weakly δ-conservativeness for general Timed Continuous Petri nets. The analysis is extended to the case when the exact values of the firing rates of the transitions are uncertain, but the intervals of their values are known (the firing rates are constant, between prescribed minimal and maximal values). The example of a manufacturing system is included in order to illustrate these concepts.

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Research paper thumbnail of P0-property and linear inequalities in positive systems analysis

A matrix M ∊ Rn×n is a P0-matrix if every principal minor of M is nonnegative. We use this concep... more A matrix M ∊ Rn×n is a P0-matrix if every principal minor of M is nonnegative. We use this concept in a generalized form, called row (column)-P0-property, which refers to a finite set of matrices M = {M1,…, MN} ⊂ Rn×n. In the current work, the set M collects matrices of the form Mθ = Aθ − rI, θ = 1,…, N, with Aθ ∊ Rn×n essentially nonnegative and Hurwitz stable, and r < 0. Relying on the P0-property of M, we investigate the existence of nonnegative vectors v ∊Rn (depending on r

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Research paper thumbnail of Invariance for stochastic differential systems with time-dependent constraining sets

Acta Mathematica Sinica, English Series, 2015

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Research paper thumbnail of Symbolic Representation of Continual and Discrete Signals on Finite Order Algebras

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Research paper thumbnail of New Results in the State-Space Analysis of Positive Linear Systems

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Research paper thumbnail of Lyapunov functions and Lyapunov inequalities defined by Hölder p-norms for linear time-variant systems

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Research paper thumbnail of New Results on the Stability of Continuous-Time Cellular Neural Networks

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Research paper thumbnail of Novel results in the qualitative analysis of continuous-time bidirectional associative memories

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Research paper thumbnail of Diagonal Invariance and Comparison Methods

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Research paper thumbnail of P 0-property and linear inequalities in positive systems analysis

ABSTRACT A matrix M ∊ Rn×n is a P0-matrix if every principal minor of M is nonnegative. We use th... more ABSTRACT A matrix M ∊ Rn×n is a P0-matrix if every principal minor of M is nonnegative. We use this concept in a generalized form, called row (column)-P0-property, which refers to a finite set of matrices M = {M1,…, MN} ⊂ Rn×n. In the current work, the set M collects matrices of the form Mθ = Aθ − rI, θ = 1,…, N, with Aθ ∊ Rn×n essentially nonnegative and Hurwitz stable, and r &lt; 0. Relying on the P0-property of M, we investigate the existence of nonnegative vectors v ∊Rn (depending on r

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Research paper thumbnail of Instruments for topology-based analysis in Petri Net Toolbox

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Research paper thumbnail of MANUFACTURING SYSTEMS ANALYSIS AND DESIGN

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Research paper thumbnail of Advanced Control, Modeling and Simulation

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Research paper thumbnail of Componentwise Stability of BAM Neural Networks with Uncertainties

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Research paper thumbnail of COMPONENTWISE STABILITY OF DISCRETE-TIME INTERVAL BIDIRECTIONAL ASSOCIATIVE MEMORIES

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Research paper thumbnail of INTERVAL MATRIX SYSTEMS–INVARIANT SETS AND STABILITY PROPERTIES

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Research paper thumbnail of Neural Observer-Based Approach to Fault Detection and Isolation of a Three-Tank System

The simulated laboratory set-up Three-Tank System is investigated from the standpoint of fault-to... more The simulated laboratory set-up Three-Tank System is investigated from the standpoint of fault-tolerant control. The problem of robust model-based diagnosis is therefore addressed. Dynamic neural networks with mixed structure are used to design different observer-based schemes. Symptom evaluation is based on static neural nets. They are used to classify the obtained residuals. Different classifiers and decision criteria are analysed. Experimental results of simulation are included into a comparative study. This refers to actuator, component and instrument fault detection and isolation.

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Research paper thumbnail of An approach to robust fault detection. I: A method for designing fault detection observers

This paper presents a method for the design of unknown input fault detection observers. In case t... more This paper presents a method for the design of unknown input fault detection observers. In case the mathematical requirements are satisfied, this method provides a perfect decoupling between unknown inputs and faults. If this is not possible because certain prerequisites are not fulfilled, an optimal compromise is described. This design is based on the Observer Canonical Form of the system. Finally, a Matlab package based on the presented theoretical approach is described.

