Publications

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Palma, L, Coito F, Neves-Silva R.  2003.  Failure Analysis on a Process Plant Model Based on Adaptive Filter Techniques. Abstract

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Palma, LB, Coito FV, Silva RN.  2003.  Fault diagnosis based on black-box models with application to a liquid-level system. Emerging Technologies and Factory Automation, 2003. Proceedings. ETFA’03. IEEE Conference. 2:739–746.: IEEE Abstract

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Palma, L, Coito F, Neves-Silva R, Gil P.  2008.  A Fault Tolerant Approach for Networked Control Systems Using Predictive Models. Abstract

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Palma, L, Neves-Silva R, Coito F.  2003.  Fault tolerant control approach applied to the three-tank system. Abstract

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Matos, C, Batista AG, Ortigueira MD.  2009.  FILTERS: Fractional vs Integer order. Symposium on Fractional Signals and Systems, Lisbon?09. Abstract
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Ortigueira, M.D., Machado, J.A.T. (Eds.).  2006.  Fractional calculus applications in signals and systems. Signal Processing. 86:2503–2504., Number 10: Elsevier Abstract
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Ortigueira, MD.  2011.  Fractional Calculus for Scientists and Engineers. Fractional Calculus for Scientists and Engineers. 84: Springer-Verlag AbstractWebsite
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Ortigueira, MD.  2008.  Fractional Central Differences and Derivatives. Journal of Vibration and Control. 14:1255–1266., Number 9-10 AbstractWebsite

Fractional central differences and derivatives are studied in this article. These are generalisations to real orders of the ordinary positive (even and odd) integer order differences and derivatives, and also coincide with the well known Riesz potentials. The coherence of these definitions is studied by applying the definitions to functions with Fourier transformable functions. Some properties of these derivatives are presented and particular cases studied.

Ortigueira, M.  2006.  Fractional Centred Differences and Derivatives. Proceedings of the 2nd IFAC Workshop on Fractional Differentiation and its Applications. Abstract
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Coito, F, Ortigueira M.  2008.  Fractional Controller Design Trough Multi-Objective Optimization. 8th Portuguese Conference on Automatic Control ? CONTROLO?2008. Abstract
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Coito, F, Ortigueira M.  2008.  Fractional Controller Design Trough Multi-Objective Optimization. Abstract

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Ortigueira, MD.  2009.  Fractional Derivatives and Linear Systems. Mobile Computing Research and Applications. :219–269.: Nova Science Publishers, Inc. Abstract
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Ortigueira, M.  2005.  Fractional Differences Integral Representation and its use to define Fractional Differintegrations, August. the ENOC-2005, Fifth EUROMECH Nonlinear Dynamics Conference. Abstract
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Ortigueira, M, Matos C, Piedade MS.  2002.  Fractional Discrete-Time Signal Processing: Scale Conversion and Linear Prediction. Nonlinear Dynamics. :173–190. AbstractWebsite
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Matos, C, Ortigueira MD.  2010.  Fractional Filters: An Optimization Approach. Emerging Trends in Technological Innovation. 314:361–366. Abstract

The design and optimization of fractional filters is considered in this paper. Some of the classic filter architectures are presented and their performances relatively to an ideal amplitude spectrum evaluated. The fractional filters are designed using the differential evolution optimization algorithm for computing their parameters. To evaluate the performances of all the filters the quadratic error between the computed amplitude is calculated against an ideal (goal) response. The fractional filters have a better behavior, both in the pass and reject-band.

Ortigueira, MD, Batista AG.  2004.  A Fractional Linear System View of the Fractional Brownian Motion, December. Nonlinear Dynamics. 38:295–303., Number 1-4: Springer AbstractWebsite

A definition of the fractional Brownian motion based on the fractional differintegrator characteristics is proposed and studied. It is shown that the model enjoys the usually required properties. A discrete-time version based in the backward difference and in the bilinear transformation is considered. Some results are presented.

Batista, AG, Ortigueira MD.  2004.  A Fractional Linear System View of the Fractional Brownian Motion. Nonlinear Dynamics. :295-303. Abstract
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Ortigueira, M.  2008.  A fractional quantum derivative. 3rd IFAC Workshop on Fractional Differentiation and its Applications. Abstract
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Ortigueira, MD.  2010.  The fractional quantum derivative and its integral representations? Communications in Nonlinear Science and Numerical Simulation. 15:956–962., Number 4: Elsevier B.V. AbstractWebsite

The quantum fractional derivative is defined using formulations analogue to the common Grünwald?Letnikov derivatives. While these use a linear variable scale, the quantum derivative uses an exponential scale and is defined in R? or R?. Two integral formulations similar to the usual Liouville derivatives are deduced with the help of the Mellin transform.

Ortigueira, MD.  2011.  The Fractional Quantum Derivative and the Fractional Linear Scale Invariant Systems. Fractional Calculus for Scientists and Engineers. 84:123–144.: Springer-Verlag Abstract

The normal way of introducing the notion of derivative is by means of the limit of an incremental ratio that can assume three forms, depending the used translations as we saw in Chaps. 1 and 4. On the other hand, in those derivatives the limit operation is done over a set of points uniformly spaced: a linear scale was used. Here we present an alternative derivative, that is valid only for t {\ensuremath{>}} 0 or t {\ensuremath{<}} 0 and uses an exponential scale

Ortigueira, M.  2008.  The Fractional Quantum Derivative and the Generalised Euler-Cauchy Equation. 2nd Conference on Nonlinear Science and Complexity, NSC08. Abstract
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Ortigueira, M, Coito F.  2004.  From Differences to Derivatives. Fractional Calculus & Applied Analysis. 7:459–471., Number 4: Institute of Mathematics & Informatics AbstractWebsite
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Ortigueira, MD, Coito F.  2004.  From Differences to Derivatives. Fractional Calculus and Applied Analysis. 7:459., Number 4: INSTITUTE OF MATHEMATICS AND INFORMATICS BULGARIAN ACADEMY OF SCIENCES Abstract

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Duarte Ortigueira, M, Coito F.  2004.  From Differences to Derivatives. : Institute of Mathematics and Informatics Bulgarian Academy of Sciences Abstract

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Leal, A, Monteiro J, Secca MF, Jordão C.  2009.  Functional brain mapping of ictal activity in gelastic epilepsy associated with hypothalamic hamartoma: A case report. Epilepsia. 50(6):1624-1631.