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Research paper thumbnail of ON THE n-ORDER ACCELERATIONS DISTRIBUTION DURING RIGID MOTION

The properties of the n-order accelerations distribution of a rigid body under general motion are... more The properties of the n-order accelerations distribution of a rigid body under general motion are systematically studied based on tensor algebra. A tensor represents an R -linear mapping of the R -linear space of free vectors V into V . It may be represented by a matrix only after a basis in V was selected. Preferring an orthonormal basis simplifies the calculus, but this particular choice may conceal some essential properties. This paper uses the notion of rigid basis associated to a spherical rigid motion in order to point out some properties of the n-order accelerations tensor.

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Research paper thumbnail of EXPLICIT SOLUTIONS TO SOME VECTORIAL DIFFERENTIAL EQUATIONS I. General Results

The aim of this paper is to present a procedure that allows to point out the vectorial solutions ... more The aim of this paper is to present a procedure that allows to point out the vectorial solutions to some Cauchy problems not depicted in any dynamics treatise yet. The main results are presented in Theorems 3 and 4 and show the explicit form of these solutions.

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Research paper thumbnail of Boundedness properties of timed continuous Petri nets with interval firing rates

This paper presents the concepts of d-upper boundedness and weakly δ-conservativeness for general... more This paper presents the concepts of d-upper boundedness and weakly δ-conservativeness for general Timed Continuous Petri nets. The analysis is extended to the case when the exact values of the firing rates of the transitions are uncertain, but the intervals of their values are known (the firing rates are constant, between prescribed minimal and maximal values). The example of a manufacturing system is included in order to illustrate these concepts.

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Research paper thumbnail of P0-property and linear inequalities in positive systems analysis

A matrix M ∊ Rn×n is a P0-matrix if every principal minor of M is nonnegative. We use this concep... more A matrix M ∊ Rn×n is a P0-matrix if every principal minor of M is nonnegative. We use this concept in a generalized form, called row (column)-P0-property, which refers to a finite set of matrices M = {M1,…, MN} ⊂ Rn×n. In the current work, the set M collects matrices of the form Mθ = Aθ − rI, θ = 1,…, N, with Aθ ∊ Rn×n essentially nonnegative and Hurwitz stable, and r < 0. Relying on the P0-property of M, we investigate the existence of nonnegative vectors v ∊Rn (depending on r

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Research paper thumbnail of Invariance for stochastic differential systems with time-dependent constraining sets

Acta Mathematica Sinica, English Series, 2015

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Research paper thumbnail of Symbolic Representation of Continual and Discrete Signals on Finite Order Algebras

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Research paper thumbnail of New Results in the State-Space Analysis of Positive Linear Systems

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Research paper thumbnail of Lyapunov functions and Lyapunov inequalities defined by Hölder p-norms for linear time-variant systems

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Research paper thumbnail of New Results on the Stability of Continuous-Time Cellular Neural Networks

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Research paper thumbnail of Novel results in the qualitative analysis of continuous-time bidirectional associative memories

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Research paper thumbnail of Diagonal Invariance and Comparison Methods

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Research paper thumbnail of P 0-property and linear inequalities in positive systems analysis

ABSTRACT A matrix M ∊ Rn×n is a P0-matrix if every principal minor of M is nonnegative. We use th... more ABSTRACT A matrix M ∊ Rn×n is a P0-matrix if every principal minor of M is nonnegative. We use this concept in a generalized form, called row (column)-P0-property, which refers to a finite set of matrices M = {M1,…, MN} ⊂ Rn×n. In the current work, the set M collects matrices of the form Mθ = Aθ − rI, θ = 1,…, N, with Aθ ∊ Rn×n essentially nonnegative and Hurwitz stable, and r &lt; 0. Relying on the P0-property of M, we investigate the existence of nonnegative vectors v ∊Rn (depending on r

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Research paper thumbnail of Instruments for topology-based analysis in Petri Net Toolbox

Bookmarks Related papers MentionsView impact

Research paper thumbnail of MANUFACTURING SYSTEMS ANALYSIS AND DESIGN

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Advanced Control, Modeling and Simulation

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Componentwise Stability of BAM Neural Networks with Uncertainties

Bookmarks Related papers MentionsView impact

Research paper thumbnail of COMPONENTWISE STABILITY OF DISCRETE-TIME INTERVAL BIDIRECTIONAL ASSOCIATIVE MEMORIES

Bookmarks Related papers MentionsView impact

Research paper thumbnail of INTERVAL MATRIX SYSTEMS–INVARIANT SETS AND STABILITY PROPERTIES

Bookmarks Related papers MentionsView impact